 If you're looking to maximize the lifespan of your rechargeable lithium battery, keep it as close as possible to room temperature and don't store it in the fridge or freezer. When you do store them, try to keep them about 50% charged to maintain functionality. Over time, leaving them in a fully depleted state can cause them to permanently lose capacity or just die altogether. And as always, avoid anything sharp that could puncture the lipo's casing and cause the internal chemicals to mix and leak, and the battery to become puffy and possibly catch fire or explode. Yeah, a puffy lipo sounds kind of cute, but it's not a happy thing.