Traction battery Cooler

i wonder if toyota could shed any light on this?

 

Most confusing description of feature!

Found also this (page 150);

■“Traction Battery Cooler” (→P. 127) When charging is carried out using the timer, the hybrid battery (traction battery) cooling function may operate according to the temperature of the hybrid battery (traction battery).
●When the charging mode is set to “Start”, cooling starts at the set charging start time.
●When the charging mode is set to “Departure”, cooling starts approximately 30 minutes before the charging start time. However, if there is no time to finish charging by the timer setting, the hybrid battery (traction battery) cooling time may be shortened and “Traction Battery Cooler” may not operate.

Which makes me think that when mode is set to "Start" the air conditioner is using the external source, while when it is set to "Departure" it is using the traction battery before charging starts.

This may explain several statements in page 128:
●When there is a small amount of remaining charge in the hybrid battery (traction battery), even if the hybrid battery (traction battery) is hot, “Traction Battery Cooler” may not be implemented. May refer to "Departure setting"
●“Traction Battery Cooler” uses the power of the hybrid battery (traction battery) "Departure"? and external power source. "Start"?
• While “Traction Battery Cooler” is operating, the amount of the remaining charge of the hybrid battery (traction battery) increases "Start"? and decreases "Departure"? in a certain range, and does not increase as in normal charging.

There is logic behind all this: "Start" may be set to the starting time of low rate, so the cooler does not start before this time. "Departure" may be set for very near the start up time of the car, so cooler must be finished before charging starts in order to have full battery on departure.

 

I wonder what the logic is that the Traction Battery Cooler is only available for scheduled charging, not when using Charge Now .

 

The good news is that it seems like this part of the instructions can be ignored. The default setting should allow traction battery cooling to take place at the system's whim, the timing of which is apparently "ours not to reason why."

They provide a couple of convoluted ways to turn off traction battery cooling, but since no one can think of a reason why anyone would do that, it seems we can ignore that part also.

 

I've been seeing this message the last few days here since it has been over 90 degrees for the first time since owning the car. The message is quick and I had to see it a few times to register what it was saying but mine shows it is turned off. I haven't turned it on and it still charges when we plug it in. I suppose if anyone should turn it on it should be me. My garage will eventually be well over 120 in the summer. Our Leaf does not like the garage in summer and it runs a cooler automatically. I will work on turning mine on.

 

Charge Now is probably interpreted as: I want it charged as quickly as possible for my next trip. As opposed to plugging-in when no scheduled charge registered where I believe cooling will take place if battery is hot and cooling enabled.
Worth checking.

 

Aside, how does the Leaf cool the battery? All I've seen is that it is a passive air cooled system with no fans.

 

Poorly. No fans, just ambient air passing over the battery case when there is wind or during driving.

 

That messes up my theory a little bit that the default would be Yes. The instruction manual uses two terms, "Above a certain temperature" and "Hot". I would guess that many people would assume these are both the same thing, but my working theory is that these are two different temperatures. "Above a certain temperature" seems to be what determines whether the message appears when shutting off the car. "Hot" is the temperature that traction battery cooling would run.



My theory may still be right, Nancy S saw the message because her battery temperature was "above a certain temperature" however her battery was not "Hot" so that would be why in her case Traction Battery Cooler was set to No. I guess this screen gives her the option to set it to Yes in case she wants it to run the cooling anyway. And the reverse would be true, if the battery was "Hot" at the time of shut down it would be set to Yes, and you could change it to No if for some unknown reason you didn't want to use the A/C to cool the battery during charging.

Seems odd that these decisions are being made when shutting off the car, when you have no idea what the battery temperature will be ten hours from now when scheduled charging takes place. But I guess they figure you have some idea what the ambient conditions will be when charging does take place, so maybe that's why they give you the ability to change the setting. And I am assuming that the choices that you make only affect the upcoming charge session, you aren't permanently changing it. At least that's my current theory. As the hot weather arrives hopefully those who are using scan gauges can monitor battery temperature and be able to shed some light on how this works.

