[hroussel]

Hello,

I have a 2013 Volt. Doing mostly city driving, very few highway trips (maybe 15) where I used all the capacity, falling back on the ICE. The usable kwh was around 10.3 (sometimes 10.4) kwh when brand new.

Since last summer it started going down. I noticed that whereas previously one green bar was roughly 1kwh, now the bars go down more quickly. I usually get 9.3 to 9.5 kwh max from the battery. Is this normal? What are other people's experience with their Volt?

Thanks

 

[Steverino]

See the "kWh Used FAQ. Does it measure Battery Degradation? Reliability?" at http://gm-volt.com/forum/showthread...y-Charging-amp-Battery-Managment-System-FAQ-s

In short, it's not a meter, it's not measuring. It's an estimator.

 

[2VoltFamily]

Well on 2013 (could be others) there was a firmware update that caused this issue. You may want to search the forum cause I don't remember what it was at the moment. But it did happen to me and some others.

 

[BAZINGA]

Have you discharged the battery fully (to cause the ICE to run) and then fully charged it back up? Often that can help reset the meter to reflect a more accurate number. At least that was my experience on my 2012/2013 when I drove for weeks on the battery never fully discharging it.

 

[ampera_jed]

It does seem to give a bit less in winter.

If you do have degradation, it would be the first in 100,000 cars, to anyone's knowledge. I guess someone has to be first, but there are plenty of Volts out there with both more mileage and older too that have no such issue.

The manner of your drive will also change what appears on the screen. As mentioned, it is an inferred calculation, not a measurement. If you do a lot of regen it tends to read high, and if you do a lot of heavy footed highway then it reads low.

What counts is how far you get on EV. Sounds like most of the time you aren't using the whole battery, and only occasionally draw it low on the highway (i.e will probably read a little low). If you routinely use up the whole battery it is easier to see the mileage consistency.

 

[ari_c]

I've basically gone years without fully discharging my battery to the point where it switches to gas. I see no difference. However, there is one thing that can lead to a lower kWh used number and that is a cold battery. If I drive off with a cold battery, I can sometimes see my first bar drop sometimes from 0.5-0.7 kWh.

Warming up the battery first solves this problem. If you have L2, just turn on the Volt (climate off) with it still plugged in a few hours after a charge completeed. It will continue to charge. Let it charge up until charging completes, unplug and drive off. It should charge for up to 20 minutes. The colder it is, the longer this secondary charge will last. Try that and let me know if you see an improvement.

As a bonus exercise, unplug right before charging completes and you can get an addition 2-3% SOC. If you have ELM327 OBDII, charging completes about 1-2 minutes after charging amps drops to 5.0A.

 

[telveer]

Gen 1 Volts don't show other usge (hvac, conditioning, etc)... just traction usage. Other usage could be significant, especially in bad/cold weather. So, just checking the kWh used from the center screen is not a sure way to determine battery degradation, or lack thereof.

On a good spring day, with temps between 65F-70F, run the battery down fully a few times and see what you get. On my 2013 with 36,000 miles, I still get ~ 10.4kWh in ideal conditions. However, even this may not provide the full picture, as the meter is not super accurate.

If you strongly suspect that something is wrong with your battery, the best way to ascertain that is to get a full blown test done by a qualified Chevy volt service center.

 

[ClarksonCote]

It does seem to give a bit less in winter.

This, and the kWh used is an estimate. Wait until summer and see if it returns to the 10.3-type numbers.

Your driving patterns can also affect it. Pulling more kW driving at 80 will cause the battery to declare itself drained earlier than when driving at 20. It has to do with voltage droop.

 

[ctiomico2003]

I was about to ask the same question about my wife's Volt and I am glad that someone else asked.

Due to her short work commute she is not discharging the battery in full and only uses about half a battery a day and then gets refilled in the morning before she leaves.

My Volt gets a full discharge everyday and I maintain around the 10 kWh "estimated" discharge with 30 - 40 miles.

We discharged her battery fully last night and she got 36 miles for 9.3 kWh. So in the end, it was about the same range with just a different result for kWh use estimation.

Thanks for posting the links!

 

[ari_c]

Do you do anything differently than she does with the Volt before leaving? Does she preheat the car or remote start?

 

[ctiomico2003]

Living in SoCal, there generally isn't a need for us to preheat or remote start the engine.

I think the short drive vs the long drive and fully discharging vs not doing so were the biggest factors.

But since mileage is relatively unaffected, I am not as concerned.

 

[NRA Life Member]

I use the MyGreenVolt app to keep track of my energy usesage as I drive. That way I can see pretty well where the energy is going. My 2012 with 71,000 miles typically gets 9.6kWh of use and the mileage varies with temperature and other conditions. My low was 20 miles in 14degrees F and I had a high of 49 miles in the summer with a slight tailwind. This winter my "typical miles" are mid to low 30's. In the fall when temps were in the 70's, I would routinely get 40 miles per charge. Almost everytime, my Volt changes from Battery to ICE at 9.6kWh. On rare occasion I've seen 9.8 and as low as 9.4kWh. My ICE mileage typically runs low 40's MPG at the sweet spot of 68mph.

