Placing Weight On Cylindrical LifePo4 32650 Batteries

Greetings community,

I am building one of the DIY battery supplies in a toolbox. I am using the 100ah 3.2v packs wired in 4S from Battery Hookup that are currently not available anymore. They use 32650 LifePo4 cells shrink-wrapped (see photos). I am sitting them secured laying flat on the bottom of the toolbox. This is the long axis of the battery sitting vertically for strength.

Do people think it's okay to lay very thin plywood straight on top of the batteries and then have the weight of the other equipment sitting on that board? This would be the inverter, primarily, but some other weight that would add up (not sure where the solar controller will be yet). Due to the nature of my toolbox it will be hard to lay these battery packs flat and build a support frame around the batteries that the inverter can sit on. So I would like to protect the battery with foam or some padding and lay the thin board over as I am suggesting.

Is it bad to have a little bit of weight sitting consistently over time directly on the battery packs? I would prefer to provide support over the battery but cannot easily make it work the way I want in this toolbox.

Thanks for any opinions!

Wood can absorb moisture and become conductive. Also it is flammable...
As for strength, I'd guess this is a bad plan as the connections could make pinch points to and short the cells.

Hmmm, I can just use these rigid PVC sheets I have and figure out how to support them slightly above the battery packs. Isn't almost everything flammable? Yes, I know wood is more flammable. Lots of people use wood in their DIY boxes for better or worse, but since I also have this PVC material I was saving, I can use it now.

Thanks for the reply Supervstech ... further research reveals that wood is so frequently used in DIY boxes that a lot of us must be idiots, or the risk is just very low. If I use wood I will keep it spaced and be thoughtful. The strength of the battery was my primary concern, and I will definitely not put any significant weight on the batteries.

futureproof said:

Thanks for the reply Supervstech ... further research reveals that wood is so frequently used in DIY boxes that a lot of us must be idiots, or the risk is just very low. If I use wood I will keep it spaced and be thoughtful. The strength of the battery was my primary concern, and I will definitely not put any significant weight on the batteries.

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Oh, I wasn’t saying wood is a bad choice, more that it shouldn’t be in direct contact with cell terminals. Especially if weight is placed on them.

Supervstech said:

Oh, I wasn’t saying wood is a bad choice, more that it shouldn’t be in direct contact with cell terminals. Especially if weight is placed on them.

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I believe the cells are fully shrink wrapped so wood isn’t the only insulator.


As to the OP, I believe battery hookup discontinued those packs due to the capacity not holding up very long. Do some searches here others have reported issues.

If you are laying 4 packs flat at the bottom of the tool box couldnt you cut some sort of posts so the plywood is supported by the posts vs the cells?

740GLE said:

I believe the cells are fully shrink wrapped so wood isn’t the only insulator.


As to the OP, I believe battery hookup discontinued those packs due to the capacity not holding up very long. Do some searches here others have reported issues.

If you are laying 4 packs flat at the bottom of the tool box couldnt you cut some sort of posts so the plywood is supported by the posts vs the cells?

Click to expand...

I had not yet come across those reports of those particular 12v battery packs. So they are not living up to expected cycles? Or the capacity is lower than the rated 100ah? I'll search...

The 4 x wood posts with a plywood cover method was going to be my first plan, but when the packs are laying flat, they sit so close to the edge of the box I bought I couldn't get the posts in. I may be able to keep working with the layout and figure it out. Or if I am really not happy, I could ditch this box for another.

How much movement will this tool box see?

How secure is the plywood side to side?

I’d place some foam tape on the cells top and bottom, double sided would prob not be needed if the plywood and cells are secure. That way it provides some more protection of that shrink wrap.

Also i wouldn’t be that concerned about the weight of the plywood or the BMS, pretty minimal.

I Use,
1.High temp Hot Glue. keeps terminas from moving.
2. Barley paper. Insulator.
3. Adhesive black rubber 1 mm. Impact resistant
4. Shrink wrap blue. Help with mechanical Strengh and a bit fire retardant.

The box may not see significant movement or drive time, but in case that changes I will be securing fairly well and minimizing abrasion or rub points. I like the foam tape idea too. The weight I would be worried about directly on the batteries is the inverter, but I am committed to framing something for the inverter to stand off the batteries. Also like the adhesive black rubber idea. Thanks all! This is on hold for now due life complications, but back to it soon hopefully!

I just wanted to add I've been using 16 of these 32650 premade packs for over two years as a 24v system and they've worked well. I haven't checked the capacity lately but haven't felt the need. My guess is batteryhookup stopped selling them because they sold out, but I'll maybe have to read up about others having trouble.