# Tesla model 3 battery pack



## brian_ (Feb 7, 2017)

It seems unlikely that the modules could reasonably be broken down to smaller modules, given how Tesla constructs battery modules. The Model 3/Y modules are not the same as the Model S/X modules, but neither readily splits into sections like the many other modules of other brands which are stacks of pouch cells in frames.
Tesla Model 3: Exclusive first look at Tesla’s new battery pack architecture 
Tesla Model 3 Battery Current Collector: Radically Different Design


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## remy_martian (Feb 4, 2019)

Sadly, the supply of reasonably sized battery modules is dwindling. Brian's correct that it's impossible to resize the huge modules on a 3/Y and they do suck for integration in almost every car conversion. 

Getting the cells extracted is a chore as well - soo much goop holding them in (the older modules are also a pain for extraction - an errant chisel/screwdriver will light a cell off while it's embedded with a few hundred others...don't ask how I know this). Just not worth the trouble unless you have nothing else to do with your time.

It's going to be even more fun with their upcoming "structural" battery and extracting their 4680 coke-can cells....


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## DrGee (Aug 22, 2018)

remy_martian said:


> (the older modules are also a pain for extraction - an errant chisel/screwdriver will light a cell off while it's embedded with a few hundred others...don't ask how I know this)


😅😅😅 Don't worry Remy- I won't ask!


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## DrGee (Aug 22, 2018)

Thanks so much guys,- valuable information as usual... It's a bit disappointing, as the model 3/Y batteries are even more energy dense than the S/X. Used packs are also cheaper than the S/X ones.


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## OR-Carl (Oct 6, 2018)

How long are those modules, exactly? I have been working on an s-10 where I pulled off the bed and built a flatbed to hide my batteries under. The space in mine is roughly 5 feet by 6 feet and 9.5" deep. If I had 75kwh I would estimate a range that was nearing 200 miles.


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## DrGee (Aug 22, 2018)

OR-Carl said:


> How long are those modules, exactly? I have been working on an s-10 where I pulled off the bed and built a flatbed to hide my batteries under. The space in mine is roughly 5 feet by 6 feet and 9.5" deep. If I had 75kwh I would estimate a range that was nearing 200 miles.


From Jack Rickard's teardown; the two in the centre are 73 inches long and the two on either side of these are 67.5 inches long. They're all 11.5 inches wide and 3.5 inches thick.


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## Evbeddy (Jan 5, 2020)

Hi Guys, interesting topic. 


While these batteries are massive and mostly unsuitable for most cars Ive been thinking about either putting a model 3 battery under a van or more likely on the vans floor and building a fause floor above them. Wheel well positions may be the biggest issue with this plan depending on the van in question.


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## ephemera (Jun 25, 2020)

Out of interest, is there already a BMS available for Model 3 packs?


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## brian_ (Feb 7, 2017)

OR-Carl said:


> ... I have been working on an s-10 where I pulled off the bed and built a flatbed to hide my batteries under. The space in mine is roughly 5 feet by 6 feet and 9.5" deep.


My comment from another recent thread...


brian_ said:


> Four enormously long modules that won't fit in a vehicle being converted, unless someone wants to sacrifice the entire cargo area of a pickup truck, van, or station wagon.


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## brian_ (Feb 7, 2017)

DrGee said:


> From Jack Rickard's teardown; the two in the centre are 73 inches long and the two on either side of these are 67.5 inches long. They're all 11.5 inches wide and 3.5 inches thick.


With mounting space and housing that's something in excess of 46 inches wide (with all four side-by-side as in the Model 3 and Y)... too wide to fit between the wheel wells of compact pickups and some vans.


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## remy_martian (Feb 4, 2019)

How do you delete a posting, lol?


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## OR-Carl (Oct 6, 2018)

Part of me wants to take exception to your claim that you have to sacrafice the cargo space, Brian; but then I remember the weight! In a small truck, I am guessing that a 75kwh pack would basically max out the rear weight capacity, so even if you build it into a flatbed, you would not be able to haul anything anyway. Still, it would be pretty cool to have a little extended cab pickup that could go 200 miles on a charge.


