Patent ID: 8890486

Claim:
An apparatus for charging a battery, comprising: a constant current circuit, a constant voltage circuit and a control circuit; wherein the control circuit is adapted to control the constant current circuit to perform constant current charging to the battery; after a battery voltage during the constant current charging reaches a preset charging limited voltage, control the constant voltage circuit to perform constant voltage charging to the battery; and if a charging current during the constant voltage charging becomes smaller than or equal to a predetermined threshold, start to charge the battery by pulse charging until an open circuit voltage of the battery is larger than or equal to a preset voltage threshold; a clock circuit; wherein the control circuit further comprises: a first unit, adapted to stop the charging to the battery and trigger the clock circuit to start timing; and a second unit, adapted to, when a timing period reaches a preset off time, clear the timing of the clock circuit and determine whether an open circuit voltage of the battery is larger than or equal to the preset voltage; if the open circuit voltage is larger than or equal to the preset voltage, terminate the charging; otherwise, control the constant voltage circuit to perform the constant voltage charging to the battery and meanwhile trigger the clock circuit to start timing, and when a charging time reaches a predetermined pulse-charging-on time, clear the timing of the clock circuit, and trigger the first unit to stop charging the battery and to trigger the clock circuit to start timing; wherein a voltage used when the constant voltage circuit performs the constant voltage charging to the battery is the charging limited voltage.