Lithium Battery Discovery

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bitternboy
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Lithium Battery Discovery

Post by bitternboy »

I was just reading Focus mag, and apparently scientist have recently discovered why Lithiums overheat and catch fire. According to research from Cambridge, rapid and over charging can cause metal fibres called "lithium dendrites" to grow inside the battery and cause short circuits. Avoiding this problem will almost certainly lead to more reliable batteries for laptops, gadgets and maybe even robots!
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BeligerAnt
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Post by BeligerAnt »

True, overcharging is a sure-fire way to ignite your lithium batteries. This is why all the videos on YouTube of R/C planes giong up in flames are on the ground. The batteries are being charged in the plane, the charger develops a fault or is not a good design, the battery gets overcharged and it's goodbye expensive plane :(

Follow the manufacturer's advice and charge your batteries on a non-flammable surface and keep an eye on them. A LiPo sack is a worthwhile investment for safely charging batteries.

The other way to really damage a lithium battery is to overdischarge it, to below 2.5V (sometimes 3V) per cell. Many speed controllers these days have an under-voltage lockout so they shut down when the voltage gets to 5V or 6V (for a 2-cell battery). If you don't have this feature in your speed controller, be very careful with your batteries and/or consider fitting a low-voltage indicator. (Available from Model Power).

There was also a report last week about the use of carbon nanotubes in lithium batteries to increase the power output significantly (because a carbon nonotube has such a huge surface area compared to normal carbon granules).
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razerdave
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Post by razerdave »

Unfortunately I've lost 2 lipos to over-discharge, left Stewie switched on once and drained it, and one in a K*bots unit.
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