Technical manual section 02

PLASTIC Table 1 Plastic Test Reference 4.1 Raw Material Resin 4.1.1 Metal Impurities Leach Method 4.2 Plastic Containers 4.2.1 Acid Resistance Tests 4.3.3 Bushing Impact Resistance 4.

BCI Battery Technical Manual

FEB02

Current Revision: 2002-02

RECOMMENDED TEST PROCEDURES FOR BATTERY MATERIALS

TABLE OF CONTENTS

1 Material Requirements 3

2 Standard Specifications for Pig Lead 3

3 Hard Rubber 4

3.1 Rubber Containers 4

3.2 Rubber Covers 6

4 Plastic 6

4.1 Raw Material Resin 6

4.2 Plastic Containers 8

4.2.1 Acid Resistance Tests 9

4.2.2 Impact Resistance 11

4.2.3 Bulge Test 13

4.2.4 Electrical Breakdown` 13

4.2.5 Adhesion 14

4.2.6 Tensile Pull Test for Side Terminals 14

4.2.7 Torque Test for Side Terminals 16

4.2.8 Leakage Test for Side Terminals 17

4.3 Plastic Covers 18

4.3.1 Acid Resistance 18

4.3.2 Impact Resistance 18

4.3.3 Bushing Impact Resistance 19

4.3.4 Bushing/Stud Torque Test 19

4.3.5 Adhesion 20

5 Separator Test Methods 20

5.1 Test I – Ohmic Resistance 20

5.1.1 Procedure IA – Pre-Treatment 20

5.1.2 Procedure 1B – Ohmic Resistance 21

5.2 Test II – Dimension Measurement 30

5.2.1 Procedure IIA – Height and Width 30

5.2.2 Procedure IIB – Squareness 31

5.2.3 Procedure IIC – Backweb Thickness 31

5.2.4 Procedure IID – Overall Thickness 32

5.3 Test III – Determination of Volume Porosity 34

5.4 Test IV – Determination of Pore Size Distribution 35

5.5 Test V – Analyses for Impurities and Acid Extractables 36

5.5.1 Procedure VA – Acid Extraction 36

5.5.2 Procedure VB – Chloride Analysis 37

5.5.3 Procedure VC – Metal Analysis 39

5.6 Test VI – Stiffness Measurement 39

5.7 Test VII – Determination of Puncture Resistance 41

5.7.1 Procedure VIIA – Globe Tester 41

5.7.2 Procedure VIIB – GNB (“Gould”) Puncture Tester 43

5.8 Test VIII – Wetting Properties 44

5.8.1 Procedure VIIIA – Acid Flotation Method 44

5.8.2 Procedure VIIIB – Acid Drop Absorption Method 45

5.8.3 Procedure VIIIC – Dry Charge Process Simulation 45

6 Sealing Compound 46

7 Electrolyte 47

8 Intercell Connectors 48

9 Post Straps 48

10 Plates 48

11 Handles 48

12 Tapered Terminal Posts 48

13 Side Terminals 49

1 MATERIAL REQUIREMENTS

1.1 Materials Not Described

Unless otherwise detailed in this specification, all material used in the construction of

batteries shall conform to best commercial practices Active material, grid alloy or

miscellaneous lead parts smelted from other batteries must be refined prior to subsequent

use in new batteries

2 STANDARD SPECIFICATIONS FOR PIG LEAD

ASTM Designation B29-79(84) This standard covers pure lead of two grades for use in

producing oxide for active material or alloying with various materials for grid alloys The

chemical requirements are shown in Table I

Antimony, Arsenic, Tin (Together, max) 002 002

2.1 BCI Standard Reference Materials

Standard Reference Materials have been developed by the BCI Technical Committee for use

by lead and battery manufacturers Materials exist for 1, 3, and 6% antimony as well as

lead-calcium-aluminum alloys with and without tin The analyses of these materials are shown in

Zinc <.0003 <.0003 <.0003 <.0005 <.0003 These materials are available from RSR Corporation, 1111 West Mockingbird Lane, Dallas,

TX 75257, Attn: R D Prengaman

3 HARD RUBBER

The containers when tested in accordance with ASTM procedure designated D639-60-T,

entitled “Tentative Methods of Testing Battery Containers Made From Hard Rubber or

Equivalent Materials” revised 1960 shall meet the following chemical, electrical and physical

requirements:

