NiCad

The nickel-cadmium battery (commonly abbreviated NiCd and pronounced "nye-cad") is a popular type of rechargeable battery using nickel(IV) oxide and metallic cadmium as electrodes. The principal advantages of NiCd over other rechargeable types is lower weight for a given quantity of stored energy, good charging efficiency, small variation in terminal voltage during discharge, low internal resistance, and non-critical charging conditions. They can be used in place of regular batteries in most applications.
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Noun
1. a rechargeable battery with a nickel cathode and a cadmium anode; often used in emergency systems because of its low discharge rate when not in use
(synonym) nickel-cadmium accumulator
(hypernym) storage battery, accumulator

NICKEL-CADMIUM. NICAD