GM Volt Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
I have a question and possibly an issue, I recently bought a slightly used 2016 Volt (about 10,000 miles on the odometer). When I got it at the dealer it was reporting the normal 53 mile range with a full charge. I think the first time I charged it, it came back with that as well. Since then every time I charge it it's dropped the reported miles with one exception, like 48, then 45, then 44, then 42, then 39, but then today it was back up to 42. It has been roughly accurate and most of my 58ish mile daily work commute is highway so I could see that impacting the economy, but, is that something the car normally does? Like, try and guess it's charge capacity based on your previous average use? Just want to make sure there isn't a problem and it had been dipping so low I was starting to wonder...

Thanks for the assist.
 

·
Administrator
Joined
·
19,984 Posts
Repeat after me "It's an estimate based on my recent driving history."

Summary

  • New Volts have a low battery range estimate that will increase over time based on the points below.
  • Volts in cold weather will see a drop in the battery range based on the points below. This will reverse when the weather warms again.
  • Volts with battery service will see the battery range reset to the lower factory default. Just like a new Volt owner, you will see this change as you drive the car normally over the next several days.
  • Volts with multiple drivers may see a drop in the battery range based on the points below. As a passenger, you can quickly determine why your partner is getting fewer battery miles than you (or vice versa!).
New Volt owners; or those who have had some battery service done; or those driving for the first time in fall/winter months can become anxious when seeing their Volt's battery range display a mileage estimate in the 30's, rather than the 40's or even 50's they were expecting or were previously experiencing.

Some fear the lower battery range estimate indicates a battery problem of some sort. Do not panic. It is much more likely the decreased battery range (actual or estimated) is due to a change in driving style, or in environmental conditions, or the car's conditions, or all the above.

Four Main Points About Volt Battery Range

1. The battery range display is an estimate based on the past, it's not an absolute.

The Volt attempts to predict how many miles you will be able to drive on the full battery based on your past few days of driving. A brand new Volt typically has no real past driving results to base an estimate on, so it displays a range estimate of 36-38 miles. This can vary a bit based on pre-delivery driving by the dealer.

The actual miles you get from the battery can be higher or lower than the displayed estimate based on factors discussed below. In general, all things being equal, if you drive consistently every day, the Volt's battery miles estimate will come very close to the actual miles you will get. Again, this assumes little or no change in your driving style or environmental conditions.

2. Your driving style affects the battery range (actual and estimated).


The way you drive greatly affects how many miles you will get from the battery. If you change the way you drive for a few days or so, it will be reflected in the Volt's estimated battery miles as well.

  • Speed. Slower speeds will deliver more battery miles. The faster you drive the more energy it takes to push through air resistance. The battery will deliver more driving miles at a steady 30 MPH than it will at a steady 70 MPH. Generally, you'll drive further at speeds under 50 MPH than you will at speeds over 50 MPH.
  • Cruise Control. The Volt has a great cruise control. Using cruise control will often be more efficient (deliver more battery miles), than not using cruise control because many people have a hard time keeping a very consistent speed. For the Volt's cruise control, this is easy.
  • Anticipating Change: Starts and Stops. Starts and stops that keep the green ball centered in the dash will enable more miles to be driven on the battery than rapid starts and stops which will waste more energy. Anticipate stops and slow down gradually rather than "speeding to a stop". Try to maintain inertia, as a rolling start will require less energy than accelerating from a dead stop.
  • Drive vs. Low Regen. Drive creates the same amount of regen (electricity regeneration) that Low does when slowing down, but Drive takes a longer distance to do so. With Drive, you can coast, with Low you can slow the Volt down quicker without using the brakes and thus recover more battery range in a shorter distance than Drive. Some people drive in Low all the time. Some downshift into Low only when approaching slowed traffic. Some feel unsafe using Low without tapping their brakes. Whatever your choice, Low pumps more electricity back into the battery than Drive given a short stopping distance.
  • Climate Control. Not using the heater, the A/C, the defroster will be more efficient (deliver more battery miles), than using them. Eco uses more electricity than not using climate control. Comfort uses up more battery miles than Eco. Of course, if you need them, use them. Just be aware that your battery miles (and estimated range) will be reduced. At speeds less than 50 MPH, popping open the window a half inch will often clear windshield fog as well as the defroster.
  • Seat Heaters. If you need heat, the seat heaters use much less energy than using the the climate control heat. Try using the seat heaters instead of the climate control if possible.
3. Environmental conditions that affect battery range (actual and estimated).

