At What Point Does Chevy Volt Battery Show Signs of Range Loss?

JUN 18 2014 BY MARK HOVIS 54

2012 Chevy Volt

2012 Chevy Volt

Chevy Volt Battery Pack

Chevy Volt Battery Pack

At what point will the Chevy Volt show signs of range loss?

This has been a question for some time in the EV community. General Motors made a bold and brave move to limit access to the Volt’s 16.5kWh battery to around 10kWh. The brilliance of this move both protected the battery from overcharging and left Volt drivers with the same driving experience with zero loss of range for years of ownership.

Few remember, but it was GM’s design that forced Nissan and Tesla  to provide the eight year 100,000 mile battery warranty that has set the standard for the industry.

Editor’s Note: Due to a communication breakdown this article was posted prior to finishing the test. Will update in the near future.

Most Volt owners sit back and listen to stories of range loss with other brands with a large grin on their face knowing they have yet to experience it. As stated before, it is primarily in the protected design that has hidden this natural chemistry degradation from our sight. With over 60,000 Volts and a half a billion miles, it is only a matter of time. Chemistry still is chemistry.

97,000 Mile 2012 Chevy Volt

Recently, I came upon a 2012 Volt in good condition with  97,000 miles for $14,000 that I just couldn’t pass up. I secured the used Volt for my younger brother but not without some basic testing and comparison to my own 2012 Volt with one fourth the miles. This Volt was a fleet vehicle in Florida averaging over 40,000 miles per year. My Volt is pampered and kept in a shaded garage. Though the conditions of the fleet vehicle cannot be known, the Florida temperatures are not as tough as Phoenix but hotter than my North Carolina Volt.

Chevy Volt

Chevy Volt

With the 97,000 miles driven on this MY2012 Volt, it is clear that many, if not the majority of the miles, were using the gasoline powered range extender. My hypothesis was that the battery should not suffer due to the excess ICE miles. My curiosity was now to find out.

When I received the Volt the guess-0-meter registered 35 miles of total range. I took the Volt out on an easy drive averaging 48 mph. It achieved 45 miles of AER all electric  range. The number is relative to many factors, but comparing to my well cared for Volt, I achieved 50 AER on the same path and similar conditions. The first test showed 10.3 kWh used.

Another interesting discovery was that the charge took nine hours opposed to the typical eight on my Level 1 charger.

Bottom Line

If you have ever seen the movie “Black Beauty,” there is also no telling how hard this horse has been ridden. Still this 97,350 mile Volt is “not” showing any changes in the intended driving experience. Though degradation occurs in all batteries, it happens at a lesser rate when the charge is limited and  thermal conditions are managed. Bottom line, the AER driving experience has not changed past the GM specifications.

Many naysayers wait with baited breath for EV battery replacements. With high mileage EREVs like the Chevy Volt, they will have to wait a bit longer. At some point the Chevy Volt may give up 4-8 miles of AER at 98 MPGe, but will continue on its extender for many, many miles to come.

I plan on doing a bit more tests prior to turning it over to my brother. If you have any tests you would like to see, then leave a detailed comment below.

Categories: Charging, Chevrolet

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54 Comments on "At What Point Does Chevy Volt Battery Show Signs of Range Loss?"

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When I owned my Leaf, I was astonished to see the lengths Nissan went to in order to hide battery conditions from the driver. “Bars”, “trees”, etc but no accurate and precise capacity or state of charge information. I know little of Volts, but it seems they suffer the same obscurification.

Hi McKemie,

They do, sort of. The Volt doesn’t have a read out of battery percentage, but it has 10 bars, each of which represents 10% of the capacity. As I understand it, that is unlike the Leaf, where 3 out of 12 bars does not mean 25%, and actually means MORE than that.

The Volt also has an kWh used estimate that is fairly accurate. Knowing the usable kWh of the battery, the kWh used can give a reasonable percentage of used capacity if one wants to calculate it. It maps well to the green bars.

