First DIY 302ah 48v battery.

Hi all,
I want to build my own LIfePo4 battery bank to use as a UPS/backup during power outages. I'll likely be using the EG4 6500 EX as my inverter. I was looking at

Set of Four Matched LiFePO4, 302AH, 3.2V Lithium Prismatic Cells With Welded Studs​

for $889. Can I start with just 4 cells and add more later? Most of the BMS's seem to be for 16s setups not 4s for 48v systems. Is there any issue with that? What BMS would I use for something like that?

You need 16 cells to make a 48V battery.

mikelaaz said:

Hi all,
I want to build my own LIfePo4 battery bank to use as a UPS/backup during power outages. I'll likely be using the EG4 6500 EX as my inverter. I was looking at

Set of Four Matched LiFePO4, 302AH, 3.2V Lithium Prismatic Cells With Welded Studs​

for $889. Can I start with just 4 cells and add more later? Most of the BMS's seem to be for 16s setups not 4s for 48v systems. Is there any issue with that? What BMS would I use for something like that?

Click to expand...

4 cells is only 13.8V

So, you can start with just the 4, and build a 4s 13.8V pack, learn with it, then buy 3 more sets when you are ready for a 48V...

mikelaaz said:

Hi all,
I want to build my own LIfePo4 battery bank to use as a UPS/backup during power outages. I'll likely be using the EG4 6500 EX as my inverter. I was looking at

Set of Four Matched LiFePO4, 302AH, 3.2V Lithium Prismatic Cells With Welded Studs​

for $889. Can I start with just 4 cells and add more later? Most of the BMS's seem to be for 16s setups not 4s for 48v systems. Is there any issue with that? What BMS would I use for something like that?

Click to expand...

Simply buy 4 of those $899 packs to run the 6500 and a 16s BMS. Think you can find better deals on those sells though.

mikelaaz said:

Hi all,
I want to build my own LIfePo4 battery bank to use as a UPS/backup during power outages. I'll likely be using the EG4 6500 EX as my inverter. I was looking at

Set of Four Matched LiFePO4, 302AH, 3.2V Lithium Prismatic Cells With Welded Studs​

for $889. Can I start with just 4 cells and add more later? Most of the BMS's seem to be for 16s setups not 4s for 48v systems. Is there any issue with that? What BMS would I use for something like that?

Click to expand...

You can start with a 12 volt system. I did this. It ended up costing a lot more in the long run. When you go from 12 to 48 volts, you have to buy a lot of things again. I started with FLA batteries which were useless after 3 years and had to buy the inverter, and the charge controller again.

I learned a lot by going through this process, so it wasn't a total loss.


I bought a 12s Apexium case with BMS, 16 304 AH cells, 2 cables, and a RS485 adapter to monitor the battery with my computer for $2550. This was through Jenny Wu at Docan Power.

I would find a better price, I just paid about $100.00 per cell for EVE 304ah matched IR with test report, you do have to wait for the boat though.