NORME INTERNATIONALE CEI IEC INTERNATIONAL STANDARD 61982 3 Première édition First edition 2001 06 Accumulateurs pour la propulsion des véhicules routiers électriques � Partie 3 Essais de performance[.]
Profil du micro-cycle de référence
Le profil du micro-cycle de référence est basé sur l’essai de stress dynamique (Dynamic Stress
Test ou DST), établi par le United States Advanced Battery Consortium (USABC), celui-ci étant lui-même basé sur le cycle d’essais Simplified Federal Urban Driving Cycle (SFUDS).
The analysis of the duration of stages and power levels for each stage of this micro-cycle indicates that, for an average discharge power of 3 kW, the maximum power at stage 15 should be set at 24 kW A comprehensive list of the 20 stages of the micro-cycle, each with a maximum power of 24 kW, is provided in Table 1 The discharge powers are recorded as negative values, and the tolerances for this cycle are detailed in section 5.2.2.
Tableau 1 – Liste des valeurs DST pour un micro-cycle, dont la puissance maximale est 24 kW
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
To ensure the test accurately reflects vehicle operation, the discharge rate and battery size must align with those used in actual town driving Currently, the primary constraint in battery selection is the weight that the vehicle can support As advanced batteries emerge, the focus will shift to the range or driving time suitable for urban environments Consequently, battery selection is based on two key criteria: weight and, if the weight capacity exceeds the required range, the range itself The selected figures should be representative of typical town operation.
Energy consumption, from the battery : 100 Wh/tonne × km.
In addition, the basic tests shall be performed at an ambient temperature of 25 °C.
The average power consumption of a vehicle is 3 kW per tonne, translating to an energy usage of 15 kWh for a one-tonne vehicle This battery capacity allows the vehicle to travel up to 150 km in urban conditions.
The specific weight, volume, and capacity of batteries selected for a vehicle are influenced by various factors related to the vehicle itself and the available space for the battery system.
As a guide to battery selection only, the following figures are proposed for consideration:
Maximum battery weight fraction in the fully laden vehicle: 30 %.
Maximum range required for an urban vehicle: 150 km.
4.1 Basic current discharge micro-cycle
The basic current discharge micro-cycle is based on the Dynamic Stress Test (DST) established by the United States Advanced Battery Consortium (USABC), in turn based on the earlier
The Simplified Federal Urban Driving Cycle (SFUDS) test cycle analysis reveals that the step durations and percentage powers for each step must be adjusted For an average discharge power of 3 kW, the micro-cycle will be scaled to ensure that the peak power in step 15 is optimized.
The 20-step DST micro-cycle, featuring a peak power of 24 kW, is detailed in Table 1 below, with discharge powers represented as negative values Tolerances for this cycle are specified in section 5.2.2.
Table 1 – List of DST values for one micro-cycle, where the peak power is 24 kW
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
The values mentioned for regenerative powers are those necessary to meet the DST power profile To prevent dangerous overloads, the actual power delivered to the battery may, in some cases, be restricted by the battery management system.
L'essai de décharge de référence consiste en la succession répétée des micro-cycles de référence jusqu’à ce que la batterie soit déchargée ou l’essai terminé pour une autre raison.
Ajustement en fonction de la performance de véhicule, si nécessaire
The energy consumption of a high-performance vehicle may exceed that of a lower-performance vehicle; however, due to traffic constraints, the difference in energy consumption is minimal during normal city use Battery and vehicle manufacturers can modify discharge tests to account for the increased battery demand of high-performance vehicles To tailor the procedure for a specific vehicle type, the values for levels 15 (maximum discharge power) and 19 (maximum regeneration power) in the reference micro-cycle should be adjusted in magnitude but not in duration to accurately simulate the actual power delivered by the vehicle's traction system A battery designed for a high-performance vehicle will have increased power values, while the same battery for a more basic vehicle will have reduced values, with other power levels and times remaining unchanged An example of an adapted micro-cycle for testing a high-performance vehicle battery, assuming a test mass of 1 ton, is provided in Table 2, which includes the maximum discharge power of the traction system.
100 kW et la puissance maximale de régénération est de 50 kW.
Tableau 2 – Liste des valeurs DST pour un micro-cycle pour un véhicule à performances élevées
Essai de sélection de la batterie
Choosing the right battery for testing is an iterative process that relies on the relationship between the battery supplier and the vehicle manufacturer, which becomes more critical during testing Initially, the vehicle manufacturer must define the power levels for the traction chain during discharge and regenerative braking Subsequently, the battery manufacturer should provide a representative battery sample for evaluation, utilizing a reference micro-cycle profile that may be adjusted to accurately reflect the actual capabilities of the traction chain in both discharge and regenerative braking scenarios.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
The regenerative power values mentioned are necessary to meet the DST power profile To avoid significant overcharging, the battery management system may restrict the actual power supplied to the battery in certain situations.
The reference test cycle consists of repeated micro-cycles until the battery is discharged or the test is terminated for some other reason.
4.2 Adjustment for vehicle performance, if required
High-performance vehicles often consume more energy than low-performance ones; however, in typical urban driving conditions, the difference in energy consumption is minimal due to traffic constraints To address the unique demands placed on batteries by high-performance vehicles, the battery testing procedure can be tailored to each vehicle, contingent upon an agreement between the battery and vehicle manufacturers This customization includes specific steps to assess maximum discharge power.
The maximum regenerative power of the basic micro-cycle profile must be adjusted in magnitude to match the actual power capability of the vehicle's drive system, while its duration remains unchanged For high-performance vehicles, the peak values of the battery system will be increased, whereas for low-performance vehicles, these values will be reduced The other steps' magnitude and duration will stay the same For instance, a micro-cycle designed to test a battery in a high-performance vehicle with a test weight of one tonne demonstrates a maximum drive system power capability of 100 kW and a maximum regenerative power of 50 kW, as illustrated in Table 2.
Table 2 – List of DST values for one micro-cycle, adapted for a high performance vehicle
Selecting the right battery for testing is an iterative process that relies on the collaboration between the battery supplier and the car manufacturer, with understanding improving as tests progress Initially, the vehicle manufacturer must assess the power requirements for the drive system, including both driving and regenerative braking Subsequently, the battery manufacturer should provide a representative battery sample for evaluation, utilizing a basic current discharge profile that may be adjusted to accurately represent the drive system's power capabilities during both driving and regenerative braking.
The battery manufacturer must provide a battery management system that connects to the test bench or specify the limits of the battery under test A complete capacity test must be conducted on a representative sample to enable a calculated assessment of the vehicle's range post-test Tests should be repeated while maintaining the same power profile and using batteries of the same design but with different masses Additionally, a graph illustrating the vehicle's calculated range as a function of battery mass must be created.
This will enable the vehicle manufacturer and the battery manufacturer to assess the battery's suitability for the application by identifying its limiting factor before initiating a comprehensive testing program.
Sélection de la batterie et préparation pour les essais
A battery, including a management system and auxiliary components, must be prepared for testing according to the manufacturer's instructions It is essential to document the battery preparation procedures Compatibility among the various systems involved, such as the battery management system, vehicle powertrain, and laboratory test bench, should be thoroughly verified by all parties before testing begins During the test, the battery must be placed in an environment where air circulation and ambient temperature reflect the conditions experienced in a vehicle used in urban settings.