I also seem to recall that the most recent model Leaf does have an exact percentage read out.

Lou Perez

IMO there is too much made of the battery life issue. Federal law requires the battery to maintain 70% of charge after 8 years or 100K miles. In CA, it is 10 years or 150K miles. If the battery has less than 70%, you get a replacement (likely reconditioned) one.

Do ICE owners get new engines after 8 years if their engines don’t pass a compression test? Don’t think so …


Although I applaud you for finding a great deal, your test only proves that the two Volts had different AERs (well within the range stated by GM on the window sticker).

It does not prove battery degradation.

Hi Mark, thanks for the write-up. I would be careful to conclude that the Volt is showing any signs of battery loss based on a 2 mile AER difference on the road and on the range estimate.

The former can be due to many factors that are outside driver control. A 2 mile difference doesn’t seem enough to conclude that there is battery loss, and is within the error bounds of condition variations.

Additionally, the 2 mile difference in estimates can simply be due to the Volt still needing to adjust to its new driving patterns following the 96,000 miles of fleet driving.

The main reason why I’m skeptical is because I suspect a lot of gas miles would actually be nicer to a battery than a lot of electric miles. That means less charge cycles which is the real driver in capacity loss.

The battery may need to be cycled a few times from full to empty to help balance the cells, but otherwise this battery should otherwise be in better shape than another battery having more electric miles, but less miles overall. 🙂

Curious to hear any updates as time goes on!


A few things wrong overall with this story. It was published after just one day’s testing. Were all things equal? Tire pressure is one key, did the 2012 have suitable tire pressure? Also, the battery needs a few full cycle charges to best balance the cells. I have to believe that you will see it produce nearly the same range if you run a few charges through it and you keep the tires at the same level as your other Volt.

David S.

Differences in tire wear and brand/model can also have an influence.

Mark H

It wasn’t ready for posting. Eric, I thought pending was the signal for release.

Ah. Maybe Eric Loveday will work with you to send out an “updated” story?


This is exactly correct and IMO the author is simply “blowing smoke”. There are cars with much greater EV miles that are not showing ANY discernible loss in AER.-WOT

Lou Perez

Why didn’t the author just take the car to a Chevy dealer and ask them to do a battery test? They have to have battery diagnostic software .


Battery capacities are also not identical from car to car even at day one. Also, later model 2012’s had the larger AER charge window of the 2013’s. You should compare the VIN’s. Watch the full charge estimate. I don’t think only one cycle fully recalibrate a to the current conditions. Did they reset the trip meters? Maybe they can give a good idea of how many miles were AER and RE.

Mr. M

“With the 97,000 miles driven on this MY2012 Volt, it is clear that many, if not the majority of the miles, were using the gasoline powered range extender. ”

I don’t understand how you come to that conclusion.

If I understand the american market correctly the MY2012 can be bougth already during Mid of 2011. This means the Volt migth be three years old. With ~220 Workdays each year and recharging at workplace (twice a day 40 miles AER), this can cumulate to 660*2*40 = 52800 miles in electric mode. Conclusion: I would not say that the Range Extender made the mayority in miles…

Is there solution how to find out how much miles where really electric only?

Mark may have connected to OnStar through RemoteLink. (Thomas Thias reported recently that second owners can press the OnStar button and get the remainder of free service.) This would report total miles and EV miles. Or, the lifetime MPG on the vehicle may be very low, indicating lots of gas miles.

