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I just got my USED 2016 Premier yesterday. It only has 7700 Miles on it. I plugged it in overnight (on the provided Level 1 charger), it says it's fully charged and the total EV range is 45 miles. What gives? Shouldn't I get at least 50?

I think the car might have sat for awhile not being charged. Should I expect the number to go up after a couple more charges? Would taking it to a Level 2 charging station and use that once or twice help?

I'm just confused, I thought the EV range was supposed to be 53 and other are reporting over 60 at times.

Thanks!
 

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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...a-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

http://news.fleetcarma.com/2014/01/1...el-efficiency/
 

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Ditto that ^. It is an estimate. Check actual mileage after you drive.
 

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Please read Steverino's post several times until you have grasped all the information clearly. However, the battery capacity info is for the Gen1 Volt, so the Gen2 will have higher kWh storage capacity and therefore higher range capability.

The range projection is a combination of the Volt battery state of charge and the historical driving techniques of the driver(s). Drive gently and get higher range projections, drive it like you stole it and get lower range projections. Add in terrain, temperature and environmental factors for good measure.

VIN # B0985
 

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Drive vs. Low Regen. Whatever your choice, Low pumps more electricity back into the battery than Drive given a short stopping distance.
To be clear, coasting in D is more efficient than using regen to return electricity to the battery. This is due to conversion losses encountered both going into and coming out of the battery. Hence the importance of anticipating traffic in order to have room to coast rather than having to use regen to slow.

KNS
 

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Additional evidence the range estimates are individual-vehicle-driving-history specific. The full charge, or start of day range estimates are also "fuel history specific."

If the only time you use the gas engine is for short distances when it doesn’t have time to warm up, the gas mileage will be lousy, and if that’s how you’ve been using the gas engine lately, multiplying that by a full tank of gas will produce a very low gas range estimate. Take a long drive in that Volt one day, far enough to use one gallon or more of gas with the engine properly warmed up, and the following day’s gas range estimate will reflect that recent improved gas mileage.

If you drive but 20 electric miles a day, but drive very efficiently and do it frequently, the computer multiplies the good ev mileage by the full charge available power (for Gen 2 Volts, that’s ~14 kWh) to produce high full charge ev range estimates, perhaps into the 60s and 70s. Not all drivers are able to maintain that high ev mileage rate when driving until the battery is fully depleted, so when they actually drive only 55-65 or fewer miles on a full charge, the next day’s full charge range has decreased.
 

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Discussion Starter #7
@Steverino Awesome post, thank you!! The Volt WAS in NJ and is now in AZ, so any cold weather issues should go away, especially in about 4 weeks.

I really don't drive much, I work from home and usually only drive about 10-15 miles around to the store or the kids school etc. So it will be awhile for me to run it all the way down. I went out today and it said there were 43 EV miles, I drove at least 10 miles and it went down to 36 EV miles, so I was getting more than it said. Probably got a little back from braking and coasting etc.

Thanks again, I will re-read everyone's suggestions.

- Mike
 

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To be clear, coasting in D is more efficient than using regen to return electricity to the battery. This is due to conversion losses encountered both going into and coming out of the battery. Hence the importance of anticipating traffic in order to have room to coast rather than having to use regen to slow.

KNS
So given the short stopping distance referenced in the quot you pulled, you'd rather coast in Drive into a hard braking rather than using Low? To each their own.
 

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So given the short stopping distance referenced in the quot you pulled, you'd rather coast in Drive into a hard braking rather than using Low? To each their own.
No you would rather apply constant deceleration, at the threshold required to come to a dead stop exactly where you need to. Whether you do this using the pedal, the paddle or coasting is your choice.
 

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You've exposed yourself as a newb.... be patient it will go up, unless you drive like Jeff Gordon. Drive like a grandpa, and you will be rewarded. Give it a week or so.
 

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Take a chill, let the car "learn" your driving patterns and then you have to learn to master the THREE T's - Terrain, Temperature and Technique and then you'll get a more accurate picture of how far you can drive on a kW. A good goal to start with is 3.5 miles per kW.

Many of us have no trouble reaching 4 miles per kW. What that means looks like this 14.4 kW x 4 = 57 miles. Good luck.
 

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Take a chill, let the car "learn" your driving patterns and then you have to learn to master the THREE T's - Terrain, Temperature and Technique and then you'll get a more accurate picture of how far you can drive on a kW. A good goal to start with is 3.5 miles per kW.

Many of us have no trouble reaching 4 miles per kW. What that means looks like this 14.4 kW x 4 = 57 miles. Good luck.
Last fall after I first got my car, I reached 62 miles several times (actual EV driving...not estimated); this summer will probably be even higher now that I have more practice driving efficiently.
 
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