Material as insulator between 280ah EVE cells

sshibly

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I received my EVE cells,
7 cells at 3.30 v
1 cell at 3.29 v

1 cell had a deep dimple damage, I contacted Xuba, no response yet.

I am going to tape the cells in a 4s1p config,

What can I use as insulator in between the cells?

I have some thin cutting boards from the dollar store, but what SHOULD I use as proper insulation between cells?
 

snoobler

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None. You should compress/constrain them per the datasheet requirements and the exhaustive discussion thereof.
 

sshibly

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I agree on compressing and not using something in between the cells, but the blue plastic is so thin and i am going to use mine in my boat/van and lots of vibration and shock,

Critic the option below please in terms of effectiveness of insulation and moisture

1. add another wrap on top of current wrap
2. add a hard resin/epoxy/synthetic paper thin layer in between cells
3. Add a shock absorbing layer - bottom - amazon has neoprene rubber sheets (dunno how shock absorbing they are.
 

Woodworks

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My thought is formica or any plastic laminate. Westinghouse invented Formica in the 20's as a replacement for mica insulation used in electric motors and commutators. Check your local cabinet shop for scraps, I know I throw away enough to do a 8 cell pack every time I make a countertop. If you don't want to use formica ( plastic laminate) you can also use Nomex paper. It is used for making slot insulators in electric motors and armatures, it would be a pricier option
 

DThames

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Is the case connected to one of the terminals? If not, no electrical insulation is needed. But for high vibration, you might want a layer of something in between. But if you clamp them, vibrations should not be moving them relative to each other.
 

Rocketman

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My batteries will be in an RV. I will have an RV tank heater underneath the batteries. Because the heater is sticky on the battery side (designed to stick to the bottom of a holding tank) I wanted something that was electrically nonconductive and also thermally conductive. Looked those properties up in google and someone suggested mica - like what is in microwaves. Found some on google - so I will be trying that - it also may work well between batteries if your design calls for that.
 

Woodworks

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The only issue with Mica is it is basically
Glass. It was also used for windows in the
Old style upright wood stoves. I think aluminum might be a better option
 

Mike Jordan

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My thought is formica or any plastic laminate. Westinghouse invented Formica in the 20's as a replacement for mica insulation used in electric motors and commutators. Check your local cabinet shop for scraps, I know I throw away enough to do a 8 cell pack every time I make a countertop. If you don't want to use formica ( plastic laminate) you can also use Nomex paper. It is used for making slot insulators in electric motors and armatures, it would be a pricier option
If any plastic laminate would work, why wouldn't a non-laminate plastic like the thin HDPE the OP suggested work?
 

Woodworks

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It will work. You could use almost any non-conductive material that doesn't
Compress. After 25 years working with laminate I have plenty left over from jobs.
You could also use 1/32" plexiglass from home Depot.
 

ArthurEld

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A small pair of women's panties would probably work as an insulator.

I am not using anything between my cells either. I have a couple nicks in the plastic and I should cover those but they don't line up with each other anyway.
 
Last edited:

Woodworks

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If the pack is compressed properly I don't think so either.
I was just responding to a question about what could be used for an insulator if that's how you want
to build your pack. For a marine application I think it's cheap insurance, adding an extra layer of safety
never hurts. Laminate is .032 there is enough play in my 280 Eve cells to add laminate between cells using stock bus bars but like most people I will be making mine so that's not an issue.
 

WA5IDX

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While I agree that in stationary installations, additional insulation between cells is likely not needed, in mobile environments additional "insurance" might be warranted. Movement between cells even if a very small amount, could result in damage to the plastic cell covering (albeit might take considerable time). Even in a "fixture", there is a need for damping vibrational impact on the cell pack. Given the expansion between cells and the variable nature of the compression ( see all the threads), & the total mass of the cell pack, it would seem that some type of insulator/vibration would not necessarily lead to issues especially since it would allow individual cell movement to some degree if needed. The buss bar issue is there which is why many are using braided ,etc. type bars anyway.
 

HRTKD

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In ten years, when I replace my cells, I'll let you know how much wear there is on the OEM material between the cells.

I don't think the entire cell expands. I bet the edges of the cell are not where expansion takes place. It's the center of the long sides where expansion may take place.
 

sshibly

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It's the same guy who started this thread. I figured he needed a use for them
We have a winner boyz,
Meets all the criteria, synthetic, breathable, light and give the li cells quite the look,

I am going to try them out, I mean on the li cells and post my finding, this is serious scientific studies hu know.
 

blutow

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It seems like limiting movement between cells would prevent any wear of the plastic. What about using some double back tape between cells? Vhb would work well and it’s thin, but it’s basically permanent.
 
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