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My Volt says uses only 10.3 KWh.... used to be 11.5

42K views 55 replies 34 participants last post by  Genecpu 
#1 ·
New to forum, sorry if this has been answered... I have a 2013 Volt. Pretty happy with it, it has almost 38K miles on it. Unfortunately I have noticed that the amount of miles I get from a battery charge seems to have gone down. As far as I recall the 2013 volt has a 11.5 KWh battery, and when I would look at the trip computer it would show the number of miles driven using battery and number miles driven using gas and show number of KWh use on the trip....

For most of the first year the battery would be 'empty' at 11.5 KWh used... This made sense.

Now a days though, I have used the entire battery and the computer reads that I have only used 10.3 KWh. So I was thinking that maybe the battery is degrading... So I think that's ok I have extended warranty.

But I called the volt advisor and they tell me that this is normal that the # of KWh used will go down based on driving behavior.

NOW THIS MAKES NO SENSE TO ME!! I told them I understand that if I am crazy/ fast driver that I will get less MILES out of a full charge. But if I am only getting 10.3 KWh out of a full charge I would think something is wrong.

So am I wrong?
 
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#2 ·
I think you are mistaken. You should never have gotten 11.5kWh out of the battery. More likely 10.5kWh.
This is pretty normal behavior for it to drop slightly. Most people have reported the same thing, and it stays at 10.3kWh for a long time.

Nothing to worry about.
 
#3 ·
Never heard of any Volt getting 11+ kW so it appears you may have mis-read your display.
 
#7 ·
Any electricity GAINED with regen is SUBTRACTED from your total kWh used.
 
#5 · (Edited)
As the others have noted , never heard of any Volt surpassing the 11 mark . The actual battery is 16.5Kwh , but only around 65% is used to promote longevity . This equates to around 10.5 Kwh . Every situation is different and 10.2-10.6 seems to be the normal displayed .
 
#9 ·
I have never seen 10kwh in my 2012 Volt...NEVER, but I can easily achieve high 40s all electric in good weather. Don't get caught up watching the kwh meter. It is kind of a guess to begin with instead of an actual measurement. I also believe the more efficient your drive the lower your numbers as you subtract from your KWH when braking and coasting. I enjoy watching my KWH meter run backwards, NOT Forward :) I have often seen low 9's with mine, 9.2 and as high as 9.8. I really couldn't care less what that thing says as long as my range is consistent (consistent with weather, terrain, driving style, climate usage). Range is highly dependent on those factors.
 
#11 · (Edited)
Based upon past discussions on this topic on the forum, it appears model years 2011 and 12 show KW used maximum in the high 9.x range, while MY 2013 owners get a maximum in the mid to upper 10.x range (.5KW more battery) and the MY 2014 owners get a maximum in the low 11.x range. Another observation from the forum is that MY 2013 and 14 although having different max KW used appear to have the same max range. My guess explanation for the variation in the MY 2013 and 14 is a change in the method of calcualtion. Bottom line, I agree, the OP probably misread or forgot the number from when the 2013 volt was new. 10.3 for a MY 2013 with 38k miles is good news to me.
 
#12 ·
I can easily get my car to show more EV range just by driving it, charging it a little but not all the way full and driving some more. I seem to recall seeing 10.6 when I first got the car, but I haven't checked the number since. When I run out of juice, the only number I'm honestly looking at is the mile range number.
 
#18 ·
That's some good garage insulation you have there then, ejk.
And I guess it is hard to argue with only using a bit more than 1/3 gallon of gas to go almost 50 miles.

As for the OP, in my 2013 I usually show 10.3 after fully depleting my battery.
 
#19 ·
What would be interesting would be to have a 2012 and 2014 Volt drive the same drive and see if they show the same kWh used and how far each goes on a full charge before switching to gas. The kWh used is just a software estimate so it could be the algorithm was changed, who knows?

I know in my 2012 Volt with 49,000 miles I can get about 9.8 kWh on a full charge, but I can "cheat" and boost that by 0.2 - 0.3 kWh by overcharging the battery before I leave.
 
