What do you use to protect the "HOT END" of your spare Mine-lab batteries?? I've got one 1600 Mah battery pack and one 1800Mah battery pack with the hot ends wrapped in electrical tape just waiting for the opportunity to short out while in transit/storage (ruining at least one day.and providing hysteric entertainment for observers as I futily try to rescue everything else)...I just thought some of you Mine-lab veterans would know of a plastic cover that would fit over the end. Thanks!!!