3.1.1 Manganese (maximum) 0.003%

3.1.2 Iron (maximum) 0.3%

3.1.3 Acid Resistance

(a) Exact Days of Immersion 28 days

(b) Change in Dimensions (maximum) 2%

(c) Change in Weight (maximum) 35 mil per sq inch

(35 mil per 6.45 cm2) (d) Acid Penetration (maximum) 1/64 inch (.40 mm)

3.1.4 Impact Resistance

3.1.4.1 2.0 lb ± 0.05 lb (907 g ± 23) Solid Steel Ball shall be used Impact Points shall be as shown

on Figure A First impact point choice is exactly at H/2, however, if embossed letters, design

bands, etc interfere, the impact point may be between H/3 and H/2, at a point of minimum wall thickness (Note that impact point is always on the center line of the cell)

3.1.4.2 Number of Points to be impacted, as shown on Figure A

Figure A Impact Points for Various Configurations

3.1.4.3 Two averages will be compared with the following values, as well as the lowest single value

for each span The short span will be averaged (12 values in the case of a 12V “S”

assembly), and the long spans will be averaged (2 values in the case of a 12V “S” assembly) The following impact values must be met:

Minimum Impact Battery Service Resistance

1 6V and 12V passenger 12 in.-lb Average for short spans

car and light 12 in.-lb Average for long spans commercial plus 30H No impact value below

2 6V and 12V heavy 20 in.-lb average for short spans

duty commercial motor 20 in.-lb average for long spans coach and bus except No impact value below

30H and 30 HR 16 in.-lb

3.1.5 Bulge Test

(a) Water Temperature 160°F ± 2.0°F (71.1°C ± 1.1°C)

(b) Bulge Characteristics No value greater than 070 in (1.78 mm) 3.1.5.1 Hot-Cold Cycles

No failures permitted on 10 cycles

3.1.6 Electrical Breakdown Test

(a) Test voltage shall be 100V per mil thickness based on minimum thickness of container as

specified in the container design drawing, and not to exceed a maximum of 30,000V

(alternating peak voltage) applied between the electrodes

(b) No failures permitted in the sample lot (See Tech Con Rec.)

Chemical, physical, electrical and compound adhesion requirements shall be the same for

covers as for containers

4 PLASTIC

Table 1

Plastic Test Reference

4.1 Raw Material Resin 4.1.1 Metal Impurities (Leach Method)

4.2 Plastic Containers 4.2.1 Acid Resistance Tests

4.3.3 Bushing Impact Resistance 4.3.4 Bushing/Stud Torque Test

Physical tests should be done on components no less than twenty-four (24) hours after

molding at room temperature

4.1 Raw Material Resin

4.1.1 Metal Impurities (Leach Method) Acid Reflux Analysis

4.1.1.1 Scope

This procedure provides a method for extracting acid soluble contaminants from

polypropylene molding resin by refluxing in sulfuric acid followed by analysis for metallic

impurities

4.1.1.2 Apparatus

4.1.1.2.1 250 ml Erlenmeyer flask with standard 24/40 ground glass joint

4.1.1.2.2 Reflux condenser with joint

4.1.1.2.3 Thermostat-controlled hot plate

4.1.1.2.4 Balance capable of weighing to an accuracy of ± 0.025% of applied load

4.1.1.2.5 Sulfuric acid (1.265 sp gr 80/80) – J T Baker, Trace Metal Analytical Grade or equivalent

4.1.1.2.6 Deionized Water

4.1.1.2.7 Scissors

4.1.1.2.8 500 ml Volumetric flask

4.1.1.2.9 Filter unit with 0.45 micron membrane

4.1.1.2.10 Spectrometer-ICP (Inductively Coupled Plasma), AA (Atomic Absorption) or equivalent 4.1.1.3 Procedure

4.1.1.3.1 Accurately weigh 10.0 g ± 0.1 g of clean (Deionized Water rinsed), dried polypropylene resin

material; either pellets or molded parts (molded parts should be cut into approximately 0.25

cm (0.1 in.) cubes) Sample to be dried at 100ºC - 115ºC (212°F – 239°F) for one hour 4.1.1.3.2 Transfer the weighed material to the 250 Erlenmeyer flask and add 100 ml of 1.265 sp gr

80/80 sulfuric acid

4.1.1.3.3 Attach reflux condenser, mount on hot plate, heat rapidly to boil and adjust rate to one drop

per second

4.1.1.3.4 Prepare one (1) blank (control sample), reflux assembly, as noted above (4.1.1.3.2-3) without

polypropylene molded resin

4.1.1.3.5 Both samples should be boiled for five (5) hours and allowed to cool to room temperature 4.1.1.3.6 Filter solutions through the filter unit

