Route AC over battery

[DougWantsALeaf]

Does anyone on this board actually know what or how the ENV200 forced air cools its electronics and/or battery?

It is just cool air over the battery case? or something more integrated?

[goldbrick]

https://www.greencarreports.com/news/10 ... nditioning

This article says that the AC just routes cold air over the battery but I seem to remember mux saying that the only entrance into the battery pack were 2 sealed coolant lines. Ie, there is no air blown into the pack, but there is an evaporator and/or condensor inside the battery pack and refrigerant is routed into the pack instead where it either evaporates or is compressed to create a heat pump. That and a very small fan seem to be enough to make a big difference in battery life on the NV-2000. Too bad Nissan didn't put this in the Leaf.

[alozzy]

According to this article, the "active" cooling in the e-NV200 is only used for charging:

https://insideevs.com/news/322347/heres ... tery-pack/

However, this cooling system isn't designed to cool the cells, but rather to "ensure optimum charging conditions at all times." More specifically, Nissan says that e-NV200 incorporates a "bespoke cooling pack that operates automatically during quick charging."

Then later in the article:

It does not direct air at the cells/pouches, but rather towards the various electronics/controllers within the pack.

[Oilpan4]

Sounds like some one just needs to cut some holes in a leaf battery, run some A/C to it and find out.

Too bad all those really smart engineers at Nissan didn't see this obvious solution.

The engineers saw the obvious need for cooling. The bean counters shot it down.
Management and bean counters lay the basic design for cars, the engineers get stuck trying to build the car with what the people who have MBAs and accounting degrees say they can use and spend.

When engineers run a company like tesla you get a cool car that's fast and lasts a long time with shaky and questionable financial fundamentals.

[Oilpan4]

Does anyone on this board actually know what or how the ENV200 forced air cools its electronics and/or battery?

It is just cool air over the battery case? or something more integrated?

Yeah Mux posted a picture or a link to a picture that showed a cutaway inside the nv200 battery.
The nv200 had a horizontal heat exchanger on the back hump of the battery and 2 fans.
Ridiculously simple. I believe the working fluid was a water-glycol mix.

[DougWantsALeaf]

but it sounds like it was effective

[coulomb]

Yeah Mux posted a picture or a link to a picture that showed a cutaway inside the nv200 battery.

Was it this one?

The nv200 had a horizontal heat exchanger on the back hump of the battery and 2 fans.

The void mux discussed seems to be at the front, near where the cables and A/C pipes connect, not at the back hump. I don't see how the radiator in one corner (if I understand correctly) evens out the temperature of the cells at all. Maybe it's because the pack is sealed; blowing cooled air anywhere might tend to end up everywhere, at least eventually.

From that post:

[brunohill]

There is some ducting to achieve circulation.
https://youtu.be/Oah-UB3d2_8

[coulomb]

Ah, thanks! I can see it in these frame grabs:



The above shows its rough position and size (unfortunately mostly obscured by the gentleman in the foreground), and the below shows it in position:



It looks to me that the cool air is cooling a lot more than "just the electronics" (I can't find that reference in a hurry).

It goes to show that a decent thermal management system doesn't have to take up a whole lot of space, or be particularly expensive or difficult to work into the design.

Please, someone, design a retrofit for various Leaf batteries! Though I can imagine that a retro-fit would be a lot harder than designing from scratch. Maybe whole e-NV200 packs can be fitted to Leafs with some effort? One problem would be supply; there must be (wild guess) 10:1 Leafs to e-NV200s.

[ Edit: Please pardon the quality of the frame grabs; I didn't realise it was at 480p quality till after I grabbed and uploaded the frames. ]

[WetEV]

There is some ducting to achieve circulation.

That video is scary. No gloves.