| 摘要 |
The quasi-constant charging current provided by a constant voltage source 3 and a series resistor 4 is terminated in response to a temperature detector 7a within the battery 2. The temperature detector may be an NTC thermistor 7a which controls a transistor switching circuit 8a, 8b in the charger. Alternatively, the temperature detector may be a bimetal switch (7c, Fig. 5) carrying the charging current so that only a two-terminal connector is required between the charger and battery. The charging current may also be turned off in response to a high temperature in the charger as sensed by a further thermistor 7b or by a further bimetal switch (7d, Fig. 5). The system may be used for both nickel cadmium and nickel hydride batteries, eg. for charging the battery of a portable telephone from the cigarette lighter socket of an automobile. <IMAGE> |
