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New to the forum, and a new to Chevy volt. I just bought a 2017 volt with 18000 miles. I live in the heart of the mountains, in Arizona. When I leave town there is a 4 mile long downhill route I take, I set the cruise at 25mph and when I get to the bottom of the route I regenerate between 10 and 12 miles of range. Some spots on that route regenerate as low as 0.5Kw and as high as 25Kw, with the average being roughly 13Kw. I first thought it may be an issue when I took that route with a full charge, I had 53 miles of range at the start, and 64 miles of range at the bottom. I plugged the car in yesterday and charged it to 100% and when I got in the car it says I now have a 78 mile range, and after two bars of charge are consumed it says 53 mile range.

Like any other owner I want my battery to last as long as possible, I charge on level 1 110volt. I tried to call Chevy customer service to ask about this, but ended talking to a woman whose only knowledge of the volt was to literally read the owners manual to me.

The terrain I live in is rugged to say the least, some hills will draw 40Kw for 1/2 mile with the cruise set at 65, but on the flip side are long down hills.

What are your thoughts on this guys? I appreciate it, and just want to keep my volt healthy.
 

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You will be fine. The Volt will disable regen if the battery SOC gets too high. It is designed to protect itself in almost all conditions.
 

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In the fall and winter you can use the Volt's electric heat to burn off ~1 kWh as you start your drive, then regen will replenish the battery on your downhill route.
 

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If your battery is at 100% when you start, your regen will be disabled and you'll have to use friction brakes on your long initial downhill. It would be better on your brakes if you could stop short of full when you are recharging overnight, then let the motor slow you down - and charge the battery to full - on the way down.
 

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The EV miles you are seeing on the guess-o-meter is simply a guess based on your driving habit and terrain conditions, etc. It will vary from time to time. The higher-than-53-number usually indicates you are driving efficiently, and the car is predicting you will get that many EV miles given the same driving efficiency and similar environmental conditions.
 

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The car definitely takes care of its self. If regen is not being disabled, you are not charging up to the top of the buffer, so you can forget about it. If you want a little more margin, you could plan to depart with a partial charge. You can use the delayed charge settings to make that more automated (so you don't have to remember to unplug it to avoid a full charge).

I think this car is excellent for mountain driving because the regen makes it so easy and efficient to control your speed downhill. You also keep full power despite higher elevations.
 

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Yes, the car will look after itself. The Guess o meter is just that. I start off at 68 Km and on the 8 Km. drive into town in L which is hilly and not noticeably but must be up hill as I am going from the ocean to inland of the island, it will read as high as 70 Km (so far). It isn't "free" electricity however as it self corrects as I stop and start going to the various places to do my errands. It is only a guess.
 

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New to the forum, and a new to Chevy volt. I just bought a 2017 volt with 18000 miles. I live in the heart of the mountains, in Arizona. When I leave town there is a 4 mile long downhill route I take, I set the cruise at 25mph and when I get to the bottom of the route I regenerate between 10 and 12 miles of range.
...
What are your thoughts on this guys? I appreciate it, and just want to keep my volt healthy.
Read this gem:

" 02-01-2012 #18 Chevrolet Customer Svc
Senior Member
Join Date Aug 2010
Location Detroit, MI

@ pauldon,
You have come across a feature of the vehicle which protects the battery from overcharging. Under certain circumstances, the electric motors will resist one another to provide braking in addition to the friction brakes on the vehicle. In order to meet emission requirements, the Volt does not spin the engine, but uses clutch 2 in the drive unit to link both motors. When the vehicle is at low speeds, clutch 2 requires that the resultant planetary gearset speeds increase to compensate. You will hear the electric motors at higher speeds, which is certainly a change from their normally silent operation.

The Volt was validated using the steepest, longest descent in the nation, Pike's Peak. With a full battery, the volt can descend Pike's Peak without issue with a combination of friction brakes and the electric motors. This is part of the Voltec propulsion system which has many more delighting features waiting for you to discover.

Volt Advisor Trevor -- Chevrolet Volt Advisor Team -- (877) 486-5846 -- [email protected] "
 

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Discussion Starter #9
I really appreciate the responses guys. The regen has never disabled on me, I have only the car about two weeks. I try to keep it plugged in at least during the day, it already hit 80 degrees here at 8 this morning, so I keep it plugged it during the day when I am not driving. According to my wife I am a “battery nazi” as battery health is usually on my mind.

So far I love this car, and I have been hanging around here on the forum for about a month reading and poking around. It seems to me the volt crowd reminds me of the Subaru crowd in that it seems to be a very loyal following.

Thanks again, you’ve put my mind at ease.
 

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According to my wife I am a “battery nazi” as battery health is usually on my mind.
The thing to remember is that the Volt was designed to regulate the battery's condition in order to preserve its life. With your cell phone or laptop battery, you might try to keep the temperature constant; not charge fully (or charge fully, depending on the current recommendation, which seems to change with the wind); etc etc, and maybe these actions will help prolong the life of your battery. The Volt, in contrast, regulates the temperature, and controls which cells are charged/discharged. And it keeps something like 20% of its capacity in reserve, so that as cells lose their ability to hold charge, they are retired and replaced with a reserve cell.

All this means that you just don't have to worry about battery health. The car does it for you - and, judging by the longevity of gen 1 Volts, does it very well.
 

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Read this gem:
Doesn't sound healthy. If it does use two motors to slow down heat is generated in drive unit. It is not designed to dissipate heat, that's the job for friction brakes. This is like using L to slow downhill with a regular AT. Not good.

