My biggest takeaway from the site was the bit on batteries. In particular, the repeated reminder that we should never leave charging batteries unattended. I won

My biggest takeaway from the site was the bit on batteries. In particular, the repeated reminder that we should never leave charging batteries unattended. I wonder how important this is to follow really... We have 100s of millions of devices out there charging everyday (cellphones, laptops, etc...) and we don't really worry too much about these batteries catching fire.