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While driving with more or less stable conditions (no changes in climate settings, average speed etc), the range displayed on my GOM is jumping back and forth by about 20 miles. It changes approximately every five minutes or so. The 20 mile delta is constant but the average range is decreasing as expected. I have a 2019. Has anyone else seen this?
 

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I also have a 2019, the GOM has been steady - decreases or sometimes increases as I expect. Have about 1,800 miles on it.

If you have very low milage, it may still be calibrating to your driving style???????
 

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I just remembered, the 2019 has separate controls for heat and cool as well as automatic. Be sure the automatic, heat and cool are all off if you want to test the effect of HVAC. However, I have been using both heat and cool and not seen any jumping around. So I doubt the HVAC is causing that type of range change.
 

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A couple weeks ago our 2017 model suddenly started giving irregular GOM readings in SoCal. Other than the somewhat increased use of the heater early in the morning, nothing of substance to explain the 50 mile drop in guesstimated range. Maybe this problem transcends one year's model.
 

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Two months ago my 2019 clocked out 1.5 miles from home. According to the Min Range GOM I should have had 10 miles to spare, checked Min Range at 60 miles and then 20 miles from home. The last 15% capacity, according to the left gauge, dropped out within the last 8-10 miles. I had a glimpse of the Energy Used since last full charge gauge at 48.0 kWh which is consistent with my 80% Target Charge that morning. I hadn't been watching the Energy consumed gauge from the infotainment screen, only the left dash gauge which I assumed represented remaining capacity. OnStar paid tow charge home where I immediately plugged into my L2 charger. It took about 13 kWh, or two hours, to come off of it's out of energy state. I couldn't help but think what that would mean if I only had a 110 outlet available, let alone if I may have needed any heat during the next 13 hours to get on my way.

The experience brought my attention to compare Infotainment Energy Detail: comparing Energy Used to the "Fuel Gauge".

I apologize in advance for the blurry dash picture but you should be able to make out 25% capacity (15 kWh) remaining while the Infotainment screen reads 51 kWh Energy used. That is a Maximum difference of 6 kWh or about 18 miles at 2.9 m/kWh. If I had added energy during the trip, I would have no idea of this discrepancy. Energy Remaining would be a most useful metric, particularly if one has added energy along the way.
 

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Energy Remaining would be a most useful metric, particularly if one has added energy along the way.
I try to look at the remaining bars on the "fuel" gauge. You have to watch when the previous high bar ticks off though to get a good feel of remaining battery. Twenty bars for 60 kWh makes out to 3 kWh per bar. Your gauge in your picture I think shows 5 bars or 15 kWh left. But like a gas tank one shouldn't consider the last bar useable. From your picture, I don't know how long you have driven on the high bar so I'll subtract that one bar and the last bar so that's 3 bars of useable battery or 9 kWh. Then you can watch your actual miles per kWh on the infotainment system (edit: or the trip meter as you reset it). Since you're using the heater for your feet in the picture, I'll assume 3 miles/kWh (edit: pic has 2.9) so you have 27 miles left where your GOM says 49 (little blurry).
 

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Two months ago my 2019 clocked out 1.5 miles from home. According to the Min Range GOM I should have had 10 miles to spare, checked Min Range at 60 miles and then 20 miles from home. The last 15% capacity, according to the left gauge, dropped out within the last 8-10 miles.
Sorry. You battery, or the BMS software, is screwed up. You should, in fact, be able to count on the last bar as being accurate. If, like dfwpev, and gern_blanston, you find your range/battery capacity going from 2 or 3 bars to nothing in a few miles, you need to report this to GM ASAP, to get to the bottom of this problem.

See my capacity tests, or NewsCoulomb's, for how a normal battery behaves.

https://www.chevybolt.org/forum/9-2...17-battery-degradation-measureability-11.html
 

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Sorry. You battery, or the BMS software, is screwed up. You should, in fact, be able to count on the last bar as being accurate. If, like dfwpev, and gern_blanston, you find your range/battery capacity going from 2 or 3 bars to nothing in a few miles, you need to report this to GM ASAP, to get to the bottom of this problem.

See my capacity tests, or NewsCoulomb's, for how a normal battery behaves.

https://www.chevybolt.org/forum/9-2...17-battery-degradation-measureability-11.html
Yes, this is exactly right. My vehicle will track down to a single flashing orange bar. Each bar represents 5% of your overall battery capacity, and when my last bar is flashing orange, my car still has between 0% and 5% capacity.
 

