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Discussion Starter · #1 ·
The one area that I still need to do some more planning in is for mounting the batteries. I'll be using 10 tesla model s modules 5s2p. I want to put as many under the hood as possible, and I think I'll be able to fit all 10 there in my 2010 Ford Escape. So the question is: how do you make the battery boxes? What materials? How are you mounting them?
 

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^ More nonsense posts and it seems to be getting worse. I should volunteer as a mod and clean this crap out
I agree that this is getting worse. Based on a comment from a moderator (perhaps a couple of weeks ago), the problem may not be a lack of effort from the moderators, but rather bad tools from the forum operator for the moderators to use. Maybe contact the current moderators and ask if they would like assistance, or have technical challenges?
 

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Discussion Starter · #6 ·
I agree that this is getting worse. Based on a comment from a moderator (perhaps a couple of weeks ago), the problem may not be a lack of effort from the moderators, but rather bad tools from the forum operator for the moderators to use. Maybe contact the current moderators and ask if they would like assistance, or have technical challenges?
I've heard that there was a change a while back that gave the current moderators of this forum much less power to actually enforce anything. Something about some company went around and bought up a bunch of these forums and now isn't letting anyone properly moderate them. Not sure how accurate that was since I'm new but it seems reasonable.
 

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So the question is: how do you make the battery boxes? What materials? How are you mounting them?
It might be instructive to watch a video of a tesla pack being torn down to see how they were originally secured. I decided that sacrificing my trucks original bed was worth keeping the original Tesla battery box, as that thing is a pretty impressive piece of engineering. Man did they ever love bolts! And the whole box is made out of super-tough 1/2" thick aluminum plate, and gasketed and caulked all around. Since your batteries are not going to be riding inches from the pavement, you probably dont need anything that resilient, but some sort of a complete shell around the modules seems like it might not be a bad idea. My modules were Tesla-made, but for a short-lived electric Mercedes, and I found corroded BMS connections on every one of my modules after storing them for a year outside that enclosure. I am not sure how the storage environment factored into that, or if the model S batteries even used the same manufacturing techniques. My pack was unsealed shortly before I got it, and it had a little port on the side where desiccant packs could be stuffed in. The ones in there had a date in 2018 scribbled on the side. Anyway, hopefully my experience was a fluke, but something to think about at any rate.
 

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Something about some company went around and bought up a bunch of these forums and now isn't letting anyone properly moderate them. Not sure how accurate that was since I'm new but it seems reasonable.
Two or three parts.

Ownership changed.

Then parts of the site were crippled.

Then they were crippled again.

Then they were overhauled to a common new style of forum software (and missing parts never fixed).

It's this last stage, when we moved from the forum software we'd always used to the new system, that a lot of mod privileges vanished. I don't think we have any admins here anymore in the community. The owners/admins own hundreds of automotive forums and don't pay attention to any of them. It'll take actual months to get a reply on an issue sometimes.

I agree we need more moderators.
 

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^ More nonsense posts and it seems to be getting worse. I should volunteer as a mod and clean this crap out
You, me, anyone, but the people who'd give us that power take months to respond to questions. But, ask away, better than letting the forum be overrun. It's been particularly bot spammy today.
 

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edit: im a real person, lol

I was thinking the other day of a box to hold several modules stacked on top of each other. I imagined that the box were tight enough to hold the modules all around, notably on the sides, Then a long piece of plastic that'd fit between the edges of the modules, they'd all stack on top of each other, like rungs in a ladder while the outer box of the casing would hold it all together. The outer casing would likely be sheet aluminium. The box would either need open ends, or at least some way to connect all the coolant lines before being slid into the box.

