Charging at any time will have no effect on the battery. Built-in shock absorbing features protect the battery. Sixteen (16) firm holding contact terminals reduce the risk of power loss/fluctuation in high vibration work environments. Battery's built-in Memory Chip communicates with the charger to maximize battery life using 3 Active Controls (Current, Voltage & Thermal). If you have any issues please contact your local dealer.The item "Makita 18V LXSF01 Cordless Drywall Drill Screwdriver, 2 BL1830 Batteries 18 Volt" is in sale since Monday, June 18, 2012. This item is in the category "Home & Garden\Tools\Power Tools\Combination Sets". The seller is "we_are_tools" and is located in Myerstown, Pennsylvania. This item can be shipped to North, South, or Latin America, all countries in Europe, all countries in continental Asia, Australia.