4.1.1.3.7 These extracts are now ready for analysis

4.1.1.3.8 Quantitative elemental analysis should be performed in accordance with the ICP

manufacturer’s recommendations using the standards and prepared samples described above Alternative methods such as atomic absorption or x-ray fluorescence may be

substituted in the absence of an ICP

4.1.2 Accelerated Heat Aging (Molded Plaques) Oven Oxidation Test

4.1.2.1 Scope

This procedure provides a method to determine the resistance of polypropylene to

embrittlement by high temperature (oxidation) exposure This test provides insight on long term thermal stability of a polypropylene battery container and cover

4.1.2.2 Apparatus

4.1.2.2.1 Forced draft oven, capable of maintaining prescribed temperature within ±3ºC The oven

must be designed to allow substantial unobstructed circulation of air around test specimens placed in the oven

4.1.2.2.2 Temperature measuring device – thermometer, copper constantan (Type T) thermocouple

and potentiometer, or other suitable device capable of measuring the temperature to ±3ºC 4.1.2.2.3 Micrometer or other device suitable for measuring the test specimen thickness to the nearest

.02 mm or 001 in

4.1.2.2.4 Miscellaneous cutting tools for preparation of the test specimen

4.1.2.3 Procedure

4.1.2.3.1 The test specimen to be used is to be a 1.524 mm ± 0.050 mm (0.060 in ± 0.002 in) thick

molded plaque cut approximately 38.1 mm (1.5”) in length by 50.8 mm (2”) in width The test specimen must be free of air inclusions and foreign materials (injection molded preferred) Samples must also be free of rough edges for “fuzz” generated during the process of cutting the test specimen

4.1.2.3.2 All test specimens are to be coded for identification purpose

4.1.2.3.3 Record the following information concerning each test specimen:

(a) Polymer type, color, vendor and lot number

(b) Location of test specimen in the oven

(c) Oven temperature

(d) Date that the test specimen was placed into the oven

4.1.2.3.4 Suspend the test specimens in a clean oven in a suitable arrangement to allow at least a ½

inch space between each test specimen There shall be no contact between the test

specimens or between the test specimen and the metal surface of the oven

4.1.2.3.5 The test shall be conducted at a temperature of 149ºC ± 3ºC (300º ± 5ºF)

4.1.2.3.6 Test specimen to be visually inspected every twenty-four (24) hours for evidence of the

following:

(a) Embrittlement (cracking or crumbling of the test specimen) Note: This phenomenon usually occurs first at the thinnest cross-section of the test specimen and is the most common type of failure mode

(b) Melting of the test specimen

(c) A pronounced color change of the test specimen by a comparison to a sample from the original plaque retained in darkness at room temperatures (The date and degree of such an occurrence should be noted; however the test should not be terminated)

4.1.2.3.7 Criterion for termination of the test shall be the occurrence of embrittlement and/or melting of

the test specimen

4.1.2.3.8 Compute the total days that each test specimen was maintained at the test temperature

before the failure occurred Record this total as the final test result

4.1.2.3.9 The report of test results shall include the following:

(a) Polymer type, color, vendor and lot number

(b) Oven temperature maintained during test

(c) Date that the test specimen was placed into the oven

(d) The failure mode (embrittlement and/or melting)

(e) Total days to failure of the test specimen

4.2 Plastic Containers

4.2.1 Acid Resistance Tests

4.2.1.1 Scope

The following tests shall be performed on container samples to determine their resistance to sulfuric acid solutions:

(a) Acid Absorption Test

(b) Material Deterioration Test

(c) Dimensional Change Test

4.2.1.2 Apparatus

4.2.1.2.1 Reagent grade sulfuric acid – 1.300 ± 005 sp gr 80/80

4.2.1.2.2 Cutting tools

4.2.1.2.3 Mild detergent

4.2.1.2.4 Weighing scale (accuracy to 0.001 g.)

4.2.1.2.5 Caliper or Micrometer, accurate to 0.02 mm (0.001 in.)

4.2.1.2.6 Circulating air oven, temperature controllable at 65ºC ± 1ºC (150ºF ± 2ºF)

4.2.1.3 Procedure

4.2.1.3.1 Material samples shall be cut from flat areas and have four (4) cut sides

4.2.1.3.2 Material samples shall not include gates, partition ribs, logos, nameplates or other

nonconformities

4.2.1.3.3 Material samples shall consist of 26 sq cm (4 sq in.) or as large as possible without

including the items mentioned in 4.2.1.3.2

4.2.1.3.4 Material samples shall be cut to the specified dimensions (Ref Figure B) The cut edges

shall be essentially perpendicular to the flat surface of the sample, free of saw marks, nicks, grooves or ragged edges

