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Heyoo,

Does any one by chance know the dimensions of the battery modules inside the Chevy Bolt pack?

Im hoping to find the individual module size, and the paired size. I know they are 2 bolted together with a total of 5 units for 10 modules. Any info would be sweet!

Mark
 

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Those dimensions are presumably for the bare modules. They are clamped down to thermal management plates ("chill plates", although they are also used for heating, carrying circulating coolant), adding height. The 8S modules are proportionately shorter. Both module sizes are placed end-to-end (so about 38" long using jasonwray's measurement) in the pack. The pack has four pairs of 10S modules, with a pair of 8S modules sitting above the rear-most of the 10S pairs (so the pack bumps up under the Bolt's rear seat).
 

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I've measured a single module as:
13.6" not including terminals, 14.5" with terminals x 19.375" x 4.3" not including mounting ears, 4.55" including mounting ears. This ignores the plastic lifting eye molded into the plastic where the modules were joined (it sticks up another 0.5").

So in short if you cut off the lifting eye, and grind off the mounting ears the module is 4.3" and they could be stacked easily.

If you intend to tap into the BMS connectors the mating connector is:
https://www.digikey.ca/en/products/detail/molex/0347910080/3202548
and pins:
https://www.digikey.ca/en/products/.../3178487?s=N4IgTCBcDaIKwDYAMSwGYkBYwEYQF0BfIA

Both connectors are populated from the left looking at the back, 6 pins on the terminal side, and 5 pins on the non-terminal side of the battery.
 

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I've measured a single module as:
13.6" not including terminals, 14.5" with terminals x 19.375" x 4.3" not including mounting ears, 4.55" including mounting ears. This ignores the plastic lifting eye molded into the plastic where the modules were joined (it sticks up another 0.5").
Excellent details :)

So in short if you cut off the lifting eye, and grind off the mounting ears the module is 4.3" and they could be stacked easily.
These modules are intended to be cooled (and warmed) by contact with a "chill plate" on one of the large faces. It seems like a bad idea to directly stack them, and if stacking them with a chill plate the plate would of course add to the height.

It would be possible to sandwich a chill plate between two modules, so the same two-sided plate provides thermal management to both modules. This is apparently the configuration used by Rivian in their proposed pickup truck.
 

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Excellent details :)


These modules are intended to be cooled (and warmed) by contact with a "chill plate" on one of the large faces. It seems like a bad idea to directly stack them, and if stacking them with a chill plate the plate would of course add to the height.

It would be possible to sandwich a chill plate between two modules, so the same two-sided plate provides thermal management to both modules. This is apparently the configuration used by Rivian in their proposed pickup truck.
Yes and yes, simple yet to be tested idea attached. The plate between the module would be roughly 0.1-0.125" plus two 0.02" thermal pads.
This definitely isn't tesla level cooling, however the difference is time, will a system like this get heat out (or in) quick enough.
 

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Yes and yes, simple yet to be tested idea attached. The plate between the module would be roughly 0.1-0.125" plus two 0.02" thermal pads.
This definitely isn't tesla level cooling, however the difference is time, will a system like this get heat out (or in) quick enough.
For clarification, it appears that you are planning to unstack the cells and frames of the Bolt module, remove and replace each existing thermal transfer plate with a new plate (or just add the new plate, making that stack longer), stack blocks (presumably of aluminum) between tabs of the new plates, and cool the stack of blocks with a single loop of tubing carrying coolant. That makes some sense, but seems like a lot of work and a lot less effective than just clamping the module to a chill plate which would be no thicker than the new tabs and blocks.
 

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For clarification, it appears that you are planning to unstack the cells and frames of the Bolt module, remove and replace each existing thermal transfer plate with a new plate (or just add the new plate, making that stack longer), stack blocks (presumably of aluminum) between tabs of the new plates, and cool the stack of blocks with a single loop of tubing carrying coolant. That makes some sense, but seems like a lot of work and a lot less effective than just clamping the module to a chill plate which would be no thicker than the new tabs and blocks.
These are the bolt modules as they come, no major modifications. (other than removing the lifting eye, and possibly grinding off the mounting feet if required. I modeled it as a rectangle for simplicity without the pressed steel mounting plate on the one end.

There is no added plate between the cells, it's just a flat aluminium plate to bring the heat out/in to the cooling/heating tube located between the terminals. This keeps the outer dimensions as compact as possible while allowing liquid heating and cooling.

If there was a cost effective chill plate of the correct size, it must cover the total width, and a fair amount of the height, I'd happily use that, but it looks like it's going to be a custom item. It has to be between 17.25" and 19" wide by 7-8" minimum to 10.75" ideal. For my application I'd like the coolant inlet/outlet to be on the longer dimension closer to the centre so it doesn't come near the battery terminals.

