Existing 24V battery...and the Tesla module

[Selagor141]

Hi all,

Hope you can help with figuring this one out.

I have an existing battery system. It is a DIY 2x 7s80p, 24V. I'm thinking about purchasing a Tesla module (5.3 KWh). Is there a way to connect both of them into one system? I believe Tesla is 6s 24V which works in different voltage ranges.

Please help

 

[OffGridInTheCity]

Hi all,

Hope you can help with figuring this one out.

I have an existing battery system. It is a DIY 2x 7s80p, 24V. I'm thinking about purchasing a Tesla module (5.3 KWh). Is there a way to connect both of them into one system? I believe Tesla is 6s 24V which works in different voltage ranges.

Please help

I agree - I also think Tesla modules are 6s. Can you reconfigure your dual 7s80p to a 5.4kwh 6s configuration? At 2000mah/cell average that would be 6s125p kind of thing. This would give you 2 batteries to parallel that would be pretty well matched in capacity.

 

[JoannaLannie]

I think as long as the two battery packs doesn't differ too much in capacity then paralleling them will be fine as long as the voltages match. Looking forward to sharing in the future.

 

[floydR]

The voltage of a 7S (25.2V-25.9V nominal)and a Tesla 6S (22.8V nominal ) don't match.
later floyd

 

[Selagor141]

I agree - I also think Tesla modules are 6s. They are about Can you reconfigure your dual 7s80p to a 5.4kwh 6s configuration? At 2000mah/cell average that would be 6s125p kind of thing. This would give you 2 batteries to parallel that would be pretty well matched in capacity.

Yes, that was my initial plan. I was just trying to figure out if there are other ways

 

[Selagor141]

I think as long as the two battery packs doesn't differ too much in capacity then paralleling them will be fine as long as the voltages match. Looking forward to sharing in the future.

In theory my two packs (7s80p) should have around 4KWh each. In practice, more like 3KWh. In comparison to Tesla module there will be a bit of un-balance capacity

 

[Crimp Daddy]

The right (and simple) answer is NO.

But if you tried to make it work, you would have to create a narrow voltage window to operate within. For example 21v min to 25v max.

Both packs would be a different SOC
You would loose total usable capacity

 

[Selagor141]

The right (and simple) answer is NO.

But if you tried to make it work, you would have to create a narrow voltage window to operate within. For example 21v min to 25v max.

Both packs would be a different SOC
You would loose total usable capacity

Thank you for all your suggestions. I will redo the packs as 6s80p and then connect the Tesla pack. Will keep you updated

 

[dali1972]

Thank you for all your suggestions. I will redo the packs as 6s80p and then connect the Tesla pack. Will keep you updated

I have a good module going spare if you need it. Also your probably aware that you would need to try balance the cells aswell... otherwise the top and lower cell voltage delta will also cause issues