Care shall be taken to insure that the flat surfaces of the samples are not scratched or damaged and that the samples are not overheated or mechanically damaged during

preparation of the sample

4.2.1.3.5 Samples shall be washed clean with a mild detergent and water solution and then rinsed with

water and air dried for at least 24 hours before pretest measurements are taken

Figure B

4.2.1.3.6 Measure to the nearest 0.02 mm (0.001 Inch) and record the length and width of the plane

surface of the sample at all locations as shown in Figure B

4.2.1.3.7 Measure to the nearest 0.02 mm (0.001 inch) and record the thickness of the sample at the

four (4) locations as shown in Figure B

4.2.1.3.8 Measurements specified in 4.2.1.3.6-7 shall be recorded and identified as shown in Figure B

4.2.1.3.9 Weigh the sample and record the weight to the nearest milligram (0.001 g)

4.2.1.3.10 Samples should not exhibit the following conditions before testing: cracks, blisters, pitting,

swelling or discoloration

4.2.1.3.11 All of the tests specified within the SCOPE shall be performed concurrently on the same

sample

4.2.1.3.12 Completely immerse the weighed and measured sample in a glass container filled with the

sulfuric acid solution The sample must be held beneath the surface of the liquid

4.2.1.3.13 Cover the container tightly to prevent evaporation

4.2.1.3.14 Place the container with the sample in a circulating-air oven with the temperature controlled

at 65ºC ± 1ºC (150ºF ± 2ºF) for 28 days

4.2.1.3.15 Remove the container with the sample after 28 days and allow to cool to room temperature 4.2.1.3.16 Remove the sample and rinse in running tap water to wash off the sulfuric acid solution and

dry the surface of the sample

4.2.1.3.17 Examine the sample and record evidence of material deterioration with respect to the

conditions specified in paragraph 4.2.1.3.10 or other signs of material deterioration

4.2.1.3.18 Weigh the sample in accordance with paragraph 4.2.1.3.9

4.2.1.3.19 Measure the width, length and the thickness of the sample in accordance with paragraph

4.2.1.3.21 Calculate the change of weight percentage as follows:

Change of Weight Percentage = 100((WA-WB)/WB), where WB = weight of sample before the test in milligrams and WA = weight of sample after the test in milligrams

4.2.1.3.22 The test report should include the following:

The average, reported to the nearest 0.1 percent, of the two width dimension change

percentages calculated in paragraph 4.2.1.320

The average, reported in the nearest 0.1 percent, of the four thickness dimension change percentages calculated in 4.2.1.3.20

Change of weight percentage calculated in paragraph 4.2.1.3.21, reported to the nearest 0.1 percent

Evaluation of the condition of the sample before and after the test with respect to each of the conditions of paragraph 4.2.1.3.10

4.2.2.2.2 Cold box capable of maintaining -18ºC (0ºF)

4.2.2.2.3 Measuring device, 0-100 cm or 0-36 in

4.2.2.3 Procedure

4.2.2.3.1 To be free fall tested on a container at –18ºC ± 1ºC (0ºF ± 2ºF) This procedure can be used

at other temperatures providing the temperature used is recorded on the report

4.2.2.3.2 The container to be tested shall be conditioned at the test temperature for a minimum of eight

container

4.2.2.3.5 Point of impact shall be at the intersection of L/2 and H/3 (or vary to H/2 from the bottom if

surface variation prevents testing at H/3) as shown in Figure C

Figure C: Impact Point for Plastic Containers

4.2.2.3.6 The “Bruceton” method of conducting the impact testing is recommended This procedure is

listed as “The Up-And-Down Design” (10-4) in the National Bureau of Standards Handbook

91

4.2.2.3.7 Report the impact required to produce the first surface rupture of the container material

Surface failure may be verified by electrical breakdown test, leak test, or other appropriate method

4.2.2.3.8 Impact values may be influenced by the container geometry, i.e on end cells near corners

and on structural or cosmetic features on the container

4.2.3.2.2 Commercial grade polyethylene glycol

4.2.3.2.3 Oven capable of maintaining 93ºC (200ºF)

4.2.3.2.4 Measuring instrument accurate to 0.02 mm (0.001 in.)

4.2.3.3 Procedure

4.2.3.3.1 Place an empty container with flat end walls in an appropriate rigid metal tray Concave or

convex end walls may effect test results

4.2.3.3.2 Fill the container to within 25 mm (1 inch) of the top with commercial grade polyethylene

glycol at a temperature of 93ºC ± 3ºC (200ºF ± 5ºF)

