- Published in issue 5/1995 on page 38
NiCd battery-quality tester
The capacity of a fully charged NiCd (nickel-cadmium) battery can be measured fairly accurately by draining the battery with a fixed current until a certain cell voltage is reached. The product of current and time then yields the actual capacity. In the design presented here, the discharging and voltage measurement operations run under the control of a microprocessor. Up to eight cells may be tested in one go.