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## DrGee (Aug 22, 2018)

This issue with the Tesla model 3 battery pack raises a question I've wanted to ask for for quite a while. Can't a whole tesla pack be fixed under the chassis similar to it's placement in production EVs? The space saving and low centre of gravity we could achieve if we did this would be fantastic. Has it ever been tried? 
I believe there's enough space in most saloons (sedans), when the exhaust, petrol tank and drive shaft are gone. Cables could be routed to either side or fed through the tunnel. Ground clearance could be improved with spacers over the springs - may not even be needed if the conversion is an SUV. Does anyone think this is feasible?


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## remy_martian (Feb 4, 2019)

You could do that. In fact, I had a 3 inch lift kit on my early 90's pickup truck that was strictly body spacers.


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## brian_ (Feb 7, 2017)

DrGee said:


> Can't a whole tesla pack be fixed under the chassis similar to it's placement in production EVs?


Sure, when the body is designed for it.



DrGee said:


> The space saving and low centre of gravity we could achieve if we did this would be fantastic


But the centre of mass of the rest of the vehicle would be raised by the amount that it would need to be lifted to accommodate the pack (and it will need to be raised). Almost anything running around on tip-toe so high that a pack will fit could be massively improved by just lowering it.



DrGee said:


> Has it ever been tried?


The closest that I have seen is Yabert's VW Westfalia, with a complete Chevrolet Bolt battery pack (mostly) under the floor. The van was already relatively tall, and the loss of ground clearance was acceptable in that case.



DrGee said:


> I believe there's enough space in most saloons (sedans), when the exhaust, petrol tank and drive shaft are gone. Cables could be routed to either side or fed through the tunnel. Ground clearance could be improved with spacers over the springs - may not even be needed if the conversion is an SUV. Does anyone think this is feasible?


But there isn't. There are lots of areas of floor or structure which are much lower than the top of the fuel tank or tunnels for exhaust or shafts. If you were shaping foam or a tank for liquid to fill all available spaces you could fit in a large volume; unfortunately, a battery pack is a rigid box, not a conformable material, so the lowest part drives the entire pack below that height.

Cars are just not made in a simplistic design that has a flat bottom with the fuel tank and muffler hanging under it so that when they are removed there is a nice available space.



DrGee said:


> Ground clearance could be improved with spacers over the springs - may not even be needed if the conversion is an SUV. Does anyone think this is feasible?


While Yabert didn't raise his VW, it is an unusual case, and even in that case he had to cut a substantial hole through the structure and the floor to accommodate the bump up at one end (under the rear seat in a Bolt) which contains small second layer of modules. Almost all production EV packs have a bump like that, either to fit more modules where more height is available (typically under the rear seat, but also under the front seat in the Leaf and some others); even Tesla packs which have a simple single layer of modules have a bump up to contain other components.

Packs have substantial thickness, so the suspension lift required to accommodate any of them is typically far too much to compensate with spring spacers.

No, I don't think this is feasible in most cases. There might be some ideal combination of a vehicle which already sits too high for no good reason other than style, a relatively flat pack, and a fortuitous alignment of the pack's bump with the space left empty by the fuel tank removal. A commercial van (such as a Ford Transit or Fiat Ducato / Ram ProMaster) with a high cargo floor and nothing under it might accommodate a pack, but the high area were it would fit is only rear of the cab area and that means it would need to be a long vehicle... and the pack which will fit will likely not be large enough for the heavy vehicle.

Most production EV designs are based on engine-driven vehicle models. The only ones which manage to fit a substantial battery pack in without major changes to the floor and structure are those which use the cargo space to carry at least a large portion of the battery, such as the Ford Focus EV:











remy_martian said:


> You could do that. In fact, I had a 3 inch lift kit on my early 90's pickup truck that was strictly body spacers.


