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Discussion Starter #1 (Edited)
So like, Audi and vw are pushing really hard into the EV space and they're pushing really hard for FAST FAST FAST charging, 320kw i believe.

i wonder, does anyone know what geometry their batteries will be like? built in cooling and BMS'? Will they be small and modular like leaf modules? or large and not useful for conversions, like the model 3 mile-long packs.

and perhaps more importantly, could someone remove those batteries and BMS and charger system and be able to use those hyper fast electrify america chargers for their conversion project?
 

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i wonder, does anyone know what geometry their batteries will be like? built in cooling and BMS'? Will they be small and modular like leaf modules? or large and not useful for conversions, like the model 3 mile-long packs.
VW/Audi battery packs so far have been sensible, meaning that they are composed of several (not just four) similarly-sized modules (all connected to each other in series, of course), with "cold plate" thermal management. It seems unlikely that they would change approach, but I suppose that's possible.
 

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Discussion Starter #5 (Edited)
hmmmmm, do those bricks have thermal plates internally and coolant inlets/outlets? or will cooling be done by plates between the bricks?

if the cooling is totally outside the bricks on external plates that sucks, makes them much less conversion friendly since you'd need to fab plates like that depending on how you place your batteries
 

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The modules sit on cooling plates.

https://electricrevs.com/2018/04/21/audi-e-tron-vs-jaguar-i-pace-battery-pack-comparison/



Same thing for the Audi E-tron

E-Golf and Golf Gte do the same thing with smaller plates sometimes shared between modules.

On the topic of conversion friendly, you will struggle to find an application that would require that much cooling. And if you did I am sure getting a few heat plates made would not cost the end of the world, or better yet hacking up some OEM parts.
 

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hmmmmm, do those bricks have thermal plates internally and coolant inlets/outlets? or will cooling be done by plates between the bricks?
Probably not exactly either of those: only the Chevrolet Volt and Tesla designs run coolant within the module, and the "cold plate" designs (which includes all of the VW group vehicles for which I have seen a description) are under the module rather than between modules.

if the cooling is totally outside the bricks on external plates that sucks, makes them much less conversion friendly since you'd need to fab plates like that depending on how to place your batteries
Yes, that's a factor, because the cold plates are not usually separate for each module: they use one plate per layer or group of modules, to simplify construction and plumbing.
 

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Discussion Starter #8 (Edited)
On the topic of conversion friendly, you will struggle to find an application that would require that much cooling. And if you did I am sure getting a few heat plates made would not cost the end of the world, or better yet hacking up some OEM parts.
my concern is about most kinds of fast charging. Sans cooling, you limit how hard you can charge them. Especially true if potentially getting in on that 320kw charging action.

Also if you're driving hard (my build plan is high powered), i'd be worried about heat in those poor cells.

i assume making cold plates of arbitrary X/Y dimensions would be annoyingly expensive though, unless there's some really easy way to do it i'm missing

also, an interesting read that makes it seems like the way to go is cooling the battery tabs more than the surfaces https://avidtp.com/what-is-the-best-cooling-system-for-electric-vehicle-battery-packs/
 

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also, an interesting read that makes it seems like the way to go is cooling the battery tabs more than the surfaces https://avidtp.com/what-is-the-best-cooling-system-for-electric-vehicle-battery-packs/
tab-cooling makes sense for pouch cells, prismatic cells don't have the same thermal conductivity to the terminals.

BMW and VW seem to be doing fine with 10C ratings and bottom of cell cooling.

Also prismatic cells are often made of aluminium, therefor having good thermal conductivity.

Note that audi E-tron might have pouch cells inside the (same size) modules, I don't know how they handle cooling there.
 

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my concern is about most kinds of fast charging. Sans cooling, you limit how hard you can charge them. Especially true if potentially getting in on that 320kw charging action.

Also if you're driving hard (my build plan is high powered), i'd be worried about heat in those poor cells.

i assume making cold plates of arbitrary X/Y dimensions would be annoyingly expensive though, unless there's some really easy way to do it i'm missing

also, an interesting read that makes it seems like the way to go is cooling the battery tabs more than the surfaces https://avidtp.com/what-is-the-best-cooling-system-for-electric-vehicle-battery-packs/

You better have deep pockets if you want any of that 320 kw charging usually these cars run heat exchangers fed by ac compressors.

Plus let alone the CCS standard communication controllers are expensive.

Any build coming close to performance of a Tesla (model s) will cost 30K-ish just in parts.
 

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Discussion Starter #11
You better have deep pockets if you want any of that 320 kw charging usually these cars run heat exchangers fed by ac compressors.
Plus let alone the CCS standard communication controllers are expensive.
Any build coming close to performance of a Tesla (model s) will cost 30K-ish just in parts.
all true, hence just getting a wrecked taycan and getting the parts out of it.
question is if VW will do what tesla does and have incredibly strong software and remote control over supercharger access, meaning even if you have the charging system and batteries and sufficient cooling, the car it came out of is considered wrecked and thus cannot charge.

i was actually hoping to set up a system to leverage the A/C compressor to chill the coolant significantly when charging hard. Not very efficiently mind you, but at least enough.
 

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Hate to break it to you but with CCS the car exchanges alot of info with the charging station, so you can identify each vehicle.

Some vehicles even can go as far as arranging payment for you.

So the legality of taking parts from another car to make work are really difficult plus the communication will require handshaking with loads of other ECUs as this would be part of the 'security' requirements.
 

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Discussion Starter #13
my sort of hope is that while tesla is very software savvy and in some cases pretty draconian (any tesla that's ever marked as salvage is blocked from supercharging ever, even if fully restored, see RichRebuilds)....
.....volkswagen is a legacy automaker and they tend to be much more lax about this. As in, you can still charge just fine so long as everything necessary from the car is ported over.

of course, all of this is a mega questionmark until taycans start crashing and people can reverse engineer their charger systems, figure out what's needed and what isn't (the BCM and everything connected to it vs just some OK signals from some extraneous control units which can be faked), how much heat the cells generate, etc. although considering how little cooling seems to be on those etron batteries, maybe it isn't that bad

obviously any conversion would involve many module thermometers and thermal fuses to prevent runaway
 

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Volkswagen may be a legacy automaker, but the legal issues remain the same with lethal pack voltages and with dealing with the fallout of amateurs who watched three Rich Rebuilds videos and embark on an engineering effort -- hence, the lawyers call the shots on EVs.

And your butt at their charger blocking their customer (appearance that your car is not in the VW lineup, not the electronics) should, alone, get you the boot.
 
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