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What's Wrong With Lithium Ion Batteries?
An anonymous Coward writes "Lithium ion batteries short-circuit. They overheat. They burst into flames. The reasons behind the recent spate of problems with a technology invented by Sony more than a decade ago are complex and varied, making for one big engineering headache."
"Couple this with reactive/flamable substance that make up batteries, and you have a lightshow. ... Some designs minimize the risk, none remove it."
t e_battery/
This is (lately) misinformation. It's basically true of any conventional LiIon battery type. But unlike the LiIon chemistry in common use today in laptop batteries, the newer lithium phosphate (LiFePO4) LiIon chemistry is inherently non-flammable and non-explosive. It's also considerably less energy dense than standard LiIon chemistries and more expensive to manufacture, thus big business' near-total lack of interest in rushing to develop it for consumer devices over the past several years. But it is now used in a few high current drain applications where conventional LiIon would be a poor choice, e.g. in some DeWalt power tools. When the cost comes down enough, you'll see lots more of these batteries, notably in electric vehicles, where they effectively eliminate laptop-type LiIon's barely-restrained violent urge to turn vehicles into smoldering heaps of rubble.
See http://en.wikipedia.org/wiki/Lithium_iron_phospha
The batteries that are causing troubles now are all Lithium polymer batteries. The electrolyte-fluid in them has been replaced with a polymer that amongst other things made it possible to replace the heavy metal cylinder with aluminium/plastic packaging and make the battery in all kinds of forms.
Unfortunately, at the same time the chemistry of the cells was changed such that if a thermal runaway ever happened, the venting gasses would ignite with oxygen and would ignite the cells next to it too. That is exactly what is happening.
I am rather supprised that no one yet has mentioned A123 systems. They make/market a new type of lithium-(nano)phosphate cell, that has none of the drawbacks of lithium-polymer batteries. They will not catch fire in a thermal runaway or when pierced, can be much more abused than LiPos and have a much longer lifespan to boot (2000 cycles instead of 500). It's no wonder that these batteries will be in the next generation of hybrid cars, as they weigh half as much as the NiMH batteries used now (LiPo would be too dangerous in a collision) and can generate much more current too. (~10C for NiMH, ~40C for A123).
So there is hope one the battery technology front, it's just that the current best option is a bit dangerous.
This space is intentionally staring blankly at you
The joke - Lithium has been a standard treatment for bipolar disorders since the late 50's. It can work remarkably well. Funny thing is that it was discovered by giving it to rats. The rats calmed down though because it made them sick, and this was misinterpreted. But it works well in humans by coincidence.