NewStats: 3,259,806 , 8,170,932 topics. Date: Monday, 26 May 2025 at 04:18 AM 5h5u5

This is one of the best threads on Nairaland that I’ve seen. But I couldn’t find any post here that shows a step-by-step explanations on how to build a pack. It’s as though everyone here already knows how to connect your batteries in the right configurations, how to choose the right BMS for your pack and connect your battery terminals to a BMS, and how to create terminals for charging the battery. That would have cemented the whole knowledge.

BigDickProblems:
This is one of the best threads on Nairaland that I’ve seen. But I couldn’t find any post here that shows a step-by-step explanations on how to build a pack. It’s as though everyone here already knows how to connect your batteries in the right configurations, how to choose the right BMS for your pack and connect your battery terminals to a BMS, and how to create terminals for charging the battery. That would have cemented the whole knowledge.

Probably you didn't read from page 1.

dollarnaira:


Probably you didn't read from page 1.

I did, but it was only pictures, and no explanations. I for instance have issues understanding the battery configurations and how to tell what type of BMS will work for the configurations you use(e.g When they say 4S2P). I understand perfectly what a parallel and series connection is from my Physics textbook, however, I have no idea about it when it comes to arranging multiple cells like you guys do.

I only think of it from one perspective (the way we were taught in Physics class), and this is where my problem is. Even if I come with an open mind it still confuses me.

For instance, I know how to explain to you that a 128Wh system using a 3.2V 5Ah batteries can be built this way (attached image). You can see that my batteries are arranged in series in two sections to get the 12.8V (I.e 3.2V *4) and keep 5AH the same for each cells. Then the two sections are now ed in parallel to keep the 12.8V and increase the AH to 10AH( I.e 5Ah * 2).

So this is my problem—it is the only perspective I see it from. But you guys arrange all these cells as a bundle and create connections that I can’t just understand no matter how hard I try. To make it worse I start hearing 4S2P, like how 🥲?)

BigDickProblems:


I did, but it was only pictures, and no explanations. I for instance have issues understanding the battery configurations and how to tell what type of BMS will work for the configurations you use(e.g When they say 4S2P). I understand perfectly what a parallel and series connection is from my Physics textbook, however, I have no idea about it when it comes to arranging multiple cells like you guys do.

I only think of it from one perspective (the way we were taught in Physics class), and this is where my problem is. Even if I come with an open mind it still confuses me.

For instance, I know how to explain to you that a 128Wh system using a 3.2V 5Ah batteries can be built this way (attached image). You can see that my batteries are arranged in series in two sections to get the 12.8V (I.e 3.2V *4) and keep 5AH the same for each cells. Then the two sections are now ed in parallel to keep the 12.8V and increase the AH ( I.e 5Ah * 2).

So this is my problem—it is the only perspective I see it from. But you guys arrange all these cells as a bundle and create connections that I can’t just understand no matter how hard I try. To make it worse I start hearing 4S2P, like how 🥲?)

We combine the cells first, then series.
From the above scenerio, we do 5+5 = 10a den series i.e 2p4s. It workes far better than the above. Just imagine 40 cells of 5a, do combine 10 cells together first i.e 10p (50a) in 4 different places, then series them i.e 4s.

In total you will get 10p4s solid piece instead of 4s10p.

BigDickProblems:


I did, but it was only pictures, and no explanations. I for instance have issues understanding the battery configurations and how to tell what type of BMS will work for the configurations you use(e.g When they say 4S2P). I understand perfectly what a parallel and series connection is from my Physics textbook, however, I have no idea about it when it comes to arranging multiple cells like you guys do.

I only think of it from one perspective (the way we were taught in Physics class), and this is where my problem is. Even if I come with an open mind it still confuses me.

For instance, I know how to explain to you that a 128Wh system using a 3.2V 5Ah batteries can be built this way (attached image). You can see that my batteries are arranged in series in two sections to get the 12.8V (I.e 3.2V *4) and keep 5AH the same for each cells. Then the two sections are now ed in parallel to keep the 12.8V and increase the AH to 10AH( I.e 5Ah * 2).

So this is my problem—it is the only perspective I see it from. But you guys arrange all these cells as a bundle and create connections that I can’t just understand no matter how hard I try. To make it worse I start hearing 4S2P, like how 🥲?)

If you still don’t understand let me know!!

iraybuju:



If you still don’t understand let me know!!

Pls I am still confused o 🥲
Infact I had to loosen my discarded laptop battery to make sense of the whole thing, then boom, the laptop own is understandable to an extent, infact I just used today trying to understand the ones you guys run here and I still don’t get it. Trying to unlearn something is difficult I guess.

I understand the mathematics around it, but I don’t understand why some connections need to be done at different ts and all that; the way you guys do yours.

dollarnaira:


We combine the cells first, then series.
From the above scenerio, we do 5+5 = 10a den series i.e 2p4s. It workes far better than the above. Just imagine 40 cells of 5a, do combine 10 cells together first i.e 10p (50a) in 4 different places, then series them i.e 4s.

In total you will get 10p4s solid piece instead of 4s10p.

Only if a diagram can come in, but I know it’s not possible due to the third Dimension.