4.2.3.3.3 Place the tray containing the container to be tested in an oven and maintain the polyethylene

glycol at 93ºC ± 3ºC (200ºF ± 5ºF)

4.2.3.3.4 When the liquid in the end cell adjacent to the end wall to be measured reaches a

temperature of 93ºC ± 3ºC (200ºF ± 5ºF), start a one hour soak time

4.2.3.3.5 At the end of the soak period, remove the tray containing the container being tested from the

oven and within five minutes measure the end wall bulge The polyethylene glycol is to remain in the test container until the completion of the measurements

4.2.3.3.6 The bulge shall be determined by comparing the center of the end wall with the plane of the

four corners exposed The center of the end wall is defined as a point half way between the horizontal parting line at the bottom and the bottom of the top band

4.2.3.3.7 Bulge is to be reported as the difference as determined in (4.2.3.3.6)

Bulge values may be influenced by the container geometry, i.e structural or cosmetic features Bulge values may not be representative of a finished battery (a sealed cover would fixture the top of the end wall)

4.2.4 Electrical Breakdown

4.2.4.1 Scope

The purpose of this test is to qualify containers for use in lead acid battery applications 4.2.4.2 Apparatus

4.2.4.2.1 Conductors – close fitting mandrel or suitable liquid equivalent

4.2.4.2.2 Transformer capable of maintaining 30,000 volts

4.2.4.3 Procedure

4.2.4.3.1 Safety precautions should be taken to avoid electrical shock

4.2.4.3.2 The container shall be fitted with a close fitting mandrel and outer shield to within 38 mm (1.5

in.) of the top, or a suitable liquid equivalent

4.2.4.3.3 A minimum potential of 15,000 volts, or 100 volts per mil thickness (as specified on the

container design drawing), whichever is greater, but not to exceed 30,000 volts maximum, shall be applied to the test area of the container for not more than five seconds

4.2.4.3.4 Inspect the container for evidence of being perforated or burned through

4.2.5.3.1 The test must be performed in a clean and dry environment Extreme moisture, even very

high humidity, has a deleterious effect on the test Never try to make a test near an open door, during, or soon after a rain

4.2.5.3.2 Using the broad tip of the marker, lightly apply a single line on all bonding surfaces Interpret

results based on manufacturer’s recommendations

4.2.5.3.3 This test follows closely the procedure outlined in ASTM method D 2578-84 Refer to the

ASTM method when questions arise

4.2.6 Tensile Pull Test for Side Terminals

4.2.6.1 Scope

This procedure provides a method to determine the tensile strength of a side terminal

4.2.6.2 Apparatus

Figure D: Test Fixture 1

4.2.6.2.1 Steel rod One end is to be machined square to fit into the tester grips and the opposite end

is to be threaded to fit into the nut of the terminal Figure D

4.2.6.2.2 Fixture, with hole in center to run the steel rod through, to restrain the face of the terminal

from undue movement during test Figure D

4.2.6.2.3 Tinius Olsen LoCap Tester, or equivalent

4.2.6.2.4 Shim stock of sufficient thickness and diameter to place under the terminal boss not being

tested, to support it over the upper crosshead

4.2.6.3 Procedure

4.2.6.3.1 Age the side terminal sample(s) at an ambient room temperature of 24ºC – 27ºC (75ºF –

80ºF) for a minimum of eight hours before testing

4.2.6.3.2 Adjust load dial to zero Tester speed: 12.5 mm/minute (0.5”/minute)

4.2.6.3.3 Place the fixture to restrain the face of the terminal to be tested over the top of the hole in the

upper crosshead

4.2.6.3.4 Place the terminal or the container to be tested over the restraining fixture

4.2.6.3.5 Apply the tensile load continuously at a jaw separation rate of 12.5 mm/minute (0.5”/minute) 4.2.6.3.6 The failure point will be interpreted as occurring when the tensile value stops increasing

Report this value in kilograms (pounds) of load for the terminal tested

4.2.7 Torque Test for Side Terminals

4.2.7.1 Scope

This test measures the torque resistance between the nut and lead terminal assembly and the container material and the lead assembly

