Leaving a battery in the charger will not. overcharge or damage it. You can remove a battery/radio from the charger at any time. without harming the battery, the radio, or the charger. When you return the battery/radio to the charger, charging. is automatically resumed.es u an leave the charging on if the battery is not dry battery and the charger isnt available all the time but i recommend u buy a 12 v over charge protection kit or u can make it urself.