Thinkpads Forum

thought this was interesting.

http://www.electronics-lab.com/articles ... index.html

This is what caught my eye

Quattro wrote:thought this was interesting.

http://www.electronics-lab.com/articles ... index.html

Most of the Thinkpads seem to use the older-style cylindrical LiIon cells. These often require a bit less work to assemble, although soldering them in series can be tricky.

Does anyone know what would happen if higher-capacity batteries were inserted in place of the originals? For large, flat packs, lithium-ion-polymer cells would offer a very high-capacity alternative.

The only thing that might be risky to put the li-polymer batteries into the original shell is that the recharging/monitoring control circuit board was designed for li-ion batteries. It's hard to say what would happen during the recharging process on the new batteries. I also found an interesting site a while ago about how to change the EEPROM content on the circuit board.

http://gimel.esc.cam.ac.uk/james/resources/tp240bat/

spasticteapot wrote:Most of the Thinkpads seem to use the older-style cylindrical LiIon cells. These often require a bit less work to assemble, although soldering them in series can be tricky.

Does anyone know what would happen if higher-capacity batteries were inserted in place of the originals? For large, flat packs, lithium-ion-polymer cells would offer a very high-capacity alternative.

Higher capacity cells of the same type shouldn't be a problem - you see that now (e.g., you can get a 4400mAh pack for a TP600 series, whose original factory battery was rated at 3200).

Switching to a different type is trickier - the charging requirements may change (for example, NiCd and NiMH are charged differently, and the circuits for one are not compatible with the other). Not knowing how LiPol's charging requirements differ from LiIon's, I'd say it might not work, or at least you might end up with a pack that you can't recharge in the computer (not very useful, that).

Rob