For battery selection, it is advised that the maximum weight should not exceed 30% of the vehicle's total weight when fully loaded, or that its capacity should not allow for a range greater than 150 km.
Battery preparation is crucial for the optimal performance of vehicles, but it can pose significant drawbacks for certain battery types For instance, batteries operating at high temperatures may require a heating period of 24 hours or more, while others, akin to fuel cells, necessitate heating before each use.
NOTE 3 La préparation des batteries pour des essais n’est pas une nouveauté; plusieurs cycles peuvent être effectués sur les éléments et batteries afin d’obtenir l’assurance d’une capacité convenable.
It is possible to conduct selection tests on battery modules, provided that the battery management system's operation and thermal conditions are simulated These modules must have the same capacity as the complete battery and a nominal voltage of at least 12 V.
Essais sur la batterie
Procédure d’essai
The battery must be fully charged according to the manufacturer's instructions at an ambient temperature of 25 °C Testing should be conducted at this temperature unless otherwise specified, and under the same air circulation conditions as if the battery were installed in the vehicle Air circulation must be maintained during discharge but not during charging Heating or cooling of the battery powered by the battery system should be activated if required by the battery management system When an external power source is used to supply energy to the battery management system, the energy consumed must be recorded and reported.
It is acceptable to use an average airflow over the battery instead of adjusting the airflow based on the vehicle's calculated speed For testing purposes, it is recommended to maintain a constant airflow rate that corresponds to an average speed of 30 km/h.
The battery manufacturer is required to provide a battery management system (BMS) for interfacing with the test bench, or to specify any limitations of the tested battery Comprehensive capacity tests must be performed on a representative sample to enable the calculation of the vehicle's range These tests should be repeated with batteries of the same design but varying weights, and a graph must be created to illustrate the relationship between the calculated vehicle range and battery weight.
This process enables both the vehicle and battery manufacturers to evaluate the battery's compatibility with the application by identifying its power limiting size prior to initiating an extensive testing program.
5.1 Battery selection and preparation for test
To ensure accurate testing, a battery, along with its management system and auxiliaries, must be prepared according to the battery manufacturer's instructions and the vehicle manufacturer's requirements Prior to testing, all parties involved must verify the compatibility of the control elements across the battery management system, vehicle drive system, and laboratory test bench Additionally, the battery should be positioned during the test to replicate the airflow and ambient temperature conditions typical of a vehicle operating in urban environments.
NOTE 1 As a guide to selection only, the maximum weight should be limited to 30 % of the total laden vehicle weight or the battery capacity should be chosen such that the anticipated range is limited to 150 km.
NOTE 2 If battery preparation is a significant and frequent factor in the operation of the vehicle system, this may be a major disadvantage of that particular battery As a specific example, batteries which operate at an elevated temperature may require a one-off heat-up period of 24 h or more and others, with similarities to fuel cells, may require a “warm up” period before each use.
NOTE 3 Preparation of batteries for test is not new; cells and batteries may be conditioned for a number of cycles to ensure that an acceptable capacity is being delivered.
Screening tests on battery sub-units are permissible if the battery management system and thermal conditions are accurately simulated The sub-unit being tested must match the full battery's capacity and have a nominal voltage of at least 12 V.
The battery system must be fully charged at an ambient temperature of 25 °C, following the manufacturer's guidelines Testing should occur at this temperature and under typical airflow conditions similar to those in a vehicle Airflow must be maintained during discharge but not during charging If necessary, battery heating or cooling powered by the battery system should be operational Additionally, any energy consumed from an external power source for the battery management system must be recorded and reported.
It is permissible to utilize an average airflow over the battery instead of adjusting the flow based on the calculated vehicle speed For testing purposes, it is advisable to maintain a constant airflow rate that aligns with an average vehicle speed of 30 km/h.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Précision des mesures
La précision générale de valeurs contrôlées (ou mesurées), relatives aux valeurs spécifiées
(ou réelles), doit être entre les tolérances suivantes:
Puissance: ±2 % de la valeur exigée
Temps: ±1 % de la valeur exigée
Taux de variation de puissance: ≤1 s d’une valeur de puissance établie à l’autre.
The transition between power levels during the micro-cycle should be executed in such a way that the midpoint of the effective transition aligns with the specified point for the transition.
La durée totale pour chaque micro-cycle complet doit être de 360 s ± 1 s.
Détermination de l’énergie embarquée de la batterie
The battery's embedded energy must be measured using the reference discharge test outlined in Article 4 Continuous discharge of the battery is required by repeating the reference micro-cycle at established power levels Discharge should cease at the end of the micro-cycle when the battery can no longer provide the required power or when mandated by the battery management system The reason for ending the test must be documented in the test report Continuous recording of the battery system's voltage is necessary during the test It is essential to log the test cycle values, the total number of micro-cycles, the energy supplied during discharge periods, and the energy recovered during regenerative braking The battery's embedded energy should be reported as the net energy yield, defined as the difference between the energy supplied and the energy recovered.
The battery management system can determine the end of discharge based on parameters such as ampere-hours, temperature, voltage, or other factors that ensure the battery's longevity and safety.
Energie embarquée de référence
After the initial conditioning of a new battery, the reference discharge test must be repeated a total of 10 times, with one test conducted each day to ensure the consistency of the measured capacity The net energy delivered during each of the 10 tests should be recorded, and the net energy provided during the final discharge must be documented and reported as the reference embedded energy.
Essais de durée de vie
The reference discharge test is essential for determining battery lifespan The battery should be discharged until 80% of its stored energy is utilized or until the end of the micro-cycle, where 80% of the energy is consumed Following this, the battery must be recharged, with the charging process starting within one hour after the discharge concludes Once the charging is complete, the next discharge should commence no later than one hour after the charging finishes.
NOTE Le commencement de la dộcharge peut ờtre retardộ de faỗon à correspondre aux conditions de travail du laboratoire d'essais.
The battery's embedded energy must be checked every 50 cycles using a reference discharge profile to assess its energy content and other parameters Continuous monitoring of the battery system's voltage is essential during this test to determine additional system parameters Furthermore, the total number of micro-cycles, along with the total energy supplied and returned to the battery, should be recorded and reported as the embedded energy at this stage of the lifespan testing program.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
The overall accuracy of controlled (or measured) values, relative to the specific (or actual) values, shall be within the following tolerances:
Power slew rate: ≤1 s from one value of steady power to the next.
Switching between power levels in the micro-cycle shall be timed such that the mid-point of the transition occurs at the point allocated for the transition.
The total duration of each complete micro-cycle shall be 360 s ± 1 s.
5.2.3 Determination of battery energy content
The battery energy content will be assessed using the reference test cycle outlined in clause 4, involving continuous testing through repeated basic current discharge micro-cycles at specified power levels The test concludes when the battery can no longer provide the required power or when the battery management system halts the discharge, with the reason for termination documented in the test records Throughout the test, a continuous record of the battery system voltage will be maintained Additionally, the test will document the cycle values used, the total number of micro-cycles, the total watt-hours (Wh) discharged, and the total Wh recovered during simulated regenerative braking.
