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Discussion Starter #1
I've had my Bolt for 10 days and I noticed something odd this morning.

After a 135 mile trip yesterday, I had taken it down to 15 miles of range and needed a 240V charge. As I don't have my EVSE installed yet, I went to a local charger and plugged in for the night at 1830hrs. The car texted me that she was full at 0350hrs. When I started her up this morning, I found that my range was 205 miles. In the past this number was 230 ish after a full charge. In addition, the circular arrows around the 'regen' graphic are gray not green. The hilltop mode is turned off as I live in a flat area of central Michigan. Its roughly 45F today. I've used this very same charger a couple of times before without issue.

Does this warrant a trip to the Chevy dealer for a checkout? Or am I being a "Nervous Nellie" and ranges vary after full charges.

Dayle
 

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Range varies. Based on actual driving - the car is calculating your estimated ranged based on how you have driven in the past..nothing wrong with the battery, but range will changed based on driving habits.
 

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What David said and you will see the estimated range improve again in the summer when the weather warms up. When the car is new you will see changes in this estimate fluctuate quite easily. As the car gets more data points it won't change as drastically as it learns your driving profile.

It's something that is often hard to explain to people new to ev's is that your range is most likely to be different than my range based on the way you drive and where you drive, your geography and the like. It won't matter as much with the Bolt and it's larger battery but it was really noticeable in the Volt with its small battery. Chevys range estimation programming is really good at learning your driving profile and giving you a really accurate range estimate. After five years in my Volt it is uncannily accurate at estimating my range.
 

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Discussion Starter #4
The past two 'tanks' were 90% highway miles....not much regen and a 3.3 mi/kWh value. Today I was around town and I've noticed the range + driven is 223.....much greater than the 205 initial reading. The miles/kWh is way up to 4.0.

Thanks for talking me off the ledge folks,
Dayle
 

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On Chevy's site I think they have some thing on best practices so if you want to refine your way of driving to resonate with how the Bolt was intended to be driven, then that might be a start.
 

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The past two 'tanks' were 90% highway miles....not much regen and a 3.3 mi/kWh value. Today I was around town and I've noticed the range + driven is 223.....much greater than the 205 initial reading. The miles/kWh is way up to 4.0.

Thanks for talking me off the ledge folks,
Dayle
There's a reason they call it a GOM GuessOMeter it's basically dependent on how things have been driven.

The Greyed out Regen Icon is because you were full. If you were to try to slow down with the paddle or in L you'd notice you didn't have much if any regen.

I keep the Hilltop Reserve on to avoid the change in driving. It will sometimes catch you off guard when you're expecting to slow down and it doesn't.
 

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In addition, the circular arrows around the 'regen' graphic are gray not green. The hilltop mode is turned off as I live in a flat area of central Michigan.
Regen is reduced or disabled when the battery is full since it depends on being able to use the motor as a generator to put energy back into the battery. When the battery is full, you can't put any more energy into it and therefore you get little or no regen. The regen graphic turns grey to indicate this. After you drive around and use up some of the energy in the battery, there will once again be some "headroom" to use for regen and the graphic will go back to normal.

If you want to have regen available after charging then you should select "hilltop mode". It will leave a bit of extra room to store more energy in the battery so that regen will work normally.
 

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The past two 'tanks' were 90% highway miles....not much regen and a 3.3 mi/kWh value.
A somewhat different view on the phenomena 'regen':

Regen does not give you additional energy (or range). Instead, it prevents you from loosing energy that would have been lost when you were forced to use friction braking. Sounds the same. But is it?

Regen appears to be a good thing. Indeed, it is a good thing to have the capability to regen, but it is a bad thing to actually use it. When you have a lot speed changes, you may see a lot of regen, but still your range will be relatively poor. Simply because regen is not 100% efficient. Regen capability just makes the impact speed changes have on an EV smaller compared to the impact speed changes have on a normal ICE car. But preventing speed change where possible does much more for improving range than using regen instead of friction brakes.

