Alpha Technologies Lomain Ni-Cd Pocket Plate Battery - Manual (Page 16)

745-680-B10-001 Rev. A 16
2.0 Battery range and applications
3.0 Electrochemistry of Ni-Cd batteries
Oxidation of cadmium at the negative electrode
Reduction of trivalent nickel ions to bivalent at the positive electrode
During charging the both reactions are reversed.
The complete reaction is: indicated below:
Negative electrode:
Positive electrode
Cell reaction
LOMAIN KGL...P
The Alpha Lomain cell type is used for low rates of discharge over
long periods where the current is relatively low in comparison with
the total stored energy. The discharges can generally be infrequent
and the recommend discharge time for the KGL...P range is 1 hour
to 100 hours.
LOMAIN KGM...P
The KGM...P type battery is designed for “mixed loads” that include a
mixture of high and low rates of discharge. It is used for frequent and
infrequent discharges and the recommended discharge time is 30 to
120 minutes.
Cd Cd 2+ + 2e –
Ni 3+ + e – Ni 2+
Cd + 2 OH – Cd(OH)
2
+ 2e –
2NiOOH + 2 H
2
O + 2e – Cd(OH)
2
+ 2e –
2NiOOH + Cd + 2 H
2
O 2Ni(OH)
2
+ Cd(OH)
2