The battery energy content shall be declared as the net Wh output i.e., the difference between the total Wh removed and the total Wh returned.
NOTE The battery management system may terminate on the basis of ampere-hours, temperature, voltage or for any other reason associated with battery longevity or safety.
After the initial conditioning of a new battery system, the reference test cycle must be conducted 10 times, with one cycle per day, to ensure consistent capacity measurements The net energy extracted during each of the 10 tests will be documented, and the net energy from the final test will be declared as the benchmark energy content.
The reference test cycle is essential for assessing battery life, involving a discharge until 80% of its benchmark energy is depleted or until the end of the micro-cycle Following this, the battery must be recharged within 1 hour of discharge completion, and the subsequent discharge should commence within 1 hour after the recharge is finished.
NOTE The start of discharge may be delayed in order to fit in with the normal working practices of the test laboratory.
Every 50 cycles, the battery energy content shall be determined using the benchmark test cycle This will establish the actual energy content of the battery and allow the measurement of other parameters During this test, a continuous record of battery system voltage shall be made so that other battery system parameters may be determined In addition, the total number of micro-cycles, the total Wh removed and the total Wh returned shall be recorded and declared as the battery energy content at this stage of the life test programme.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
NOTE Si nécessaire, le fabricant de batteries peut utiliser une procédure de conditionnement immédiatement après la fin de l'essai d'énergie embarquée de référence.
The lifespan test should be concluded when the supplied energy falls below 80% of the reference onboard energy The number of reference test cycles must be recorded and reported as the battery's lifespan.
NOTE Les intervalles entre les essais d’énergie embarquée peuvent être modifiés pour qu’une dizaine de ces essais soient effectués pendant la durée de vie anticipée de la batterie.
Détermination de la puissance maximale et de la résistance interne
The maximum available power is defined, for the purposes of this standard, as the power at which the current reduces the voltage across the terminals to two-thirds of the open-circuit voltage The values of maximum power and battery resistance must be calculated from voltage and current measurements taken during the embedded energy test, recording the voltage and current values at the end of stages 14 and beyond.
15 Pour les besoins de ce calcul, la résistance de décharge et la tension de circuit ouvert doivent être calculées en utilisant les différences de courant et de tension à ces paliers La résistance de décharge doit être admise comme linéaire entre un courant nul et la puissance maximale.
La résistance de la batterie est donnée par:
La tension de circuit ouvert est donnée par:
Le courant nécessaire pour faire diminuer la tension à 2/3 V oc est donné par: batt pk 3 oc
I = V et la puissance maximale par:
R batt est la résistance de batterie calculée;
V oc est la tension de circuit ouvert calculée de la batterie;
I pk est le courant maximal calculé à la puissance maximale;
P max est la puissance maximale calculée de la batterie.
La résistance calculée de la batterie, la tension de circuit ouvert calculée et la puissance maximale calculée de la batterie doivent être déclarées dans les résultats.
The key battery parameters are established based on the vehicle's requirements Accurately determining the true maximum power can overstrain certain battery components and is typically unnecessary.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
NOTE It is permissible for the battery manufacturer to utilise a conditioning procedure immediately after the completion of the full benchmark energy content test, if required.
The life test will conclude once the energy output drops below 80% of the reference energy content The total number of reference test cycles will be documented and reported as the battery's lifespan.
NOTE The intervals between the battery energy content tests may be modified to give approximately 10 of these tests during the anticipated lifetime of the battery.
5.2.6 Determination of maximum power and battery resistance
Maximum deliverable power is defined as the power level at which the current drawn reduces the battery terminal voltage to two-thirds of its open circuit value.
The maximum power value and battery resistance will be determined from voltage and current measurements taken during the battery energy content test in the life testing program This involves recording the voltage and current values at the conclusion of steps 14 and 15 For the calculation, the discharge resistance and open circuit voltage will be derived from the differences in current and voltage at these points, with the discharge resistance assumed to be linear between zero current and maximum power.
The battery resistance is given by :
The open circuit voltage is given by :
The current required to depress the voltage to 2/3 V oc is given by : batt pk 3 oc
I = V and the maximum power by :
R batt is the calculated battery resistance;
V oc is the calculated open circuit voltage of the battery;
I pk is the calculated peak current at maximum power;
P max is the calculated maximum power of the battery.
The calculated battery resistance, the calculated open circuit voltage and the calculated maximum battery power shall be declared in the results.
Important battery parameters are defined based on vehicle requirements Experimentally determining the true maximum power can lead to overstressing certain battery components and is generally unnecessary.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Essais de charge
5.2.7.1 Rendement de charge pendant l’utilisation normale
The charge efficiency must be calculated by recording the energy supplied and the energy returned to the battery during each discharge/charge cycle, or during selected discharge/charge cycles from the lifespan testing program The measurement of charge efficiency should account for the consumption associated with any battery management systems used Additionally, it should include the consumption from maintenance or equalization charges required during the lifespan testing program.
The battery's efficiency should be determined based on the energy supplied and the energy returned to the battery, and this should be reported during each capacity test throughout the lifespan testing program.
The charge efficiency can also be assessed for different states of charge, such as an 80% depth of discharge (DOD) However, separate tests will be required to establish these findings.
NOTE Si nécessaire, le rendement du chargeur peut aussi être mesuré durant cet essai, bien que cette mesure ne soit pas du domaine d’application de la présente norme.
Les essais pour déterminer l'aptitude de la batterie à accepter des charges rapides peuvent être réalisés sur des modules de la batterie complète.
Battery modules must be prepared similarly to a complete battery, with their embedded energy values confirmed The battery should be discharged to the end of a micro-cycle, representing 60% of the embedded energy value (40% state of charge), and then quickly recharged to 80% state of charge according to the manufacturer's instructions Following this, the battery must undergo a reference discharge test to fully evaluate the effectiveness of the rapid charge in restoring energy The rapid charging method, the energy supplied during this process, and the available energy must be reported.
The battery charge efficiency during normal recovery phases should be assessed by examining voltage and current values during the energy life measurement test Evaluations must include recording current and voltage during periods that simulate regenerative braking Additionally, conditions under which the current is reduced by the battery management system or testing equipment to prevent exceeding the battery's usage limits should be reported.
Essais de décharge partielle
Les essais pour mesurer les effets de décharge partielle peuvent être réalisés sur des modules de la batterie complète.
The battery or its modules must be discharged until reaching the end of a micro-cycle, which represents 20% of the stored energy (equating to 80% state of charge), and then recharged normally This test should be repeated 20 times, with one test cycle conducted each day Following this, the battery must undergo a capacity test as outlined in section 5.2.3 The capacity value obtained must be recorded and reported The capacity test may be repeated as necessary.
5 fois de suite afin d’évaluer s’il y a des effets de récupération de la capacité Dans ce cas, la capacité mesurée doit être enregistrée et déclarée après chaque essai de capacité.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
5.2.7.1 Charge efficiency during normal operation
Charge efficiency is determined by measuring the energy input and output during each discharge and charge cycle of the battery life testing program This calculation must account for losses from battery management systems, if applicable, as well as any losses incurred from maintenance or equalizing charges throughout the testing period.
