Alpha Technologies Lomain Ni-Cd Pocket Plate Battery - Manual (Page 19)

19 745-680-B10-001 Rev. A
4.0 Operating Features, continued
4.5 Impact of temperature on lifetime
Operating battery systems at higher temperatures reduces the service life. The Alpha Lomain
Ni-Cd battery is designed to be less susceptible to the affects of higher temperatures than
lead-acid batteries as shown by the following graph.
For standard Ni-Cd batteries the normal operating temperature is based at + 20 °C (± 5 °C)
and, therefore, special considerations have to be taken into account when specifying a Ni-Cd
battery for high temperature applications.
4.6 Short-circuit values
The short-circuit values of a Alpha Lomain Ni-Cd pocket plate battery are unique to each cell
range. Contact your dealer for specific information.
4.7 Open circuit loss
The state of charge of a cell on open circuit slowly decreases due to its self-discharge.
This decrease is quite rapid during the first two weeks and then stabilizes at about 2% per
month at +20°C.
In general the self-discharge of a Ni-Cd battery is affected by various temperatures. The open
circuit loss is reduced at low temperatures; that is, the self-discharge is significantly increased
at higher temperatures.
Fig. 12, Battery life at higher temperatures as percentage of +25°C lifetime