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Discussion Starter #1
Nothing different, even the last charge started at 32 miles. I have the charging set for PG&E night time rate between 10PM & 7 AM with a 12 amp rate. I usually use Hold if I'm going more than 40 miles RT so that I can have a full chrge the next day [usually much shorter trips so usually charge once a week].
Night time temp in my garage is typically 60 degrees. I few times when it got lower, 50 degrees, it might just get to a charge of 50 miles.
So any thoughts?
 

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Discussion Starter #3
None of the above. Let me try again.
After a trip the remaining range is, say, 38 miles. I plug it in to charge over night and the next day I even get an Onstar email with "charging complete". However when I get in the car [for the past 3 times] it shows "full charge" but only 46 miles range.
 

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None of the above. Let me try again.
After a trip the remaining range is, say, 38 miles. I plug it in to charge over night and the next day I even get an Onstar email with "charging complete". However when I get in the car [for the past 3 times] it shows "full charge" but only 46 miles range.
The range it's giving is based on the energy use on your recent driving.
Next time, check the Energy Info to see how many miles you've driven and how many kWh you used and then figure out how that would translate to effective range.
 

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suggest taking a normal drive and see how many miles you get out of the battery. Then report back. The GOM values displayed can go wonky from time to time.
 

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Discussion Starter #6
The range it's giving is based on the energy use on your recent driving.
Next time, check the Energy Info to see how many miles you've driven and how many kWh you used and then figure out how that would translate to effective range.
One of the recent times I forgot to "Hold" and got home with 5 miles remaining, The overnight charge got it to 40 miles. Went just 2 miles the next day and charged over night with "full" charge at 46 miles.
 

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Discussion Starter #7
I'm not too sure what you mean by that. Let's say I start with a full charge of 46 miles. My "normal" drive is ~ 40 miles RT. Let's say I get home with ~ 5 miles. Or 10 miles. Or 0 miles? What will that tell me?
 

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I'm not too sure what you mean by that. Let's say I start with a full charge of 46 miles. My "normal" drive is ~ 40 miles RT. Let's say I get home with ~ 5 miles. Or 10 miles. Or 0 miles? What will that tell me?
Not much.
The Energy Info screen is a better thing to look at since it gives EV miles and kWh used since last full charge.
Equivalent range = 14kWh x <EV miles> / <kWh used> (assuming 14kWh is the usable capacity of the Gen 2 Volt's battery).
The numbers have to be calculated and they can get a bit messed up in some cases, but generally it'll give you a reasonable estimate of energy use and where you'd expect range to be, rather than the car's estimate that's based on more driving history.
 

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Nothing different, even the last charge started at 32 miles. I have the charging set for PG&E night time rate between 10PM & 7 AM with a 12 amp rate. I usually use Hold if I'm going more than 40 miles RT so that I can have a full chrge the next day [usually much shorter trips so usually charge once a week].
Night time temp in my garage is typically 60 degrees. I few times when it got lower, 50 degrees, it might just get to a charge of 50 miles.
So any thoughts?
It's normal. We get this question every year as fall approaches.

What you need to understand is that GM took a different approach than some other people, and a mile of range on the dash doesn't represent a fixed amount of energy in the battery. Instead, the car uses your actual consumption from the last couple of drives and the outside temperature to create an estimate of how far you can drive today.

If you drive it gently with no HVAC, you'll see the range in the morning trend upwards. If you drive aggressively with a lot of HVAC, you'll see the numbers plunge. Two Volts can be sitting side by side with identical charge in the battery and show very different ranges based on how they've been driven before.

In this case, the cooler weather means more energy spent overcoming tire friction and air drag, more energy spent on HVAC, and less energy available from the battery cells - so the estimate in the morning goes down.
 