Now, triple that lift. And of course a body lift wouldn't work to fit a full pack from a typical EV because the pack wouldn't fit between the frame rails; it would need to be a suspension lift.


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## DrGee (Aug 22, 2018)

Very relevant points Brian.
But I still think it's doable. Just humour me a bit - I might be on the verge of a "breakthrough" here...
Here's the underside of a Mercedes W220.
















What we are looking for is just 2 or 3 spare inches of depth. Notice the downward protrusion of the exhaust pipes & the transmission. If we remove all those ICE bits as well as the heat shield and the black plastic aerodynamic cowling, we'll get a couple of inches at least. 
The Tesla S/X packs have a couple of extra modules stacked at the front end, forming the bump. I think the 3/Y packs have the integrated charger & dc/dc parts in the packs' bump. I would suggest removing everything in the bump and putting them under the hood. Then custom reseal the pack. The thickness of the tesla pack without the bump would be about 4 -5 inches. if you've got even just 2 inches from stripping the ICE components from the car, you lose 3 inches of ground clearance a the most. 2-inch spacers over our springs and we in business yes? Merry Christmas everyone!


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## brian_ (Feb 7, 2017)

DrGee said:


> ...
> Here's the underside of a Mercedes W220.
> View attachment 121180
> 
> ...


Those places where the lift are supporting the car are structure - take off the aero covers and you gain perhaps a few millimetres, not inches. I also suggest measuring a Tesla pack... both the Model S/X modules and the Model 3/Y modules alone are 3.5" thick, so the pack will likely be far more than 4 inches. Then look at the clearance under the middle and take more than three inches away - I expect that you'll grind the battery pack into speed bumps.

Module design note: Although the Model 3/Y use cells which are longer (taller) than the Model S/X by 5 mm, the newer design interleaves both bus plates on the same side of the module, saving enough height to allow the modules to be the same overall height.​
Starting with a crossover/SUV style of vehicle and giving up the extra ground clearance of that style has more potential, but I'm sure that it's still not going to work well without radical floor surgery.


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## remy_martian (Feb 4, 2019)

brian_ said:


> Sure, when the body is designed for it.
> 
> Now, triple that lift. And of course a body lift wouldn't work to fit a full pack from a typical EV because the pack wouldn't fit between the frame rails; it would need to be a suspension lift.


It WOULD fit the modules if they were in a custom battery case that had the body mounts incorporated as hardpoints. And, no, it would not have to go between the rails, but on them.


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## DrGee (Aug 22, 2018)

brian_ said:


> Those places where the lift are supporting the car are structure - take off the aero covers and you gain perhaps a few millimetres, not inches. I also suggest measuring a Tesla pack... both the Model S/X modules and the Model 3/Y modules alone are 3.5" thick, so the pack will likely be far more than 4 inches. Then look at the clearance under the middle and take more than three inches away - I expect that you'll grind the battery pack into speed bumps.
> 
> Starting with a crossover/SUV style of vehicle and giving up the extra ground clearance of that style has more potential, but I'm sure that it's still not going to work well without radical floor surgery.


I used to own a w220, but it was many years ago. I wish I'd spent more time under it back then... I'll have to check under one now, if I can get one to look at - and take a tape measure with me. 
I've seriously considered using a Ford Expedition as a vehicle to convert. It comes with 9" of clearance. Is it an even crazier idea? It weighs 2.6 tonnes and has the cd of a brick... I like the idea though 😊


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## remy_martian (Feb 4, 2019)

I have an F-450 in the queue, so brick no longer matters as much if it's for hauling stuff. The rolling resistance dominates in that situation, IMO. 

Think about it...a half ton truck has the same CD as a two ton, but the two ton's rolling resistance at least doubled, if not tripled when towing. 

This is where the over the road "trains", where they hook up a half dozen trailers to one semi, in Australia are brilliant (until you jackknife it, lol).