Battery efficiency is determined by comparing the energy input to the battery with the energy output during each capacity test conducted throughout the life testing program.
The charge efficiency may be determined for discharge to other states of charge (e.g 80 % depth of discharge (DOD)), though separate tests will be required to establish these results.
NOTE If required, the efficiency of the charger may also be measured during this test, though the procedure for doing this is outside the scope of this standard.
Tests to determine the ability of the battery system to accept rapid charge may be made on sub-modules of the complete battery.
The battery sub-module must be prepared similarly to the complete battery, ensuring that the benchmark energy content is verified The battery should be discharged until it reaches the end of the micro-cycle, removing 60% of the benchmark energy content, resulting in a state of charge of 40%.
The battery must be quickly recharged to 80% State of Charge (SOC) following the manufacturer's guidelines The energy content will be evaluated by fully discharging the battery using a reference test cycle, and the efficiency of the rapid charging method will be analyzed based on the watt-hours (Wh) restored during the process Additionally, the energy content and the details of the rapid charging method will be reported.
The battery's charge acceptance during regenerative braking will be evaluated by monitoring voltage and current during benchmark capacity testing cycles This assessment focuses on periods that replicate regenerative braking conditions Additionally, it is essential to report any instances where the battery management system or test equipment reduced current to prevent exceeding the battery's operating voltage limits.
Tests to determine the effects of partial discharge testing may be made on sub-modules of the complete battery.
The battery or sub-module must be discharged to 80% state of charge (SOC), representing 20% of the benchmark capacity, and then recharged normally This process is to be repeated 20 times, with one test cycle conducted each day Following this, the battery will undergo the capacity test outlined in section 5.2.3, with the results recorded and declared To evaluate potential capacity recovery effects, the capacity test may be repeated up to five times, with each measured capacity documented and declared.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Cet essai peut être répété en utilisant un état de décharge de 50 %, si nécessaire.
Certain battery systems may require regular conditioning cycles if partial discharges occur frequently In such cases, it is essential to document the use of a battery conditioning cycle and record its details.
Plage de la tension d’utilisation
The minimum voltage during discharge and the maximum voltage during regeneration phases must be recorded for each micro-cycle during the battery capacity measurement test in the lifespan program (refer to section 5.2.3) These values should be reported as the operating voltage range for the respective micro-cycle.
Mesure de l’auto-décharge
Testing the self-discharge characteristics of battery systems can be conducted on complete battery modules In this scenario, any parasitic consumption impacting the battery must be simulated and adjusted according to the number of modules tested to ensure it accurately represents the effects on a full battery.
L’essai pour mesurer l’autodécharge, si nécessaire, doit être effectué immédiatement après les essais de capacité dans le programme des essais de durée de vie.
The battery should be fully charged under normal conditions and then allowed to rest, disconnected from any external power source, for 30 days At the end of this period, the battery's capacity must be measured using the battery capacity test (refer to section 5.2.3), and the results should be documented Any loss of capacity during this resting period should be reported as a loss due to self-discharge.
This test can be conducted during different rest periods and at various ambient temperatures The preferred rest periods are two days and five days, with ambient temperatures of -20 °C and +40 °C If the self-discharge test is performed at other temperatures, the battery's capacity at those temperatures must be previously established according to the tests outlined in sections 5.2.3 and 5.2.4.
Essais de perte de capacité en stockage
Some batteries may permanently lose capacity after a period of inactivity The details of the testing procedure to determine this permanent capacity loss are currently under investigation.
Modifications du cycle d’essais
Généralités
It is essential to establish a comprehensive battery testing program in advance between the battery supplier and the user This ensures that the appropriate number of batteries or battery modules can be prepared for the testing program.
Essais pour déterminer les effets du vieillissement sur la batterie
Battery modules tested can be utilized to assess the impact of aging on various performance metrics, including energy capacity, maximum power, internal resistance, charge efficiency across different conditions, partial discharge effects, operating voltage range, and self-discharge rates The established procedures must be followed, and results should be reported in accordance with the specified requirements.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
This test may be repeated using 50 % SOC as the depth of discharge, if required.
Battery systems that undergo continuous partial discharge testing may need regular conditioning cycles It is essential to declare the use of these conditioning cycles and document the details accordingly.
During the battery capacity tests in the life test program, it is essential to record the minimum voltage during discharge and the maximum voltage during simulated regenerative braking for each micro-cycle These recorded values will define the operating voltage range for that specific micro-cycle.
To evaluate the self-discharge characteristics of a battery system, tests can be conducted on sub-modules of the complete battery During these tests, any parasitic loads on the battery must be simulated and adjusted to accurately reflect those relevant to the full-sized battery.
The test to measure self-discharge, if required, shall be carried out immediately after the capacity tests in the life test programme.
The battery must be fully charged and left disconnected from any external power source for 30 days After this period, the capacity should be measured according to the battery capacity test (refer to section 5.2.3), and the results should be documented Any capacity loss observed will be attributed to self-discharge during the standing period.
This test may be carried out for other durations of stand and at other ambient temperatures.
The preferred alternative durations for testing are two days and five days, while the recommended ambient temperatures are −20 °C and +40 °C To conduct the self-discharge test at these temperatures, it is essential to first determine the battery's capacity by performing the tests outlined in sections 5.2.3 and 5.2.4 at the specified ambient conditions.
Certain batteries may suffer permanent capacity loss following a period of standing without use Details of the test procedure to determine this permanent loss are under consideration.
To ensure an effective battery test program, it is essential for the battery supplier and user to clearly define the testing requirements beforehand This collaboration allows for the proper preparation of the necessary number of batteries and sub-modules for the testing process.
5.3.2 Tests to determine effects of battery age
The life test program for batteries or sub-modules is designed to assess the impact of battery age on various performance metrics, including energy content, peak power, resistance, charge acceptance at different rates, partial discharge effects, operating voltage range, and self-discharge The established procedures will be followed, and the results will be reported in compliance with the specified requirements.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Essais pour déterminer les effets de la température ambiante
Battery modules tested can be utilized to assess the impact of temperature on battery lifespan, energy capacity, maximum power, internal resistance, charging efficiency across various conditions, partial discharge effects, operating voltage range, and self-discharge rates The specified procedures must be followed, and results should be reported in accordance with established requirements.
Généralités
Currently, very few traction batteries available or under development can continuously withstand extreme operating conditions without sustaining damage In such extreme conditions, the battery is safeguarded by its management system.
The purpose of the following tests is to identify the usage limits of the battery imposed by the Battery Management System (BMS) under conditions that the battery alone could not withstand This highlights the need for a precise and reliable interface between the management system and the vehicle's drive system, as even a few minutes of extreme use can lead to permanent damage to the battery.
Dộcharge continue à la puissance maximale dộlivrộe par la chaợne de traction
Introduction
It is feasible to operate the vehicle continuously at high power under various conditions A prime example of this usage includes ascending a long hill or towing another vehicle for an extended period, or even both simultaneously.