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I'm not too sure what you mean by that. Let's say I start with a full charge of 46 miles. My "normal" drive is ~ 40 miles RT. Let's say I get home with ~ 5 miles. Or 10 miles. Or 0 miles? What will that tell me?
I think you're not understanding what the "Range" number is. That number is the *estimated* range the car is predicting you can drive on the amount of battery charge you have. That estimate is based on a lot of factors, but mostly it's based on your recent driving history. For example, if spend a week where every day you spend of your time going 80 mph on the freeway, the amount of range it will say you have on a full charge will drop considerably because going 80 uses a lot more power than going 40 around town. And since that's what you've been doing, it will expect that to be what you keep doing and therefore drop the estimate.

So let's say you've done that: drove 80 mph for a week. You get in your car, the charge shows full, and the range estimate says 40 miles. Now go out and drive around town ~40 mph - you will find that you will be able to drive a LOT more than 40 miles before the charge is depleted.

Around here they call that range number on the dash the "Guess-O-Meter" for a reason. It's the car's best guess at how far you can go based on how you have been using it.
 

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I'm not too sure what you mean by that. Let's say I start with a full charge of 46 miles. My "normal" drive is ~ 40 miles RT. Let's say I get home with ~ 5 miles. Or 10 miles. Or 0 miles? What will that tell me?

Well, in your case if you got home with 5 miles left, then it means you drove your car consistent with the last few times you've driven it because it's guess and your actual milage were very close. If you get home at there were 0 left, then it means you either drive faster than usual, up more hills, or it was colder and the car had to spend some battery heating, etc.

If you're expecting that range number to be 1-to-1 for the miles you've driven, then you're going to be disappointed.

Think of that thing like the "time remaining" display of your laptop battery. Your laptop has not idea if you're about to watch a movie, sit there idle reading a web page, or start a simulation of the early formation of the universe. It only knows how you have been using it recently and, based on that, predicts how much time you have left.
 

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I'm not too sure what you mean by that. Let's say I start with a full charge of 46 miles. My "normal" drive is ~ 40 miles RT. Let's say I get home with ~ 5 miles. Or 10 miles. Or 0 miles? What will that tell me?
The full-charge range estimate merely multiplies the amount of usable power available in a full charge (~14 kWh for a Gen 2) by a computer estimate of your average electric mileage, based on your historical and recent driving habits. If your full charge estimate is 46 miles, then the computer estimate is suggesting your driving habits tend to give you a mileage of 3.3 miles/kWh (3.3 x 14 = 46.2). If you drive 40 miles (all on battery power, no Hold mode) and arrive home with 5 estimated miles remaining, you’re driving mostly as you normally do (total range ~45-46 miles). If you arrive home after those 40 miles with 10 estimated miles remaining, you’re getting slightly better than usual mileage (used slightly less power to go 40 miles so had more estimated miles remaining). Perhaps the average speed was slower or the terrain flatter or the temperature was just right, and the next day’s full charge estimate may take this performance into account and increase the full charge estimate to 47 miles. If you arrive home with the battery at 0 miles after those 40 miles, then the average mileage was reduced from your normal use. Perhaps it was raining or hilly or more freeway speeds or you used more heat or a/c. This day’s mileage might have been 40/14 = 2.86 miles/kWh. The following day’s full charge estimate may be only 45 or so. (Note: sometimes it takes several days of above or below performance to affect the computations that create the full charge range estimate.)

Neither a gallon or gas nor a kWh of electricity contains a "guaranteed number of units of driving distance." Window sticker numbers suggest how far you could drive under the conditions used to set the rated distances. Your mileage may vary.

"Saving" the battery by driving in Hold (Range Extending mode) can skew this estimate. If you switch to Hold for much of your commute and never fully deplete the battery, the computer will take a mileage estimate based on the portion of your commute when you are actually driving on battery power, and multiply that by the power available in a full charge to give you a full-charge range estimate.

The amount of estimated ev miles remaining when you plug in and recharge has little to do with the subsequent full-charge range estimate. One says, "if you had continued to drive on battery power under the same driving conditions you were just experiencing, this is how far you could have gone." The full-charge estimate says, "based on your historical ev driving data, this is how far you can expect to drive under the driving conditions you normally have."