 

[canehdian]

Gen 1 Volts don't show other usge (hvac, conditioning, etc)... just traction usage. Other usage could be significant, especially in bad/cold weather. So, just checking the kWh used from the center screen is not a sure way to determine battery degradation, or lack thereof.

All energy used by the vehicle is reflected in the kWh used number. This includes cabin heat, battery heat, AC, headlights, what have you.

The only thing gen1 doesn't do is show you a breakdown line by line, which gen2 does.

What a lower number tells you is that the battery was likely cold when depleted - the computer saw a low energy level and switched to gas early. Had the battery been warmer when you were at the bottom, you likely would have gone a little further before battery dipped low enough to warrant engine-on.
If you park your car at -20 outside on a driveway and record the SOC, then drive 5 seconds inside a heated garage and check it hours later, your SOC will have shot up a large chunk with no charging taking place - this is the extra energy that was likely "lost" by OP (if not the aforementioned firmware issue).

As you said, a spring/summer day you will likely see business as usual.

 

[Dakster]

Big difference with temps in the Volt. We were not hyper milers, unlike ari_c who BTW, I give a lot of credit too. I want him to work his magic on a Bolt amd break 350 miles on a full charge. Anyways, FWIW, in Florida, we could get 48 miles on a full charge, in Alaska that dropped to 22 miles in the winter and I am even suspect that it would really go 22 miles on a charge since I had a lot of ERDTT use. Now in addition to temp were the fact we needed studded tires, last year we had our volt I ran around in the summer with the studs removed from the tires and best I could get was 33 on a full charge vs. 38 up here on the OEM tires... In AK, it's home was in a heated garage (well, heated to +40F).

 

[ari_c]

We were not hyper milers, unlike ari_c who BTW, I give a lot of credit too. I want him to work his magic on a Bolt amd break 350 miles on a full charge.

If I do get my hands on a Bolt, I project I can get somewhere between 480-500 miles on one charge.

 

[hroussel]

Have you discharged the battery fully (to cause the ICE to run) and then fully charged it back up? Often that can help reset the meter to reflect a more accurate number. At least that was my experience on my 2012/2013 when I drove for weeks on the battery never fully discharging it.

Not recently. Being in the winter also doesn't help. I'll have to try again when summer comes.

 

[canehdian]

If I do get my hands on a Bolt, I project I can get somewhere between 480-500 miles on one charge.

21h marathon in Ari's future? (assuming the magic 24mph applies to bolt as well as volt)

Not recently. Being in the winter also doesn't help. I'll have to try again when summer comes.

Winter is the easiest time of year to reset it as you often are running near empty because of cabin heat (at least more likely than summer).
Just run it down to gas pump icon switchover (engine doesn't have to actually start), then turn off the car and leave it unplugged for ~2h.
Then wake the car up and plug in to charge.
Repeat for the next few charges to help it re-learn.

 

[llninja]

If I do get my hands on a Bolt, I project I can get somewhere between 480-500 miles on one charge.

Driving a Bolt in circles around a parking lot for 10+ hours isn't my idea of fun. But in the interest of science....

 

[VoltenRock]

Because you have a '13, you need to make sure you did not get a corrupted update if you brought your '13 in for ANY dealer service that may involved resetting HPCM#2. See my saga on this thread: http://gm-volt.com/forum/showthread.php?198114-Going-to-dealer-any-ideas-on-my-Volt-s-strange-issues

In MY particular circumstance, the sudden drop in the kWh used ESTIMATOR was revealing an actual problem. The correction is following the procedures in bulletin PIC6138A.

 

[hroussel]

I use the MyGreenVolt app to keep track of my energy usesage as I drive. That way I can see pretty well where the energy is going. My 2012 with 71,000 miles typically gets 9.6kWh of use and the mileage varies with temperature and other conditions. My low was 20 miles in 14degrees F and I had a high of 49 miles in the summer with a slight tailwind. This winter my "typical miles" are mid to low 30's. In the fall when temps were in the 70's, I would routinely get 40 miles per charge. Almost everytime, my Volt changes from Battery to ICE at 9.6kWh. On rare occasion I've seen 9.8 and as low as 9.4kWh. My ICE mileage typically runs low 40's MPG at the sweet spot of 68mph.

That sounds close to what I currently get for battery capacity, so maybe it's ok for now. I'll wait for the summer to come back as right now my mileage is extremely low with the cold weather (as in 14 miles before the ICE starts and I've used my 9.x kwh of battery).