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Discussion Starter #1
Does anyone know what the usable capacity of the 2020 Bolt should be? I’ve had a 2020 Bolt for about 3 months and 2500 miles. I tested the capacity last week by driving from fully charged down to 1%, which used 63.7 kWh as reported on the energy consumption screen. That means my usable capacity is 64 kWh rather than the 66 kWh advertised. Is that normal?

If you’re interested in the details here they are. I drove a total of 232 miles. 227 of those miles were on the freeway with the cruise set on 70 mph, which also matched the speed on a GPS app. The other 5 miles were getting to and from the freeway and driving around my neighborhood for a mile or so to get down to 1% at the end. The temperature was low to mid eighties. Wind was light. The roads were dry, and there was little traffic. My consumption was 3.64 miles/kWh, including energy used for A/C, which was set on auto at 73 degrees and accounted for ~4% of the total energy consumed. Overall a pleasant way to spend 4 hours on a weekday morning.

My thanks to Eric of News Coulomb for the inspiration and technique.
 

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Actually, you use 63.7kWh and assuming the measurements were accurate, 99% of the battery capacity. That translates to 64.34kWh total capacity. But how did you measure the 1%? If I had to guess, I doubt you've lost any capacity - it's just that what is being measured is not truly 99% of the battery capacity being discharged.
 

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Discussion Starter #4
Thanks for the reply. I used the MyChevy app while driving with Apple CarPlay and noted the total energy consumed at the point when the SOC dropped from 2% to 1%. There aren’t any decimals shown so I don’t really know if that’s actually 1% or 1.49999%. So you’re correct there is some ambiguity in the measurement, but any way you calculate it it’s less than 65 kWh. I’ve also seen two different YouTubers do this test. One calculated 64 kWh capacity, but the other got 66. The only difference in the procedures noted was the one who go got 66 kWh made sure the battery was warm by driving the car hard for a while and topping up the charge immediately before starting the test. He also drove the car completely down to zero SOC. That was Kyle from Out of Spec Motoring by the way.
 

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Discussion Starter #4
You cannot use miles to calculate battery capacity, but I imagine that out of the 66 kWh nominal capacity, you are doing very well.
I didn’t use miles to calculate capacity. I used total energy consumed (63.7 kWh) divided by percent of full charge used (99%) which equals 64.3 kWh usable capacity in my test, which isn’t bad in absolute terms. However, if I should have 66 kWh then my battery capacity has degraded 2.5% in three months which would be a concern.
 

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Considering that my 2018 Bolt had about 58.3 to 58.6 kWh of usable capacity initially out of 60.9 kWh nominal (certified by the Korea Ministry of Environment), I would consider 64 kWh to be a reasonable initial usable capacity for the 2020 model year, for which KME has certified it to be 65.94 kWh. Certain amount of capacity is withheld to protect battery life.
 

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Discussion Starter #6
Considering that my 2018 Bolt had about 58.3 to 58.6 kWh of usable capacity initially out of 60.9 kWh nominal (certified by the Korea Ministry of Environment), I would consider 64 kWh to be a reasonable initial usable capacity for the 2020 model year, for which KME has certified it to be 65.94 kWh. Certain amount of capacity is withheld to protect battery life.
Thanks! That’s the kind of info I was looking for. I haven’t found anything official from Chevy online or in the manual, but I figured someone on here would know.
 

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For those curious, there's a list of EVs certified for Korean government subsidies here:

Cheat sheet:

Number of seats
Top speed
Range (Normal) / (Cold)
Battery type and capacity - all are listed as Li-ion
Amount of central government subsidy (in 10 thousand KRW) - local government provides additional subsidy
Manufacturer's telephone number
 

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Thanks! That’s the kind of info I was looking for. I haven’t found anything official from Chevy online or in the manual, but I figured someone on here would know.
As Eric probably explained to you you need to track capacity over time. One test is not statistically useful. It's a marker, but just a marker. Keep track over a period of weeks or months and report back.

I've been tracking battery capacity for 2.5 years and I can report that the number bounces around a lot. There's a clear trend, but individual measurements vary within a few kWh.

Paul
 

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As Eric probably explained to you you need to track capacity over time. One test is not statistically useful. It's a marker, but just a marker. Keep track over a period of weeks or months and report back.

I've been tracking battery capacity for 2.5 years and I can report that the number bounces around a lot. There's a clear trend, but individual measurements vary within a few kWh.

