Just got a new set of LiFepo4 that I want to use together with my 1yr old pack

[GerardJacinto]

I have been using a pack of 8 120ah Higee lifepo4 batteries in series 24v config for a little over a year now. I wanted to increase my pack capacity and so just recently, I acquired a new set of 8 of the same battery.

My questions are:

1. Now that I have 16 pcs of the same 120ah Higee lifepo4 battery ( half is a year old and half is brand new ), can I put them in a 2p8s configuration to retain a 24v config?

2. Is it safe to do so? If not,

3. Should I just set the new batteries as their own pack with their own BMS and parallel it to my current pack? If yes,

4. Is it alright to use a lower rated BMS like a Daly 150A? I cant source the same 200A locally, so the price difference between 150A and 200A is quite substantial.

My current pack is managed by a Daly 200A BMS btw, connected to a 60A MPPT SCC, and a 3kW inverter.

Thanks.

 

[sunshine_eggo]

2. Mostly, but not ideal.

3. Yes.

4. If you won't ever pull more than ~250A total from both batteries, yes.

Connect the two batteries in parallel via best practices (refer to Victron Wiring Unlimited). Once deployed, under high load, use clamp ammeter to confirm that both batteries are sharing the current as equally as possible or at least within the operating limits of both batteries.

 

[Ellcon123]

You should create as individual packs with own BMS and place in parallel. Will run fine.