Thomas J. Thias
99% of the Chevy Volt Extended Range Electric Vehicles on the road today under 1st owner or multiple 2nd or 3rd owners still have FREE OnStar with directions/Conections; Navigation on Demand Service, Teltmatics Phone Service; buy minutes as you go and smart phone app for remote start, door unlock and sound horn plus much more. Here is the FREE coverage breakdown. -Model Year 2011, 5 years Free from new. -Model Years 2012, 2013 and 2014, 3 years Free from New. To activate have the Volt on, in park, radio on and radio volume,up. Plus the Blue OnStar Button, NO NOT THE BLUE VOLT START/STOP BUTTON, LOL… Push the OnStar Blue Button on the ceiling of your Volt. Tell the attendent that you want to activate the remaining ballance of the FREE OnStar service. They will be happy to do so. They will want to sell you phone minutes(Each OnStar Vehicle Has Its Own Unique Phone Number), they might want you to sign up for a longer term, they might offer more enhanced OnStar services for a fee and ask for a credit card. OnStar has many outstanding features BUT If your just activating the ballance of time in your name,… Read more »

One thing that I have noticed on my Volt over the past 3 years has been the choice in tires as well as wheel alignment. When I first got my Volt, I was able to get 50+ miles all electric when I was very careful; however, I noticed awful wear patterns on the tires after several thousand miles. After getting it aligned, I have struggled to get more than 42 miles. The same thing happened to a friend’s Volt too.

I would say that if both have proper alignment and the same tires and wear, that would be a closer-to-true comparison.

David Murray

This was not a very scientific test. I’m not even sure such a proper test exists. But the closest thing would be to drive both volts until the range extender comes on and compare the amount of kWh that was used.

I suppose another test would be to drain both Volts completely, then use a “kill-a-watt” or similar instrument for reading the amount of energy from the wall required to fully recharge. Make sure both cars are done at the same time in same temperature conditions.

Dave R

Yep, running each car through say 3 measurements of the energy required to recharge from empty to full while also noting achieved EV range is probably the best one can do without pulling the battery and testing it directly.

Benjamin Anderson

Some questions were the tires the same and were were the model years the same. 2013 and newer have slightly larger battery packs. More info is necessary to make a fair comparison.


Actually the larger available charge window started with late 2012 models.


Read this, it might just apply to your Volt. You just need to nurse the battery back to life with a few full cycles of discharge / charge….

Mark hi, Thanks for this nice piece of “citizen research”. IMHO on the engineered battery bounds is yet another example for GM’s entire Volt story: great engineering, lousy job getting inside the customer/driver’s head, even worse job marketing. Yeah, the positive angle on this “you get to use 10KWh only” is that it all but guarantees a very long battery-pack life. But is GM trying to make any money (i.e., sales) off of the Volt’s stellar reliability? Or is it a secret shared only between aficionados and those who closely follow the auto industry press? So what’s the point here, esp. that the general press still says the Volt is a waste of money and a failure? Now… to the driver. The battery-protective bounds mean that while you *paid* for a battery-pack that could in principle give you ~60 miles EPA range (with some $$ help from the government, yes), GM had decided you can use only <40 miles of that range. The rest is being carried around, day in day out, like dead weight – for what purpose only God knows (since GM has yet to capitalize on this over-engineering in any meaningful way). First, this indicates a huge… Read more »

I think “paternalism” is an unfair characterization. My instincts are that the Volt was an engineering driven car with little marketing input (they were all off working on the higher volume cars, I suppose). As such, engineers strive to be conservative in their designs to make sure that the product performs reliably. So, underutilizing the battery capacity could simply just be an engineering decision. Plus, this was brand new territory for GM so it’s not surprising that they opted for a conservative approach. As such, they built a car that has proven itself to be reliable. And with that, the customers have shown strong satisfaction with the volt. Paternalism? I think not. More like solid engineering.

“But is GM trying to make any money (i.e., sales) off of the Volt’s stellar reliability? Or is it a secret shared only between aficionados and those who closely follow the auto industry press? So what’s the point here, esp. that the general press still says the Volt is a waste of money and a failure?”
After a couple years Nissan was being sued by its customers for sh!tty battery life, how does that help sales? Let’s see what the market says 10 years from now when GM cars are still driving around w/their full range and the Leafs have all been retired or sold for peanuts because the batteries degraded so much.

Not sure what media you are ingesting(Fox News?), but most give the Volt great reviews. I won’t even list the awards.