For my initial box idea I had managed to 'fit' 4 modules on top of each other down the transmission tunnel between the crossmembers, with another 3 in the other end of the box over the front of the crossmember and upto the radiator support panel, Then i could fit another 3 modules around the side and top like a saddle. It essentially would have taken up the same weight as the old engine and gearbox, but its center of gravity would be much lower while fitting neatly between the old engine mounts on the crossmember. 10 modules in total, 240V or 120V with modules paired up
There was space for another potential 4 modules stacked 2 wide on top.
 

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Discussion Starter · #12 ·
It might be instructive to watch a video of a tesla pack being torn down to see how they were originally secured. I decided that sacrificing my trucks original bed was worth keeping the original Tesla battery box, as that thing is a pretty impressive piece of engineering. Man did they ever love bolts! And the whole box is made out of super-tough 1/2" thick aluminum plate, and gasketed and caulked all around. Since your batteries are not going to be riding inches from the pavement, you probably dont need anything that resilient, but some sort of a complete shell around the modules seems like it might not be a bad idea. My modules were Tesla-made, but for a short-lived electric Mercedes, and I found corroded BMS connections on every one of my modules after storing them for a year outside that enclosure. I am not sure how the storage environment factored into that, or if the model S batteries even used the same manufacturing techniques. My pack was unsealed shortly before I got it, and it had a little port on the side where desiccant packs could be stuffed in. The ones in there had a date in 2018 scribbled on the side. Anyway, hopefully my experience was a fluke, but something to think about at any rate.
I unfortunately don't have the space to just keep the original pack. With that being said though, I am 100% planning on having it fully sealed and watertight. I don't expect any water to come into contact with it since it'll be under the hood, but I think it's definitely worth the precaution.

What environment did you store the module in that resulted in this corrosion? It sounds like they got wet at some point. Having a desiccant pack jammed in might mean that your modules were taken from a flooded car and someone tried their best to dry out the modules to resell. Definitely something that you need to be very careful of since there's a lot of sketchy sources for modules that aren't upfront about that sort of stuff. Do the modules look the same as those from a typical Tesla pack?
 

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I am pretty certain the modules were not flooded, and the desiccant pouches went through a big screwed in plug into a little plastic cradle inside. It seems that the pack was engineered to be kept at low RH.

Once I took the modules out, they went on a pallet on the floor of my shop, covered in a sheet of plastic. The space is left open to the elements, so although the modules were 30 feet from the outdoors, if the temperature swings sometimes the whole floor in there will get slick with condensation. The BMS wires were copper, and ultrasonically welded to the aluminum bus plates - and it was those connections that failed. I am not sure if the Model S used that system, or if they are even accessible to inpect - the modules I have do not have a sealed plastic case aroud them, they are just wrapped in insulating plastic. Anyway, my modules are pretty rare, and I have not heard of anyone else that has had similar problems, so hopefully it was just a fluke.
 

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Discussion Starter · #14 ·
I was thinking the other day of a box to hold several modules stacked on top of each other. I imagined that the box were tight enough to hold the modules all around, notably on the sides, Then a long piece of plastic that'd fit between the edges of the modules, they'd all stack on top of each other, like rungs in a ladder while the outer box of the casing would hold it all together. The outer casing would likely be sheet aluminium. The box would either need open ends, or at least some way to connect all the coolant lines before being slid into the box.
Ok so I think I've got somewhat of a plan. I'll weld together a steel box made of pretty thin sheet metal that is fully watertight on 5 sides of the 6-sided rectangular box. The top will be a bolted on steel plate that has a rubber seal on the edge to keep it watertight. Then, inside the box, I'll cut up something like these PVC boards to insulate the packs from the steel box and to make "shelves" for the modules inside.

How does this sound?
 

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Discussion Starter · #15 ·
I am pretty certain the modules were not flooded, and the desiccant pouches went through a big screwed in plug into a little plastic cradle inside. It seems that the pack was engineered to be kept at low RH.

