С haracteristics of Chemical power sources (CPS)

selecting a battery:

Type
Voltage
Charge/Discharge curve
Capacity
Energy density
Temperature dependence
Service life
Self Discharge

the electrochemical series using Eo values:
Eo (cathodic) – Eo (anodic) = Eo (cell)

The open circuit voltage

(OCV), U0
Напряжение разомкнутой цепи
(эксперим.)

ЭДС – электродвижущая сила
(теоретиич.)

will vary as it is charged and discharged (see Figure

1).
The MPV (mid-point voltage) is the nominal voltage of the cell during charge or discharge. The maximum and minimum voltage excursion from the nominal value is an important design consideration: a "flatter“ discharge curve means less voltage variation that the design must tolerate.
When peak charged, the actual cell voltage will be higher than the MPV. When nearing the EODV (end of discharge voltage) point, the cell voltage will be less than the MPV. The EODV is sometimes referred to as the EOL (end of life) voltage by manufacturers.

of electricity involved in the electro-chemical reaction. It is denoted

Q and is given by:



where x = number of moles of reaction, n = number of electrons transferred per mole of reaction and F = Faraday's constant.
The capacity is usually given in terms of mass, not the number of moles:




where Mr = Molecular Mass. This gives the capacity in units of Ampere-hours per gram (Ah/g).

Емкость элемента – это количество электричества, которое
химический источник тока отдает при разряде

C = I .  (А . ч, если элемент разряжается током I (A) в течение  (ч))

of a battery is generally expressed in two ways (see

Figure 2).
The gravimetric energy density of a battery is a measure of how much energy a battery contains in comparison to its weight, and is typically expressed in Watt-hours/kilogram (W-hr/kg).
The volumetric energy density of a battery is a measure of how much energy a battery contains in comparison to its volume, and is typically expressed in Watt-hours/liter (W-hr/l).

discharge will also be higher at lower temperatures, as will

the capacity- this is illustrated by the following graph:

by:
Over-charging
Over-discharging
Short circuiting
Drawing more current than it was designed to produce
extreme

temperatures
physical shock or vibrations

Metallic dendrites
(battery death due to aging)

"shelf life" of a battery.

In general, Li-Ion is the best

of the lot, while Ni-Cd and Ni-MH are fairly comparable to each other. Ni-Cd is typically a little better than Ni-MH, but this may even out as Ni-MH manufacturing technology matures.