Our lithium-ion batteries use advanced technology, and therefore are not impacted by historical issues known to sometimes be an issue with older 3rd party li-ion technology. Older technology would have required the user to completely discharge all stored (“memorized”) energy prior to recharging the battery. In other words, due our battery manufactured performance, you can actually charge a Warrior battery whenever you want, even if it is not fully exhausted. You can trust the Warrior!