BATTERIES Contents Nomenclature Capacity Energy Self-Discharge Charging Methods Fast Charging Charge–Discharge Curves Partial-State-of-Charge Adaptive State-of-Charge Determination Dynam
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Contents
Nomenclature
Capacity
Energy
Self-Discharge
Charging Methods
Fast Charging
Charge–Discharge Curves
Partial-State-of-Charge
Adaptive State-of-Charge Determination
Dynamics
Alternating Currents
Parallel and Series Connections
Modeling
Lifetime Prediction
Codes and Standards
Nomenclature
P Kurzweil,University of Applied Sciences, Amberg, Germany
& 2009 Elsevier B.V All rights reserved.
Sign Conventions and Potential
Definitions
Every electrochemical cell – primary cell, secondary cell,
fuel cell, electrochemical capacitor, electrolysis cell, or
corrosion element – consists basically of two electrodes,
also called the two half-cells, dipping into an electrolyte
At the electrodes, electrochemical reactions take place
that involve electrons as reactants
Definitions of Conductors, Reactants, and Cell
Polarity
Electrode: An electronic conductor e.g of metal, carbon,
graphite, metal oxide (such as PbO2, MnO2), or
semi-conducting materials The polarity of the electrode refers
to the charges residing at its surface and its terminal to which the external electric circuit is connected
Electrolyte: An ionic conductor, liquid, solid, or fused, which transports the electric current by the mobility of ions, for example, water-based or organic salt solutions, diluted acids or bases, salt melts, oxide ion conducting ceramics (such as ZrO2), or conducting polymers Posi-tive charge carriers are referred to as cations; negaPosi-tive charge carriers as anions The intrinsic conductivity
of pure water is too low to be an appropriate electrolyte:
k¼ 0.0635 mS cm1 at 25 1C owing to autoprolysis (2H2O"H3Oþþ OH) At the electrode–electrolyte interface change occurs from conduction by electrons to conduction by ions
Anode: The electrode at which electrochemical oxidation takes place, a chemical reaction that results in the release of electrons by the active material, so that the oxidation
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