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## DrGee (Aug 22, 2018)

Yeah, 'till you Jack knife it!... I don't even want think about what that would look like! 
Back to converting full size SUVs though - I'll have to do the maths on a rig the size of an Expedition. That huge frontal area.. But the idea is growing on me. There's just so much room for batteries, even if I decide to use a 62kwh Leaf pack.


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## Evbeddy (Jan 5, 2020)

Merry Christmas everyone.

Hopefully by the end of January I will have the vehicle Im looking to covert. Its a van and my preference at the moment is to stick a model 3 battery under it. Once I get it I will take some measurements and post some pics and see if its really feasible. If not I will have to think up a plan B......


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## DrGee (Aug 22, 2018)

Evbeddy said:


> Merry Christmas everyone.
> 
> Hopefully by the end of January I will have the vehicle Im looking to covert. Its a van and my preference at the moment is to stick a model 3 battery under it. Once I get it I will take some measurements and post some pics and see if its really feasible. If not I will have to think up a plan B......


Eagerly waiting to see those pix & measurements..


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## remy_martian (Feb 4, 2019)

DrGee said:


> Yeah, 'till you Jack knife it!... I don't even want think about what that would look like!
> Back to converting full size SUVs though - I'll have to do the maths on a rig the size of an Expedition. That huge frontal area.. But the idea is growing on me. There's just so much room for batteries, even if I decide to use a 62kwh Leaf pack.


62kWh might get you to the corner grocery store. I'm planning 3x-4x that in the '450. Got truck, got cells, but 2 cars to do ahead of it. Hobbies...


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## DrGee (Aug 22, 2018)

Woah! 3-4 x 62kwh? You mean like 200 kwh? Where did you get them? Ebay prices are like 16k for an 80 Kwh pack - I wish I knew a cheaper source.


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## remy_martian (Feb 4, 2019)

Nobody said they were cheap 😬


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## brian_ (Feb 7, 2017)

remy_martian said:


> 62kWh might get you to the corner grocery store. I'm planning 3x-4x that in the '450...





DrGee said:


> Woah! 3-4 x 62kwh? You mean like 200 kwh?


The coming electric pickups - which are all just light-duty stuff - have at least 100 kWh of battery and some appear to have over 200 kWh at least in the top version. That makes sense to me, as both aero drag and rolling drag are far greater (especially when loaded or pulling a trailer) than the existing production EVs which come with close to 100 kWh.

A full-sized urban transit bus is admittedly bigger and heavier than an F-450 (perhaps twice the loaded weight of an F-450 towing a trailer), but for comparison those buses in electric form carry a few hundred kilowatt-hours of battery capacity - the Proterra ZX5 has from 220 kWh to 660 kWh, depending on the desired range and the nearest city to me just bought 40 of them with the 660 kWh required to run a full shift of a few hundred kilometres.


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## remy_martian (Feb 4, 2019)

Good analysis, Brian.

Transit bus, laden, is 20-50% heavier than a F-450 towing a loaded 16k trailer (total weight 25,000-ish lb, or ~5-6 Teslas in rolling resistance on a good day. This is why I said the aero gets less significance). 

I'm _guessing_ around 1.5k-2kWh/mile...which works out to about 10MPGe at $3/gallon diesel and $0.15/kWh utility rates. 

Do the math and public charging stations make zero sense if the truck is loaded round trip. Running empty on the return gets a net of 15MPGe, though. But, then you are paying the driver for an empty truck/trailer.

It all changes if you own solar/wind to do the charging, though.

This is pure economics. The whole clean air thing means even paying a slight premium is ok.


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## brian_ (Feb 7, 2017)

Proterra says 1.6 to 2.1 kWh/mile for the smallest battery (lightest) to 1.8 to 2.7 kWh/mile for the heaviest (largest battery) versions of its 40-foot bus... so yes, that's roughly the energy requirement we're talking about.