I’m sorry you are reading a “Leaf vs. Volt wars” into my comment. That’s 180 degrees opposite my intention.

From a marketing perspective, a two-digit EPA range that starts with a “3” sends a message of “gas car with some EV capabilities”. The fact many people don’t drive more than that in a day is moot compared with this overwhelming impression.

If you built a battery that’s only that big, it’s one thing. But to have such a large battery and use so little of it, is a marketing and consumer-orientation failure IMHO.

Unless it pays of when your cars our outlasting the competition and you don’t have to pay for warranty issues.

The thing is, every product has its strengths, weaknesses and limitations.

Nissan seems to be learning pretty well from its early Leaf mistakes.

OTOH, so far GM has only been digging newer and deeper holes for itself (laying off the Volt as a leading EV brand, sitting on the Spark as a compliance car, the ridiculous bet on the ELR, etc.).

Maybe GM will shock us all in 2015 and 2016 with an amazing EV marketing strategy – I will be happy if that happens! – but that’s not what it has done so far. A

nd yes, I do see keeping 40% of the Volt battery off-limits to drivers, as part of the same pattern. Nothing you or others have wrote, provides substantial evidence to the contrary.



I have seen plenty of your posts and most of them are just “GM/Volt hating” post tones which basically traces back to your issue with GM EV-1 program.

With that said, how much has Nissan done to its LEAF? Nissan dropped price on the LEAF. GM dropped price on the Volt. Nissan make the LEAF worse in safety (from 2011/2012 to 2013/2014) from 5 stars to 4 stars. Volt stayed the same. Nissan made the 2013 or later LEAF slightly more efficient and longer range. GM did the same with the Volt by 3 miles (which is about 9%).

Sure, there is a lot to improve on the Volt, but you just sound like a whiner…


Also, you can’t do math.

37.5% is the buffer. But you forgot to include the “regen” buffer on top and battery drain buffer at the end.

“GM had decided you can use only <40 miles of that range. The rest is being carried around, day in day out, like dead weight"
This distance was determined to cover 80% of all driving. What about the Leaf? It carries around much more "dead weight" when the driver is only commuting 25 miles/day. I don't follow this logic.

“Even though they pretty clearly have no clue how to play the EV game. I much prefer Nissan’s and Tesla’s blase approach to their BEVs’ capacity: this is 1st generation, just take it and explore the limitations, and know it won’t be as predictable as a Toyota Camry.”
It’s not a game, and its not particular to EVs. Its called running an auto-company and GM has been doing it for 100 years. You need to make reliable products, plain and simple. You can sell crap, and try and clean up the mess later, especially when it’s new technology with a big magnifying glass on it. You prefer Nissan’s/Tesla’s approach of just testing in the real-world after production? That’s nuts. GM did accelerated lab testing for years and continues to do so, before they sold the first Volt.

What happened to GM 80 years ago or 50 years ago is immaterial.

GM needed a bailout 5 years ago. It went bankrupt due to *very* poor decision making and warped priorities.

The mindset that has bankrupted it, is the same mindset that killed the E.V.1. Judging from GM’s current EV strategy – that mindset is unfortunately still alive and well.


If GM did EV1 as you would like, it would still have gone bankrupt.

It is just stupid to think EV-1 like cars would have saved GM…

Thomas J. Thias

No Assaf, Gm, Christler and Ford were pushed to the edge or into structured bankrupcy by an intense liquidity run caused by a spike in the cost of a gallon of gas to a $4.00 average from early June througe late October, 2008.

Link Goes To Gas Buddy dot com- Retail Gasoline Price Chart- Average,,&Unit=US $/G

This Licquidity runcame on top of the now forgotten collapse of Global Finincials and an implosion of the world banking system.

This spike in fuel costs destroyed the residual values of hundreds of thousands of Light Duty Trucks, Vans and Sport Utility Vehicles leased out in 2005/2006.