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A properly functioning Bolt gives plenty of warning of shutdown. The bars turn orange, the car tells you to charge soon, the car says it is reducing power, then it says low and the last bar flashes. All of this is to scare the heck out of you to prevent just what apparently happened to you. If this didn't happen, and in a logical, orderly fashion, there is in fact something wrong with your car. If it did happen, and you weren't paying attention, then that is on you.
 

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Two months ago my 2019 clocked out 1.5 miles from home. According to the Min Range GOM I should have had 10 miles to spare, checked Min Range at 60 miles and then 20 miles from home. The last 15% capacity, according to the left gauge, dropped out within the last 8-10 miles.
As others have said, this isn't how it's supposed to work.

The best advice is to talk to GM about it, perhaps there is a problem with the car. But it's tempting to try to speculate. @Sean Nelson's worry about the battery software not being updated is unlikely, since you have a 2019 model.

I think it might be an issue with the new more flexible charge termination feature that is new in the 2019 models. You said you charged to 80%, which is lower than the 87% 鈥渉illtop reserve鈥 that prior years could charge to if they didn't want to charge to 100%. My understanding is that its much harder to do cell balancing when the charge is a lot less than 100%. If the batteries weren't well balanced (some above 80%, some below), that'd explain why the car thought it was doing well and then had a horrible sudden realization.

This leads to the question, when did you last charge to 100%? And would you be willing to try an experiment where you charge to 100% and then run battery down pretty low?
 

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Sorry. You battery, or the BMS software, is screwed up. You should, in fact, be able to count on the last bar as being accurate. If, like dfwpev, and gern_blanston, you find your range/battery capacity going from 2 or 3 bars to nothing in a few miles, you need to report this to GM ASAP, to get to the bottom of this problem.

See my capacity tests, or NewsCoulomb's, for how a normal battery behaves.

"Got home with 20.8% left. With 87% going to propulsion, I averaged 3.3 mi/kWh overall, 3.8 mi/kWh for propulsion. Not bad, as I was pushing a lot of water off the road. Looked like a boat wake for some of it."

I'm hesitant to install the torque pro, which is the only way to know the remaining capacity to the tenth kWh. I've seen many Newscolumb videos and have assumed all along the Left Dash SOC would represent my useable remaining capacity to within 3 kWh or 5%.
 

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Yes, this is exactly right. My vehicle will track down to a single flashing orange bar. Each bar represents 5% of your overall battery capacity, and when my last bar is flashing orange, my car still has between 0% and 5% capacity.
Yes, I saw what you are describing. It actually began at about 10% SOC maybe 8 miles from home. I had passed over a grade which requires up to 50 kWh for a few seconds to maintain 65 mph then it tappers back to the 15-20 kWh cruise leading into a like grade down where it will actually regen at 65 mph. I was prompted to enter a low energy state when the speed dropped. My infotainment screen went dark as I recall, this happened in November 2018 and I was confused as to how and why. My last check, a small town 19 miles from home, where I might plug in for a few miles range, my SOC was 20% or about 12 kWh, I was feeling anxious but comfortable. I've noticed you, and A better route planner, run down into the 5-10 % range to a charge station.

In a nutshell, without torque pro, the remaining capacity is represented by the far left dash gauge to within 3 kWh?! I find it remarkable we are discussing the energy equivalent of less than 12 oz gas, 16 oz in a pint, 2 pints in a quart!
 

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As others have said, this isn't how it's supposed to work.

The best advice is to talk to GM about it, perhaps there is a problem with the car. But it's tempting to try to speculate. @Sean Nelson's worry about the battery software not being updated is unlikely, since you have a 2019 model.

I think it might be an issue with the new more flexible charge termination feature that is new in the 2019 models. You said you charged to 80%, which is lower than the 87% 鈥渉illtop reserve鈥 that prior years could charge to if they didn't want to charge to 100%. My understanding is that its much harder to do cell balancing when the charge is a lot less than 100%. If the batteries weren't well balanced (some above 80%, some below), that'd explain why the car thought it was doing well and then had a horrible sudden realization.