Procédure d’essai
The battery must be fully charged under normal conditions and then discharged at the maximum power specified by the driving system during the standard testing cycle Throughout the test, current and voltage should be continuously recorded The test should be halted once any limits set by the battery manufacturer are reached Additionally, the duration for which maximum power can be sustained, along with the power/time curve permitted by the battery management system, should be documented, especially if a reduced power discharge is allowed.
Recharge à puissance régénérative maximale en fonction de l’état de charge
Introduction
Normal city driving does not support high levels of regenerative power in a vehicle However, this may change when the vehicle is towed or used outside urban areas The most unfavorable scenario occurs when the battery is asked to accept maximum regenerative power while fully charged A sophisticated battery management system would prevent this situation by signaling and enforcing a reduction in regenerative power to the vehicle's driving system It is essential for the vehicle manufacturer to be informed about the interface requirements before conducting such tests.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
5.3.3 Tests to determine effects of ambient temperature
The life test program for batteries or sub-modules is essential for assessing the impact of temperature on various performance metrics, including battery life, energy capacity, peak power, resistance, charge acceptance across different rates, partial discharge effects, operating voltage range, and self-discharge rates The previously outlined procedures will be followed, and the results will be reported in compliance with established requirements.
Very few traction batteries currently available or under development will accept continuous extremes of operation without damage Under these conditions, the battery is protected by the
The Battery Management System (BMS) is designed to define the operational limits of a battery, particularly under conditions that the battery may not tolerate The tests conducted aim to uncover these limitations imposed by the BMS.
Accurate and reliable communication between the Battery Management System (BMS) and the vehicle system is crucial, as even a few minutes of extreme operation can lead to permanent battery damage.
6.2 Continuous discharge at maximum drive system power
It is possible to operate the vehicle continuously at high power in a number of conditions.
Examples of such operation would be prolonged hill climbing or prolonged towing of another vehicle (or both).
The battery must be fully charged and then discharged at the maximum power level specified for the reference test cycle Continuous recording of current and voltage is required, and the test will end once any manufacturer-imposed limits are reached Additionally, the test will document how long maximum power can be maintained and the power/time curve permitted by the Battery Management System (BMS) if discharge continues at a reduced power level.
6.3 Recharge at maximum regenerative power as a function of state of charge
In urban driving, vehicles typically cannot maintain high levels of regenerative power; however, this changes when towing or commuting to out-of-town locations The most challenging scenario occurs when the battery must accept maximum regenerative power while fully charged A well-designed battery management system (BMS) mitigates this risk by instructing the vehicle's drive system to lower regenerative power It is essential for the vehicle manufacturer to be informed of the necessary interfacing requirements prior to conducting such tests.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Procédure d’essai
The standard test cycle should be employed to discharge the battery to specific levels: 0%, 25%, 50%, 75%, or 100% Following this, the battery must undergo the maximum regenerative braking power of the standard cycle for 15 minutes Continuous recording of current, voltage, and temperature is essential throughout the test The test is considered complete when any driving system limit or battery manufacturer limit is reached.
During the test, it is essential to record the duration for which the maximum regenerative power can be sustained, as well as the power/time curve permitted by the battery management system, especially if a reduced power discharge is allowed to continue.
Essais thermiques
Cycle thermique
Batteries can endure thermal cycles under various conditions, including cooling of "hot" batteries, transitioning a vehicle from a garage to an environment with cold or hot ambient temperatures, and operating a vehicle that has been exposed to extreme temperatures in a garage.
Les modalités de l'essai sont à déterminer.
Basic current discharge micro-cycle
The basic current discharge micro-cycle is based on the Dynamic Stress Test (DST) established by the United States Advanced Battery Consortium (USABC), in turn based on the earlier
The Simplified Federal Urban Driving Cycle (SFUDS) test cycle analysis reveals the step durations and percentage powers for each step For an average discharge power of 3 kW, the micro-cycle must be adjusted to ensure that the peak power in step 15 is appropriately scaled.
The 20-step DST micro-cycle, featuring a peak power of 24 kW, is detailed in Table 1 below, with discharge powers represented as negative values Tolerances for this cycle are specified in section 5.2.2.
Table 1 – List of DST values for one micro-cycle, where the peak power is 24 kW
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
The values mentioned for regenerative power are those necessary to meet the DST power profile To prevent dangerous overloads, the actual power delivered to the battery may, in some cases, be restricted by the battery management system.
L'essai de décharge de référence consiste en la succession répétée des micro-cycles de référence jusqu’à ce que la batterie soit déchargée ou l’essai terminé pour une autre raison.
4.2 Ajustement en fonction de la performance de véhicule, si nécessaire
The energy consumption of a high-performance vehicle may exceed that of a lower-performance vehicle; however, due to traffic constraints, the difference in energy consumption is minimal during normal city use Battery and vehicle manufacturers can modify discharge tests to reflect the higher demands placed on the battery by high-performance vehicles To tailor the testing procedure for a specific vehicle type, the values for discharge power (level 15) and regenerative power (level 19) in the reference micro-cycle must be adjusted in magnitude, but not in duration, to accurately simulate the actual power delivered by the vehicle's traction system A battery designed for a high-performance vehicle will have increased power values, while the same battery for a more basic vehicle will have reduced values, with other power levels and timings remaining unchanged An example of an adapted micro-cycle for testing a high-performance vehicle battery, assuming a test mass of 1 ton, is provided in Table 2, which includes the maximum discharge power of the traction system.
100 kW et la puissance maximale de régénération est de 50 kW.
Tableau 2 – Liste des valeurs DST pour un micro-cycle pour un véhicule à performances élevées
4.3 Essai de sélection de la batterie
Choosing the right battery for testing is an iterative process that relies on the relationship between the battery supplier and the vehicle manufacturer, which becomes more critical during testing Initially, the vehicle manufacturer must define the power levels of the traction chain during discharge and regenerative braking Subsequently, the battery manufacturer should provide a representative battery sample for evaluation, utilizing a reference micro-cycle profile that may be adjusted to accurately reflect the actual capabilities of the traction chain in both discharge and regenerative braking scenarios.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
The regenerative power values mentioned are necessary to meet the DST power profile To avoid significant overcharging, the battery management system may restrict the actual power supplied to the battery in certain situations.
The reference test cycle consists of repeated micro-cycles until the battery is discharged or the test is terminated for some other reason.
Adjustment for vehicle performance, if required
High-performance vehicles often consume more energy than low-performance ones; however, in typical urban driving conditions, the difference in energy consumption is minimal due to traffic constraints To address the unique demands placed on batteries by high-performance vehicles, the battery testing procedure can be tailored to each vehicle, contingent upon an agreement between the battery and vehicle manufacturers This customization includes specific steps, such as maximum discharge power, to ensure accurate performance assessment.
The maximum regenerative power of the basic micro-cycle profile will be adjusted in magnitude to match the actual power capability of the vehicle's drive system, while the duration will remain unchanged For high-performance vehicles, the peak values of the battery system will be increased, whereas for low-performance vehicles, these values will be reduced The other steps in the micro-cycle will maintain their original duration For instance, a micro-cycle designed to test a battery in a high-performance vehicle with a test weight of one tonne demonstrates a maximum drive system power capability of 100 kW and a maximum regenerative power of 50 kW, as illustrated in Table 2.
