#### TommyHolly

##### Solar Enthusiast

- Joined
- Jun 24, 2021

- Messages
- 207

Hey everyone,

My system is almost ready to put back together. I’m trying to figure out how to match the cells together and follow the advice I was given here. Any advice on the order?

I’m designing a 12v 1,200Ah 3P 4S system with four batteries. Each 12v 300Ah battery has 12 cells and the entire system is comprised of four batteries of 48 cells total, making a 12v 1,200Ah system. The cells are CALB brand, 3.2v 100Ah LiFePo4

Per everyone’s advice, I charged and performed a capacity test on each and every single cell over the last few weeks. I now have an order of my worst cell at 82.893Ah to my best cell at 90.345Ah. The vast majority of them are approximately 84-&5Ah each.

Here is an excel chart of the way I’m designing the system:

I was told to match the best cell with the worst one. However, I have 3 cells in parallel and the other groups of 3 form a 12v battery for the 4S part. Here is my guess. I’ll label the parallel ones in parentheses and a dash for the 4S series connections.

Battery One: (1, 48, x) - (5, 44, x) - (9, 40, x) - (13, 36, x)

Battery Two: (2, 47, x) - (6, 43, x) - (10, 39, x) - (14, 35, x)

Battery Three: (3, 46, x) - (7, 42, x) - (11, 38, x) - (15, 34, x)

Battery Four: (4, 45, x) - (8, 41, x) - (12, 37, x) - (16, 33, x)

What do I do with cell #’s 17 through 32??

Do I match the cells in a completely different way instead? I’m guessing I follow that same order and drop cell #17 together wity #1 and #48?

The final version may look like this…

Battery One: (1, 48, 17) - (5, 44, 21) - (9, 40, 25) - (13, 36, 29)

Battery Two: (2, 47, 18) - (6, 43, 22) - (10, 39, 26) - (14, 35, 30)

Battery Three: (3, 46, 19) - (7, 42, 23) - (11, 38, 27) - (15, 34, 31)

Battery Four: (4, 45, 20) - (8, 41, 24) - (12, 37, 28) - (16, 33, 32)

How does that look?

My system is almost ready to put back together. I’m trying to figure out how to match the cells together and follow the advice I was given here. Any advice on the order?

I’m designing a 12v 1,200Ah 3P 4S system with four batteries. Each 12v 300Ah battery has 12 cells and the entire system is comprised of four batteries of 48 cells total, making a 12v 1,200Ah system. The cells are CALB brand, 3.2v 100Ah LiFePo4

Per everyone’s advice, I charged and performed a capacity test on each and every single cell over the last few weeks. I now have an order of my worst cell at 82.893Ah to my best cell at 90.345Ah. The vast majority of them are approximately 84-&5Ah each.

Here is an excel chart of the way I’m designing the system:

I was told to match the best cell with the worst one. However, I have 3 cells in parallel and the other groups of 3 form a 12v battery for the 4S part. Here is my guess. I’ll label the parallel ones in parentheses and a dash for the 4S series connections.

Battery One: (1, 48, x) - (5, 44, x) - (9, 40, x) - (13, 36, x)

Battery Two: (2, 47, x) - (6, 43, x) - (10, 39, x) - (14, 35, x)

Battery Three: (3, 46, x) - (7, 42, x) - (11, 38, x) - (15, 34, x)

Battery Four: (4, 45, x) - (8, 41, x) - (12, 37, x) - (16, 33, x)

What do I do with cell #’s 17 through 32??

Do I match the cells in a completely different way instead? I’m guessing I follow that same order and drop cell #17 together wity #1 and #48?

The final version may look like this…

Battery One: (1, 48, 17) - (5, 44, 21) - (9, 40, 25) - (13, 36, 29)

Battery Two: (2, 47, 18) - (6, 43, 22) - (10, 39, 26) - (14, 35, 30)

Battery Three: (3, 46, 19) - (7, 42, 23) - (11, 38, 27) - (15, 34, 31)

Battery Four: (4, 45, 20) - (8, 41, 24) - (12, 37, 28) - (16, 33, 32)

How does that look?