Replacing some 26650 Cells

[Corty8]

Hi All

so I have what's called a GS7000 battery that I have discovered had a pack that was down to about 2v while the rest are all between 3.22v and 3.32v so I have removed that one pack and discovered a number of cells that are leaking

Now I am the first to admit I am a little out of my depth here as I am in IT refurbishing but I do have a little SWM-10 battery spot welder that I use on single coin cells to make BIOS batteries so hoping that will be strong enough?

There is not much on these cells in regard to branding other than the code IFR26650E3400, I have found these cells which are pretty close:

商品详情

item.taobao.com

I would appreciate if someone could have a quick look and see if these would be ok

I was kind of thinking I may as well just rebuild the entire pack rather than try and reuse the ones that are not leaking, is that the best option?

Also I have read that cells need to be balanced, will I need to charge all the new cells up to 3.2v to match the rest of the packs?

Sorry for all the questions but prefer to ask first than be wrong later

Cheers

 

[zcskywire2]

There is not much on these cells in regard to branding other than the code IFR26650E3400, I have found these cells which are pretty close:

Shenzhen BST Power IFR26650E3400's, you can find the cell datasheet in the resources section. They are a bog standard budget Iron Phosphate 26650 cell.

商品详情

item.taobao.com

I would appreciate if someone could have a quick look and see if these would be ok

They will probably work, THLB is not a well known manufacturer and I have no experience with them. Some other brands to look into: PLB (Power Long Battery), JGNE (Shangdong Goldencell Electronics Techonolgy), CBAK (China Beligum New Energy), EVPS (Anhui Levineng Power Battery)
and LongTTech. These are the bigger names in the space, many wont sell direct but they will show up on Alibaba. You would be looking for a simple energy cell so skip cells like the PLB IFR26650-25B.

I was kind of thinking I may as well just rebuild the entire pack rather than try and reuse the ones that are not leaking, is that the best option?

With the condition of the pack, I would say yes. It will be added cost and work.

Also I have read that cells need to be balanced, will I need to charge all the new cells up to 3.2v to match the rest of the packs?

Yes the cells will need to be balanced. You can balance all the cells that are in parallel at the same time once they are welded together. it will just take longer