Table 2 – List of DST values for one micro-cycle, adapted for a high performance vehicle
Battery screening test
Selecting the right battery for testing is an iterative process that relies on the collaboration between the battery supplier and the car manufacturer, with understanding improving as tests progress Initially, the vehicle manufacturer must assess the power requirements for the drive system during both driving and regenerative braking Subsequently, the battery manufacturer should provide a representative battery sample for evaluation, using a basic current discharge profile that may be adjusted to accurately reflect the drive system's power capabilities in both driving and regenerative braking scenarios.
The battery manufacturer must provide a battery management system that connects to the test bench or specify the limits for the battery under test A complete capacity test must be conducted on a representative sample to enable a calculated assessment of the vehicle's range post-test Tests should be repeated while maintaining the same power profile and using batteries of the same design but with different masses Additionally, a graph illustrating the vehicle's calculated range as a function of battery mass must be created.
This will enable the vehicle manufacturer and the battery manufacturer to assess the battery's suitability for the application by identifying its limiting factor before initiating a comprehensive testing program.
5.1 Sélection de la batterie et préparation pour les essais
A battery, including a management system and auxiliary components, must be prepared for testing according to the manufacturer's instructions It is essential to document the battery preparation procedures Compatibility among the various systems involved, such as the battery management system, vehicle powertrain, and laboratory test bench, should be thoroughly verified by all parties before testing begins During the test, the battery must be placed in an environment where air circulation and ambient temperature reflect the conditions experienced in a vehicle used in urban settings.
For battery selection, it is advised that the maximum weight should not exceed 30% of the vehicle's total weight when fully loaded, or that its capacity should not allow for a range greater than 150 km.
Battery preparation is crucial for the optimal performance of vehicles, but it can pose significant drawbacks for certain battery types For instance, batteries operating at high temperatures may require a heating period of 24 hours or more, while others, like fuel cells, necessitate heating before each use.
NOTE 3 La préparation des batteries pour des essais n’est pas une nouveauté; plusieurs cycles peuvent être effectués sur les éléments et batteries afin d’obtenir l’assurance d’une capacité convenable.
It is possible to conduct selection tests on battery modules, provided that the battery management system and thermal conditions are simulated These modules must have the same capacity as the complete battery and a nominal voltage of at least 12 V.
The battery must be fully charged according to the manufacturer's instructions at an ambient temperature of 25 °C Testing should be conducted at this temperature unless otherwise specified, and under the same air circulation conditions as if the battery were installed in the vehicle Air circulation must be maintained during discharge but not during charging The battery heating or cooling system should be activated if required by the battery management system When an external power source is used to supply energy to the battery management system, the energy consumed must be recorded and reported.
It is acceptable to use an average airflow over the battery instead of adjusting the airflow based on the vehicle's calculated speed For testing purposes, it is recommended to maintain a constant airflow rate that corresponds to an average speed of 30 km/h.
The battery manufacturer is required to provide a battery management system (BMS) for interfacing with the test bench, or to specify the limitations of the tested battery Comprehensive capacity tests must be performed on a representative sample to evaluate the vehicle's range through calculations post-test These tests should be repeated while maintaining a consistent power profile, utilizing batteries of the same design but varying in weight Additionally, a graph must be created to illustrate the vehicle's calculated range in relation to battery weight.
This process enables both the vehicle and battery manufacturers to evaluate the battery's compatibility with the application by identifying its power limiting size prior to initiating an extensive testing program.
Battery selection and preparation for test
To ensure accurate testing, a battery, along with its management system and auxiliaries, must be prepared according to the manufacturer's instructions and documented procedures It is crucial for all parties involved to verify the compatibility of control elements across the battery management system, vehicle drive system, and laboratory test bench prior to testing Additionally, the battery should be positioned to replicate the airflow and ambient temperature conditions typical of a vehicle operating in urban environments.
When selecting a battery, ensure that its maximum weight does not exceed 30% of the total laden vehicle weight, or opt for a battery capacity that allows for an anticipated range of up to 150 km.
Battery preparation can be a critical and recurring aspect of vehicle system operation, potentially posing a significant drawback for certain batteries For instance, batteries that function at high temperatures may necessitate an initial heat-up period of 24 hours or longer, while others, akin to fuel cells, might require a "warm-up" phase before each use.
NOTE 3 Preparation of batteries for test is not new; cells and batteries may be conditioned for a number of cycles to ensure that an acceptable capacity is being delivered.
Screening tests on battery sub-units are permissible if the battery management system and thermal conditions are accurately simulated The sub-unit being tested must match the full battery's capacity and have a nominal voltage of at least 12 V.
Battery testing
Test procedure
The battery system must be fully charged at an ambient temperature of 25 °C, following the manufacturer's guidelines Testing should occur at this temperature and under typical airflow conditions similar to those in a vehicle Airflow must be maintained during discharge but not during charging If necessary, battery heating or cooling powered by the battery system should be operational Additionally, any energy consumed from an external power source for the battery management system must be recorded and reported.
It is permissible to utilize an average airflow over the battery instead of adjusting the flow based on the calculated vehicle speed For testing purposes, it is advisable to maintain a constant airflow rate that aligns with an average vehicle speed of 30 km/h.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
La précision générale de valeurs contrôlées (ou mesurées), relatives aux valeurs spécifiées
(ou réelles), doit être entre les tolérances suivantes:
Puissance: ±2 % de la valeur exigée
Temps: ±1 % de la valeur exigée
Taux de variation de puissance: ≤1 s d’une valeur de puissance établie à l’autre.
The transition from one power level to another during the micro-cycle should be executed in such a way that the midpoint of the effective transition aligns with the specified point for the transition.
La durée totale pour chaque micro-cycle complet doit être de 360 s ± 1 s.
5.2.3 Détermination de l’énergie embarquée de la batterie
The battery's embedded energy must be measured using the reference discharge test outlined in Article 4 Continuous discharge of the battery should occur by repeating the reference micro-cycle at established power levels Discharge should cease at the end of the micro-cycle when the battery can no longer provide the required power or when mandated by the battery management system The reason for ending the test must be documented in the test report Continuous recording of the battery system's voltage is required during the test The test cycle values, total number of micro-cycles, energy supplied during discharge periods, and energy recovered during regenerative braking must be recorded and reported The battery's embedded energy should be declared as the net energy yield, which is the difference between the energy supplied and the energy recovered.
The battery management system can determine the end of discharge based on parameters such as ampere-hours, temperature, voltage, or other factors that ensure the battery's longevity and safety.
After the initial conditioning of a new battery, the reference discharge test must be repeated a total of 10 times, with one test conducted each day to ensure the consistency of the measured capacity The net energy delivered during each of the 10 tests should be recorded, and the net energy provided during the final discharge must be documented and reported as the reference embedded energy.