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## Evbeddy (Jan 5, 2020)

Heres a project I found on open inverter forum that I thought was topical for this discussion. It involves a guy trying to put a model 3 battery under a 2006 BMW E61 wagon. Will be interesting how he gets on.
Enjoy.




BMW E61 2006 LDU-sport Model 3 battery - openinverter forum


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## DrGee (Aug 22, 2018)

This is just brilliant! He's gone quite far with this project too. I think Matija, who did a great conversion on a 5 Series is following this too. 
I'm really eager to see if he can fit the battery pack under the floor as planned.


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## 266917 (May 4, 2020)

I wish I had a module to test fit for my truck project. With them being 4" wide, you could mount along the inside of the bed and only lose 8" of width if you ran a module up either side. (It'd take two get the 144V nominal I need.) I don't expect there's quite enough height on the bedsides to fit both modules on the same side. Filling the bed with batteries would defeat the purpose of the truck, but I'd give up 4" on each side to triple my capacity. 

I'm just not willing to gamble a couple of grand on a cell to try it out, unless I'm pretty sure it'll work.


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## brian_ (Feb 7, 2017)

Richter12x2 said:


> I wish I had a module to test fit for my truck project. With them being 4" wide, you could mount along the inside of the bed and only lose 8" of width if you ran a module up either side. (It'd take two get the 144V nominal I need.) I don't expect there's quite enough height on the bedsides to fit both modules on the same side. Filling the bed with batteries would defeat the purpose of the truck, but I'd give up 4" on each side to triple my capacity.


They're not designed to be mounted on edge but presumably a suitable supporting bracket that would work. Now the concerns...


DrGee said:


> From Jack Rickard's teardown; the two in the centre are 73 inches long and the two on either side of these are 67.5 inches long. They're all 11.5 inches wide and 3.5 inches thick.



The truck needs a 5.5' bed to use the smaller (23S) modules, and a 6.5' box to use the larger (25S) modules
I agree - bed walls keep getting taller, but with brackets and housings two are not going to stack up on each side.
While they are only 3.5" thick, by the time you add structure and housing including a wall on the interior side sufficient to protect them from damage by cargo it will be more than 4" thick.


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## Duncan (Dec 8, 2008)

DrGee said:


> From Jack Rickard's teardown; the two in the centre are 73 inches long and the two on either side of these are 67.5 inches long. They're all 11.5 inches wide and 3.5 inches thick.


That is not very large - if you were willing to throw away the front seats - replace with narrower (competition seats) and do some cutting you should be able to put three or even four modules down the centerline of the car
My Subaru has a center console that is 10 inches wide and 16 inches tall - if you made that a bit wider a bit higher and the full length from the footwell to the rear seat back you could get four modules in that space

Other cars will not have that center tunnel - but they will still have the space there if you move the seats apart by a small amount


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## 266917 (May 4, 2020)

brian_ said:


> They're not designed to be mounted on edge but presumably a suitable supporting bracket that would work. Now the concerns...
> 
> 
> The truck needs a 5.5' bed to use the smaller (23S) modules, and a 6.5' box to use the larger (25S) modules
> ...


If you keep it to just an interior and top wall instead of all the way around, and don't use 1/4" thick plate, then you should still be in that 4" area, I'd think. Still not bad for a truck that's probably going to haul dirt and mulch more often than chrome bumpers. Maybe keep a piece of wood in the back if I need to carry plywood sheets or drywall, so that it can sit over the top of the batteries and still be supported in the middle.

But again, not likely to do either unless or until I get a stonking deal on a pair. $4k is a lot to gamble on something that may not work. Maybe when I do the Packard I'll look at them again. They can probably all fit in the trunk sideways.


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## Fredd90 (Feb 20, 2021)

Hello my first post at this forum 

I have just mounted a model 3 battery to my bmw e61, 5 series 2007
It was a bit of a job to get the battery in place, had to raise the floor about 100mm from the thresholds.
It affects the original internal floor level by about 10mm.

Also mounted a tesla p85 engine with complete subframe.


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