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Does anyone know what type of battery thermal management is used in the MEB platform? I've had a quick Google search but havent' found anything.
 

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I was told it was forced air cooled by the VW uk marketing people at Goodwood (high ups at VW uk running the project, not minions)

Although the same guy refered to a battery capacity in terms of kilowatts so his knowledge can be taken with a pinch of salt

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What matters is how well the battery performs, not how it is cooled.

LEAF 30 does just fine with passive cooling.
Early Tesla Model S can hit thermal limits even though the pack is liquid cooled.
 

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Forced air cooling is inferior to liquid cooling surely
Direct ac like in the i3 is the best method but maintenance is a nightmare if the compressor fails and sends metal shards into the ac pipes within the battery. Relatively lightweight system too.

Watercooled is the next best, but cooling power will be reduced if you dont chill the coolant with an AC system. Also the weight of the coolant and pipework for the required cooling capacity can be considerable water is 1kg per litre.

Forced air cooling like in the imiev makes use of existing hardware (cabin AC system) to push dry, chilled air into the pack and only requires a few extra air ducts so can be very lightweight. Decent cooling power for the weight of the system.


Passive cooling is the lightest of all because there's no hardware, but the cells can get larger temperature fluctuations and cells in the middle of the pack can end up warmer than cells on the edge leading to capacity issues in the long term ( from lots of rapid charging)

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Forced air cooling is inferior to liquid cooling surely
Outlander and e-NV200 both use it without thermal issues. As with any actively cooled car, the car needs a working air con system. I see occasional reports of problems charging when the air con has failed.

Liquid cooling adds cost and complexity. It also isn't the "best" way to cool a pack. Water-Glycol mixtures don't transfer heat all that well.


The i3 uses direct expansion refrigerant cooling. Direct expansion has 3 to 4 times the heat transfer rate of a water-glycol mixture. I'm not aware of any other EV that cools the pack with R1234yf or R134a. .

Battery modules sit directly on top of the refrigerant tubes. The modules are in an aluminium case that transfers heat to the tubes. It is a relatively simple system. I wonder if the new MINI will use it.
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Discussion Starter #8
What matters is how well the battery performs, not how it is cooled.

LEAF 30 does just fine with passive cooling.
Early Tesla Model S can hit thermal limits even though the pack is liquid cooled.
The Leaf 30 might be fine with passive cooling, the Leaf 40 has all sorts of problems. Generally the data shows that the better cooled batteries capacity loss is slower and high charging rates can be sustained for longer.

Liquid cooling seems to be the gold standard, A model S Tesla works its batteries far harder than a Leaf with higher power charging and powerful motors. The Model 3 battery pack cooling is more efficient than the S and the car can be pushed harder for longer.

I wouldn't take the risk of purchasing a car without a good battery TMS.
 

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I think the concern is around longevity, not performance.
Battery chemistry, margin and BMS have a lot to do with longevity too.

When it comes down to what is "best" BMW are the clear winner. They have the best cooling system, large margins and the pack life is very good.

But is the i3 the best overall package? I don't think so. The i3 is too expensive for what it is. On top of that early ones are plagued with issues. On an i3 the pack will out live the car. A good design will have the pack last slightly longer than the car.
 

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BMW and LG have patents on direct expansion cooling. That is probably one of the reasons why no one else is using it.
 

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Forced air cooling is inferior to liquid cooling surely
Only if you wish to work the car harder then forced cooling can cope with, using air from an AC unit and you get even better cooling then simple forced air.

So if you wish to drive at 120 mph for 2hrs then charged at 250kw, clearly the best possible cooling system is needed. But for the rest of us, we just need a system that will cope the a day of UK moterway driving without limiting the speed of rapid charging.
 

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MEB packs will have liquid cooling (ID.R's air cooled battery is for racing purposes)

There is great arcticle on Jalopnik (title: The Fascinating Engineering Behind VW's Electric Car Platform of the Future) explaing a lot of the MEB tech. It even includes picture showing the location of coolant inlet/outlet.

Unfortunately the forum software automatically blocks my post if I include the actual link.
 

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Unfortunately the forum software automatically blocks my post if I include the actual link.
This -->

 

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This -->

Interesting read. I wish that it had gone into the software, service, infotainment, etc. in as much detail, but considering all of that is usually covered over - VW Group are really keeping it close to their chest. I can only speculate that they are perhaps a) hoping to be really innovative and have a clean market distinction b) they are struggling with the technology. With the Car-Net (We Connect) experiences - I worry about b) but hope for a).
 
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