#21 ·
Just to add this into the mix. My (late 2012) Volt not infrequently displays a total use in excess of 11kWh and on at least one occasion more than 12kWh. I don't for one moment believe that is accurate: I've seen that sometimes toward the end of the range the total power used climbs very rapidly, so it can appear to use a couple of kWh in a mile or so. Also sometimes the total power used is as low as 8.8kWh.

Chevrolet took my Volt away for a couple of months and tested it thoroughly but concluded they couldn't find anything wrong.

I believe the problem is with the estimate of energy used (it is only an estimate,I understand the Volt doesn't measure it directly). So far as I can tell I get a perfectly normal range and though I do get PPR quite often after the battery has depleted that happens no matter whether the recorded energy used was 8.8 or 12kWh.
 
#24 ·
Use OBD
Total kWh used divided by (starting SOC%-ending SOC%)
(From a full charge without using gas)

Or next time you're at a dealer, ask for a capacity report, apparently there's a test printout you can get (another member here has posted his)
 
#25 · (Edited)
??? What are you talking about? Capacity test report?
I assure there is no such thing
There are a couple PIDs that can be useful in extrapolate a guesstimate from but...
But those values are really unrelated to the instrumented observed kWh value on the center stack which (as we keep reminding people) is essentially meaningless
WOT
 
#29 ·
Thanks for clarifying. Perhaps test was the wrong word on my part, but rather reading.
It sounds like its more of a battery systems self-test/diagnostic/monitoring, which is pretty much as expected. The dealer doesn't "test", but rather retrieves test results.

In the context of what was asked, though, this is pretty much the answer.
It's not that much of an issue of it being exact or a hard value, but rather if the computer thinks it has a battery capacity of x (based on its own calculations), then that's the value the end user is interested in.
If you have a 17 battery, but the computer thinks its 16.5 based on measurements/calculations, then obviously it should be performing like a 16.5, and that's all the end user probably cares about.
Nor is it of much importance whether that value is 16.4 or 16.6, but you'd know the general ballpark of where it stands - either the 16.5 camp or the 17.1 camp.
 
#30 · (Edited)
Again. This capacity PID simply cannot be "interpreted" as you are stating
As such it cannot be utilized as it is meaningless as a SOH value and essentially useless to an "end-user" as a performance metric
The actual battery SOH routines run in the background and will trigger hard DTCs once critical thresholds achieved or exceeded
WOT
 
#33 ·
In my 2012 Volt it is incredibly reliable. I was getting 9.9 kWh on a full charge new and just about the same amount 3 years and 65K EV miles later. What I find useful is to see what the kWh used display shows when each 10% bar drops. Each additional bar is almost exactly 1.0 kWh apart. So one can figure exactly how far they can go until their range is depleted. This is much more accurate than the battery miles estimate. I've used this technique to go gas free for the last 56,000+ consecutive miles.
 
#35 · (Edited)
My 2012 w/21,000 miles today got 37.0 EV miles @ 10.7kw.. the usual is less than 10{may have hit 10kw once before} but then again; I've been getting exceptional ev since my diagnostics's quit communicating with Onstar about 6 weeks ago. getting at least 5 more ev miles since this event! 36-43 Electric miles best ever before was 34!!!!!!!!!!
 
#36 · (Edited)
My 2012 w/21,000 miles today got 37.0 EV miles @ 10.7kw.. the usual is less than 10{may have hit 10kw once before} but then again; I've been getting exceptional ev since my diagnostics's quit communicating with Onstar about 6 weeks ago. getting at least 5 more ev miles since this event!
There's absolutely no relationship between OnStar and your powertrain efficiency. lol
Maybe check your biorhythms or maybe moon phases! ;)
WOT
 
#37 · (Edited)
So, how else would you explain it? It seems to be a computer glitch....
There is no other explanation except for the recall flash {to turn off volt if left on} and I hope that is the reason for my increase!
What else could cause it getting 5-7 more ev miles and now .7 kw more than the entire year and 1/2 of ownership of a new volt?
It is not necessarily OnStar per se but the diagnostics not being readable by Remotelink nor Onstar, which was caused by an Error message they couldn't reset nor read, for a remote battery[which finally disappeared after a week ]! However:We do get the Miles though on Both!
We have the new mirrors and Goodyear gave us new Eagle Sport tires not the Low rolling Resistance tires!
 

