Fold rear seat to cool battery

I'm guessing you've already figured this out, but that seems to indicate that there isn't enough air flowing through the battery case. Have you checked the battery fan and ductwork?

If the car has been sitting in 115° temps, then it's also starting out at 115°. If it's in the sun, it's a whole lot hotter!! It weighs over 80 pounds, so that's a lot of mass to get cooled down and it needs plenty of air flow. A dirty fan or an obstruction in the ducting will reduce the flow, necessitating a workaround like the one you've discovered.

 

+1 .

Another way to also look at this would be that having the seat up (along with having the back cargo cover deployed) when not in use gives the battery the best chance of having the surface above it getting solar radiant heating. Then prior to leaving put the cover away and fold the seat down and you’ve maximized the cooling the battery area.

Keep that fan and ducting clean though.

 

what happens in vegas, stays in vegas.

 

At 115 degrees and possibly 130+ inside the car, no amount insulating shade is going to help that battery.

That fan kicks on and goes through a duct to cool the battery. Folding the seat doesn't do anything

 

In my Gen4, I have never heard the cooling fan kick on. Even after parked in the sun all day. Could it be that silent? Or should I expect ro hear a noticeable loud fan?

I turn off the radio, and I drive slow to minimize road noise, but I never hear any fan back there. (And yes, my hearing is just fine. )

 

you should check it out, could be broken, and your battery is being damaged.

 

Keep in mind (as mentioned above) Gen2 HV batt cooling fans are prone to getting clogged up and need cleaning if they get too dirty, and there is no way to tell without looking at it, which is a pain. I've never cleaned ours but that's because we have not had any symptoms. Living in 115 deg F probably more need for checking that.

 

Run Silent, Run Deep.

Maybe I never hear the fan back there because I keep the car interior so cool? I always have the AC on, set at the high/low setting. I am a warm wide-body.

egg_salad is making me hungry.

 

The battery is in an enclosed case with intake and exhaust ducting. The main way for fresh air to enter the case is via the intake ductwork. This is where the fan is located. So, flipping down the seat doesn't increase airflow inside the case.

The number one way to ensure adequate air cooling to to clean the fan and visually inspect the black ductwork to ensure that no previous "mods" have crimped or altered these black plastic ducts.

Paul.

 

When I had ScanGauge hooked up on our 3rd gen, it would be indicating hybrid fan was running, typically at speed one or two (out of six), sometimes three or four. For what it's worth, I never heard ours either. It's just not that loud I think, at least at the low to intermediate speeds.

 

i have to say that if you folded the seat and the fan stopped running as much, something happened.
maybe there was something blocking the intake grille and it got moved when you put the seat back down.

 

never mind

 

Battery cooling is highly dependent on the stream of air running over/under/through the battery modules. Certainly the ambient air above the battery is a factor... just not as much as you are giving it.

Next time your grill in the backyard is nice and hot place your hand over it. Now, close the lid and place your hand above it again.... much cooler. The heat is contained by the lid. This is analogous to what the metal case does for a hybrid battery. It traps the heat.

Paul.

 

I was going to make the same point. But I hadn't thought of the great illustration you used.

 

LMAO

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