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[XOXOXO]

Version 2 of the OLPC is coming out fairly soon I've heard. I know there's a LOT of discussion about features for it, but this one takes the cake in my opinion: http://www.photosnews.com/articles/2656/1/

It is a new battery by Toshiba. It's cycle life is astronomical, its safe, its charge rate is beyond anything currently available:

1. Excellent safety
     SCiB adopts a new negative-electrode material that offers a high level of thermal stability and a high flash point electrolyte, and has a structure resistant to internal short circuiting and thermal runaway. The possibility of rupture or combustion is very low.
 
2. Long-life cycle
     Capacity loss after 3,000 cycles of rapid charge and discharge is less than 10%. SCiB has an excellent long lifecycle, and is able to repeat the charge-discharge cycle over 5,000 times. This means that the SCiB can be continuously used for more than 10 years with a once-a-day recharge-discharge cycle.
 
3. Rapidly rechargeable
     The superb safety characteristics of SCiB allow recharge with a current as large as 50 amperes (A), allowing the SCiB Cell and SCiB Standard Module to recharge to 90% of full capacity in only five minutes.
 
4. High power (practical capacity)
     The SCiB has an input-output performance equivalent to that of an electric double layer capacitor. This feature is suited to high power applications.
     
5. Temperature
     

SCiB operates well in temperature extremes, with sufficient discharge at temperatures as low as -30°C. This characteristic also assures wide application in cold climates.

It is set for commercial release in March, 2008. However, I am sure if OLPC contacted them for backroom discussion, there could be something worked out. The other issue may be price. Nonetheless, this battery is one I would recommend OLPC check out.

[XOXOXO]

Here's a whole bunch more info on the specs of it:
http://techon.nikkeibp.co.jp/english/NEWS_EN/20071212/144076/

The energy density of the 150g-cells about 67.2Wh/kg
according to Wikipedia, NiMH batteries have a density of about 70Wh/kg.

Both the SCiB battery and NiMH are essentially the same when it comes to capacity.

Imagine the extraordinarily great Real world benefits this would offer students. Rather than having to have their laptops plugged in for most of the day, they could plug their laptops in for just a few minutes. This would provide them with an entire day's worth of battery!

EDIT: corrected density stats

[eightbt]

That doesn't sound that amazing.  According to Wikipedia, the energy density of Lithium-Ion batteries is 160 Wh/kg.  (Of course it doesn't say what kind of Lithium-Ion battery that's for.)  But if these numbers are right, you'd need a battery that weighs more than twice as much to get the same amount of battery life!

XO Laptop: educational tool + exercise equipment?

[cmonkey]

Indeed.  A perfect battery doesn't exist.  There are always energy density vs usable-life vs charge time tradeoffs. 

While lithium-ion batteries have the best density, they have shorter lifetimes and tend to explode.  LiFePO4s are more stable and last longer, but have slightly lower energy density.  NiMHs are cheap, but get damaged when they are charged or drain too far, and tend to drain when not in use.

The best one to choose depends on the specifics of the product, but LiFePO4s seem to be the best fit for XOs.

Its likely that as Toshiba continues development, energy density will improve though, so this new battery is something to watch.

[isnbase]

Can i use the third party battery ( for example: toshiba battery at http://www.sales-battery.com/laptop-batteries/toshiba.htm) for  the laptop?