After 12V disconnect, what should the range be?

[Jscifres]

Hi all,

After averaging 2.2 mi/kWh since owning the car, I would expect to see my maximum range readout (with all climate control and accessories off) say 92 miles (2.2 miles/kWh x 41.8 kWh battery size) but it was showing only a maximum of 83 miles available. So, am I dealing with a defective battery?

I'm not sure taking it to the dealer will help much here, as I don't even know if there's a problem and I don't expect the service guys to have much knowledge on the subject. I can just envision them saying that it's cold outside and for me to go home.

So after some research, I decided to reset my car's mileage numbers/efficiency history by disconnecting the 12V battery system and start from scratch. After performing this procedure, I'm up to 125 miles max range, or 3.0 mi/kWh (125 mi / 41.8 kWh).

Seems reasonable...

Except that I thought I'd read someone report that the baseline efficiency was actually 3.5 mi/kWh... in order to impress potential new buyers with the potential range of the car.

So, anyone have any thoughts on which is correct?

Thanks!

 

[Dsinned]

You probably read that "someone's" post from me on this subject, but actually it was originally from a post by a fellow member here named Tony. In his post he reported a battery disconnect resulted in a reset to his max. range of well over 140 miles, or driving efficiency of ~3.5mi/kWh. By doing the math, 3.5mi/kWh * 41.8kWh = 146 miles!!! Then, I added in my post that this "default" might come in handy to impress potential customers on their first test drive, but I was merely speculating from what I heard from Tony. I have never done or witnessed a battery disconnect, so I cannot confirm this and so YMMV! :mrgreen:

I think a max (default) range of 125 miles is much more likely in retrospect, because a driving efficiency of 3.0mi/kWh is definitely doable in the real world, whereas an "average" of 3.5 is much less likely and only possible under extremely favorable conditions. A max. range of 146 vs. 125 vs. whatever, would be important to display as a "typical" default estimation, so the driver does not expect more range after a fully extended charge vs. what he actually would get in the real world, under ALL possible conditions.

Hopefully, Tony will further explain how he got such a high number from doing a battery disconnect.

 

[Jscifres]

Shoot, I was hoping that my memory was wrong... Looks like we have two different data points right now. I agree that the 125 miles is more attainable and therefore the more appropriate default... But, that doesn't mean that Toyota (or would it be Tesla?) set it up 'appropriately', does it?

I should note that my numbers are all based on a full standard charge, not the extended charge. The standard charge capacity is 41.8 kWh, correct?

 

[Dsinned]

I should note that my numbers are all based on a full standard charge, not the extended charge. The standard charge capacity is 41.8 kWh, correct?

INCORRECT! Per Toyota, the RAV4 EV's standard (or "normal") charge USABLE capacity is 35kWh. Conversely, the extended charge USABLE capacity is 41.8kWh.

If you are saying after your battery disconnect, you got 125 miles maximum indicated range after a "STANDARD" charge, then that would have resulted from a (default) multiplier of 3.57mi/kWh, because 35kWh * 3.57mi/kWh = 125 miles. Or, if you use the same default for an "extended" charge, the max range is 41.8kWh * 3.57mi/kWh = 149 miles.

As I recall, the latter is closer to what Tony got for an "extended" charge after his battery disconnect, which obviously would be based on "best case" battery and driving conditions.

 

[Jscifres]

I should note that my numbers are all based on a full standard charge, not the extended charge. The standard charge capacity is 41.8 kWh, correct?

INCORRECT! Per Toyota, the RAV4 EV's standard (or "normal") charge USABLE capacity is 35kWh. Conversely, the extended charge USABLE capacity is 41.8kWh.

Awesome! Thank you so much for the clarity on battery capacity! Now it's all slowly coming together for me. And it looks like my car is behaving perfectly normal.