4.2.7.2 Apparatus

4.2.7.2.1 Torque wrench P.A Sturtevant, Div of Dresser Industries Model 1S, 0-35 Joules or or 0-300

inch-pounds capacity or equivalent

4.2.7.2.2 Appropriate holding fixture

4.2.7.2.3 Reference: Figure E: Test Fixture 2

Figure E

4.2.7.2.4 7.9 mm (5/16 in) size socket

4.2.7.3 Procedure

4.2.7.3.1 Age the side terminal container sample(s) to an ambient room temperature of 24ºC – 27ºC

(75ºF – 80ºF) for a minimum of eight hours before testing

4.2.7.3.2 Place and secure the side terminal container in appropriate holding fixture to prevent

movement during test

4.2.7.3.3 Connect the adapter to the terminal in the container and hand tighten the stud until snug 4.2.7.3.4 With the torque wrench in place and set in the zero position and the container firmly secured,

begin applying the torque in a direction perpendicular to the axis of the side terminal and parallel to the side of the container

4.2.7.3.5 Report the maximum torque value, that is the point at which the original (first) loss of torque

occurs, as well as the reason for failure (Example: 28 Joules (250 inch-pound) lead rotating inside the container material and/or nut pulling up inside the lead, etc.)

4.2.8 Leakage Test for Side Terminals

4.2.8.1 Scope

This procedure provides a method for determining if a leak exists at the side terminal of a battery container

4.2.8.2 Apparatus

4.2.8.2.1 Pressure tester capable of maintaining the preset pressure as defined in 4.2.8.3.4 of the test

procedure and testing in accordance with 4.2.8.3.5 of the test procedure

4.2.8.2.2 A cell closure device designed to mate with the upper edges of the container and prevent

escape of air from inside the cell being tested

4.2.8.3.4 Activate the cylinder control to position and seal the outer edges of the cover tongue against

the sponge rubber

NOTE: Cylinder pressure should be preset at 2.5 kg/cm2 (35 psi.)

4.2.8.3.5 The pressure gauge for regulating the air pressure to the container should be preset at 35

kg/cm2 (5 psi.)

4.2.8.3.6 Using eye dropper, slowly add leak test solution to outer surface of insert, making sure the

junction of lead and molded container material is covered Also put solution inside the threaded hole of the insert The solution on the test surfaces shall be free of bubbles

4.2.8.3.7 With the container under pressure, in this position for two (2) minutes, observe the test

solution for signs of leakage indicated by bubbles Report bubbles per minute

4.3.2.2.2 Cold box (capable of maintaining -18ºC (0ºF))

4.3.2.2.3 Measuring device, 0-100 cm or 0-36 in

4.3.2.3 Procedure

4.3.2.3.1 To be free fall tested on a container at –18ºC ± 1ºC (0ºF ± 2ºF) This procedure can be used

at other temperatures providing the temperature used is recorded on the report

4.3.2.3.2 The cover to be tested shall be conditioned at the test temperature for a minimum of eight

hours

4.3.2.3.3 Seat the cover on an appropriate container, or equivalent, in such a manner that the sealing

surfaces of the cover are rigidly supported The test should be done on intermediate and terminal cells

4.3.2.3.4 Standard single wall covers:

(a) Impact on a flat surface as near the center of the cell as possible

(b) The impact point should not be over a partition, rib or reinforced area

4.3.2.3.5 Two piece/double wall covers, sealed manifold vent systems, with and without removable

(c) The impact point should not be over a partition, rib or reinforced area

4.3.2.3.6 The “Bruceton” method of conducting the impact testing is recommended This procedure is

listed as “The Up-And-Down Design” in the National Bureau of Standards Handbook 91

4.3.2.3.7 Report the impact required to produce the first surface rupture of the cover material Surface

failure may be verified by electrical breakdown test, leak test, or other appropriate method 4.3.3 Bushing Impact Resistance

4.3.3.2.2 Cold box capable of maintaining –18ºC (0ºF)

4.3.3.2.3 Measuring device, 0-100 cm or 0-36 in

4.3.3.2.4 Flanged brass pin

4.3.3.3 Procedure

4.3.3.3.1 To be free fall tested on a container at –18ºC ± 1ºC (0ºF ± 2ºF) This procedure can be used

at other temperatures providing the temperature used is recorded on the report

4.3.3.3.2 The cover to be tested shall be conditioned at the test temperature for minimum of eight

hours

4.3.3.3.3 Seat the cover on an appropriate container, or equivalent, in such a manner that the sealing

surfaces of the cover are rigidly supported

4.3.3.3.4 Insert the brass pin into the inside of the lead bushing Seat the flange on the top surface of

the bushing The test should be done on both positive and negative terminals

4.3.3.3.5 The impact missile shall hit in the center of the flanged pin

4.3.3.3.6 The “Bruceton” method of conducting the impact testing is recommended This procedure is

listed as “The Up-And-Down Design” (10-4) in the National Bureau of Standards Handbook

