Something to know about Ni-Cd battery

What is a Ni-Cd battery?

A nickel-cadmium battery (Ni-Cd or Ni-Cad) is a rechargeable battery used in portable computers, rigs, video cameras, and other small battery-powered devices that require uniform discharge. Ni-Cds use electrodes made from nickel oxide hydroxide, cadmium metal, and potassium hydroxide alkaline electrolyte.

Ni-Cd Battery Pack

Two or more Ni-Cd battery cells combined to form a battery pack. Because they are typically similar in size to primary cells (non-rechargeable batteries), Ni-Cds may have lower terminal voltages and smaller ampere-hour capacities. However, unlike primary cells, Ni-Cds provide a nearly constant terminal voltage during discharge, which can result in an almost undetectably low charge. During discharge, Ni-Cds convert chemical energy into electrical energy. During charging, Ni-Cds convert electrical energy back into chemical energy.

Advantages of Ni-Cd batteries

✳Withstand long periods of deep discharge

✳More charge/discharge cycles than other rechargeable batteries to extend battery life

✳Higher energy density, lighter and more compact than lead-acid batteries Ni-Cd is preferred when size and weight are critical factors, such as in aircraft

✳Lower self-discharge rate than nickel-metal hydride (Ni-MH) batteries (20% per month vs. 30% per month)

Some notes about using Ni-Cd batteries

Ni-Cd batteries are highly toxic. In addition, nickel and cadmium are expensive metals.

Unlike lead-acid batteries, Ni-Cd batteries can overheat, go into thermal runaway mode and self-destruct when charged with a generator - even in an overcurrent cutoff system. However, Ni-Cd battery packs are usually equipped with an internal thermal charger cut-off device that signals if the battery heats up and/or reaches its maximum voltage.