CCxRC 9"x12"Large LIPO Bag
I use LIPO bags to hold my batteries while they charge. While they claim to be fireproof, I think of them as a fire retardant that will give you extra time to jump into action if there is a problem and the reduce the damage. You still need to be around while your batteries charge and attentive to what is going on in the process. Your preparedness helps make them more effective.

I also carry my batteries in these bags when I go to comps or travel on planes to protect the batteries from easily being cut or punctured. It will also help to slow and minimize the flames should a problem occur.
 
 
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