91

4.3.3.3.7 Report the impact required to produce the first surface rupture of the cover material Surface

failure may be verified by electrical breakdown test, leak test, or other appropriate method 4.3.4 Bushing/Stud Torque Test

4.3.4.1 Scope

This procedure provides a method for measuring the torque resistance between the stud and lead terminal assembly, and the cover material and the lead bushing assembly

4.3.4.2 Apparatus

4.3.4.2.1 Torque wrench, P.A Sturtevant, Div of Dresser Industries, Model M300-1S, 3/8 inch square

drive size, 0-35 joules or 0-300 inch-pounds capacity, or equivalent

4.3.4.2.2 One set of positive and negative high profile lead bushing adapters (custom design) or a

ratchet drive stud extractor Snap-On A-36USA8 or equivalent

4.3.4.2.3 Pins sized to fit the inside of the bushings

4.3.4.2.4 Fixture to hold cover in place

4.3.4.2.5 Acorn nut (used for stud testing)

4.3.4.3 Procedure

4.3.4.3.1 Obtain the cover sample to be tested from any point after flame treating

4.3.4.3.2 Age the flame treated cover sample to an ambient room temperature of 24ºC - 27ºC (75ºF -

80ºF) for a minimum of eight hours before testing

4.3.4.3.3 Place pin into the correct high profile lead bushing, making sure that it is seated all the way

down Install bushing adapters or stud extractor Use an acorn nut when testing a stud type terminal

4.3.4.3.4 With the torque wrench in the zero position and the assembly firmly secured, begin applying

the torque in a direction perpendicular to the axis of the high profile lead bushing and parallel

to the top of the assembly

4.3.4.3.5 Report the maximum torque value at the point of failure as well as the reason for failure For

example: bushing rotating inside of plastic as opposed to cohesive lead failure, etc

NOTE: For covers with low profile bushings, using samples obtained after flame treatment (if applicable), form the necessary SAE terminal posts on the cover and then proceed to test as outlined in above procedure

4.3.5 Adhesion

Follow the test procedure used for containers Reference 4.2.5

5 SEPARATOR TEST METHODS

5.1 Test I – Ohmic Resistance

Procedure 1B Ohmic Resistance (Paragraph 5.1.2)

5.1.1.3 Significance and Use:

The measured resistance of a sample varies with the degree of saturation The time required for saturating the sample with acid varies with temperature, acid strength, separator material and pore size distribution Standard practice in the industry is to measure ohmic resistance

after soaking the samples for 20 minutes or 24 hours In addition, separators with average pore diameters of 1 micron or less are boiled before the ohmic resistance measurement The

20 minute soak is used to simulate the resistance of the separator before formation The 24 hour soak is used to simulate the resistance of the separator after formation The boiled “E-R”

is the lowest reading one can obtain and approximates the resistance of the separator after extended service

5.1.1.5.1 Cut sample to appropriate size (if necessary)

5.1.1.5.2 Soak sample(s) for 20 minutes or 24 hours in sulfuric acid

5.1.1.6 Boiling Procedure for Materials With an Average Pore Diameter of One Micron or Less as

Measured by Mercury Intrusion

5.1.1.6.1 Apparatus:

(a) Container that is large enough to hold the ohmic resistance samples

(b) Boiling distilled water

5.1.1.6.2 Procedure:

(a) Cut sample to appropriate size (if necessary)

(b) Boil sample in distilled water for 10 minutes

(c) Remove sample from water and blot the sample dry, removing excess liquid

(d) Soak the sample(s) in sulfuric acid for 20 minutes

5.1.2 Procedure 1B – Ohmic Resistance

5.1.2.3 Significance and Use:

The measured resistance of battery separators is used as a design tool and as a receiving inspection parameter by battery companies It is also used as an internal quality control parameter by the separator industry

5.1.2.4 Definition:

The ohmic resistance of battery separators is defined as the increase in electrolyte resistance caused by the pore structure of the separator

5.1.2.5 Apparatus:

5.1.2.5.1 Digital AC ohmmeter or impedance bridge with sufficient resolution to indicate a 1% change

in the measured resistance

5.1.2.5.2 Resistance measuring cell that uses a fixed area of the sample for the measurement

apparatus A drawing of the cell is included in this procedure

5.1.2.6 Test Specimens

Cut samples such that they are larger than the fixed area window and can be pulled out of the cell by hand

