48s at 3.2v

Hey all. Ok i know everything just ask my 2 exwifes. I am well beyond my abilities so i hired a company to set up my solar. However they wont build my battery bank. I am told by someone with 20yr in the field. He said the way i need to wire my bank is in 3 banks of 16 at 48v at 300ah. I do believe him however i want to dot my i and cross my t. He said that ah is no concern and 300ah is the only way to keep my 48v banks. I am confused i thought parallel did not effect v so why will putting my 16sbank at 48v diminish when i hook up the parallel part. Once i have my series hooked up at 48v why will the parallel lower my v? I will have 15kw in the bank configuration of 16s in series at 48v(x3) but only have 300ah because i did not put any parallel connections. I am so confused, i thought ah is longevity.

Hello,
- do you plan to use 48 x 100Ah@3.2V LiFePo4 cells ?
- do you mean 16S3P setup ? => (16 cells in series) in parallel with (16 cells in series) in parallel with (16 cells in series) ?
In that case you get (100Ah@51.2V + 100Ah@51.2V +100Ah@51.2V) = 300Ah@51.2V = 15360 Wh = 15.36 KWh
and you need 3 BMS.
-------------------------------------------------------------------------------------
- If you mean 3P16S setup => 16 x (3 cells in parallel) in series
In that case you get 16 x (300Ah@3.2V) = 300Ah@51.2V = 15360 Wh = 15.36 KWh
but you just need 1 BMS
-------------------------------------------------------------------------------------
>> there are trade-offs and pros and cons to either configuration <<

Pierrot said:

Hello,
- do you plan to use 48 x 100Ah@3.2V LiFePo4 cells ?
- do you mean 16S3P setup ? => (16 cells in series) in parallel with (16 cells in series) in parallel with (16 cells in series) ?
In that case you get (100Ah@51.2V + 100Ah@51.2V +100Ah@51.2V) = 300Ah@51.2V = 15360 Wh = 15.36 KWh
and you need 3 BMS.
-------------------------------------------------------------------------------------
- If you mean 3P16S setup => 16 x (3 cells in parallel) in series
In that case you get 16 x (300Ah@3.2V) = 300Ah@51.2V = 15360 Wh = 15.36 KWh
but you just need 1 BMS
-------------------------------------------------------------------------------------

>> there are trade-offs and pros and cons to either configuration <<

Click to expand...

Wow huge! Yes...... i am bing told no parallel just series = 300ah at 48v. I get that however i am bing told that if introduce a parallel connection i will lose my 48v in the the three banks of 16s in series that gives me my 48v. I have 48 3.2v 100ah deep cycle lifepo4 in series + parallel and keep my 48v and the 15.36kwh?

Kouros said:

i am bing told no parallel just series = 300ah at 48v.

Click to expand...

Sorry, it is impossible, "no parallel just series" = 48 cells in series = 48 x 100Ah@3.2V = 100Ah@153,6V !

The only one way to build à 300Ah@48V bank with all cells in series is to connect 16 300Ah@3.2V cells in series :
=> 16 x 300Ah@3.2V in series = 300Ah@51.2V = 15360 Wh = 15.36 KWh

Pierrot said:

Sorry, it is impossible,

Click to expand...

What about 3P16S? Thats 48v with 48 cells. And a single 16S BMS.

MisterSandals said:

What about 3P16S? Thats 48v with 48 cells. And a single 16S BMS.

Click to expand...

3P16S is not "no parallel just series"

MisterSandals said:

What about 3P16S? Thats 48v with 48 cells. And a single 16S BMS.

Click to expand...

This would work? I do have a bms for each pack of 16s.

Kouros said:

This would work? I do have a bms for each pack of 16s.

Click to expand...

Of course it would work.

Pierrot said:

Of course it would work.

Click to expand...

Thats a GREAT link to help out!

Pierrot said:

- If you mean 3P16S setup => 16 x (3 cells in parallel) in series
In that case you get 16 x (300Ah@3.2V) = 300Ah@51.2V = 15360 Wh = 15.36 KWh
but you just need 1 BMS

Click to expand...

Ah geez, sorry i missed this, you had everything all worked out. Carry on, bye.

MisterSandals said:

Ah geez, sorry i missed this, you had everything all worked out. Carry on, bye.

Click to expand...

Should have been obvious Captain!

Sorry, couldn’t help myself ?