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The "juice" is measured in kilowatt-hours (kWh) and for the 2017-2018 Bolts it can be read off the OBD-II port on PID #2241A3. Lengthy discussion for the custom PIDs including this one can be found in this thread:

You can get a Bluetooth OBD-II dongle and add the PIDs to a smartphone app (e.g. Torque Pro) that interfaces with the dongle.

Alternately, you can get a programmable gauge display that connects to the OBD-II port and add the PID in question, as I have done in this thread (relevant number is shown under "Chg kWh" on the screen):
It does the job of letting me know the remaining capacity at any time quite well, and frees up my smartphone for other tasks.
 

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Is there anyway I can tell how much juice (how many kilowatts) I still have in my 2017 Bolt at anytime?
I just use the bars on the gauge. For more accurate percentage, I log into my.chevrolet.com on my onstar account to get how much percent (one can also use the phone app). But, one has to do some math. Just logged into my.chevrolet.com and my battery is at 48%. Assuming a nominal 60kWh battery pack, I'm at 28.8 kWh left in the "tank". But the gauge shows 10 bars left which would imply the battery is half full or 30kWh. The bars are 3kWh each or 5% increments. So you only really know for sure within 5% right after you drop a bar.

Or you really meant kilowatts available. In that case, I think you can get full 150kW above 85% state of charge. Also the Bolt will start to limit power if temps get too hot or battery is getting low. The guys racing the Bolt know more about these issues.
 

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It depends how accurate info you need and what load will be applied to drain it.

Wh is what you are looking at.
However, it is not just like volume of petrol, say. You cannot measure it just like that.
It is dependent on two things - Voltage of the cell (V) and energy it has, for this let's just use current*time (Ah). We should talk about Joules and time, but that would be too deep for this scenario.

Now, imagine it. Fresh, full battery is about 400 V (there are 96 cells, each at about 4.15 when full).
If the cell has a total capacity of 150 Ah, you will have 60 kWh (400 V x 150 Ah = 60'000 Wh, that is 60 kWh). But specs says resting voltage is 350 V (for capacity measurement, by EPA) and you would need actually 170 Ah to get 60 kWh. And then, if you get 400 V and 170 Ah, you then get 68 kWh...
So. that is the first culprit.

The moment you start draining the battery, voltage will start dropping... which leads to the second problem - lower voltage, less energy can be produced. And the fact is that at lower charge states, the battery will be protected to drop below certain voltage, hence you cannot pull full 450 A current from it.


So in short - at any given moment you can only get and estimate.
What is the best way?
Look on your screen. It says how much was used. Then knowing how much you charged (say 80%, 90%, or 100% - that is 48 kWh, 54 kWh, or 60 kWh) you can estimate how much is left.
 

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The "juice" is measured in kilowatt-hours (kWh) and for the 2017-2018 Bolts it can be read off the OBD-II port on PID #2241A3. Lengthy discussion for the custom PIDs including this one can be found in this thread:

You can get a Bluetooth OBD-II dongle and add the PIDs to a smartphone app (e.g. Torque Pro) that interfaces with the dongle.

Alternately, you can get a programmable gauge display that connects to the OBD-II port and add the PID in question, as I have done in this thread (relevant number is shown under "Chg kWh" on the screen):
It does the job of letting me know the remaining capacity at any time quite well, and frees up my smartphone for other tasks.
While it might be fun to be the defective detective and junior scientist, I go by the number on the instrument panel. Summer charge on my '19 Bolt has usually been a little over 350 miles. GM will never get a look at it. Yeah, it's the big center number, not the top one.
 

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While it might be fun to be the defective detective and junior scientist, I go by the number on the instrument panel. Summer charge on my '19 Bolt has usually been a little over 350 miles. GM will never get a look at it. Yeah, it's the big center number, not the top one.
That’s good for practical purposes, but if its nickname Guess-O-Meter (GOM) is any hint, it’s only an educated guess of how much range the car has left. OP was asking about finding out how much kWh is left, and GOM doesn’t provide that info directly - hence the technical explanation.
 

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Discussion Starter #8
While it might be fun to be the defective detective and junior scientist, I go by the number on the instrument panel. Summer charge on my '19 Bolt has usually been a little over 350 miles. GM will never get a look at it. Yeah, it's the big center number, not the top one.
350 miles? :oops: How do you get that many miles? What's the trick? I can only get 235 miles max, fully charged with Hill Top Reserve turned off. Please share your technique.
 

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I managed to average 6.0 or more, but it takes a lot of effort - no faster than 35, maybe 40 mph, avoid stopping as possible. Gentle acceleration, like 50 kW and you might get there.

So then... why would I really do that? Only to prove it can be done.
The rest of the time is max 4.5 miles/kWh or so.
Now averaging 3.1 with 0 C outside.
 

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I managed to average 6.0 or more, but it takes a lot of effort - no faster than 35, maybe 40 mph, avoid stopping as possible. Gentle acceleration, like 50 kW and you might get there.
See, this is why people have different results... To me, 20kW is "gentle" and 50kW is "moderate".
 

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I use percentage scale of the power.
For me gentle in Bolt will be 30% of power, that is about 50 kW.

In 500e that would be more about 25 kW.

Then, from there, 35-60% moderate, above 70% hard.

If I had a car with 300 kW motor... well, yeah, that is the weak point here as going 100 kW would be quite fast there.
But then 40 kW with 500e would be half power, right? so it is all very subjective.
 

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Yep, that is exactly my point.
But you know what?
I keep proving myself that it is not so much the power when accelerating used, but the energy "returned", or call it braking power, responsible for your overall result.

In other words: going from +30 kW to +90 kW is not as bad as from -10 kW to -50 kW (+ was used for flow to the motor, - to return to the battery).
 
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