On the highway there should not be a lot of speed changes. So, there is not much (to gain by) regen braking. For range, this is a good thing. On the highway, it is not the absence of regen braking that causes the low miles/kWh, it is the sheer speed and the associated drag.
 

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The past two 'tanks' were 90% highway miles....not much regen and a 3.3 mi/kWh value. Today I was around town and I've noticed the range + driven is 223.....much greater than the 205 initial reading. The miles/kWh is way up to 4.0.

Thanks for talking me off the ledge folks,
Dayle
Unless you need the full range I suggest you turn hiltop on anyway

the gray circle around the regen iindicates it's not ccharging the battery - as it is full - you will also notice a difference in the one pedal driving brake effect - until regen kicks in - after 3-5 kw have been used
 

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The past two 'tanks' were 90% highway miles....not much regen and a 3.3 mi/kWh value. Today I was around town and I've noticed the range + driven is 223.....much greater than the 205 initial reading. The miles/kWh is way up to 4.0.

Thanks for talking me off the ledge folks,
Dayle
Unless you need the full range I suggest you turn hiltop on anyway

the gray circle around the regen iindicates it's not ccharging the battery - as it is full - you will also notice a difference in the one pedal driving brake effect - until regen kicks in - after 3-5 kw have been used
It will regen when grey. There is a line that shows max regen. When the regen turns green it can regen at max rate not partial.
 

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Tesla recommend not fully charing LiOn batteries to full each and every day - and has a default "daily" charge setting of 90% - this will supposedly extend the life of the battery. I work for a tech firm and have co-workers that are legit battery engineers and they also claim that "topping off" a LiOn battery to full and keeping it at "full" isn't good for the battery.

Based on this experience I'm leaving the "hill top reserve" setting on all the time unless I'm planning some long distance driving.

YMMV.
 

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Tesla recommend not fully charing LiOn batteries to full each and every day - and has a default "daily" charge setting of 90% - this will supposedly extend the life of the battery. I work for a tech firm and have co-workers that are legit battery engineers and they also claim that "topping off" a LiOn battery to full and keeping it at "full" isn't good for the battery.

Based on this experience I'm leaving the "hill top reserve" setting on all the time unless I'm planning some long distance driving.

YMMV.
good to know, I barely use the full range in my daily commute. But, what does Chevy recommend ? :)
 

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A somewhat different view on the phenomena 'regen':

Regen does not give you additional energy (or range). Instead, it prevents you from loosing energy that would have been lost when you were forced to use friction braking. Sounds the same. But is it?
unless maybe when you are coming down from Tahoe ? :) Does same some braking efforts tho
 

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Based on this experience I'm leaving the "hill top reserve" setting on all the time unless I'm planning some long distance driving.
I am doing this too.

It is what I did with my Leaf too and it caused me to miss, by one month, the five year deadline for a free pack replacement. It will be a bummer if something similar happens with the Bolt.

Ed
 

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I am doing this too.

It is what I did with my Leaf too and it caused me to miss, by one month, the five year deadline for a free pack replacement. It will be a bummer if something similar happens with the Bolt.

Ed
With Chevy's verbiage of "Depending on use, the battery may degrade as little as 10 percent to as much as 40 percent of capacity over the warranty period." it would prolly be hard for you NOT to miss the free pack replacement :)
 

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unless maybe when you are coming down from Tahoe ? :)
I guess Tahoe is a hill or mountain? ;-)

Being 'a little' pedantic: You are converting potential energy (from the height) into electrical energy in the battery, rather than into warmth. Much better than friction braking your way down. But still, it helps you save energy rather than gain energy. Losses are involved in saving the electrical energy into the battery and extracting it from the battery later when you need it again. Had you not have used regen braking on your descent, you would have ended up at the bottom of the hill at a much higher speed and been able to coast much further. Not feasible, maybe ....

Correcting myself: it is not about maintaining a constant speed, but about maintaining a constant energy level (potential + kinetic)
 

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Missing the time allowance to change the battery can be even worse come time to sell the vehicle if that's a route someone takes since potential buyers that know what they're getting into will factor that into the sale. So resale value is another thing to worry about here.
 
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