LFP Powerwall

[Japera]

I have 3.2v 280 Ah cells. There are plenty of threads in the DIY LiFePO4 Battery Banks subforum of sources to get them from.

I don't want to use premade. I want to use individual cells and build it. Is that 3.2v 280Ah hooked up in series? Do they state how many individual 3.2v are in that pack?

 

[Japera]

Or, you could get cells with higher Ah ratings.

I've seen some 3.2v 15Ah individual cells.

 

[Japera]

which way would arrange my 16 batteries to solder in diagram 1 or diagram 2?

 

[HRTKD]

I don't want to use premade. I want to use individual cells and build it. Is that 3.2v 280Ah hooked up in series? Do they state how many individual 3.2v are in that pack?

Everything discussed in that subforum is DIY, as in taking individual cells and making a 12v, 24v or 48v battery out of them.

My battery is a 4s configuration made up of four 3.2v 280Ah cells.

 

[Ampster]

And that's where im stuck. There is a disconnect for me. If I put 16 in parallel I'd have 3.2v 96Ah and is I put four of those in series I'd have the 12v 96Ah?

3.2volts at 96 Ahrs is 307.2 Watthrs.
12.8 volts at 96 Ahrs is 1228.8 Watthrs.
Does that help you get unstuck?

 

[Jejochen]

I added the 7th bank today. Now all the space is used, and i have a 100.3 kWh battery!

 

[Jejochen]

An update on my system:
Today i noticed a leaking cell. On inspection the cell is completely swollen and sounds hollow when tapping on it.
Hope this not the start of a tsunami of bad cells...

 

[Supervstech]

An update on my system:
Today i noticed a leaking cell. On inspection the cell is completely swollen and sounds hollow when tapping on it.
Hope this not the start of a tsunami of bad cells...
View attachment 68581

Is the vent blown?

 

[curiouscarbon]

Thank you for sharing. Sorry that it will need repair.

I too hope that it is an isolated issue.

Please wear PPE and if you find the leak origin please share photos if you are comfortable to.

 

[Jejochen]

Is the vent blown?

Nope

Will post pictures when serviced

 

[solardad]

@Jejochen bummer! Just seeing this now. Any updates?

 

[Ironman]

Very nicely done.
I noted that on both batteries you do not have any compression on the pack. Do you find the pack swelling or is it unnecessary?

 

[curiouscarbon]

Very nicely done.
I noted that on both batteries you do not have any compression on the pack. Do you find the pack swelling or is it unnecessary?

dear @Ironman i am not familiar with this build entirely because did not build. there seems to be a threaded rod in the image most recently posted


the two grey lines running from lower left to upper right appear to be a threaded rod that may provide compression for the overall pack.

hope this helps, sorry if i’m way off base here

 

[Ironman]

the two grey lines running from lower left to upper right appear to be a threaded rod that may provide compression for the overall pack.

hope this helps, sorry if i’m way off base here

No, you are right. I never saw the rods, his build is so nice, I should have looked for them.