Gm/GMAC/US/Canada, Ford Motor Company Credit And Chrysler Financial became exposed to the immediate prospect of covering these losses on a vehicle to vehicle basis with no end in sight.

Retired Ford CEO Allen Mulally cites the need for government intervention as a total liquidation of GM and Chrysler would of taken down Ford as well ant thrown the country into depression.

Link Goes To LA Times Report from April 19,2012.

The cost of a gallon of gas had crashed to the $2 dollar mark by late november of 2008 the mortal financial damage had been done.


Thomas J. Thias


Thomas J. Thias

The Gas Buddy dot com 96 month average retail gas price-

Link Again Goes To Gas Buddy 2008 Gas Price Spike Chart- Average,,&Unit=US $/G


Thomas J. Thias

Heh, posting this Gas Buddy dot com 96 month retail gas price chart has been interesting!
Here if is, I promise!

Linked In From Twitter Photo=

Sorry bout that-

Thomas J. Thias

Mark: The Energy Info screen on my 2014 Volt says I’ve used 10.9kWh-11.0kWh (it varies) after I have I run the battery from fully charged to the point where the range extender kicks in. What does your brother’s 2012 Volt show?

Mark H

The first test produced 10.3 kWh. Not expecting to see it change. No real way to see the reserved portion’s degradation. Still testing.


You first need to establish if either Volt was produced in June of 2012 with the larger battery. Assuming they have the same size battery, they’d need the same tires and similar tread depth left. Finding out how many miles in EV mode from onstar is important to know as well. Since the usable KWh window would shrink over time, rather than be expanded, charging both volts under the same conditions and measuring the total draw for each will give you each Volt’s usable KWh window….

I don’t think the usable kWh window will be equal to the total draw from the wall…. Due to charger inefficiencies, total draw will be more than energy stored in the battery, correct?


Yes, one volt might draw 13.2 KWh while the other draws 12.8 KWh…..

Thomas J. Thias

Hi Czar,

You said.”Assuming they have the same size battery~”

Ouch, while we all know what you meant, the reader, new to this forum, trying to learn, might begin to ask about different physical sized, Volt EREV Traction Batteries.

The reference is to, some late model 2012s and all 2013, 2014 MY Chevy Volt EREV’s with the Enhanced Battery pack.

Forgive me if I’m splitting hairs with you but as you know even us seasoned Voltec players learn more every day!

My Very best, Czar,

Keep The Tweets and Videos coming!

Thomas J. Thias


Mark, maybe you can see if you can contact this guy and ask him how his range is.
(from Voltstats)
Serial # 2011-00338
Name: Joe’s Volt
State: CT
EV Miles: 63643.90
Total Miles: 82823.24
EV%: 76.8%
MPG: 169.13

Thomas J. Thias
Kdawg- This Assaf Fellow last caught my attention on these pages back on May 11th, 2014. Looks as though you missed this post by Assaf as I did not see a comment from you. I finally had enough and weighed in. My comments to this assaf fellow are repeated below from May 11, 2014 at 8:17 pm. Link To InsideEv follows contents of my comments. —————— Thomas J. Thias May 11, 2014 at 8:17 pm The Electric Fueled Vehicle Marketer has entered the arena! Thank You Mr. Assaf for your contribution today. However, an undertone of your piece echoes many an Electric Fueled Vehicle Industry critic’s baseline arguement. As you innocently and naively state in your opening: “[…]Nowadays it seems that every automaker who seriously puts their mind to it, produces an EV that wins awards and accolades that *can* become a jewel in its crown if it so wishes (GM, are you listening?). So… why haven’t EVs become more popular earlier? And why are they still just barely coming out of the fringe in most countries, and still on the fringe in many others? Well, the nature of human society is that Technology B being objectively better than Technology… Read more »
Blind Guy

We recently took a 2500 mile trip; Tucson-San Antonio, Rock Port, Houston, DFW-Tucson in our 2013 Volt. Starting AER was 43, we used MM and HOLD mode several times and was only able to charge once due to opportunity and 3 chargers in Cedar Hill not working. After charging back at home, we had 37 AER. We cycled the battery 1 time fully and had 39 AER. I am confident we will eventually get above 40 again despite using comfort for the summer. Since we bought the Volt, we have always gotten above the 38 EPA AER except for 2 times :D. 22500 miles, 100 lifetime mpg (with several long trips using mostly gas). 129 lifetime mpg before latest long trip.


