NiMH Rebuild?
 

Anyone here done a NiMH rebuild? I have some ancient batteries from '01 (they literally have the ACROS code name on them) that I'd like to take a stab at rebuilding but would love any advice.

Also have a set of Lithiums that were "rebuilt" by MTO, but only throw red lights.

https://youtu.be/kAdzSqDfChc
Don't open the case like he did though

Often with the nimh batteries the chemicals will corrode the bms board.

some repairs can be made but they start to conduct internally along the vias inside then pcb.. and eventaully fail,...so even with new cells it won't work.

I have new boards just waiting to be built and tested...as I use nickel cells alot I don't want to be without.

However, it is often just the cells that are unservicable..

best...

Hi Dorrington,
Im about to rebuild a NimH pack. What are you using to glue batteries. Epoxy
or Hot glue or what. Any advice appreciated.
Thanks
Les

Hi Dorrington,
What glue do you use to stick battery packs together?. In the originals it looked like some kind of epoxy.
Thanks
Les

Hi Les,

I usually tape around the packs of ten just to hold them together.

I use polyeurethene re-enterable potting compund (just enough to cover the bottom of the cells 1/4" or so).

seems to work for me...

....And to re-seal the lids I use Sikafkex 221...and a soapy wet finger to finish the seal....

Hi Dorrington,
Thanks for that. The compound you use is this just smeared on the bottom of
the 10 pack to make them solid.
I was considering using Araldite. As the machine will cause considerable vibration i wanted to make sure these cells will not move.
What are you using to cement the 10 packs to the cases?.
How long have you been using your method for? Have you encountered any
problems with you rebuilds done this way.
Sorry for all the questions but are about to start.

Have you come up with a sensible priced replacement for the L/H grip. Or know of a reasonably priced replacement. For
a Gen 1 unit.
Thanks
Regards
Les

Hi Les.

I pour in the re-enterable encapsulation compound until the bottom 1/4 inch or more is covererd.

this holds everything real tight but still lets the cells expand if required as they heat up.

Also if you need to you can dig the cells out

I use this.

https://www.elichem.co.uk/image/cata...data_sheet.pdf

Hi Dorrington,
Very much appreciate your comments. Just to recap your procedure is
1. Wrap the wired 10 packs with tape and drop the 12 into the case.
2. Pour in the potting mix so you have about a 1/4" covering the packs.

Have you welded your connections or soldered?.
Thanks again
Regards
Les