3D printed battery bracket for EVE 280-320AH prismatic cells

[justgary]

Nope that's wrong. Each cell expands 1mm or 4mm for all. 1/4" foam needs to be compressed 15-25% to get initial 11psi force. The window to maintain 11psi is small so more sheets you add in series the better (up to a point of diminishing returns). Pull up a datasheet for your foam and see for yourself. If you gonna do compression at least do it right.

Adding foam layers is the same as adding springs in series. You will get less force for the same deflection. Not only did I look up the datasheet, I did the experiment as well. I still recommend one sheet of 1/4" foam for each four cells.

https://diysolarforum.com/threads/a...thread-this-time-about-foam.16537/post-530262

 

[Aridom82]

How about this? I've removed the cutouts, and also reduced the edge by 2mm, so they won't come in contact before the cell, but still use the dowels to keep everything locked together. The thickness of the back is 2mm right now which I think might be kind of thick in this case, so I could reduce it to 1mm (as it comes in contact back-to-back anyway, and one the ends you'd want something not plastic to give uniform pressure over the side of the battery I would assume). Thoughts?

I am a 3d printing guy myself and i used 3d printed press plates reinforced with steel bars.
To hold the compression over the expansion range of the cells i used 4 springs, each one can hold up to 100kg
Also i used a bunch of 3d printed fixtures to hold all the components to the threaded rod.

 

[Anx2k]

I am a 3d printing guy myself and i used 3d printed press plates reinforced with steel bars.
To hold the compression over the expansion range of the cells i used 4 springs, each one can hold up to 100kg
Also i used a bunch of 3d printed fixtures to hold all the components to the threaded rod.
View attachment 250204

That looks pretty awesome - the springs are a cool idea to maintain tension, and capturing those steel bars in the 3D print is a great way to keep things aligned.

 

[chicagoandy]

View attachment 250063

How about this? I've removed the cutouts, and also reduced the edge by 2mm, so they won't come in contact before the cell, but still use the dowels to keep everything locked together. The thickness of the back is 2mm right now which I think might be kind of thick in this case, so I could reduce it to 1mm (as it comes in contact back-to-back anyway, and one the ends you'd want something not plastic to give uniform pressure over the side of the battery I would assume). Thoughts?

Very nice, have you published that STL?

 

[ragnakore]

And here's it in the real world:
View attachment 249636View attachment 249637

Ducan offered similar plastic brackets.
But cost and feature wise, I went for a metal Battery Box with complete features (compression, bms mounting holes, circuit breaker cutouts, bms comms cutouts etc...)

These plastic brackets are too DIY, I can't use it for a $25K customer solar project.

 

[Anx2k]

Very nice, have you published that STL?

Not yet, I'll do it this weekend - just wanted a bit more gap between the left/right portion of the cell, just to make sure the plastic isn't getting jammed, etc. I'm printing a couple right now just to check fitment, but once that's done I'll upload it and a link.

 

[AntronX]

What kind of 3D printer is that?

 

[Anx2k]

What kind of 3D printer is that?

Bambu Labs X1C, using the Wham Bam textured PEI plate, which I love - holds great without glue and releases when cold no issues - plus the finish is almost impossible to tell it’s 3D printed (except the top and sides, obviously, although at 0.20 layer height the sides aren’t bad).

If you’re looking for a printer, I can’t recommend Bambu Labs enough - we have 8 of them printing all the time, and only had 3 failures in the past year. Compared to the Prusa I3Mk3’s we had (8 of them also), at least one was basically down every week, year round. Really a shame because I like the whole Prusa concept, and before Bambu they were the best, but it’s no comparison now.

 

[Anx2k]

Here's the link to the compressed STL:

https://makerworld.com/en/models/738700

 

[Hungfish]

I am a 3d printing guy myself and i used 3d printed press plates reinforced with steel bars.
To hold the compression over the expansion range of the cells i used 4 springs, each one can hold up to 100kg
Also i used a bunch of 3d printed fixtures to hold all the components to the threaded rod.
View attachment 250204

nice compression design.
did you release the STL file ?
thank you

 

[PowerMan]

Ducan offered similar plastic brackets.
But cost and feature wise, I went for a metal Battery Box with complete features (compression, bms mounting holes, circuit breaker cutouts, bms comms cutouts etc...)

These plastic brackets are too DIY, I can't use it for a $25K customer solar project.

Which metal box did you go with? Are you happy with it?