HV Battery Temps Hitting 116f

Temp was 111 today where I live, the fans were howling at 9am til 4:30pm nonstop parked in no shade with solar panel kicking nice person. Start engine and minute later, ICE goes off. Gear set to reverse and then ICE came back on quickly. Drove for 6 miles; 1 mi HWY + 5 mi under 45 mpg NO FAN/AC all windows down w/sunroof fully open. ICE never went off, EV never lit up. Temp was too high? I waited til 7:30pm drive to the store, same result but this time I turned on the AC recirculate, 5 minutes later EV lit up and HV batter was charging again. Dam summer weather, cant wait for it to go away. Not even solar + fans kept it cool enough to drive w/o AC on.

 

you definitely need the a/c to help cool the battery down.

 

that i already knew, driving with sunroof open is what its all about, even its its hot like hell

 

What do you mean by that?

 

I meant the comment above. My bad for not being specific heh.

 

Guessing the reason for holding the fan speed down until its gets really hot is probably the same reason video card manuafcturers do it for computers. To prevent excessive noise. Most people don't want their computer to sound like it's about to take off like a helicopter when they're just surfing the web or playing a little browser flash game. Toyota might think that the cranking fan all the time might make people feel like the car is struggling.

 

Gotcha, you can modify the fan speed RPMs. I'm old fashion when it comes to fan noise; faster RPMs means cooler temps and louder it is. Who cares how loud it is, loud and proud.

 

What's next for you guys, lowering your engine's running temperature?

I seriously wonder: could you be pushing this too far? If the battery settles in around 35C, on cool evenings, once the everything's warmed up and stablized, just maybe it's by design?

 

I also wonder if pushing the fan hard all the time could overwork it to the point of early failure.

Something to consider.

 

I had one experience with 63 C (145 F), just a lot of hills and stooped the car at the bottom with battery full, the fan does not run when car is OFF. Going back into the car one hour later was an unpleasant surprise, especially going back up the hill without the help from the battery.

Car will try not to use battery when it's nearing 50 C (122) or over that, from around 45-50 C battery will stop charging at around 70% SOC even if you do serious downhill regen but other than that you get normal "boost" from the battery. Bellow 45 C car operates normally. In freezing temps it also "discounts" the battery, I have observed this below -15 C or around there somewhere.