New Li-ion batteries

http://news.bbc.co.uk/1/hi/sci/tech/7938001.stmhttp://news.bbc.co.uk/1/hi/sci/tech/7938001.stm

New batteries that dont get hot, explode and can be charged and discharged in seconds......

Ideal for me really :)

Sounds like a great chance for us to loose even more wieght ...... :):):):):)

See here for a more balanced article on the development. Already licenced by A123.
http://www.technologyreview.com/energy/22280/http://www.technologyreview.com/energy/22280/

Note that it only says that it ..may also recharge quickly, but then faster charging is not particularly useful - A123s can already be charged in 10 mins. You would need vast power supplies to charge in seconds. Unless you used another set of them charge the ones in the robot...

Higher discharge currents than current A123s would only really be useful for very high power (10 kwatt in a heavy) intermittent use electric weapons. More continuous use and youre limited by capacity.

If you stuck to the 36V limit, it probably wouldnt be a conventional motor producing those sort of power levels, because you would be talking thousands of amps.

But if we could get an EO to agree to use several hundred volts... then theres this nice little 60 kwatt brushless motor:
http://www.racecar-engineering.com/news/products/281799/exclusive-magneti-marelli-reveal-f1-kers.htmlhttp://www.racecar-engineering.com/n...magneti-marell i-reveal-f1-kers.html

John

Well there we go, lets up the voltage! :mrgreen:

It is at least somewhat likely that the test cells are so small, or have such low specific capacity that they do not properly represent the effects of heat generation during charging. If these test cells are practically only voltage limited because they can dissipate heat rapidly, you can calculate the resistance of a real cell like the A123 M1 dropping to not less than ~1.5 milliohms with the new material and few other necessary modifications. This would allow charging in a minute which they do mention in their practical examples, but would rule out repeatable charging in less than 20 seconds.

It would be difficult to leverage very efficient cells such as these at their peak power in pulse applications unless great care is taken in the designs to prevent hot-spots appearing. In any case, improvement in the ion mobility reduces the duration maximum power can be tolerated even though it increases the duration you can hold at any particular value of power.

Still a big improvement, even useful in the case of being limited to a nominal 36 volts, simply because sag is generally significant.