Most automotive battery separators will fit into the Palico cell without cutting

5.1.2.7 Preparation of the Apparatus

5.1.2.7.1 Make certain that the electronics are stabilized If the meter includes a setting that uses a

standard resistance (“Standby” on the Palico), the meter reading should be within 1% of the value of the resistor

5.1.2.7.2 For the Palico 9100-2 system, BCI standard configuration is:

Voltage Electrode Shunt – 1100 Ohms

Current Electrode Shunt – 4700 Ohms

Aperture Size – Circular with total area of 5 square inches

Number of Samples – Measure 1 sample at a time

5.1.2.8 Procedure

5.1.2.8.1 Follow the appropriate pretreatment procedure and put the samples into the storage

compartment of the cell in the following manner:

Support the samples at a 30 degree angle from the horizontal such that only the first half inch

of sample is immersed in the acid

Allow the acid to wick into the sample As wicking continues, immerse the wet area of the separator This method of sample insertion allows air to escape from the pores of the

separator and is especially important in routine 20 minute “E.R.” measurements

5.1.2.8.2 Apply current to the cell Check for D.C polarization on the voltage electrodes If more than

100 mV (0.1V) is present, allow 30 minutes for stabilization and/or discharge of the

polarization If polarization persists, the acid must be changed and the electrodes cleaned 5.1.2.8.3 Check the resistance of the cell Agitate the acid to make certain that the cell resistance is

constant On the Palico cell, move the gate back and forth a few times The cell resistance should be fairly constant at a given temperature, acid concentration, and barrier resistance, varying less than 5%

5.1.2.8.4 If all of the above conditions are met, insert the first separator in the test area and close the

gate Do not close the gate so tightly that the separator cannot be pulled out by hand The sample must be removed by hand in Step 5.1.2.8.6

5.1.2.8.5 Read the cell resistance including the separator If the digital display drifts, wait until it

fluctuates over the same range Use the lowest range that you can to achieve the best resolution, then record the mean value as the reading This is RT in the calculation

5.1.2.8.6 Remove the separator from the test area with one hand Do not move the gate

5.1.2.8.7 When the display fluctuates over the same range record the mean value This is RC in the

calculation

5.1.2.8.8 Repeat this procedure for the number of samples to be tested

5.1.2.8.9 Insert a sheet of solid plastic or glass that has the same dimensions (height and width) as the

separator sample

5.1.2.8.10 Close the gate such that the plastic sheet can be removed with one hand

5.1.2.8.11 Adjust the range of the meter to obtain a reading Record this reading when it is stable (It will

rise for a while after the gate is closed.) This is RB in the calculation

5.1.2.9 Calculations:

5.1.2.9.1 RS = RT – RC

RC is the value obtained in Step 5.1.2.8.7

RT is the value obtained in Step 5.1.2.8.5

RS is the resistance of the measured separator area

5.1.2.9.2 “E-R” = RS x Aperture Area

“E-R” is the resistance of one unit area of the separator

5.1.2.9.3 Correct the “E-R” for barrier resistance and overall thickness:

“E-R” (corrected) = “E-R” x (1 + (.008 x OA x RC/RB))

RB is the value obtained in Step 5.1.2.8.11

OA = overall thickness in mils (thousandths of 1 inch)

5.1.2.9.4 Use either ohms or milliohms for all values Do not mix values

5.1.2.10 Maintenance of Equipment:

5.1.2.10.1 If the ration of RC/RB is less than 015, the barrier resistance correction is unnecessary

Even at an overall thickness of 100 mils, the correction factor is less than 1.5% In the Palico cell, one way to achieve this condition is to seal the voltage electrode partitions to the walls and floor of the cell A cell with sealed partitions is harder to clean but is more stable

electrically and mechanically

5.1.2.10.2 If the barrier resistance (RB) and the cell resistance (RC) are stable, one can establish the

corrections as a set of curves for various separator types and avoid doing this calculation whenever measurements are made However, the barrier resistance and cell resistance should be measured whenever the acid is changed or if the cell is moved They should also

be checked periodically because the cell is usually made of plastic Plastic warps with time and this would cause changes in the resistance readings

5.1.2.10.3 If the bath must be dried for shipment, storage or any other reason, pour the acid out and

re-fill the bath with water Allow it to stand for 24 hours Then drain it and allow it to dry at room temperature

5.1.2.10.4 Correct the readings for temperature by multiplying the “E-R” value by the correction factor

Temperature °F (°C) Correction Factor