Battery Drain - Hot Weather?

Do you have a clue what temperature this “safe switch†kicks in?

I’m planning battery heater for winter times, and this info can be very useful…

 

No idea. Perhaps the dealer has the info or maybe just the car holds it in its computer.

The a/c was on high so the inside cabin temp was quite low and the vent wasn't blocked to the battery. I'm guessing the number of amps drawn from the battery and pushed back in when braking heated it up. The area directly above the battery was quite warm (not hot) to the touch.

 

Ok, thanks, I better keep it just barely over 0 Celsius, like 5 degrees. So I have plenty room before safety levels. If it warm to hand it is has to be more than 36 Celsius, about 40?

I just have problem to find pillow heater that does look like car proof.

 

I know this is an old thread, but just in case anyone else - like me - happens to come across it let me just say, everyone - relax!

ALL batteries have higher discharge rates in heat (how many of you store flashlight batteries in the refrigerator? Raise your hands!) The Prius is no different. The hybrid battery will always maintain a rserve - it will never become un-chargeable. Others are right in saying that the engine, the ICE will kick in to provide some charging.

Stop and go traffic draws heavily on the hybrid battery, as it is used to assist with getting the car going at low speeds.

As to others' concerns about having the car go dead in desert heat - no chance. You'll continue driving, although with much lower fuel efficiency as it will be all gas, no hybrid assist. In this case, the small Prius engine may or may not match the fuel efficiency of other mid-sized cars. Expect low/mid 20mpg on the highway, 10-20 mpg on side roads.

While driving with no reserve in the battery will not damage the car, driving without any fuel will. Quickly. The hybrid battery is designed to assist, not fully power, this mid-sized vehicle. Running out of gas (in the Mojave or elsewhere) will cause the battery to kick in 100%. You'll go a few miles, deplete the battery, and fry its innards shortly there after. Not only will you be dead in the water, but you'll have a dead Prius requiring a new, multi-thousand dollar hybrid battery.

Bottom line: No charge - good. No gas - Bad. Very, very bad. (Be safe - fill up at 3 bars! The Prius is also notorious for having a "Guess Gage" rather than a "Fuel Gage"!))