Once I took the modules out, they went on a pallet on the floor of my shop, covered in a sheet of plastic. The space is left open to the elements, so although the modules were 30 feet from the outdoors, if the temperature swings sometimes the whole floor in there will get slick with condensation. The BMS wires were copper, and ultrasonically welded to the aluminum bus plates - and it was those connections that failed. I am not sure if the Model S used that system, or if they are even accessible to inpect - the modules I have do not have a sealed plastic case aroud them, they are just wrapped in insulating plastic. Anyway, my modules are pretty rare, and I have not heard of anyone else that has had similar problems, so hopefully it was just a fluke.
Ah. The plastic casing on the other modules isn't really a solid seal though I don't think.

Maybe a small dehumidifier in the battery box isn't a bad idea even if just for peace of mind.
 

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Sounds like a plan, I'm a bit behind you so haven't made a battery box yet.
Have you tried watching some programs to see what companies are doing?
In the UK we have Vintage Voltage or you can look up Zero EV on YouTube, they explain a lot of stuff really well, may well have info on a battery box.

Sent from my moto g(8) power lite using Tapatalk
 

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Discussion Starter · #17 ·
Sounds like a plan, I'm a bit behind you so haven't made a battery box yet.
Have you tried watching some programs to see what companies are doing?
In the UK we have Vintage Voltage or you can look up Zero EV on YouTube, they explain a lot of stuff really well, may well have info on a battery box.
Ok so I did some digging on YouTube and found some videos that are exactly what I'm looking for. Here's a video in which a guy is converting a huge Ford F450 pickup with a full tesla pack of 16 modules.
 

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It might be instructive to watch a video of a tesla pack being torn down to see how they were originally secured. I decided that sacrificing my trucks original bed was worth keeping the original Tesla battery box, as that thing is a pretty impressive piece of engineering. Man did they ever love bolts! And the whole box is made out of super-tough 1/2" thick aluminum plate, and gasketed and caulked all around. Since your batteries are not going to be riding inches from the pavement, you probably dont need anything that resilient, but some sort of a complete shell around the modules seems like it might not be a bad idea. My modules were Tesla-made, but for a short-lived electric Mercedes, and I found corroded BMS connections on every one of my modules after storing them for a year outside that enclosure. I am not sure how the storage environment factored into that, or if the model S batteries even used the same manufacturing techniques. My pack was unsealed shortly before I got it, and it had a little port on the side where desiccant packs could be stuffed in. The ones in there had a date in 2018 scribbled on the side. Anyway, hopefully my experience was a fluke, but something to think about at any rate.
Worth noting a big reason for the thickness on the battery case is it is a stressed member in the car's construction. The battery is providing a lot of the Tesla's rigidity. This will go even further with their new cells in the future as the battery becomes a full structural member
 

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Discussion Starter · #19 ·
Worth noting a big reason for the thickness on the battery case is it is a stressed member in the car's construction. The battery is providing a lot of the Tesla's rigidity. This will go even further with their new cells in the future as the battery becomes a full structural member
Yes, the car's rigidity. However, cars being converted are already structurally sound and rigid without the need for more support. So it's not necessary to make the battery box a structural member of the car.
 

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Worth noting a big reason for the thickness on the battery case is it is a stressed member in the car's construction. The battery is providing a lot of the Tesla's rigidity. This will go even further with their new cells in the future as the battery becomes a full structural member
I think the trend is in the opposite direction at Tesla. A Model 3's battery case is less rigid and is more protected by vehicle structure than the Model S.

In both the Model S/X and the Model 3/Y, the battery pack hangs under the body of the car. It may contribute to rigidity as it is secured in multiple locations, but it is not even close to being a "skateboard" as it is popularly called. Look at the body of the car without any battery or other powertrain components, and it is a conventional unibody.

The electric trucks will be interesting to examine in detail when they go into production. The ones shown so far (e.g. Rivian, Hummer EV) tend to have a platform chassis with a body on top and the battery within the chassis; the battery box may be carried within the frame, or may be the frame, making the battery box structural.
 
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