48V battery bank with 12V 100AH batteries

[CamboMoods]

Hi all,

I am looking to create a battery bank using the following batteries:

VoltaX 12V 100Ah LifePO4 Lithium Batteries

I am wanting to create 2 banks of 400AH at 48V (I have 8 of them) and am wondering what would be the best way to cable them?
Also, do I need an additional BMS? the place I bought them from states they have them built-in and that I can have up to 4 in Series and unlimited in parallel

here are the battery specs from the seller's website:

SPECIFICATIONS​

	VoltaX 12v 100Ah
Nominal Voltage	12.8V
Nominal Capacity	100Ah
Usable Capacity	100Ah
Energy	1280Wh
Charge time	2-4 hours
Weight	Approx. 9.5kg
Charge Voltage	14.6V
Discharge Cut-off Voltage	10V
Standard Charge Current	20A
Max. Charging Current	50A
Max. Continuous Discharge Current	50A/0.5C Rating
Max. Discharge Current 5 Seconds	125A/1.25C Rating
Cycle Life	2000 times
Internal Impedance	≤50mmΩ
Dimensions	L 330.3 x W 173.4 x H 215.6mm
Working Temperature Range Charge	-20C--60C
Storage Temperature	-10C--50C

 

[snoobler]

The max discharge current of 0.5C is half of what is typical, yet they are still only rated for 2000 cycles. The internal resistance of 50mΩ is also suspect. It should be much lower - more like 3. The internal resistance of this battery is higher than a lead acid battery. This immediately flags it as an inferior product to more expensive but trusted brands and most DIY efforts. Thus all claims made by the manufacturer deserve greater scrutiny.

IF *I* chose to buys these batteries, I would test all 8 of them to verify they meet capacity and internal resistance.

The only way you can install a BMS is if you can open the batteries and attach it to the individual cells. If they have a BMS as they claim, you shouldn't need more.

Are you 100% certain that 10kWh of battery capacity is what you need as the result of a complete energy audit? If not, link #5 in my sig to obtain solar hours for your location, panel orientation and tilt. Link #1 for the energy audit.

 

[CamboMoods]

Thank you for the assistance, these are a starting point for us due to budget and I'm still learning!