The conditions you drive under can dramatically affect how many miles you will get from the battery. If these conditions change for a few days or so, it will be reflected in the Volt's estimated battery miles.
  • Rain/Snow. Pushing the car through water or snow on the road takes more energy (battery miles) than driving on a dry road. Higher tire rolling resistance and lower tire traction take their toll. Also, water is a more effective coolant than air, so the tires and lubricants operate at cooler (less efficient) temperatures. Plus, the wipers and defrosters are typically needed, drawing even more electricity. Wet or snowy conditions can therefore decrease miles (by up to 14% according to some Prius owners). Nothing you can do about rain or snow, just be aware you will get fewer battery miles on those days.
  • Road Surface. Concrete is the most efficient driving surface, asphalt second, chip and seal is worst. Road roughness can increase rolling resistance up to 20% due to energy dissipation in the tires and suspension (10% loss of mpg).
  • Wind. A strong headwind can reduce battery miles by increasing air resistance. Strong winds often accompany rain and snow storms.
  • Outside Temperature. Colder outside temperatures reduce driving range for a number of reasons including the fact that thicker lubricants have more resistance requiring more battery energy to overcome. Colder weather often results in increased use of the climate system, further reducing miles. Nothing you can do about outside temperature, just be aware you will get fewer battery miles on colder days than warmer days.

    The chart below from an actual Volt owner show the affect that temperature alone has on battery range (next to it is a chart showing the amount of energy used to travel 100 miles vs. outside temps). The lower the seasonal temperature, the more energy it takes to travel, resulting in fewer miles on a full charge:

    http://gm-volt.com/forum/showthread.php?151273-3-Years-of-OnStar-Data-Comparing-Effect-of-Temperature-on-EV-Range
4. Volt conditions that affect battery range (actual and estimated).

The condition of your Volt can dramatically affect how many miles you will get from the battery. If these conditions change for a few days or so, it will be reflected in the Volt's estimated battery miles.
  • Tire Pressure. Maintain the correct tire pressure. Low tire pressure can reduce you battery miles by up to 10%. Correct tire pressure is more efficient, maximizes battery miles. Low tire pressure creates more rolling resistance and therefore consumes more battery miles. Check tires weekly, or at least once per month. Some even keep their tires inflated to a slightly higher 40 psi.
  • Winter Tires and Wheels. These tires, plus their often heavier wheels, can increase rolling resistance and therefore decrease battery miles.
  • Preconditioning. The 240v EVSE charge stations have the advantage of allowing you to pre-start the Volt and warm (or cool) the cabin at max comfort temperatures for 10 minutes using (mostly) the house electricity rather than the battery. If you do this 15 minutes or so before departure, your car will have 5 minutes to replenish if needed and you won't need to draw down the battery range as much during your drive. The 120v EVSE does not supply enough power to precondition the Volt this way, and more battery power is robbed to make up the difference. A refinement is to delay charging so it completes about 15 minutes or so before you plan to leave. The battery will be a bit warmer than if it had finished charging hours earlier.
  • Clean & Waxed Car. MythBusters showed that a dirty car can decrease fuel efficiency (battery miles) by up to 10%. A clean Volt has less air resistance than a dirty Volt. It looks better too. Wash your car weekly, or at least every few weeks. Package delivery services and airlines know this and keep their equipment clean. http://dsc.discovery.com/tv-shows/my...-clean-car.htm

TIP: Keep Your Volt Plugged In

Yes, you should always keep your Volt plugged in if possible. It will not hurt the car. Instead, this allows your Volt to take care of battery management chores using grid electricity instead of using its battery. Keeping your Volt plugged in will enable you to use all your battery miles for driving.

