How does the gen5 prime/phev manage traction battery temperature while charging in warm conditions? I know the gen5 hybrid has a fan (with a filter) that circulates cabin air through the battery to cool the traction battery while charging. But the phev lacks this fan and filter. l have read that the car uses coolant lines to manage battery heat. OK, but does that mean that the air conditioner or heat pump starts up on its own while the car is off (but plugged in and charging) to cool and circulate coolant through the battery cooling system?
Actually, there are options to disable heating and/or cooling while charging, so you're free to stop it using power for temperature control. But then it would need to slow or stop charging while the battery wasn't at a good temperature.
Thanks, interesting. Any idea if this also happens when you charge a rav4 prime/phev in hot conditions, will that car also automatically turn on the heat pump to cool the battery while the car is off and charging?
Not exactly. The rav4 prime/phev also has the cabin air battery cooling fan (with filter) just like the hybrid rav4 and hybrid gen5 prius. And it turns on during charging. So when a rav4 phev is charged in hot conditions, do both systems (battery cooling fan plus heat pump with circulating coolant) turn on?
Correct, it's using the cabin air for cooling, same as the G4 Prius PHEV. But the overall behaviour is the same - as necessary when charging it will run the A/C to cool the cabin or turn on the battery heating elements, unless you've disabled those options. Edit: Just noticed you're asking about the fan. Subtle distinction there. Not 100% sure, but I'd imagine it would always use the fan. The cooling option would be about whether it runs the A/C to cool the cabin.
So the rav4 phev will turn on the a/c to cool the cabin air which will the cool the battery? Or it will turn on the heat pump or a/c to cool coolant in the lines that run directly through the battery? Or both?
Oops, okay, I'm out of my depth here - I'd forgotten the RAV4 had liquid-cooling, something I should have remembered. I thought you were saying it had only battery air-cooling, so I believed that and inferred behaviour from the G4 Prius. Having both sorts of battery cooling seems unlikely, so I've checked, and it seems that the air cooling you're talking about is for the charger, not the battery. That's the same as the G5 Prius, except the Prius doesn't have any visible vents for the charger fan. So, like the G5 Prius, I'd expect that the cooling option would be about directly cooling the battery with the refrigerant, and it's not going to bother running cabin AC just to help the charger fan.
No worries, thanks for your input. Where do you go to check to learn more details about which systems work when, and on which car?
Toyota's (paid) technical doc services have a "New Car Features" document for each model which goes into that level of detail.
The new-car features (NCF) manual will not help you on this, as it doesn’t discuss owner-operating details like in the owner’s manual. The owner’s manual is your best friend on this. In the Gen 4 Prius Prime PHEV, I have the A/C air-cooling option enabled, but I have never seen it kicking in. I have seen something like “Would you like to turn on the A/C to cool the battery?” on the display a couple of times, but it disappears in two seconds before you can take any action. I am guessing it might never kick in in Gen 5 either. Gen 6 (RAV4 PHEV) now has coolant (as in ethylene glycol, not A/C refrigerant) cooling that couples with the engine cooling circuit through a heat exchanger, which can both cool and heat the battery. The system also has a high-voltage PTC coolant heater. So, it is an improvement over both Gen 4 and Gen 5.
