First, if the battery car is fully charged and the charging device is not removed, it will not automatically power off, the charging device will continue to charge the battery, but the charging device has a protection device, which automatically breaks the main charging device after full, and enters the floating charging state. Second, the so-called floating charge is to switch to a small current to continue charging the battery after the battery is full, which is called floating charging, also known as trickle charging. The small current is generally not artificially set, but after the voltage is set to the floating charge voltage (such as the 12V battery, the floating charge voltage is in the range of 13.2V ~ 13.8V), the battery is fully charged and can accept the current is very small, and the floating charge flow is automatically formed. The purpose of floating charge is three: 1, keep the battery voltage in the range of floating charge voltage, at this time the battery grid (that is, the conductive skeleton of the plate) corrosion in the slowest state, can extend the battery life. 2, supplement the capacity loss caused by battery self-discharge, keep sufficient power. 3, inhibit sulfation caused by recrystallization of active substances.
Battery car charger lines are generally semi-intelligent charging lines, that is, fast charge first, and then constant current charging, when the battery voltage reaches a certain standard, the intelligent detection circuit in the charger will automatically cut off the charging state, the phenomenon you said can have two reasons, one is that the battery aging feedback to the charger detection circuit voltage does not reach the limit value of the need to cut off the charging process, Second, the charger charging detection line fault can not cut off the charging state. It is recommended that you find a charger of the same model to try to determine whether the battery is faulty or the charger is faulty, and then make a choice.