Good article Mark.
I applaud you for this somewhat pioneering effort in purchasing a used Volt with 97K miles for 14,000 dollars.

From the sound of it, it is well within the AER of your pampered Volt. With essentially no degradation. Truly a value proposition for sure.

Hopefully we will have another follow up article after you have had more time to investigate and test further.

Evil Attorney

Has anyone from GM clarified with certainty what happens to the window of usable battery as degradation occurs? Do both the usable and non-usable percentages of battery shrink, or does the Volt “hide” degradation by always providing about 10kWh of usable battery?

In any case, if the Volt’s battery degradation is performing that much better than the Leaf or even a Tesla, GM needs to brag about this. It’s a very important factor for anyone buying a car with a battery in it.


@evil attorney. The question has been posted and discussed on the gm-volt forum. The consensus is the usable window shrinks as the total battery degrades. Andrew Farrah from GM has said to expect a 10-30% range loss after about 9 years..,,,,


It is more than a consensus. WOPONTOUR has said so.
But I do not understand this design and still maintain a hope that WOPONTOUR got this one wrong… despite the fact that he has been extremely reliable in his communications.

Ed Marek
The AVTA is monitoring a Chevy Volt for battery degradation. Early results are posted here: As I commented on a MNL thread: “‘2011 Chevrolet Volt VIN 0815 Plug-In Hybrid Electric Vehicle Battery Test Results’ While these results look very good at first glance, the Volt showing only ~2% degradation in kWh capacity and ~2.2% in Ah after ~7 months and ~15k miles, you can see on p.16: ‘…Fleet data results are summarized in Table 6. The vehicle accumulated 14,836 miles from May 8, 2012 to September 28, 2012, while using 1001.1 kWh of AC energy and 411.3 gallons of fuel…’ That this volt apparently ran ~70% (?) of it’s test miles on gasoline. So as a function of from-the-grid kWh throughput, the rate of degradation (from this very early test) could appear to be fairly rapid. ~2% degradation every ~4,000 electric miles (assuming ~4m/kWh average efficiency) could lead to 70% EOL at ~60,000 Electric miles, and ~220k total miles. IMO, the main reason neither of the scenarios above give an accurate picture of Volt battery degradation is that a significant factor in battery degradation is cycling from regenerative charging. This Volt had only 1001.1 kWh throughput from the grid,… Read more »
I think this is a good start on analyzing the Volt battery degradation. But the way to compare “range” by predication and driving isn’t scientific at all. The first thing to do is to drive the car from full charge to the empty in the same course and compare KWh used. That is easily found on the Volt dash board. Then compare the input charging vs that KWh used. Of course, this is also just informational since it is “pointless” to compare usable range. When battery gets less capacity, it doesn’t suck in more power, it actually sucks in less b/c it has less capacity left. So, the key to compare the Volt is the KWh consumed for each charging cycle. If that starts to drop, then you have a degradation. Of course, the critic would say how do we know that GM doesn’t just open up that window to keep the KWh consumed the same for each charging cycle. Well, that is a valid point. Here is my take on it. 1. IF you keep opening up the charging window to “hide” the capacity loss, then each time you charge, it will use up higher % of the usable… Read more »

I would also like to know the total kwhrs used from full to empty from the Volt’s energy usage screen. This is the best way to tell. Do several tests and let us know the results of each test.


Regarding some 2012’s having the 2013 16.5 kwhr battery, I have seen no evidence. It seems to me like a rumour that has taken on a life of its own.

Can someone point me to the evidence?