For clarity, the image depicts 6 complete 10S LG/Chevy Bolt modules with cooling between them (60S or about 36kwh). The individual parts are shown unassembled on the left.
 

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Seems like a whole lot of trouble for zero net gain.

Why don't you leave the thick aluminum cans around the cells and simply clamp them to your chiller blocks?
 

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That will cool/heat a few of the cells really well, the centre, and outside cells don't touch the chill plate.

This was my point made previously, you need a very specific size to properly cover all of the cells. A thermal pad won't distribute the heating/cooling, you would need a heat spreader.

Give me a total for a proper heat spreader, two of those chill plates and all the required thermal pads...

I'm using 10 modules in my car.

I predict very expensive...
 

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Seems like a whole lot of trouble for zero net gain.

Why don't you leave the thick aluminum cans around the cells and simply clamp them to your chiller blocks?
Looks like I'll have to do a new rendering to make things clear. The WHOLE module is represented IE there are 6 complete 10S modules linked together. Plus the parts laid out individually on the left.

This isn't some overcomplicated modification to a single module.
 

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oh...I thought it was a cell block (I'm sure Brian has a standard term) of 2 cells in their plastic carrier the way you drew it
 

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For clarity, the image depicts 6 complete 10S LG/Chevy Bolt modules with cooling between them (60S or about 36kwh). The individual parts are shown unassembled on the left.
Ah... I incorrectly assumed that you were showing the cells within one module, rather than an enormous 14.5" x 19.375" x 27" block of six modules.

In that case, the design is similar to that used by snowdog in his Electric Supercar for the modules mounted in the front of the car. He also has normal chill plates which were custom made for the the modules which are mounted behind the driver. Perhaps snowdog can point you to which point in which YouTube video those cooling systems is shown.

Thermal conduction by the thin plate to a small block on one edge seems unlikely to me to provide significant cooling, or to help even out temperatures across modules very well. It might just cause one end of the middle cells of each module to run cooler than the others, increasing imbalance.
 

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oh...I thought it was a cell block (I'm sure Brian has a standard term) of 2 cells in their plastic carrier the way you drew it
So did I.

For those not following what remy and I are saying, these modules are stacks of cells in plastic frames (or carrier), with one frame per two cells, and a heat conduction plate between each pair of frames (so each cell is against a plate on one side). They don't form a usable module until there are special end frames added and the stack is bolted together, the cell tabs ultrasonically welded together, and terminals are added.
 

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That's a nice part. It is Aavid 416201U00000G sold by Mouser in Canada. That size is a couple hundred Canadian dollars, and is smaller in both dimensions that a Bolt module; it is presumably cheaper in the U.S., although the first U.S. source I found (Allied) charges about the same (US$142). There are other distributors: at DigiKey the same item is CA$147.38, so shopping around would pay.

How do they flatten the tubes?
The description says it has
a continuous tube that is press fitted into an extruded aluminum plate
From the datasheet, it appears that the round tubes are bent to the serpentine shape, placed in the plate grooves (with the top side of the tube protruding because the groove is wider but shallower than the tube diameter) then pressed down with a flat plate to deform into a "D" shape. This embeds the tube without having to build a complete "sandwich" with two plates, presses the tube and plate into tight contact, and exposes the tube directly to the component to be chilled (which is normally another metal structure in the case of the electronics that they are building for).

The manufacturer is the Aavid Thermal Division of Boyd. Their Hi-Contact™ Tube Liquid Cold Plate product page lists various sizes, and the go quite large, but of course none match the length and width of the Bolt modules. Figure 4 of the datasheet (as posted by Mouser) shows that custom sizes are available, and what the parameters are; they can go quite a bit larger than a Bolt module, but custom construction is probably not reasonable for a small quantity. I suppose anyone with a mill could make suitable plates and anyone with a large enough press could fit the tubes into a plate; it might even be possible to use a roller press.
 

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That will cool/heat a few of the cells really well, the centre, and outside cells don't touch the chill plate.

This was my point made previously, you need a very specific size to properly cover all of the cells.
Even if a chill plate like this is only half the width of the modules, and about the same length, it could cool (or heat) far more evenly than the proposed design with a plate sized to match the module face and a cooling block on just one small part of one edge.

The stock plates which are between each pair of cells have the same issue, because they are cooled on only one edge; however, they are cooled along the entire edge, and they fold over the long side of the cell to provide substantial area for contact with the chill plate.
 
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