It is unclear why you use Hold at all, and not just drive until the battery is fully depleted. 10 pm - 7 am is not sufficient time for a 120-volt full recharge, so you are choosing to use gas instead of fully depleting your battery and then fully recharging by starting the recharge before the night rates kick in or continuing after they end. Yes, you can get only so much recharging done in that 9-hour recharging window. If you then unplug before the charge is complete, the estimated range number will be based on the less-than-full-charge amount of available usable power. That number is estimating how far you can go on that partial charge, and should not be compared to any full-charge range estimate.
 

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Discussion Starter #13
The full-charge range estimate merely multiplies the amount of usable power available in a full charge (~14 kWh for a Gen 2) by a computer estimate of your average electric mileage, based on your historical and recent driving habits. If your full charge estimate is 46 miles, then the computer estimate is suggesting your driving habits tend to give you a mileage of 3.3 miles/kWh (3.3 x 14 = 46.2). If you drive 40 miles (all on battery power, no Hold mode) and arrive home with 5 estimated miles remaining, you’re driving mostly as you normally do (total range ~45-46 miles). If you arrive home after those 40 miles with 10 estimated miles remaining, you’re getting slightly better than usual mileage (used slightly less power to go 40 miles so had more estimated miles remaining). Perhaps the average speed was slower or the terrain flatter or the temperature was just right, and the next day’s full charge estimate may take this performance into account and increase the full charge estimate to 47 miles. If you arrive home with the battery at 0 miles after those 40 miles, then the average mileage was reduced from your normal use. Perhaps it was raining or hilly or more freeway speeds or you used more heat or a/c. This day’s mileage might have been 40/14 = 2.86 miles/kWh. The following day’s full charge estimate may be only 45 or so. (Note: sometimes it takes several days of above or below performance to affect the computations that create the full charge range estimate.)

Neither a gallon or gas nor a kWh of electricity contains a "guaranteed number of units of driving distance." Window sticker numbers suggest how far you could drive under the conditions used to set the rated distances. Your mileage may vary.

"Saving" the battery by driving in Hold (Range Extending mode) can skew this estimate. If you switch to Hold for much of your commute and never fully deplete the battery, the computer will take a mileage estimate based on the portion of your commute when you are actually driving on battery power, and multiply that by the power available in a full charge to give you a full-charge range estimate.

The amount of estimated ev miles remaining when you plug in and recharge has little to do with the subsequent full-charge range estimate. One says, "if you had continued to drive on battery power under the same driving conditions you were just experiencing, this is how far you could have gone." The full-charge estimate says, "based on your historical ev driving data, this is how far you can expect to drive under the driving conditions you normally have."

It is unclear why you use Hold at all, and not just drive until the battery is fully depleted. 10 pm - 7 am is not sufficient time for a 120-volt full recharge, so you are choosing to use gas instead of fully depleting your battery and then fully recharging by starting the recharge before the night rates kick in or continuing after they end. Yes, you can get only so much recharging done in that 9-hour recharging window. If you then unplug before the charge is complete, the estimated range number will be based on the less-than-full-charge amount of available usable power. That number is estimating how far you can go on that partial charge, and should not be compared to any full-charge range estimate.
I use the hold so that I can get a full charge for the next day of driving.
Interesting & I appreciate the how the computer does this. But why? Why can't the computer, if there is enough time to charge to 53 miles, choose not too? Over what time frame [days/weeks/months] does the computer use to make its decision?
My daily/weekly/monthly trips can vary from a daily 2 mile trip to where I walk, to a once a week 45 mile RT to grocery shopping, a monthly 75 mile RT to Costco, to a 275 mile RT to visit a friend every other month. So if I'm going to make the longer trip I'd sure like to start with a full 53 mile charge, using a combination of city, EV & freeway ICE.
I guess I have to live with it. Is there a benefit to the batteries, car operation? Give the programmers something to do [I'm not trying to be nasty just enquiring minds need to know]?
 