If you are a battery nazi I would partially charge the battery and let gravity charge the rest. You can figure out how much your commute charges with couple iterations. Using off-peak charging and adjusting the hours you can achieve desired charging level.
 

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Doesn't sound healthy. If it does use two motors to slow down heat is generated in drive unit. It is not designed to dissipate heat, that's the job for friction brakes. This is like using L to slow downhill with a regular AT. Not good.
This is why the Volt has three cooling systems - ICE engine coolant, High Voltage Battery coolant, and High Voltage Electronics coolant. Also, if it was bad for the transmission to use L in an ICE engine to maintain speed downhill, why does Toyota offer a "B" (engine braking) shift position and why do semis downshift for long grades as well?

To OP, as others have already pointed out the Volt protects it's battery from both over/under-charging and temperature extremes. In the case of heading down a hill in L it will run the electric motors against each other to provide engine braking and use the high voltage equipment cooling system to dissipate the resulting heat.
 

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Doesn't sound healthy. If it does use two motors to slow down heat is generated in drive unit. It is not designed to dissipate heat, that's the job for friction brakes. This is like using L to slow downhill with a regular AT. Not good.

If you are a battery nazi I would partially charge the battery and let gravity charge the rest. You can figure out how much your commute charges with couple iterations. Using off-peak charging and adjusting the hours you can achieve desired charging level.
Well, the transaxle has its own radiator, so it was designed to dissipate some heat. But if it makes you feel any better, the very existence of that mode has been argued here by experts (WOT saying he's 100% sure there is no such mode, saghost saying it exists and he has field data showing it). I still don't know what to think...
 

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Hitting "the wall" and loosing regen is like slapping the shifter out of L and into N. Also the brakes suddenly get way more grabby and not blended and smooth at all.

I've done it a few times coming down from TN to NC and into SC on I26. I like it, it means I went from 40 something to 60 something EV range, and im topped up.
 

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When the battery is fully charged I drive up the driveway (100 feet) then go down a steep hill (one short block) and I always have regen in L. Not sure if the 100 feet up uses enough juice for regen in the block down or not.
 

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New to the forum, and a new to Chevy volt. I just bought a 2017 volt with 18000 miles. I live in the heart of the mountains, in Arizona. When I leave town there is a 4 mile long downhill route I take, I set the cruise at 25mph and when I get to the bottom of the route I regenerate between 10 and 12 miles of range...
I doubt if driving 4 miles downhill put 10-12 miles’ worth of regen into your battery, especially if you started with a nearly fully charged battery.

The increase in estimated ev range at the bottom of a hill is primarily, if not entirely, because of the increase in fuel mileage that comes from driving downhill. You use little, if any, fuel when driving downhill, so the average fuel mileage increases as you continue to drive downhill, and so does the estimated ev range... once you reach the bottom and return to driving on level terrain, the range quickly drops again as the average fuel mileage increases again.

My grocery store is 3.8 miles from my home at a lower elevation, and often my estimated ev range increases by 1 mile by the time I get there... the energy usage screen, however, shows me I’ve used 0.6 kWh (6.3 miles/kWh!). The range increase is derived from the "downhill driving" mileage improvement.

Note that the "kWh Used" number on the energy usage display in the center console is a net calculation: grid power used less regen put back into the battery. Observe this display as you drive downhill when you start out from home. If the number decreases as you drive downhill, you’re putting regen into the battery. If not, you’re not.
 

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Hitting "the wall" and loosing regen is like slapping the shifter out of L and into N. Also the brakes suddenly get way more grabby and not blended and smooth at all.

I've done it a few times coming down from TN to NC and into SC on I26. I like it, it means I went from 40 something to 60 something EV range, and im topped up.
That's what I would expect. It would be too stupid to dissipate the heat generated by a 3500 lbs chunk of metal going downhill on copper wires that melts at a mere 1000C. The drive unit cooling system pressure cap is rated at 5psi, definitely not designed to dissipate heat from anything but lukewarm coolant.

Semi's engine braking is another story. They have to use everything that can help slow down the vehicle (and designed accordingly). I won't use engine braking on a Toyota everyday. Premature braking of tranny components is guaranteed. At least ATF will go bad earlier.
 

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As others have said, GM engineered the Volt to take care of it self. Now if your still concerned, one option in is to unplug the car about 20 minutes before your departure and "pre-condition" the cabin. That will lower your SOC a bit giving you enough room for normal re-gen. Plus if your using the HVAC to heat/cool the cabin that will be consuming some kW's as well.

In your situation you'd get FREE cabin HVAC on your way down hill so by the time you reach the bottom your cabin is comfortable and the HVAC will use less power from then on, increasing your efficiency even more at that point. That's a WIN-WIN.
 

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Discussion Starter #19
Note that the "kWh Used" number on the energy usage display in the center console is a net calculation: grid power used less regen put back into the battery. Observe this display as you drive downhill when you start out from home. If the number decreases as you drive downhill, you’re putting regen into the battery. If not, you’re not.
I appreciate the info, and will check out the KWh Used on the display next time I take that route.
 

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If you hit a good BUMP you will know what lack of re-gen is like.

And other that living at a hill top and leaving for work with a full charge - I have never had my battery go back to full while driving.

On my 2012 volts 16 KWH battery I only get to play with the 10.5 KWh some where in the middle.
 
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