diy solar

diy solar

EVE 280ah 24v battery frame

B

bpal

New Member
Joined
Jan 15, 2020
Messages
40
BatteryBoxDesign.JPG
I picked up some 1/4in aluminum plate and copper bar stock this week. I should be able put this together this weekend. I had rough measurements of what I was looking for and these were in the pre-cut remnant area. Hopefully I can get the shunts mounted on the backside of the face plate as well. I'll cover the threaded bar with shrink tubing and work out some sort of cover over the top for safety.
 
Heads Up !
Ensure the shunt does not make physical contact with the metal. Some shunts have a phenolic plastic base (that's ok) but other shunts have no non-conductive bases. If it touches the metal, it will make it negative.

The aluminium is easy to work & cut, just take your time and remember to file off any sharp edges and such.
For the threaded rod. Any place like a Homedepot will stock very cheap clear tubing in assorted sizes, sold by the foot. This is actually a very nice clean solution add cheap as chips.

Cell "faces" should not really make direct contact with a metal housing, it is best to have a protective non-conductive layer between the cells & metal casings.

*Cell Tops can heat up, especially if something goes wrong. If you are covering the cells, make sure it is non-flammable or that it won't melt onto the cells, leave airspace between cell tops and any cover used.
 
Steve_S said:
Heads Up !
Ensure the shunt does not make physical contact with the metal. Some shunts have a phenolic plastic base (that's ok) but other shunts have no non-conductive bases. If it touches the metal, it will make it negative.

The aluminium is easy to work & cut, just take your time and remember to file off any sharp edges and such.
For the threaded rod. Any place like a Homedepot will stock very cheap clear tubing in assorted sizes, sold by the foot. This is actually a very nice clean solution add cheap as chips.

Cell "faces" should not really make direct contact with a metal housing, it is best to have a protective non-conductive layer between the cells & metal casings.

*Cell Tops can heat up, especially if something goes wrong. If you are covering the cells, make sure it is non-flammable or that it won't melt onto the cells, leave airspace between cell tops and any cover used.
Click to expand...


I agree. The film covering the cell casing is fairly thin, and will break when clamped sometimes. If the metal casing contacts the metal plates, you now have a direct path to that cells positive terminal. All it takes is another connection or short to create a fire, or cell destruction. I suggest some 1/16" neoprene rubber sheets. Metal rods can be covered with a piece of vinyl tubing for easy protection.

Make sure the cells are well supported from below. Even when clamped they could slip down at low SOC. Without support from below, that could cause enough movement to result in damage.
 
Thanks for the feedback

Vinyl tubing - that's a nice durable cheap method
The lower two sets of dual threaded rod is intended to support the cells from below
I'll put something between the aluminum plates and the cells
Is anything required between individual cells or is clamped directly together fine?
 
bpal said:
Is anything required between individual cells or is clamped directly together fine?
Click to expand...

If you are careful, they can be clamped directly. Otherwise some 20 thousands plastic tape works.
 
Is there any reason ABS plastic would not work as well for the ‘ends’ as aluminum?

I’m basically considering a similar design for my 8S 280Ah LiFePO4 battery though I was thinking I’d go single-row, use 3/8” or 1/2” ABS for the ends, and use 2x8 (wood) for the base (so 4 threaded rods only).
 
Sky's the limit for non conductive options. I am not sure abs is stiff enough though.
 
Luthj said:
Sky's the limit for non conductive options. I am not sure abs is stiff enough though.
Click to expand...

I would have thought non-conductive would be preferable.

The only reason I thought it might be inferior to Aluminum is that heat dissipation will be worse, but then I realized most cells only radiate heat from the edges anyway, so insulation on the end cells just makes them more similar to all the other cells...

You can get ABS up to 1” thick and if that’s still not still enough, there is always acrylic...
 
fafrd said:
I would have thought non-conductive would be preferable.

The only reason I thought it might be inferior to Aluminum is that heat dissipation will be worse, but then I realized most cells only radiate heat from the edges anyway, so insulation on the end cells just makes them more similar to all the other cells...

You can get ABS up to 1” thick and if that’s still not still enough, there is always acrylic...
Click to expand...
I would like to suggest something for those who may have not pondered it. You can buy small pieces "Off Cuts" of Plywood dirt cheap from HomeDepot, Lowes and similar. 3/4" Plywood, coated with water based Polyurathane will make solid sides bottom etc.
 
Thinking of using plastic A4 book binder sheets. They are around 1mm thick.
As long as the supplied cell buss-bar's are long enough to link terminals.
 

Attachments

  • 1599195827155.png
    1599195827155.png
    183.1 KB · Views: 24
You do NOT want thin light plastic on top of the cells, you NEED some airspace, they can get hot. Melted Plastic = Unhappy Camper.
 
The plastic sheets would be extra protection between the cells when compressed.
Going what i have read on this thread.
EVE cells only have a thin insulating film on the aluminium casing to isolate the positive of the cell .
 
I feel I ought to mention a few relative items.
1) Standard bus bars leave little to no space to allow for something between the cells.
2) I have yet to see a Teardown Video by anyone, including Will, where there is a "liner" between cells.
3) The only time I have seen any "partition" between cells, is if the casings where aluminium only without any wrap.
* if the wrap is damaged (scratched or torn for some reason) you can use electrical tape to cover it.
4) I have never seen any cells installed in metal casing which was not electrically isolated. Meaning that there is always a non-metallic isolator to prevent cell casings from making contact with the external metal surfaces.