Interesting reading: http://cumminsengines.com/assets/pdf...whitepaper.pdf

Related Battery Degradation Information

Although cold weather will not degrade the battery, what many may not realize is degree of engineering sophistication the Volt employs to coddle the LiOn battery and minimize degradation from other causes while providing maximum battery life:

  • The battery is never fully discharged. Only 10.5 kWh (usually 45-50 miles in summer, 25-35 miles in winter) of the battery's total 16 kWh can be used (16.5 kWh for MY 2013). The extra 5.5 kWh forms a buffer as well as a reserve to be used as the battery ages. LiOn batteries degrade faster if fully discharged on a regular basis, the Volt prevents this.
  • The battery temperature is maintained in a narrow range while plugged in or driving. This is done with a liquid coolant system. Extended exposure to high heat is bad for battery life. The Volt minimizes the effects of external hot or cold temperatures by using its active thermal management coolant system programmed to stay within 3.6°F (2°C) of the pack’s optimal temperature, which depending on usage conditions falls in a range between 50ºF and 85°F (10ºC to 30°C). While it is parked unplugged, the insulation around the battery helps maintain the desired temperature.
  • The battery can not be cooked with a "supercharge". The Volt does not allow rapid, half hour recharges of the depleted battery. These kind of charges can easily cook the battery if done frequently or improperly.
Related reading: http://www.myperfectautomobile.com/g...nt-system.html
Also: http://en.wikipedia.org/wiki/Chevrolet_Volt#Battery

Volt buyers pay a little more to have these advanced battery management features. To sell at a lower price, some EV's skimp on these features or skip them altogether.

GM has test Volts with well in excess of 200,000 miles still operating within spec which means the liquid-heated and cooled battery and related systems are engineered to at least go the distance in all climates. Though the battery is warranted for half that, I expect we will see many Volts still running on their original battery even after 12-16 years of use.

Related reading: http://gm-volt.com/?s=micky
 

·
Registered
Joined
·
1,034 Posts
If you want good range, don't drive it like a race car. Make a game out of it and see if you can change your driving habits to make it go back up. It is easier than you might think.

VIN # B0985
 

·
Registered
Joined
·
13,556 Posts
If you want good range, don't drive it like a race car. Make a game out of it and see if you can change your driving habits to make it go back up. It is easier than you might think.

VIN # B0985
Yes, driving like a grandpa and less like Jeff Gordon does wonders to your range. How fast are you (the OP) driving anyway? If your traffic patterns allow for this, take the same trip on subsequent days at 55, 60, 65, 70, and 75 mph and you'll get the picture.

After 2 years of driving like a grandpa trying to eek out every Ev mile out of my volt, I just gave up and just started driving. My 95mpg dropped to 70 which is still better than any Prius out there. Plus it's a lot more fun to take on pony cars and ricer boys at stop lights.
 

·
Registered
Joined
·
16 Posts
I feel your pain. Give it time and you likely will find out you have nothing to worry about. My 2017 (also used, just short of 10,000 miles at purchase) also has seen the estimated range slowly decline. It is maddening. I saw the biggest decline with a 2-week long cold spurt and thankfully the weather forecast indicates we will be warming up starting on Thursday. Also, a majority of my mileage the last 2 weeks has been done at inefficient 70+mph. I saw a post earlier, by Shane S back in 2015 that said "At a steady 55 mph, I got 4.71 miles/Kwh. At 65 mph, I got 3.35 miles/Kwh. At 75 mph I got 2.65 miles/Kwh. If I assume the usable full charge is 14.5 Kwhs (I forget the exact number given), that translates to an EV range at a steady 55 mph of 68.3 miles, at 65 mph of 48.6 miles, and at 75 mph of 38.4 miles." (Post #23) As you can see, increased speed really kills EV range.

