4ah high power battery repair

[Mockbubbles]

Hello, I've come across 10 faulty festool 4ah high power batteries from late 2019 to early 2021. most of them just need a new cell put in but I have 3 with BMS failures (all cells are good but the BMS just refuses to output even once i've charged the cells manually). Does anyone know if removing the BMS from a working battery to put on these BMS failed batteries will kill the BMS? I've found talk online about the BMS killing itself if it sees 0v and would like to know if this is actually true

I must say the 4ah are extremely well built and cell failures seem to be in random positions so at least festool has done a good job with designing the boards.

Thanks for any help

 

[Cheese]

Recently I had a 4.0 HPC battery pack, dated 11/2020 go bad. It refuses to charge even though 2 of the green LED's still light up. I sent it back to Festool for warranty consideration but that was a no-go. I mentioned in a brief note to Festool Service that the battery probably had fewer than 15 charge cycles on it which I'm sure they were able to verify.

I know this doesn't answer your question but just thought I'd bring it up to see if my battery issue was similar to yours. This is the FIRST Festool battery I've ever had a problem with.