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#38 ·
What else could cause ... .7 kw more than the entire year
I guess my post above slipped by you. The kWh diplayed can't be relied on. It's not a meter, it's an estimate.
 
#40 ·
This is one of those things that sometimes needs to be explained in different ways to get you to the "ah-ha" moment of understanding why this number fluctuates. I had the same concern when I first got my Volt and I remember being absolutely certain that my battery capacity was shrinking, only to later realize I was mistaken.

The kWh used number is an estimate, just as the experts have already explained. If the core of the question is "why does the (estimated, imprecise) number sometimes trend up or down?", here's another way of looking at it:

The confusion may be rooted on a bad assumption that the car "uses up the battery" to a constant low-water mark before the gas engine comes on. It doesn't work that way. Even if the kWh gauge was highly accurate (which it isn't), it would be wrong to expect the same number every day. In my 2013 Volt I've seen the estimate range between 9.7-11.6.

Why? One reason is that the gas engine works with a reserve (or buffer) of energy in the battery after the electric range shows 0. When the battery is near the bottom of the buffer the engine works harder to bring the charge up. Likewise, when the battery accumulates more energy from regeneration, the engine shuts off. This happens behind the scenes after the icon flips from battery to gas on the dash.

The Volt tries to protect the battery and maximize efficiency. It also tries to keep you out of propulsion power reduced mode (drawing too deep into the battery reserve before the ICE can catch up). It estimates the best time to switch to gas based on several factors, including how much more power are likely to pull from the battery during the ICE warm-up. If the power draw is high (due to driving style, climate control, battery thermal management, terrain, temperature, etc.) it may cut over sooner (~9.6-~10.3) than if it predicts you'll just be sipping electrons (~10.6+). That is also one reason why you might notice the "last 1 mile" of electric range is sometimes significantly shorter than a mile and other times it is longer.

My point is that the cut-over point from battery to ICE is designed to vary and the kwh number, like the range estimate, is fuzzy.
 
#41 ·
That explains the down shift, yes, but not the shift upwards that you seemingly get more power than allowed from the battery (no more than 65%)
And that one seems to be due to changes in elevation and regen overcharging.

That, or OnStar has been hogging 700Wh this entire time. Bastards.
 
#44 ·
LOL the telematics company has nothing to do with it. Everyone has read something into a malfunctioning car which results in it getting the Ev miles it was promised to be but never was! When the charge door stuck numerous times, before I wiped silicone on the rubber and stem; it set off a Red Check Engine light. Called OnStar, they informed me it was the charge door error and the lights never come on again! The Remote Battery Light would not go out after replacing that; so I hit the button but neither they nor the Technical department could read the car. So I'd have to go to Dealer to get the light turned off and my Diagnostics reconnecting. Alas, I remembered the day before replacing the battery I got 40 miles on a charge! That is 4 more miles than the volt ever got. A week later the light continued to boost my EV all the way to 43.1 Ev miles. So I don't want it fixed and the light finally went out a week later.
Monthly emails were fairly normal until Sept(no august email) when I received two 6 days apart and both had Exclamation marks{!} under all the Diagnostics where there used to be Checks{no symbol on keyboard}, then 2 days ago the same for Oct !!!!!!!! Marks
SO WHY DOESN'T EVERYONE DO SOMETHING CONSTRUCTIVE like demand General Motors do software updates to make the most of the batteries limited resources and all the prospective year Vehicles get the same Ev MILES that they provided to the EPA, sales, marketing and Us[the CUSTOMERS] I know how to drive efficiently(had a Prius and still a 40mpg Escape AWD hybrid) and when I do, the Volt doesn't reflect That in it's performance that was promised to me and many others I've read about on all forums and reviews (and I do research on everything I want or own to a point) but have kind of thrown my hands up and given up on my Volts expectations(until now that it's broke). Chevrolet has left us high and dry with no more simple flash fixes(didn't Toyota do them?)(they have the information and the resources);which is probably why they gave us so many years of free OnStar to begin with! To use all of the information via Yes OnStar........
 
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