Paul
Right. Remember that the car is constantly taking energy out of the battery and putting it back in (regen). The calculations on the kWh used are based on efficiencies related to that usage and can vary a bit depending on conditions, the balance between power usage and regen, how many times the battery has been cycled, etc. Track it a few times and see how the numbers compare.

Mike
 

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Based on the 2020 Bolt EV I reviewed, the initial capacity is definitely close to 66 kWh. As others have stated, though, a single discharge session will get you close, but it's not necessarily spot on. I've noted a +/- ~1 kWh margin of error between tests. A 2020 Bolt EV owner should probably expect about 65 kWh of usable capacity from factory.

The 60.9 kWh usable (per the Korea Ministry of Environment) for the 2017 to 2019 Bolt EV also aligns with my experiences, and the ~58 kWh usable that 2017-2019 Bolt EV owners now see appears to have happened after Chevy updated the BMS software. I saw approximately 2 kWh of lost capacity after having the update done, though, I was already down to 58-59 kWh usable capacity at that point.
 

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Discussion Starter #12
Thanks for all the feedback. I’ll definitely try the test again in the future and post an update. I’m thinking I might try it at 65 mph instead of 70 to see how much impact that has on the range and efficiency. Obviously the speed shouldn‘t have any impact on the capacity measurement.
 

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Thanks for all the feedback. I’ll definitely try the test again in the future and post an update. I’m thinking I might try it at 65 mph instead of 70 to see how much impact that has on the range and efficiency. Obviously the speed shouldn‘t have any impact on the capacity measurement.
Yes, the speed should have no impact. The only thing I've noticed that produces significantly different results is weather. Basically, summer weather appears to consistently show about 1 kWh higher usable capacity than in winter, which makes sense because the colder battery temperatures increase internal resistance, resulting in energy consumption that isn't measured by the BMS.
 

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I don't know about Kwh, etc. but Ithink I have set a new record for the GOM mileage If not a reocrd, certainly a personal best for me. Check it out!
29835
 

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Actually that 5.4 message is a little erroneous. That figure changes with any change in driving. It kind of floats up and down from a low of 3.2 to 6.1. Never steady. I deliver meals on wheels and my route is about 45 to 50 miles per day. Usually takes me about 1.5 hours of rural driving, up modest hills and down the other side. I learned long ago, driving ICE cars, that any time you step on the pedal (brake or accelerator) costs you money. I drive exclusivly in Lo Range and I have occassionally been able to drive the entire route without stepping on the brake at all. It is a fun car to drive!
 

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I drive exclusivly in Lo Range and I have occassionally been able to drive the entire route without stepping on the brake at all. It is a fun car to drive!
Ditto. My commute is 65 mi each way. the first 35 miles are back highway, rolling hills with ~2500 ft elevation drop. I charge to Hilltop Reserve limit (~88%) so I regen the first half of my commute, my highest efficiency after that 35 mile section was close to 15 mi/kWh! The remaining 30 miles is 50 MPH expressway, and 55 MPH Interstate. My best efficiency going to work was 9.3 mi/kWh. Returning home on the same route, it is uphill so I lose a lot of what I gained in the AM, but my best round trip was 6.5 mi/kWh for the 130 miles. True, that was summer and mild temps, winter can be brutal in CO, and the Bolt loses at least 20-25% on average during winter months.

My best GOM reading was right around 350 (middle number), again with HT Reserve charging, and toward the end of that first leg of my morning commute.

I probably stop no more than 5-8 times on my typical commute, and it is rare when I use the brake pedal for anything but starting, and signaling that I am stopped at an intersection to the cars behind me. When I take the Interstate (rare due to construction and traffic), I game the rush hour stop and go, and am typically able to avoid touching the brake pedal, relying on L and regen paddle. Takes the boredom out of commuting!
 

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Thanks for all the feedback. I’ll definitely try the test again in the future and post an update. I’m thinking I might try it at 65 mph instead of 70 to see how much impact that has on the range and efficiency. Obviously the speed shouldn‘t have any impact on the capacity measurement.
My advice is to get Torque Pro, and Telek's PIDs.


You will unfortunately not be able to use the capacity PID, as it has now been blocked by GM. However, You will be able to see the voltage of every one of your 96 cells (actually 3 cells in parallel). This will tell you how closely they matched the capacity of the cells in your Bolt. Some Bolts have very closely matched cells. Others, like ours, have some cells which have considerable less capacity. Of course, the battery is only as "big" as its weakest cell.
 
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