TAILIEUCHUNG - B BATTERIES
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 | B BATTERIES 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 . 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 . of metal carbon graphite metal oxide such as PbO2 MnO2 or semiconducting 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. Positive charge carriers are referred to as cations negative charge carriers as anions. The intrinsic conductivity of pure water is too low to be an appropriate electrolyte. k pS cm 1 at 25 C owing to autoprolysis 2H2O H3O 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 381 382 Batteries I Nomenclature Table 1 Definitions of anode and cathode Cathode Anode Sign Function Sign Function .
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