The good news for me is at this point it seems to be very accurate in the actual EV miles I am getting. The bad news is I want more EV miles than I am getting. The secret is to slow down and (at least for me) wait for the weather to warm up. Good luck!
 

·
Registered
Joined
·
6,661 Posts
My 2017 is going in the opposite direction now that temps are moderating. My GOM (Guess-O-Meter) was displaying low fifties for the past several weeks (we've had warmer than average winter temps here in southern Illinios) but then average daily temps have increased a bit lately (low's in the 40'd and high's in the 50's) and this morning when I got in my car to head to work my GOM read 61 miles.

Since your profile and post don't provide us with your location all we can do is guess you are still experiencing some COLD temps and using the HVAC system and possible highway driving.
 

·
Registered
Joined
·
32 Posts
Steverino,
This is an EXCELLENT post. I've been lurking for years, and knew most of this, but it's a great reminder,, and a great intro to newbies. Would recommend you copy/paste this into all "what happened to my battery" posts, and make it a sticky (if not already). Thanks for the succinct but thorough overview.
 

·
Registered
Joined
·
3,500 Posts
Steverino,
This is an EXCELLENT post. I've been lurking for years, and knew most of this, but it's a great reminder,, and a great intro to newbies. Would recommend you copy/paste this into all "what happened to my battery" posts, and make it a sticky (if not already). Thanks for the succinct but thorough overview.
You can also check at the end of this thread for similar thread listings.
 

·
Administrator
Joined
·
19,984 Posts
Steverino,
This is an EXCELLENT post. I've been lurking for years, and knew most of this, but it's a great reminder,, and a great intro to newbies. Would recommend you copy/paste this into all "what happened to my battery" posts, and make it a sticky (if not already). Thanks for the succinct but thorough overview.
Thanks, it's actually a sticky thread via the Newcomers forum. Regrettably, many never look there. So I have started posting 80% of the FAQ (above) whenever this newbie question arises.
 

·
Registered
Joined
·
4,405 Posts
Drive it like you stole it. The amount of money it costs to drive a Volt is laughably low so enjoy it. It is more fun to drive than most 'green' cars.

But it's also fun to hypermile the Volt for kicks. There is certain satisfaction from getting higher than EPA ratings, and it's not hard.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #12
Yes, driving like a grandpa and less like Jeff Gordon does wonders to your range. How fast are you (the OP) driving anyway? If your traffic patterns allow for this, take the same trip on subsequent days at 55, 60, 65, 70, and 75 mph and you'll get the picture.

After 2 years of driving like a grandpa trying to eek out every Ev mile out of my volt, I just gave up and just started driving. My 95mpg dropped to 70 which is still better than any Prius out there. Plus it's a lot more fun to take on pony cars and ricer boys at stop lights.
Ok, so my work commute commute is about 52 or so miles country highway, and about 3-4 miles city (or urban, anyway). Speed limit is set at 75, but I think it's usually advisable to go a bit slower as there's a lot of crossroads and potential accidents... Unless I'm running late I mean.
 

·
Registered
Joined
·
14 Posts
Thank you for this post. I recently purchased a 17 volt and are seeing low EV range and this was concerning to me. I do live in northern MI and the temps have been barely mid 40's and my car was also a demo for 3300 miles. I have noticed I have been starting to get more miles compared to the EV range so that has made me feel a little better.
 

·
Registered
Joined
·
3 Posts
It really depends on your driving style. Since I got the Volt, I haven't driven it past 70mph. I mostly drive at 60MPH and i can get up to 70 miles for 14.1 KW. Thats from full to empty. I commute 76 miles roundtrip to my work. I'll take a screenshot when i'm fully charge. Mine shows 63-67 miles at full charge. So this is depends how you drove your car before you fully charge it.
 

·
Registered
Joined
·
3 Posts
Yeah, i agree!!! I like to hypermile it early in the morning when there's no traffic. My best hypermile so far is 5.2 KW on 38 miles. But if wanna have fun. I'll be lucky to get 2 miles per KW.
 
1 - 15 of 15 Posts
Top