I agree it's worth checking. Toyota could have made this all completely automatic with no user intervention, but instead they give the owner some obscure choices, one buried deep in the MFD settings, the other a bewildering pop-up that is sometimes seen during shutdown. Since presumably the choices made can affect long term traction battery life, it would be nice to know how all of this works.

 

I just presumed that the noise I was hearing from the Leaf when it was charging at night in the summer was some kind of fan but I never really looked into it. Suppose it was just whining like the rest of us in Arizona when it's still above 100 in my garage at 2 AM.

Went out to the car last night about 9PM, it was charging and the AC was not on. The garage was probably 85 or so and the cab was somewhat warmer. This morning it was charged and appeared happy. Got to work and saw the traction battery message for a split second when arriving at work this AM. Temp outside was probably only 70 or so. I'll definitely try to figure out how to turn it on. I wish that it was an automatic function and did not rely on me to make the decision.

 

I am hoping that my theory is correct that it is automatic, and that the only reason yours is defaulting to No right now is because it's not needed while you are still in your balmy winter Arizona weather. Maybe when you get into spring and I would think for sure by summer maybe it will start defaulting to Yes.

 

I'm told that that's how they originally did it, but that after a couple years, they got the crap class-action-sued out of them, and that more-recent Leafs (Leaves?) have a liquid-cooling system.

I'm glad the P.Prime at least has an air-cooling system, but personally, I'm not optimistic that it'll be sufficient here in Central Texas...


iPhone ? Pro

 

That's why the Space Shuttle always had its payload bay doors open the whole time that they were in orbit, even if they weren't carrying any cargo. It's because the doors contained radiators to get rid of the heat. They had a liquid cooling system inside the Shuttle that picked up the heat from all of the electronics, the freon was circulated out to the payload bay doors. In fact they had a mission rule that if the doors couldn't be opened within an hour of reaching orbit, or something like that, they had to cut the mission short and land immediately otherwise the electronics would start overheating.

 

The reason they would start overheating is because they'd run out of water for the Flash Evaporator System (FES) pretty quickly. The FES is how they kept things cool while the doors were closed, which was of course the entire flight up, the time until they got the doors open, and the time after they closed the doors in preparation for entry, descent and landing all the way until they got on the runway and either hooked up to external cooling or got everything shut down.

 

The Leaf is still just passive air. Nissan just switch to a battery chemistry that could deal with getting hot. The little delivery van that uses the Leaf's drive drain does have a fan.

 

Anybody know whether that's the same battery chemistry, or perhaps the same type and vendor, for the P.Prime? Toyota describes them as "high-output batteries with superior durability and heat-resistance."

As I recall, the original Leaf battery at least used a Lithium-Manganese chemistry.


iPhone ? Pro

 

doubtful, unless the manufacturer is the same.

 

There are just too many Li-x cockatails to keep track of them all and small doping differences can lead to impressive improvements so unless the battery is concurrently coming out of the same factory, they are different.

Nissan batteries are their own cocktail; originally manufactured in their factory but since sold to a consortium. There are rumors that Nissan is going to switch to LG sourced batteries for their next Gen LEAF. IIRC Toyota sources from Panasonic. Tesla has joint ventures with Panasonic but has their own recipe. GM sources from LG.

In the overall scheme of things, Tesla chemistry is thought to be tops, followed by LG. Nissan is somewhere near the bottom (but perhaps superior to Chinese BYD?) and I don't know where Toyota slots in but Panasonic is no slouch and they benefit from the Tesla IP even if they do not copy it exactly for their own production. Of course battery chemistry is only one part of battery life: manufacturer decisions regarding allowed C rates, SoC excursions, and thermal management are really important.

 

Anyone figure out the answer to whether you can make the "A/C while charging" question default and stay on yes instead of asking each time? I am asked this question daily now except a few times when it didn't and I thought that it should...figured out that if your passenger opens the door as you shut off the vehicle, the "open door" message comes up and you then don't get the "A/C charging question".