Is hot summer a problem with Prime traction battery?

I used to lived in New Mexico and I only heard my battery fan located rear passenger side kicked in 1x in one hot summer. And that was my old 2005 prius. If my old prius 2005 can survive in New Mexico, your 2018 prime will not have any issue unless you are close to the wild fire..




iPhone ?

 

Well, to put the question more generally, what is the impact of heat on Gen4 NiMH, Li and Prime Li batteries? We do not know the answers yet. In general cool weather is more kind and gentle for all batteries. We would *expect* much better than the Leaf experience.

In general Toyota USA does not share much if any battery data, so we cannot even tell you how many %Gen2 batts failed. But I am not aware, from posts here, of any *big* problems with PiP Gen4 or Prime.

 

I live in similar summertime conditions (it's 100f as I type this) and I suggest:

No charging in the sun during peak temps (especially 240v); period.
Try to park in shade as much as possible.
Use time schedule charging set for the middle of the night when temps are lowest.

And lastly, don't worry too much about it because batteries do degrade from heat no matter what you do.

 

We occasionally have owners who decide not to use A/C to save MPG. The same A/C cooling you is cooling that battery. Run the A/C and don't feel guilty.

Lets imagine you are driving home from Reno over Donner Summit. Coming down, the Prius will try to convert kinetic energy to rotational energy to electricity to chemical energy. It is about 30% effective, so 70% is turned into heat. (Normal brake convert 100% into heat)

Switching to B mode will encourage the Prius to use the engine as an air pump to slow the car. (less so in the Prime) Giving the computers more choices means they will choose to conserve the battery more. (While this can lower MPG, heat is bad, braking is good)

I would not worry as much about heat on level ground, as the computers have lots of choices. Consider sun shades, legal tinting, (if you have the back very dark, park facing north so the front is away from the sun) parking in shade, etc.

I am not a Prime owner, but I believe it will slow charging to avoid overheating. I know you can delay charging to cooler (perhaps cheaper) times of day.

If you carry shaggy pets or other fibrous loads, clean the battery fan every year. The rest of us only need it every 5 years.

California Tint Laws - 2017 & 2018 - Car Tinting Laws

 

im concerned about this too. i bought the prime just to charge at home, commute to work, charge it at work, then commute home. not use one drop of gas except on extended driving (EV's 30 miles then hybrid mode.) now that's it's starting to get warm here, 80's 90's, im getting this message every day.

i have a scangauge. i was thinking of just keeping the battery fans on 100% all the time. or just hardwire them, with a switch or something, bypassing the computer to make it run 100% while the car is on.

i have my AC set to between 70 and 75. ive noticed the charger is under the right rear seat. i dont know if the AC is actually cooling the interior. it be midnight and i open the car to get my key or wallet whatever and the inside is ~20* hotter than outside the car.

i just cant believe it takes that much energy to drive ~22 miles, in less than 45 mins, each way and can drain the battery beyond 0% (hybrid mode kicks in.)

i bought extended warranties with the car with this driving mode in mind. but it's still a back-of-your-mind thing.

 

Yep -- the car will ask permission to cool down the battery with AC before charging. It is a bit of a pain though -- the message only appears for a a few short seconds after the car is shut off and you have to answer ´yes´ quickly. So far as I know the default value is 'no' and you have to enable AC cooling every time. Otherwise the car will wait for the battery to cool down from ambient air first.

The interesting detail about the air cooling is that it comes from the cabin air. So during driving if your cabin is cool, the battery is happy too. I make it a point to always have the fan on and recirc turned off (with or without cooling) unless it is cold outside so the the battery is well ventilated.

 

My prime has asked to "use AC to cool the battery a few times". It goes away so fast that I miss the opportunity to say yes. Any way to go back and let the car use the AC after the message goes away?

 

A guess - turn the car on and off again.

 

I'm looking at PHEV's for the GF.
You're saying you have to actively get involved with keeping the pack cool by cooling the whole interior of the car?

It's ONLY A FAN?

What about outdoor public charging, in the sun, in Tucson? What is the rate of charge going to the pack in those situations?
What about the dead of winter?

 

I am saying some owners decided they could 'macho' through the heat, and that is a bad plan. If it is uncomfortable to you, it is too hot for the battery.

I have not been to Tuscon (Kitt Peak Observatory) since 1977, well before the Prius. It never exceeds 12 Amps, the step back I hear most often is 8 Amps. The car will ask you if it can run A/C during charging, if the battery exceed a certain temp. If you do not say yes, it does not start charging until the battery cools below that threshold.

 

I believe the gen 1 had 'cool' vents to get air from the outside.

 

>Driving home from the pool, high 90's, low humidity !?! Just feels good!
>>3.3kW L2 charging for the Prime.
>>>So driver involvement is required with the Prime if you want to charge in hot weather..? by cooling the whole cabin just so some of that cool air gently wafts through the HV pack..?

And what about in very cold weather? Is the whole cabin heated so some of the warm air keeps the pack happy?

Sounds like another work around....
Some PHEV's have a dedicated TMS for the pack. No driver involvement. Pack isn't related to the cabin temp.

On the Gen 1 Prius, I believe those were air exhausts for the pack. It still depended on the cabin temp for the pack.

 

Gen 2 as well.

 

It’s gotten really hot in Sacramento and the car only charges at level 1 speeds outside in public charging stations. Really wish this car had better cooling technology.

 

OK, so just to verify this... we should always be saying YES to that question when/if prompted?