5.2.5 Essais de durée de vie
The reference discharge test is essential for determining battery lifespan The battery should be discharged until 80% of its stored energy is utilized or until the end of the micro-cycle, which also uses 80% of the energy Following this, the battery must be recharged, with the charging process starting within one hour after the discharge ends Once the charging is complete, the next discharge should commence no later than one hour after the charging finishes.
NOTE Le commencement de la dộcharge peut ờtre retardộ de faỗon à correspondre aux conditions de travail du laboratoire d'essais.
The battery's embedded energy must be checked every 50 cycles using a reference discharge profile to assess its energy content and other parameters Continuous monitoring of the battery system's voltage is essential during this test, as it helps determine additional system parameters Furthermore, the total number of micro-cycles, along with the total energy supplied and returned to the battery, should be recorded and reported as the embedded energy at this stage of the lifespan testing program.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Maximum allowable deviations
The overall accuracy of controlled (or measured) values, relative to the specific (or actual) values, shall be within the following tolerances:
Power slew rate: ≤1 s from one value of steady power to the next.
Switching between power levels in the micro-cycle shall be timed such that the mid-point of the transition occurs at the point allocated for the transition.
The total duration of each complete micro-cycle shall be 360 s ± 1 s.
Determination of battery energy content
The battery energy content is measured using the reference test cycle outlined in clause 4, involving continuous testing through repeated basic current discharge micro-cycles at specified power levels Testing concludes when the battery can no longer deliver the required power or when the battery management system terminates the discharge, with the reason for termination documented in the test records Throughout the test, a continuous record of the battery system voltage is maintained Key data recorded includes the test cycle values, total number of micro-cycles, watt-hours (Wh) discharged, and Wh returned during simulated regenerative braking.
The battery energy content shall be declared as the net Wh output i.e., the difference between the total Wh removed and the total Wh returned.
NOTE The battery management system may terminate on the basis of ampere-hours, temperature, voltage or for any other reason associated with battery longevity or safety.
Benchmark energy content
After the initial conditioning of a new battery system, the reference test cycle must be conducted 10 times, with one cycle per day, to ensure consistent capacity measurements The net energy extracted during each of the 10 tests will be documented, and the net energy from the final test will be declared as the benchmark energy content.
Life testing
The reference test cycle is essential for assessing battery life, involving discharging the battery until 80% of its benchmark energy is depleted or until the end of the micro-cycle Following this, the battery must be recharged within one hour of discharge completion, and the subsequent discharge should commence within one hour after the recharge is finished.
NOTE The start of discharge may be delayed in order to fit in with the normal working practices of the test laboratory.
Every 50 cycles, the battery energy content shall be determined using the benchmark test cycle This will establish the actual energy content of the battery and allow the measurement of other parameters During this test, a continuous record of battery system voltage shall be made so that other battery system parameters may be determined In addition, the total number of micro-cycles, the total Wh removed and the total Wh returned shall be recorded and declared as the battery energy content at this stage of the life test programme.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
NOTE Si nécessaire, le fabricant de batteries peut utiliser une procédure de conditionnement immédiatement après la fin de l'essai d'énergie embarquée de référence.
The lifespan test should be concluded when the supplied energy falls below 80% of the reference onboard energy The number of reference test cycles must be recorded and reported as the battery's lifespan.
NOTE Les intervalles entre les essais d’énergie embarquée peuvent être modifiés pour qu’une dizaine de ces essais soient effectués pendant la durée de vie anticipée de la batterie.
5.2.6 Détermination de la puissance maximale et de la résistance interne de la batterie
The maximum available power is defined, for the purposes of this standard, as the power at which the current reduces the voltage at the terminals to two-thirds of the open-circuit voltage The values of maximum power and battery resistance must be calculated from voltage and current measurements taken during the embedded energy test by recording the voltage and current values at the end of stages 14 and.
15 Pour les besoins de ce calcul, la résistance de décharge et la tension de circuit ouvert doivent être calculées en utilisant les différences de courant et de tension à ces paliers La résistance de décharge doit être admise comme linéaire entre un courant nul et la puissance maximale.
La résistance de la batterie est donnée par:
La tension de circuit ouvert est donnée par:
Le courant nécessaire pour faire diminuer la tension à 2/3 V oc est donné par: batt pk 3 oc
I = V et la puissance maximale par:
R batt est la résistance de batterie calculée;
V oc est la tension de circuit ouvert calculée de la batterie;
I pk est le courant maximal calculé à la puissance maximale;
P max est la puissance maximale calculée de la batterie.
La résistance calculée de la batterie, la tension de circuit ouvert calculée et la puissance maximale calculée de la batterie doivent être déclarées dans les résultats.
The key battery parameters are established based on the vehicle's requirements Accurately determining the true maximum power can overstrain certain battery components and is typically unnecessary.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
NOTE It is permissible for the battery manufacturer to utilise a conditioning procedure immediately after the completion of the full benchmark energy content test, if required.
The life test will conclude when the energy output drops below 80% of the reference energy content, with the total number of reference test cycles documented and reported as the battery's lifespan.
NOTE The intervals between the battery energy content tests may be modified to give approximately 10 of these tests during the anticipated lifetime of the battery.
Determination of maximum power and battery resistance
Maximum deliverable power refers to the level of power at which the current drawn reduces the battery terminal voltage to two-thirds of its open circuit value.
The maximum power value and battery resistance will be determined from voltage and current measurements taken during the battery energy content test in the life testing program This involves recording voltage and current values at the conclusion of steps 14 and 15 The discharge resistance and open circuit voltage will be calculated based on the differences in current and voltage at these points, with the assumption that discharge resistance is linear between zero current and maximum power.
The battery resistance is given by :
The open circuit voltage is given by :
The current required to depress the voltage to 2/3 V oc is given by : batt pk 3 oc
I = V and the maximum power by :
R batt is the calculated battery resistance;
V oc is the calculated open circuit voltage of the battery;
I pk is the calculated peak current at maximum power;
P max is the calculated maximum power of the battery.
The calculated battery resistance, the calculated open circuit voltage and the calculated maximum battery power shall be declared in the results.
Important battery parameters are defined based on vehicle requirements Experimentally determining the true maximum power can lead to overstressing certain battery components and is generally unnecessary.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
5.2.7.1 Rendement de charge pendant l’utilisation normale
The charge efficiency must be calculated by recording the energy supplied and the energy returned to the battery during each charge/discharge cycle, or during selected discharge/charge cycles of the lifespan testing program The measurement of charge efficiency should account for the consumption associated with any battery management systems used Additionally, it should include the consumption from maintenance or equalization charges required during the lifespan testing program.
The battery's efficiency should be determined based on the energy supplied and the energy returned to the battery, and this should be reported during each capacity test throughout the lifespan testing program.
The charge efficiency can also be assessed for different states of charge, such as an 80% depth of discharge (DOD) However, separate tests will be required to establish these findings.
NOTE Si nécessaire, le rendement du chargeur peut aussi être mesuré durant cet essai, bien que cette mesure ne soit pas du domaine d’application de la présente norme.
Les essais pour déterminer l'aptitude de la batterie à accepter des charges rapides peuvent être réalisés sur des modules de la batterie complète.
