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24v 280AH Battery Bank Mounting

TrailAgent

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I am building a 24v 280AH battery bank that will be installed in a van conversion. The bank will consist of 8 cells and 1 24v Overkill BMS. For the ease of installation and possible removal, is there a problem with building two 12v banks and then connecting those banks with short 2/0 wires and still manage the combined banks with the single 24v BMS? Or, do I need to either: (a) connect all 8 cells with the same type of copper bus bars if I use the single 24v BMS; or (b) use two 12v BMS units?
 
Since its a van and vibration is a concern why not use cables for all the cell interconnects.
@Will Prowse has a video that indicates that 4 of these cells fit nicely in a milk crate.
Which is nice because 4 cells weighs ~50 pounds.
An idea I had recently is to just keep the cells in the low density foam that they ship in.
Maybe even in the cardboard box too.
I have not done the research to see if the foam is sufficiently heat tolerant to be safe.
cells_packaging.jpg
 
Since its a van and vibration is a concern why not use cables for all the cell interconnects.
@Will Prowse has a video that indicates that 4 of these cells fit nicely in a milk crate.
Which is nice because 4 cells weighs ~50 pounds.
An idea I had recently is to just keep the cells in the low density foam that they ship in.
Maybe even in the cardboard box too.
I have not done the research to see if the foam
That makes sense. I just found out that I actually have 4 Lishen 272AH and 4 EVE 280AH cells. Any advice on how to best mix them. Should each type be kept together?
 
That makes sense. I just found out that I actually have 4 Lishen 272AH and 4 EVE 280AH cells. Any advice on how to best mix them. Should each type be kept together?
First thing to do is please post a picture of the tops of all 8 cells.
We are here to help.
 
I am building a 24v 280AH battery bank that will be installed in a van conversion. The bank will consist of 8 cells and 1 24v Overkill BMS. For the ease of installation and possible removal, is there a problem with building two 12v banks and then connecting those banks with short 2/0 wires and still manage the combined banks with the single 24v BMS? Or, do I need to either: (a) connect all 8 cells with the same type of copper bus bars if I use the single 24v BMS; or (b) use two 12v BMS units?

No problem with 2 separate groups of 4 cells managed by 1 BMS as a 24v battery; I'm building my 560Ah 48v bank with 4 separate "boxes" .. as long as the wires are big enough and short enough, you won't have any big problems, especially because you have no cells in parallel.
 
Here they are: 272Ah silver center. 280ah blue center.
 

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That makes sense. I just found out that I actually have 4 Lishen 272AH and 4 EVE 280AH cells. Any advice on how to best mix them. Should each type be kept together?

Since this is a simple 8s system (no cells in parallel), it doesn't matter. Your battery capacity will simply be limited by your worst-performing cell. The BMS will take care of that. You might want to run a full capacity test so you know what to expect from the battery.
 
As @cinergi said you should run a capacity test on each cell.
I hope you didn't pay to much for the "last chicken in the shop".
We can probably make this work though to ~272 amp hours that is.
I got a good deal on the batteries so I’m ok with 272 ah. They were all new in the box and local pickup.
 
While the Ah difference between 272 and 280 is only 2.8%, wouldn't the 272 Ah cells get to their full charge slightly earlier than the 280 Ah cells?
 
While the Ah difference between 272 and 280 is only 2.8%, wouldn't the 272 Ah cells get to their full charge slightly earlier than the 280 Ah cells?

Not if they're top-balanced. Even differences in IR won't be a problem. A significant difference in efficiency (energy lost to heat) would be an issue, however.
 
This is my first build using these types of cells so I want to keep things as simple as possible. So, ended up getting 4 more 272ah cells. I’m going to build a 24v bank from the 8 272ah cells and a 12v bank from the 280ah cells. I’ll put the 24v bank in a van I’m converting and use 12v bank for a portable power supply just have one in case of a power outage. Two projects is better than one - right?
 
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