Very dangerous for explosions. However there is a guy developing a lithium battery with different materials with the lithium that you can cut into pieces and it doesn't catch on fire or explode or stop working in tiny pieces. It looks like a insulated postage envelope. It was on nova. I believe he's using vinyl instead of metal. Let me see if I can find it and attach it here for you.
RE: Elon Musk to build Giant Lithium Batteries.