I don't view the SMPL mod as safe if it has any battery at all in it, although they can be perfectly safe Christmas tree ornaments if you remove the battery and stick a bent paper clip through the 510 hole. That said, Fat Daddy Vapes and RTDVapor both sell replacement wraps for 18650s, I happen to know. I wouldn't use a torn wrap battery even in a safe mod. That's a good way to get an autofire.