LiPo Packs, Fires and Facts

So, if you’ve looked into lipo chemistry at all, you have no doubt read all the warnings about their volatility and the potential for fires and explosions.  Repeatedly I’ve been told they’re acceptable for experimental use, but not safe for daily commuters.

I call bull.

First, I know a few guys who are using them, daily, and have been for a good long while.  Second, I did this video, trying to do my own lipo fire with some failed cells, and, you can see for yourself, the result was a little disappointing.

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I have, since then, got a lot of advice on how to get a better result, that is, a better fire and explosion, which basically comes down to this.  First, work with a cell with a maximum charge, even hugely overcharged.  Pierce the cell with a conductive material, like a nail, that will short the cells and not burn up.  Heat the cells, best, by discharging them.  Then they may burst into flames and even explode, but maybe not.

So, if you have fully charged or overcharged cells, and you’re running your bike really hard, and you lay it down and something conductive pierces casing an then the cells, then you may be in trouble.

Reminds me of…  gasoline?

In fact, from a post on ElMoto.net, LiveForPhysics, AKA builder of the Death Bike and Guy Who’s Blown Up More Lipo Than Anyone I Know said “The modern RC LiPo packs are fairly shockingly stable. I’ve had some that required overcharging past 8v, taking in 3x the cells rated capacity before getting fire balls (though most blow around 5.5v). It can be difficult to get fireballs on a healthy cell from any amount of physical trauma (including stabbing with conductive materials) anymore with modern RC LiPo.

To be sure, lipo is touchier than most any other chemistry, and by that I mean you can junk the pack a lot easier than others.  Overcharge it, over-drain it, there’s a host of care and feeding instructions I’ve posted.  Treat them badly, they will repay you by failing.  But burst into flames for no apparent reason?  I’m beginning to think this is, at best, old news, and bad information.  At worst, it’s internet hype and hysteria fed by maybe nothing more than people’s love of a good explosion video.  Actually, there is a worse scenario, that people are actively trying to harpoon lipo chemistry for their own nefarious reasons…  or maybe it’s Space Aliens from the Future trying to corner the HobbyKing lipo market…  who knows?

Here are a few links to some “Care and Feeding of lipo” that I found helpful.

One thing is for sure…  lipo chemistry and radio-control lipo packs have gone through some very rapid development in the last few years.  I suspect a lot of the “exploding lipo” comes from early packs and “sketchy suppliers.”

So, my next step is to order and build a bigger pack, something around 30ah, so I can get a little more mileage out of it, and a little more current at full-throttle…  and I’m going to stick with the Turnigy hardcase lipo.  Stay tuned…

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