Kwh remaining instead of percentage?

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Joe c

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Hi, waiting impatiently for my Mini SE to arrive, but I was wondering if there was any way to have the display show kwh remaining instead of percentage? To me that would be more useful, because the car displays mi/kwh, so I would think that it would be a lot easier in my head to calculate how many miles I have left if the car just showed me how many kwh were left instead of percentage. With percentage I would have to multiply by total kwh then multiply by my mi/kwh which is an extra step.
 
Also, as a general rule you can just look at the battery %, and under normal circumstances, that’s how many miles you have left - regardless what the GOM says.

I used to use the shortcut @GvilleGuy made (great app!) but have since just found the %=mi method to be the easiest.


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The mi/kWh efficiency shown during the trip also seems to be inaccurate when compared to calculation from % used and distance.

Using 1%=1mi is best and then fudging up or down based on % used compared to current trip distance
 
Once you start figuring out your winter range and SoC % checkpoints then you will be set. The relative range is 1/4 tank of gas in a non-hybrid/PHEV vehicle of your choice.
 
My ‘94 Crapolla 3-speed does <400 km on ~40 litres (about 23 mpUSg) so that won’t work for me. :eek::D
That's a testament to Toyota's reliability! Clearly the Cooper SE can exceed the 1/4 tank '94 Crapolla estimate it's going to be a huge upgrade for you!
 
The miles per kWh displayed in the trip meter is too low. If you compare to the percentage display and do the math it is impossible for the miles/kWh to be correct unless the usable size of the battery is larger than the gross battery size which is impossible.
At 75mph as pointed out the % remaining is pretty much miles remaining. At suburban speeds you can add 50% to the percentage remaining to get miles.
Personally I do the math in my head based on the trip meter mikes covered and the battery percentage display at convenient points (90%, 80%, 75%, 67%, 50%, 33%, 25%, 20%, 10%).
 
Broken record comment from me: for 95% of my SE driving, range does not even enter my mind. And I think most SE owners evaluated the Mini's range for their own use cases, as well, prior to purchasing, to know that day-to-day range calculations would not be needed.

Over 8,000 miles of driving and 5 weather seasons in a mild climate, my average range is 125 miles, so the 1% per mile rule of thumb does not apply to my use case and is simply on par with using the GOM. Once you get to know your SE's range using YOUR driving habits and environment, you'll know the quick estimate value to use for you.

It's a shame that all of this discussion could simply be eliminated if Mini would provide an accurate calculator in our cars. The Mini implementation of this concept is just too conservative to be useful.
 
The mi/kWh efficiency shown during the trip also seems to be inaccurate when compared to calculation from % used and distance.

Using 1%=1mi is best and then fudging up or down based on % used compared to current trip distance

I’m intrigued by this response and Andy’s similar message. I haven’t had my car long enough to evaluate this, but could an explanation be that the decrease in battery percentage is not linear? Case in point, yesterday I decided to see how far I travelled after using 10% battery (100 -> 90%). I went 20.7 miles. Extrapolating that would be over 200 miles range, which I’m assuming isn’t possible. Has anyone evaluated the rate that battery percentage is used given a relatively “constant” driving speed?
 
City driving exclusively can probably get your 1.5x the EPA rated range due to regenerative braking and reduced aerodynamic drag. One would also have to drive in favorable temperature conditions and have optimal low rolling resistance tires (and lighter wheels). The most I have heard of is about 185 miles for exclusive city driving with extreme hypermiling.
 
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I’m intrigued by this response and Andy’s similar message. I haven’t had my car long enough to evaluate this, but could an explanation be that the decrease in battery percentage is not linear? Case in point, yesterday I decided to see how far I travelled after using 10% battery (100 -> 90%). I went 20.7 miles. Extrapolating that would be over 200 miles range, which I’m assuming isn’t possible. Has anyone evaluated the rate that battery percentage is used given a relatively “constant” driving speed?

It's unlikely the battery percentage gauge is perfectly linear, however more linear than most gas tanks due to their irregular shape but that's aside topic...

