stevedas

Li house batteries typically have a Battery Management System (BMS) internal to the battery package that shuts the battery off before the actual Li battery goes COMPLETELY dead. If you recharge the battery at that point, there will be no measurable degradation to the battery BUT, if you let it sit long enough for the LI batter "behind" the BMS to go completely dead, you have probably lost the battery. It's important to NEVER let one sit l;like that without recharging VERY soon so this doesn't happen. OCCASIONALLY the battery can be saved if you can get to the individual cells and charge this separately but in most cases, it's "buy a new battery time". Stevfe