AS WILL SUGGESTS: Using 2-Way tape between the cells prevents them moving around and keeps the entire "pack" stable & solid. Yes, it is a PITA if you have to separate the pack for any reason. This is more important in Mobile Applications like RV Camper or Boats. Prevent the cells from possible chaffing ! Even a slight bit of chaffing over time will wear though materials like aluminium and expose the contents, which of course, would be "very bad".
 
It's coming together. I was able to mount the 2 shunts as recommended for using the SBMS0. One positive terminal is beyond the first shunt and will got to the 24v bus bar. The 2nd positive terminal is beyond the 2nd shunt and will be the feed from the solar charge controller.
I placed a sheet of thin cutting board material between the aluminum plate and the battery cells. I still have to wire up the BMS to the cells.

IMG_6151.jpg
 
After 2 days of being connected to SBMS0 my cell pairs are within 6mV. SOC has not been set yet.

IMG_6165.jpg
 
  • Like
Reactions: Dzl
bpal very nice build. I am planning very similar case build and same 280ah 2p8s. Could you please make picture on the shunts from inside the box ? What shuts are you using, brand, value? what is this bank going to power?
Thank you
 
Thanks for the compliments. I went with Canadian Shunt from Newark. Mainly because they had them in stock and I had other things to order. Riedon seemed to be out of stock of most options. I went with 300A, 100mv for both shunts. I'm going to end up with 2700W in solar panels and a 3000W inverter. The SBMS0 has configuration parameters to set the resolution of the shunts independently.

1600452897397.png
I put a copper bus bar between the 2 shunts. I have some cleaning up to do on the bms sense wiring. I should be able to ultimately have the 4/0 cables below the top of the face plate as I plan to have a perforated acrylic cover over the top.

I'm also finding that at least right now I want some slack on the SBMS0 wiring as the battery bank in on the floor and its inconvenient to get down to read or adjust the BMS. I find myself pulling it out of the aluminum frame and tilting it up. Ideally I would have left the ribbon a bit longer. When this bank is mounted in the motorhome bay I'm hoping it is mostly set it and forget it and it should be fine mounted directly on the battery. I used some 4 conductor 22ga solid alarm wire to connect the shunts to the SBMS0.

IMG_6171.jpg
 
That is looking very nice pretty compact. I think I would use some kind cover on the shunts, something like U shape. I see you use 4/0 cable , do you need that big? 3000w inverter that would be 125a , how much more do you expect to draw? I will be doing similar set up on Sprinter but only 960w solar.
Thank you for picture and detailed write up.
 
I'm going to use the Victron Multiplus 24/3000/70. They recommend a 300A fuse and up to 100mm2 cable (2 x 50) depending on length . 4/0 cable is 107 mm2.

1600457843292.png

Here are the overload ratings of the Victron inverters (link). So it could handle 6000w for 1/2 second and 3900w for 30 minutes. All values would be de-rated based on increased temperatures. I'd rather oversize than undersize.
1600458840438.png
 
Thank you for this i formation. I will be using same inverter . Where do you planning install your fuses (as close as possible to the battery enclosure?)
What type fuses
 
AussieSim said:
I'm going with these 300A battery terminal fuse (unfortunately the M10 hole is oversized for EVE cells)

Click to expand...
Attaching fuse to Cell ? Well, that's new...
Usual, would be Cell to Cable, to Battery Terminal Lug, to fuse, to wire to BusBar > Devices.
Directly attaching a fuse to a cell I do not think is wise, please I urge you to reconsider that and instead make use of Case Battery Terminals. The connection at the cell you want to be as stable & "fixed" as possible, you do not want anything on a cell that can move in any way, it's an invitation for trouble.

Options:
www.summitracing.com

Painless Performance 40106 Painless Performance Remote Battery Junction Terminal Kits | Summit Racing

Find Painless Performance 40106 Painless Performance Remote Battery Junction Terminal Kits and get Free Shipping on Orders Over $99 at Summit Racing! These Painless Performance remote battery junction terminal kits are a safe and convenient way to create attaching points for the firewall or...
www.summitracing.com www.summitracing.com
www.summitracing.com

Summit Racing SUM-CSUMG1431 Summit Racing® Bulkhead Cable Connectors | Summit Racing

Find Summit Racing SUM-CSUMG1431 Summit Racing® Bulkhead Cable Connectors and get Free Shipping on Orders Over $99 at Summit Racing! These Summit® bulkhead cable connectors prevents wire from chafing on feed-through holes in the firewall. They fit a 1 1/4 in. hole and include cable connections...
www.summitracing.com www.summitracing.com
 
You must log in or register to reply here.

Similar threads

R
Rick's recommended compression containment for EVE cells (LF280K, LF304)
2
Replies
31
Views
3K
Sverige
Sverige
X
EVE 280ah problem with 1 battery only?
2
Replies
26
Views
922
GXMnow
GXMnow
SparkyJJO
Rethinking my battery box
2 3
Replies
62
Views
3K
SparkyJJO
SparkyJJO
robbob2112
I asked chatgpt to design a battery
2
Replies
29
Views
1K
robbob2112
robbob2112
hwy17
Community perceived quality: EVE 105 / 230 (Ezeal)
Replies
16
Views
879
Brett V
Brett V

diy solar

diy solar
Back
Top