Jump to content

Lifepo4 battery from salvaged cells


ErichK

Recommended Posts

Morning all. I have 14 120ah lifepo4 cells from an old 15 cell 48V battery, 1 cell failed. I am considering building a 360ah 12V battery using 12 of the good cells to use in a mobile application with a 12V 1500W inverter that I have lying around. Can the forum please assist with:

1. Recommend a BMS?

2. Recommend a charger?

3. Recommend a balancer?

4.Protection requirements for a safe system?

5. Best/safest configuration? I.e 3 x parallel cells then 4 sets in series, or 4 x series cells and 3 sets in parallel.

5. Housings? Thinking of a timber box?

I'm sure someone has built this before, looking forward to the info.

Thanks In advance.

Link to comment
Share on other sites

Hi Erich, 

I would recommend a JK BMS (as example JK-B1A8S20P) with built in, Bluetooth and active balancer. PM me if you are interested in a BMS.

For safety/protection at least add a DC circuit breaker and suitable DC fuse. 

If grouping the cells correctly (to optimize capacity) a 3P4S setup should work well. 

Included some ideas for housing/enclosure/compression from a 24V @280Ah build that my son did. He used a 300A JBD BMS with 1A balancing and relay disconnect.

3mm EVA foam was used between the cells and some yellow fibre sheets as protection between the metal rods and plates during compression. PVC pipe to cover the rods would even have been better. 

Also see included DC terminals that can be used. 

Enjoy the DIY project... 

Blessings, Deon 

IMG-20230420-WA0004.jpg

IMG-20230417-WA0009.jpg

IMG-20230401-WA0000.jpg

20230521_124742.jpg

Link to comment
Share on other sites

5 hours ago, DeonBez said:

Hi Erich, 

I would recommend a JK BMS (as example JK-B1A8S20P) with built in, Bluetooth and active balancer. PM me if you are interested in a BMS.

For safety/protection at least add a DC circuit breaker and suitable DC fuse. 

If grouping the cells correctly (to optimize capacity) a 3P4S setup should work well. 

Included some ideas for housing/enclosure/compression from a 24V @280Ah build that my son did. He used a 300A JBD BMS with 1A balancing and relay disconnect.

3mm EVA foam was used between the cells and some yellow fibre sheets as protection between the metal rods and plates during compression. PVC pipe to cover the rods would even have been better. 

Also see included DC terminals that can be used. 

Enjoy the DIY project... 

Blessings, Deon 

IMG-20230420-WA0004.jpg

IMG-20230417-WA0009.jpg

IMG-20230401-WA0000.jpg

20230521_124742.jpg

That looks great thank you. Definitely going to plagiarize it. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...