I have done a highway test where I ran the car down from 100% to 38% and extrapolated that I would get 132 miles of range on a full charge.
I later went on a 115 mile mile drive on the highway where I ran the battery down from 100% to 15%. That extrapolates to 135 miles to a full charge.
While these were different days and routes (the longer one was warmer and I had AC on, whereas in the first I did not need AC or heat, but traffic was a problem in the second) I'm not convinced there is a major difference in the linearity of the percentage reading. Anecdotally I have not seen the gauge drop quicker at lower states of charge either. That said, that first 1% drop does take slightly longer but as you drive further that initial 1% becomes statistically insignificant. I am convinced that purely in town in the right weather, with no AC/heat, close to 200 miles is possible. 170 is easily achievable.
 
I’m intrigued by this response and Andy’s similar message. I haven’t had my car long enough to evaluate this, but could an explanation be that the decrease in battery percentage is not linear? Case in point, yesterday I decided to see how far I travelled after using 10% battery (100 -> 90%). I went 20.7 miles. Extrapolating that would be over 200 miles range, which I’m assuming isn’t possible. Has anyone evaluated the rate that battery percentage is used given a relatively “constant” driving speed?

If the SOC is based solely on current in/out of the battery, the first couple of percent will last longer than the last couple of percent due to the difference in voltage (higher voltage = less current at the same power). The linearity of the battery gauge would follow this graph with higher voltage meaning more range per %.

SmartSelect_20220525-072507_Chrome.webp


It's also totally possible though that MINI is compensating for the voltage difference making the gauge pretty much linear. Either way, the difference is mostly negligible for 95% of the pack
 
City driving exclusively can probably get your 1.5x the EPA rated range due to regenerative braking and reduced aerodynamic drag.

I assumed (based on nothing but intuition) that city driving would be less efficient due to repeatedly accelerating from a stop at lights/signs/traffic, and that the most efficient situation is something like a consistent 50mph on the highway with ACC on. I’ve not had the patience or drive time to do a real analysis though.

All of this speculation is very silly, and could be dispelled if actual data were shared by the manufacturer.
 
I assumed (based on nothing but intuition) that city driving would be less efficient due to repeatedly accelerating from a stop at lights/signs/traffic, and that the most efficient situation is something like a consistent 50mph on the highway with ACC on. I’ve not had the patience or drive time to do a real analysis though.

All of this speculation is very silly, and could be dispelled if actual data were shared by the manufacturer.

That's true for ICE but not for EVs because they aren't wasting gas/power by needing to idle. Starts/stops hurt efficiency but generally less than the aerodynamic drag at high speeds. This generic graph shape is roughly what you should expect for range/efficiency vs speed

tesla-range-vs-speed.webp
 
I assumed (based on nothing but intuition) that city driving would be less efficient due to repeatedly accelerating from a stop at lights/signs/traffic, and that the most efficient situation is something like a consistent 50mph on the highway with ACC on. I’ve not had the patience or drive time to do a real analysis though.

All of this speculation is very silly, and could be dispelled if actual data were shared by the manufacturer.

That's true for ICE but not for EVs because they aren't wasting gas/power by needing to idle. Starts/stops hurt efficiency but generally less than the aerodynamic drag at high speeds. This generic graph shape is roughly what you should expect for range/efficiency vs speed

View attachment 16531

Actually, the main reason for EV's being more efficient in city driving is our old friend, regen. Yes, accelerating from multiple stops uses the battery, but decelerating via regen returns energy to the battery each time.

Though yes, no idling like an ICE helps too, and certainly lower speeds Vs highway driving do.

EV's are the opposite to ICE cars regarding efficiency, they are more efficient in city driving and less so on the highway, due to constant high speeds and not a lot of regen opportunities. It's not a subtle difference either.
 
Actually, the main reason for EV's being more efficient in city driving is our old friend, regen. Yes, accelerating from multiple stops uses the battery, but decelerating via regen returns energy to the battery each time.

Keep in mind that regen does not capture all of the energy used to get moving. Conversion from battery energy to kinetic energy is something like 80% efficient. This also applies to converting the kinetic energy back to battery energy (regen) so round trip efficiency would only be ~64%
 
Keep in mind that regen does not capture all of the energy used to get moving. Conversion from battery energy to kinetic energy is something like 80% efficient. This also applies to converting the kinetic energy back to battery energy (regen) so round trip efficiency would only be ~64%

Very true, that's why I said "returns energy", not "returns all the energy used for acceleration" :) Certainly isn't net zero :) It would have been clearer - and more accurate - if I'd said "returns some energy" o_O
 
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