Technical Glossary for Batteries, Power Supplies & More
Absorption: hydrogen retention by the hydrogen-absorbing Misch metal alloys of batteries’ negative electrodes
Acid battery - The battery in which acid is used as electrolyte, e
Technical Glossary for Batteries, Power Supplies & More
Absorption: hydrogen retention by the hydrogen-absorbing Misch metal alloys of batteries’ negative electrodes
Acid battery - The battery in which acid is used as electrolyte, e.g., lead-acid battery in which sulfuric acid is the electrolyte.
Active Material: electrode material which produces electrical energy during discharge from chemical energy stored during charge
Alkaline storage battery - A battery which employs alkaline aqueous solution for its electrolyte. The Nickel-cadmium battery as designed.
Ambient temperature - The average temperature of the battery's surrounding medium, typically air.
Ampere Hours (Ah): unit expressing the capacity of a battery or cell. Ampere Hours are the product of a battery's or cell's discharge rate and discharge time. Usually measure in mAh (milli-Amps x hours)
Anode: electrode where oxidation takes place during electrochemical reaction. Negative electrode is the anode during discharge; positive electrode is the anode during charge
Assembled battery - Any battery composed of multiple cells.
Battery (Battery Pack): two or more electrically connected cells in a series/parallel arrangement, designed to create the desired voltage/capacity. "Battery" is the common term for a single cell
Button Cell: a battery cell with overall height less than its diameter. Button cells are manufactured with circular disc electrodes that are separated with a separator sheet
C - C designates the nominal capacity of the battery. The charge-discharge current is specified in terms of a multiple of C. For example, the 0.1 current for N-1300SC is equal to 1300 X 0.1 = 130mA.
C-rate - Unit by which charge and discharge times are scaled. The capacity of NiCd batteries is commonly rated at 1C, meaning that a 10000mAh battery would be discharged at 10000mA for one hour.
Cadmium - Chemical symbol: Cd. This metallic element is the chemically-active material of the Nickel-cadmium battery's negative electrode. When the battery is charged, the negative electrode surface consists of cadmium. As the battery discharges, the cadmium progressively changes into cadmium hydroxide (CdOH2).
Cadmium hydroxide - Active material used at the negative electrode of the Nickel-cadmium cell.
Cadmium salt - A chemical compound in which the hydrogen atom as been replaced by the cadmium atom: e.g.) 2HNO3 + Cd(OH)2 -> Cd(NO3)2 + 2H2O cadmium nitrate.
Capacity - The electric energy content of a battery expressed in ampere hours. The energy is referenced to the discharge at a constant current for a measured period of time until a specified cut-off voltage is reached.
Cathode: electrode where reduction takes place during electrochemical reaction. Positive electrode is the cathode during discharge; negative electrode is the cathode during charge
Capacity: maximum amount of electrical current that can be withdrawn from a battery cell under specified conditions. Capacity is the product of discharge rate and discharge time (mAhr = mA x hrs); measured in milli-amp hours (mAh)
Capacity offset - A correction factor applied to the rating of a battery if discharged under different C-rates from the one rated.
Cell: a cell is the basic electrochemical unit which stores electrical energy or releases stored electrical energy
Cell-mismatch - Cells within a battery pack that contain different capacity and voltage levels.
Cell Reversal: the discharging of a cell to a state of reversed polarity. Usually requires three or more cells for this to occur
Change in Temperature (ΔT): charge termination based on difference between ambient temperature and cell temperature
Change in Temperature/Change in Time (dT/dt): charge termination based on change in temperature over time. This termination is meant to detect rapid temperature increases created just before a battery or cell reaches its full charge. Normal dT/dt is 1°C/minute
Charge - The process of replenishing or replacing the electrical charge in a rechargeable cell or battery.
Charge Acceptance: a cell's ability to store energy. Can be affected by temperature, charge rate, and state of charge
Charge Efficiency: ratio of a cell's output during discharge to its input during charge. Ratio can be expressed in efficiency of capacity, nominal voltage, or power
Charge Rate: current applied to a cell to restore its capacity. Charge rate is usually expressed in terms of the cell's C Rate
Charge retention - Residual capacity after a period of storage of a fully charged battery.
Charge, state of - The capacity remaining in a cell or battery.
Chemical cells - The type of cells which convert energy obtained by chemical reactions into electrical current. Most of the popularly used cells belong to this group.
Constant voltage charge - A charge during which the voltage across the battery terminals is maintained at a constant value. This method is not normally used for sealed nickel-cadmium cells or batteries.
Constant current charge - A charge during which the current is maintained at a constant value. Sealed nickel-cadmium batteries are normally charged at a constant.
Coulomb - A unit to measure the in-going charge and out-going discharge current of a battery. A coulomb is equal to the electricity transferred by a current of one ampere in one second. (The maximum energy a molecular weight of a chemical system can deliver is one Faraday of energy or