摘要 |
The characteristic voltage-versus-time curve for a nickel-cadmium battery on a fast charge, e.g., being charged at the C/1 rate, increases to a peak voltage and thereafter decreases. To ensure that the battery is fully charged, the fast charge is discontinued on the decreasing portion of the voltage-versus-time curve. The fast charge may be stopped when a predetermined negative rate of change of the voltage is obtained. Or the fast charge may be cut off when the battery voltage decreases a predetermined amount below the peak, that is, when the difference between the maximum measured battery voltage and the present battery voltage exceeds a setpoint. After the fast charge is discontinued, a trickle charge, e.g., a C/10 charge or less, may be instituted or the charging current may be interrupted altogether, i.e., the battery charging circuit may be opened.
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