Honestly just read that a standard cordless drill battery has about the same energy as a hand grenade. Found it in a tool safety article. Anyone know if that's actually true?

4 comments

4 Comments

A typical 18V 5Ah drill battery stores around 90 watt-hours of energy. That's a lot of potential chemical energy packed in a small case, similar to an explosive device. The big difference is the rate of release, with a grenade discharging it all in an instant.

the_max2mo ago

Totally get what you're saying. I once saw a video where a guy purposely shorted a big LiPo battery pack and it basically turned into a firework, shooting flames everywhere in seconds. It wasn't a shockwave like a bomb, but all that energy coming out at once was still pretty wild and dangerous.

waderamirez5d agoMost Upvoted

Hang on, I gotta push back a little here. Seen a few of those videos myself and yeah, it's scary, but a lot of times those are deliberately abused or damaged cells, not a normal failure. In my experience, most battery fires in power tools or vapes happen because of physical damage or cheap knockoffs, not just regular use. @sean48 made a good point about the chemical release being slower, I think that's the real key. Are we really comparing a controlled thermal runaway to a military-grade explosive? I mean, you're more likely to get burned by a hot soldering iron than a battery grenade in your garage. Your mileage may vary, but I'm not losing sleep over my Makita batteries.

sean482mo ago

Disagree on the explosive comparison. A lithium battery's energy is stored chemically and released slowly through controlled reactions, while explosives undergo rapid chemical decomposition. The energy density might look similar on paper, but the release mechanisms are fundamentally different physics. A grenade creates a shockwave, a battery just heats up if it fails.