This leads to the question, when did you last charge to 100%? And would you be willing to try an experiment where you charge to 100% and then run battery down pretty low?
My 7500 mile service is coming up next week, I'll bring it up to the dealership but I value this group's experience.

The picture I posted is from a 100% SOC. Typically I charge to 100% if I'm planning on consuming over 25% next day. I prefer to minimize the time spent at maximum charge. Comparing electricity to water, my understanding, is voltage is like pressure and amperage is like volume. From my experience, with 3 cell LiPo's, balancing starts from the beginning. Balancing prevents putting 12 volts into a 4 volt cell, high pressure could cause an eruption.

As far as experiment, I have been comparing Energy Used (Infotainment) to SOC (Fuel % on left dash) by reconciling my home charge report to Energy Used. Here's my routine ... home for the day plug in L2 charger, if the SOC is less than 40% charging begins immediately up to 40% where charging stops and enters standby. Remaining charge begins when Target Charge Level can be achieved by Departure Time. In my picture for example, 60 kWh minus 51 kWh equals 9 kWh. 40 % SOC equals 24 kWh so in this illustration the charger will deliver 15 kWh's, plus some loss, or about 2 hours of charge immediately. Since I have been monitoring the Energy Used screen (over the last month at various Targets and consumptions), the math to 40% SOC has consistently worked out as well as the total kWh, compared to Energy Used, for the complete session at Departure Time.

The math that isn't consistently working out is SOC in real time.

Thank you each, these comments have been helpful.
 

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Balancing prevents putting 12 volts into a 4 volt cell, high pressure could cause an eruption.

The picture I posted is from a 100% SOC.

In my picture for example, 60 kWh minus 51 kWh equals 9 kWh.
Balancing a cell to 4 volts would never be done at 12 volts. That would be a pointless waste of energy requiring a huge bleed-off resistor. It would be done at 4 volts. The voltage difference between a cell, and a proper charger is a fraction of a volt at every point in the charge cycle. The reason for not sitting at 100% or 0%, for any length of time, is because of damage caused from stresses to the electrode coatings when filled or empty. At sensible 1C charge rates, tapering to near zero at the end, it is not the applied voltage causing most damage. In fact, the damage will occur even while sitting unplugged. Unlike hobby LiPo cells, GM never allows charging to 4.2 volt/100%. The highest voltage will be 4.19x. And at the low end they will tell you you are done at 3.2xx volts, which is much more conservative than the top. This is because, with top balancing, any difference in cell capacity shows up at the bottom of discharge.

I disagree with XJ12. Your energy screen and DIC pictures show that you have used 85% of a hypothetical, ideal 60 kWh battery. You should be seeing three bars. We can assume that the top bar is in fact about to disappear, so the bar gauge is saying you have 20.1% left. That still shows that your bar gauge is off by a full bar or 33% overly optimistic.

Did you let the charger shut down before you left, or did you pull the plug as soon as you saw 20 bars? Not waiting means you didn't get a full bars worth for that top bar. This could explain some of the error. If you did wait, GM has no excuse. Whatever the cause, this is unacceptable in an EV.

You can get SOC readings in smaller than 5% increments on the MyChevy phone app. But you have to keep refreshing it, which is a pain. There is no downside to running Torque Pro.

And yes, we are talking about tiny amounts of energy to drive a huge vehicle. Electromagnetic propulsion is incredibly efficient compared to blowing stuff up in a bucket, on the end of a crank. This is the only reason we can now have fairly practical king's carriages to ride around in on battery power. Enjoy it while it lasts.
 

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"Did you let the charger shut down before you left, or did you pull the plug as soon as you saw 20 bars? Not waiting means you didn't get a full bars worth for that top bar. This could explain some of the error. If you did wait, GM has no excuse. Whatever the cause, this is unacceptable in an EV."

I do enjoy this car very much and accept a "reasonable" tolerance in chemistry from battery to battery. It's interesting you're quoting cell voltage measure to the thousandths. With my hobby battery example the target voltage is set for the series but balanced at the cell level. I'm not sure how it's accomplished but from what I've seen cell internal resistance/chemistry plays a roll in the charge, discharge function top to bottom.

The charger is shut down, steady dash light, before I unplug.

The Chevy app appears to report SOC to 1%, good point.

You mention there is no downside to using Torque Pro.
I'm concerned to open a closed system. Is this more like peering through a window than entering the room?
 
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