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Why can't the computer, if there is enough time to charge to 53 miles, choose not too? Over what time frame [days/weeks/months] does the computer use to make its decision?
Forget about a full charge = 53 miles. That works only on the EPA test track. Just look at the Battery Charge Bars. There are 10 bars on the screen that indicate the State of Charge. 10 bars = 100% Full Charge.
 

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The OP seems to be having a hard time grasping that the number displayed is an ESTIMATE for a full battery based on past driving data.

It's not a meter. It's simply showing how many miles it thinks you will be able to drive on a full battery based on how many you have been getting in the past. Drive aggressively, or at 90 MPH, or on lots of cold days, or with under inflated tires, etc. (or all the above), and that ESTIMATE may display 35 miles for a fully charged battery. Do the opposite and the ESTIMATE may display 65 miles.
 

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Discussion Starter #17
The OP seems to be having a hard time grasping that the number displayed is an ESTIMATE for a full battery based on past driving data.

It's not a meter. It's simply showing how many miles it thinks you will be able to drive on a full battery based on how many you have been getting in the past. Drive aggressively, or at 90 MPH, or on lots of cold days, or with under inflated tires, etc. (or all the above), and that ESTIMATE may display 35 miles for a fully charged battery. Do the opposite and the ESTIMATE may display 65 miles.
I do the opposite.... never mind
 

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I usually use Hold if I'm going more than 40 miles RT so that I can have a full chrge the next day [usually much shorter trips so usually charge once a week]... So any thoughts?
Here's a fascinating read that Steverino recently linked:
http://gm-volt.com/2013/02/26/a-tale-of-two-volts-the-summary/

Consider completely discharging your battery a couple times, rather than retaining charge via unnecessary hold mode. We recently bought a demo 2017 LT with a couple thousand miles already on the odometer. Almost all of those demo miles were gas miles rather than electric. Our initial estimated range on the guess-o-meter was typically in the upper 40's or lower 50's. After running the battery COMPLETELY down a few times, our guess-o-meter now typically predicts around a 60 or 62 mile range. Of course that predicted range will once again go down, as the temperatures decrease.
 

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full is an fixed amount of energy, not a fixed amount of range

Thinking about a full charge as "53 miles of range" is the flaw in your thinking. It makes more sense, and is more literally correct, to consider full charge as meaning there are 14kWh available in the battery for use by the car.

Typically you'll get bit less than 4 miles of range per kWh.
In great weather and perfect conditions(low speed, not a lot of start/stop, not a lot of hills, little use of climate control), people achieve better than 5 miles of range per kWh.

In winter, when the car is using a lot of energy to warm the cabin and battery, and the dense air and viscous lubricants/ cold tires are factors, getting less than 3 miles of range per kWh can occur.

You mentioned the 'computer stopping charge at 46 miles" If you got a charge complete message, the computer didn't stop at 46 miles of range. It stopped when the battery reached its 'full' state of charge, giving the car about the same amount of energy as any other full charge, regardless of the estimated range.

I hope this helps, keep asking questions here if this doesn't clear up your thinking.

-Lumos
2014 gen1
 

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"full" is 14.1 kWh -- 53 miles is the estimated "normal" range by smooth easy driving.

It can be much better or much worse depending on temp/terrain/heat/ac and how much hard accelerating you do. Drive it like nascar and you will have crappy range. Drive it in the winter, you will have reduced range.

Make a conscious effort to drive like a granny for 3 or 4 days you will have some awesome range. Even though I commute 70 miles (mostly highway) I can still get the thing to say 56 to 58 miles of range if I granny drive it and use hold mode on the highway if I'm doing 60-75mph+

These cars deliver optimal efficiency in low-medium city driving environments ~30-45mph, blasting down the highway doing 75+ sucks juice like crazy and destroys your "estimated" range.
 
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