Battery modules must be prepared similarly to a complete battery, with their embedded energy value confirmed The battery should be discharged to the end of a micro-cycle, representing 60% of the embedded energy value (40% state of charge), and then quickly recharged to 80% state of charge according to the manufacturer's instructions Following this, the battery must undergo a reference discharge test to fully evaluate the effectiveness of the rapid charging process The rapid charging method, the energy supplied to the battery during this process, and the available energy must be documented.
The battery charge efficiency during normal recovery phases should be assessed by monitoring voltage and current values during the energy life measurement test Evaluations must include recording current and voltage during periods that simulate regenerative braking Additionally, conditions under which the current is reduced by the battery management system or testing equipment to prevent exceeding battery usage limits should be reported.
Les essais pour mesurer les effets de décharge partielle peuvent être réalisés sur des modules de la batterie complète.
The battery or its modules must be discharged to the end of the micro-cycle, representing 20% of the stored energy (equating to 80% state of charge), and then recharged normally This test should be repeated 20 times, with one test cycle conducted each day Following this, the battery must undergo a capacity test as outlined in section 5.2.3 The obtained capacity value must be recorded and reported The capacity test may be repeated as necessary.
5 fois de suite afin d’évaluer s’il y a des effets de récupération de la capacité Dans ce cas, la capacité mesurée doit être enregistrée et déclarée après chaque essai de capacité.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Charging tests
5.2.7.1 Charge efficiency during normal operation
Charge efficiency is determined by measuring the energy input and output during each discharge and charge cycle in the battery life testing program This calculation must account for losses from battery management systems, if applicable, as well as any losses incurred from maintenance or equalizing charges throughout the testing period.
Battery efficiency is determined by comparing the energy input to the battery with the energy output during each capacity test conducted throughout the life testing program.
The charge efficiency may be determined for discharge to other states of charge (e.g 80 % depth of discharge (DOD)), though separate tests will be required to establish these results.
NOTE If required, the efficiency of the charger may also be measured during this test, though the procedure for doing this is outside the scope of this standard.
Tests to determine the ability of the battery system to accept rapid charge may be made on sub-modules of the complete battery.
The battery sub-module must be prepared similarly to the complete battery, ensuring that the benchmark energy content is verified The battery should be discharged until it reaches the end of the micro-cycle, removing 60% of the benchmark energy content, resulting in a state of charge of 40%.
The battery must be quickly recharged to 80% State of Charge (SOC) following the manufacturer's guidelines The energy content will be evaluated by fully discharging the battery using a reference test cycle, and the efficiency of the rapid charging process in restoring energy will be analyzed Additionally, the rapid charging method, the watt-hours (Wh) returned to the battery, and the overall energy content will be reported.
The battery's charge acceptance during regenerative braking will be evaluated by monitoring voltage and current during benchmark capacity testing cycles This assessment focuses on periods that replicate regenerative braking conditions Additionally, it is essential to report any instances where the battery management system or test equipment reduced current to prevent exceeding the battery's operating voltage limits.
Partial discharge testing
Tests to determine the effects of partial discharge testing may be made on sub-modules of the complete battery.
The battery or sub-module must be discharged to 80% state of charge (SOC), representing 20% of the benchmark capacity, and then recharged normally This process is to be repeated 20 times, with one test cycle conducted each day Following this, the battery will undergo the capacity test outlined in section 5.2.3, with the results recorded and declared To evaluate potential capacity recovery effects, the capacity test may be repeated up to five times, with each measured capacity documented and declared.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
Cet essai peut être répété en utilisant un état de décharge de 50 %, si nécessaire.
Certain battery systems may require regular conditioning cycles if partial discharges occur frequently In such cases, it is essential to document the use of a battery conditioning cycle and record its details.
5.2.9 Plage de la tension d’utilisation
The minimum voltage during discharge and the maximum voltage during regeneration phases must be recorded for each micro-cycle during the battery capacity measurement test in the lifespan program (refer to section 5.2.3) These values should be reported as the operating voltage range for the respective micro-cycle.
Testing the self-discharge characteristics of battery systems can be conducted on complete battery modules In this scenario, any parasitic consumption impacting the battery must be simulated and adjusted according to the number of modules tested to ensure it accurately represents the effects on a full battery.
L’essai pour mesurer l’autodécharge, si nécessaire, doit être effectué immédiatement après les essais de capacité dans le programme des essais de durée de vie.
The battery should be fully charged under normal conditions and then allowed to rest, disconnected from any external power source, for 30 days At the end of this period, the battery's capacity must be measured using the battery capacity test (refer to section 5.2.3), and the results should be documented Any loss of capacity during this resting period should be reported as a loss due to self-discharge.
This test can be conducted during different rest periods and at various ambient temperatures The preferred rest periods are two days and five days, with ambient temperatures ranging from -20 °C to +40 °C If the self-discharge test is performed at alternative temperatures, the battery's capacity at those temperatures must be previously determined according to the tests outlined in sections 5.2.3 and 5.2.4.
5.2.11 Essais de perte de capacité en stockage
Some batteries may permanently lose capacity after a period of inactivity The details of the testing procedure to determine this permanent capacity loss are currently under investigation.
It is essential to establish a comprehensive battery testing program in advance between the battery supplier and the user This ensures that the appropriate number of batteries or battery modules can be prepared for the testing program.
5.3.2 Essais pour déterminer les effets du vieillissement sur la batterie
Battery modules tested can be utilized to assess the impact of aging on various performance metrics, including energy capacity, maximum power, internal resistance, charge efficiency across different conditions, partial discharge effects, operating voltage range, and self-discharge rates The established procedures must be followed, and results should be reported in accordance with the specified requirements.
LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
This test may be repeated using 50 % SOC as the depth of discharge, if required.
Battery systems that undergo continuous partial discharge testing may need regular conditioning cycles It is essential to document the use of these conditioning cycles and record the relevant details.
Operating voltage range
During the battery capacity tests in the life test program, it is essential to record the minimum voltage during discharge and the maximum voltage during simulated regenerative braking for each micro-cycle These recorded values will be declared as the operating voltage range for that specific micro-cycle.
Measurement of self discharge
To evaluate the self-discharge characteristics of a battery system, tests can be conducted on sub-modules of the complete battery During these tests, any parasitic loads on the battery must be simulated and adjusted to accurately reflect those relevant to the full-sized battery.
The test to measure self-discharge, if required, shall be carried out immediately after the capacity tests in the life test programme.
The battery must be fully charged and left disconnected from any external power source for 30 days After this period, the capacity should be assessed using the battery capacity test (refer to section 5.2.3), and the findings should be documented Any capacity reduction observed will be attributed to self-discharge during the storage period.
This test may be carried out for other durations of stand and at other ambient temperatures.
The preferred alternative durations for testing are two days and five days, while the recommended ambient temperatures are −20 °C and +40 °C Before conducting the self-discharge test at these temperatures, it is essential to determine the battery's capacity by performing the tests outlined in sections 5.2.3 and 5.2.4 at the specified ambient conditions.
Capacity loss testing
Certain batteries may suffer permanent capacity loss following a period of standing without use Details of the test procedure to determine this permanent loss are under consideration.