| 摘要 |
In a method and an apparatus for charging batteries using a source 3,4 which delivers a charging current which decreases with an increasing battery voltage, the charging current is continuously integrated 14, to determine the total number of ampere hours supplied, the rate of change of the charging voltage is determined 15 and the maximum value of the rate of change established the time (T2, Fig. 1) at which the rate of change of the charging voltage again falls to a predetermined percentage, for example about 40-50%, of its previously established maximum value is then established and charging of the battery is continued from this time (T2) until the battery has been supplied with a further number of ampere hours constituting a predetermined percentage, for example about 10- 15%, of the total number of ampere hours supplied to the battery up to the aforesaid time (T2). Charging of the battery is then discontinued. The battery may subsequently be trickle charged, e.g. by connecting it to the charging current source for a predetermined short period as soon as the battery voltage has fallen to a predetermined level. Calculation of the rate of change of charging voltage may commence only when the charging or battery voltage has reached a predetermined value; the battery may be charged-with a higher current until that time. Means 6,9 may be provided to compensate for mains voltage variations when determining the rate of change of charging voltage. Calculations and control may be effected by a microprocessor 12, and a display 20 may indicate main charging time, additional charging time, total charging time, ampere hour, charging voltage, and charging current. <IMAGE> |
