How many Parallel 12V230Ah (Built-In 200A BMS) Safely & Practically?

[sun_of_a...]

Hello,

Thanks for the forum! This is regarding these: "LiTime 12V 230Ah Plus Low-Temp Protection LiFePO4 Battery, Built-In 200A BMS, Max 2944Wh Energy"

How many of these can be safely and practically put in parallel for a 12v battery bank? I've got 16 of them I was going to put in 4s4p, but thanks to the forum, I'd like to explore other scenarios now.

One practical issue with 12v is cable size. Note, PV would not necessarily need to go directly to this battery bank, nor would AC necessarily need to come directly from it. Maybe those are secondary issues.

The question now is how many of these can I safely and practically (wire size, buses, fuses, etc. Other?) put in parallel? And if anyone has a rough estimate of the cost of cables, fuses, buses, etc., it would be appreciated too.

Thanks for the forum!

edit
By the way, I'm leaning away from 4s4p because of the issue of imbalance among the cells. Does that issue just start coming back with 12v parallel in this case? Then there's a 24 volt bank to consider. I'm trying to minimize the imbalance potential now, and that's the nature of my question at this point. Thanks.

 

[sunshine_eggo]

Hello,

Thanks for the forum! This is regarding these: "LiTime 12V 230Ah Plus Low-Temp Protection LiFePO4 Battery, Built-In 200A BMS, Max 2944Wh Energy"

How many of these can be safely and practically put in parallel for a 12v battery bank? I've got 16 of them I was going to put in 4s4p, but thanks to the forum, I'd like to explore other scenarios now.

Most diagrams/manufacturers typically show no more than four strings in parallel.

One practical issue with 12v is cable size. Note, PV would not necessarily need to go directly to this battery bank, nor would AC necessarily need to come directly from it. Maybe those are secondary issues.

You aren't 12V. You're 48V.

The question now is how many of these can I safely and practically (wire size, buses, fuses, etc. Other?) put in parallel? And if anyone has a rough estimate of the cost of cables, fuses, buses, etc., it would be appreciated too.

4S4P is reasonable.

By the way, I'm leaning away from 4s4p because of the issue of imbalance among the cells. Does that issue just start coming back with 12v parallel in this case? Then there's a 24 volt bank to consider. I'm trying to minimize the imbalance potential now, and that's the nature of my question at this point. Thanks.

If you start by fully charging each of the 12V batteries to ensure they can all attain 14.4V without encountering over-voltage protection, and you install 12V balancers on each string, AND regularly charge your batteries to 57.6V at least once every week or two for 2 hours, you can minimize balance concerns.

 

[sun_of_a...]

Most diagrams/manufacturers typically show no more than four strings in parallel.



You aren't 12V. You're 48V.



4S4P is reasonable.



If you start by fully charging each of the 12V batteries to ensure they can all attain 14.4V without encountering over-voltage protection, and you install 12V balancers on each string, AND regularly charge your batteries to 57.6V at least once every week or two for 2 hours, you can minimize balance concerns.

Hi sunshine eggo, If I did want to stick with a 12v battery bank with these particular batteries, what's the most you would put in parallel for safety and practical reasons like wire size, buses, fuses, etc? Thank you

 

[sunshine_eggo]

Hi sunshine eggo, If I did want to stick with a 12v battery bank with these particular batteries, what's the most you would put in parallel for safety and practical reasons like wire size, buses, fuses, etc? Thank you

I wouldn't go 8P unless I had no other choice. I would look at fewer/larger 12V.

 

[sun_of_a...]

I wouldn't go 8P unless I had no other choice. I would look at fewer/larger 12V.

So, for a 12v battery bank with these 12v 230ah batteries, do you mean 7P max or 4P max? Thanks.

 

[sunshine_eggo]

So, for a 12v battery bank with these 12v 230ah batteries, do you mean 7P max or 4P max? Thanks.

Now if you're willing to get really nutty with your wiring and ensure that every single battery has exactly the same cable run to the charger/loads, you can go higher.

See link #6 in my signature. The bus bar option would be the best.

 

[sun_of_a...]

Now if you're willing to get really nutty with your wiring and ensure that every single battery has exactly the same cable run to the charger/loads, you can go higher.

I can imagine that keeping cable runs short AND the same length can be hard!

See link #6 in my signature. The bus bar option would be the best.

I will look at the Victron Wiring info, thank you!