We always deliver on our promise. We have been around for over 10years already

Fapemz:
We always deliver on our promise. We have been around for over 10years already

BigDickProblems:


Pls I am still confused o 🥲
Infact I had to loosen my discarded laptop battery to make sense of the whole thing, then boom, the laptop own is understandable to an extent, infact I just used today trying to understand the ones you guys run here and I still don’t get it. Trying to unlearn something is difficult I guess.

I understand the mathematics around it, but I don’t understand why some connections need to be done at different ts and all that; the way you guys do yours.

Go to YouTube and watch live demonstrations on what we are building then you will understand better

BigDickProblems:


Only if a diagram can come in, but I know it’s not possible due to the third Dimension.

See this
24p3s

24 cells welled together in group of 3
Then series them positive to negative, positive to negative.

Fapemz:
We always deliver on our promise. We have been around for over 10years already

This is a diy group
Please don't do this here.

dollarnaira:


See this
24p3s

24 cells welled together in group of 3
Then series them positive to negative, positive to negative.

852w?

officialfestus:
852w?

Roughly but will do capacity test today.

dollarnaira:


See this
24p3s

24 cells welled together in group of 3
Then series them positive to negative, positive to negative.

Boss Wow!

This just opened my eyes 😂
I understand now. Wow!

Please how can I get these cells and how much are each of them for a 12.8V system?

BigDickProblems:



Boss Wow!

This just opened my eyes 😂
I understand now. Wow!

Please how can I get these cells and how much are each of them for a 12.8V system?

These are lithium ion 3.7v per cell
Series will give 11.1v ( 3 cells )

Full charge is 4.2v per cell
Series = 12.6v ( still 12v system)

Lifepo4 is 3.2v per cell
Series 12.8v ( 4 cells )

Full charge is 3.50v per cell
Series 14.0v ( 12v system ).

Lithium ion 16v = 4s
Lithium ion 24v = 7s ( 7 cells )

dollarnaira:


Roughly but will do capacity test today.

OK, please do and update us.

dollarnaira:


These are lithium ion 3.7v per cell
Series will give 11.1v ( 3 cells )

Full charge is 4.2v per cell
Series = 12.6v ( still 12v system)

Lifepo4 is 3.2v per cell
Series 12.8v ( 4 cells )

Full charge is 3.50v per cell

Series 14.0v ( 12v system ).

Lithium ion 16v = 4s
Lithium ion 24v = 7s ( 7 cells )

I understand perfectly, pls how do I get these cells? Here in Lagos, Ikeja or Alaba? Any of them.

dollarnaira:


See this
24p3s

24 cells welled together in group of 3
Then series them positive to negative, positive to negative.

But on a closer look at the first image, why do you have 4 wires extended out from each of the 24p sets?

Cos I would expect just 2 wires (positive and negative extending out from your 24 parallel cells. Is there any reason for that?


Edited: ok i understand now, It doesn’t matter, so far all the negatives and positives from each 24P meets with the negatives and positives respectively on the other 24P sets right ?

BigDickProblems:


But on a closer look at the first image, why do you have 4 wires extended out from each of the 24p sets?

Cos I would expect just 2 wires (positive and negative extending out from your 24 parallel cells. Is there any reason for that?


Edited: ok i understand now, It doesn’t matter, so far all the negatives and positives from each 24P meets with the negatives and positives respectively on the other 24P sets right ?

Yes.
Top is positive
Bottom is negative

More cables, the better especially if your intention is to to heavy load.

The above powered a 100L freezer without stress.

dollarnaira:


Yes.
Top is positive
Bottom is negative

More cables, the better especially if your intention is to to heavy load.

The above powered a 100L freezer without stress.

Damn!

How much did it cost you to build? And what’s the capacity in WH?

.

dollarnaira:


Yes.
Top is positive
Bottom is negative

More cables, the better especially if your intention is to to heavy load.

The above powered a 100L freezer without stress.

Boss please kindly tell me how to get this 18650
I want to build some stuff with it
please abeg you bro

barezy:



Boss please kindly tell me how to get this 18650
I want to build some stuff with it
please abeg you bro

The guy is here o.
@Tetralogyfallot

BigDickProblems:


Damn!

How much did it cost you to build? And what’s the capacity in WH?

Testing at the moment

dollarnaira:


Testing at the moment

Nice 🙌

barezy:



Boss please kindly tell me how to get this 18650
I want to build some stuff with it
please abeg you bro

tetralogyfallot, he has them in stock.

dollarnaira:


Testing at the moment

why didn't you go for 24v since you have enough cells?

Machiny:
why didn't you go for 24v since you have enough cells?

Same result
By the way I don't have such inverter.

When a system works, it is fine.

500w inverter powering a freezer along with initial surge is amazing. Some 1.5kva cannot do it.

Machiny:
why didn't you go for 24v since you have enough cells?

Just 72 cells
10p7s = 70 cells.

dollarnaira:


Just 72 cells
10p7s = 70 cells.

should give same power as the 12v I guess? because from your 12v pack there is total of 72cells,

Machiny:
should give same power as the 12v I guess? because from your 12v pack there is total of 72cells,

You can drain more energy from the 12v than from the 24v. Cut off for the exact set up above is 9v while the cut off of the 24v is 21v ( with great capacity left undrained).