Anyone did a successful recell on a T4x battery ?

[frankiepankie]

Hi guys,

I am always looking for nice projects with electronics.

I did some battery recell projects in the past, but they were sloppy (just slap in some cells parallel to the cells already in the battery, very bad because the cells don't match and you have an unstable battery)

I am expecting 4 pcs of near death T4x battery next week, and i also ordered a few 18650 cells from Dealextreme to put in the batteries. I have also ordered battery tabs (nickel strips) to connect the batteries together. But the thing i have been fighting with in the past were the electronics. I already tried recelling a T4x battery before, but i accidentally sparked the electronics when i connected the battery to my T40 for testing.

I got a near death T30 battery from someone and tried to change the cells on that one too. But when i connected a 2nd pack of cells (to keep the electronics powered during the swap), a wire snapped and the electronics locked itself When i connected it to my T40 (yes, i hear you thinking: What!? An T30 battery connected to an T40?? See this: http://forum.thinkpads.com/viewtopic.php?f=18&t=92776 ) i only got the fast blinking orange battery light, and the charge of the battery was 0%. Never got it to charge again.

The T30 battery had 2 microcontrollers on it: bq8011DBT and the bq29310PW

I found software (BE2Works, Smart Battery Workshop, AccPlus) to read the battery electronics. To read the battery electronics you need to build an i2c adapter, which is quite easy to build: http://sbworkshop.com/i2c.jpg

But unfortunately all the software i used doesn't have support for the bq8011DBT or the bq29310PW. So at the moment i am lost, and the T30 battery will never wake up from his death. I am hoping that the T4x batteries i receive next week have electronics that are supported by the software, so i can make it look like new, because with the software you can reset the cycles, full charge capacity and such.

The best method is to swap the cells when the battery still has some life in it. Even if you don't succeed at resetting the electronics, it will still work because the electronics will learn the new capacity after a few cycles. But the most important thing is to keep the electronics powered during the swap. Otherwise you will have the same problem as what i had: Electronics lost power, battery electronics locked = battery can be thrown away.

I will let you guys know if i succeeded with the T4x battery recell, but for the moment i am interested if anyone else has tried this. Please let me know your experiences!

[poshgeordie]

I'd be very careful recelling since there's a real fire risk.

See this post for detailed information: http://forum.thinkpads.com/viewtopic.php.......p525423.