I hate to give this kind of advice cause I don't know how hard you might have it :( But I don't think you want to train your child that it's ok to chew batteri

I hate to give this kind of advice cause I don't know how hard you might have it :( But I don't think you want to train your child that it's ok to chew batteries, the moment you don't look he'll turn to the real stuff with no distinction. Ours is leaking and chewing everything he finds, including bus railings and the likes. A year ago we started giving him those necklaces with rubber pieces that we tell him are ok to chew. That didn't fix the issue entirely, but noticeably improved things, and now he's asking for these every morning.