Constant current - constant voltage (CC-CV) charging mode , the CC-CV chargingmode , the first battery charging current , the charging current starts todecrease ; before the battery voltage has not yet reached saturation ; batteryvoltage reaches saturation and remains constant, the charging current is furtherreduced. this charging method , can be avoided in the vicinity of the saturationvalue of the battery voltage is still a large current charging of the battery ,resulting in overheating .