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My ’17 Volt show zero miles left on the battery when my info screen shows 14 Kw used.
I thought the bat was a 17 Kw one.
 

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only 14 are usable. GM utilizes a buffer at both ends to protect the battery.
 

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only 14 are usable. GM utilizes a buffer at both ends to protect the battery.
damn,that extra 4Kw's would get me 16-20 extra miles.
 

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Bill, I think the 2017 Volts have 18.4 kWh pack capacity in total, but only 14 kWh is usable. It is possible that late in the Gen II Volts life the software will allow the Volt access to the extra capacity, but regardless of that, the pack will last a LOT LONGER by having capacity that is never accessed either on the top or bottom of the typical charge cycle. You may wish you could use the extra kWh's now, but in 5 or 6 years it is possible that any Volt that had unlimited access to all its capacity may end up with early pack degradation due to the deeper cycles.
There is no way to know how many packs would degrade faster in advance, so GM's engineers played it safe and had big cushions of pack capacity built into the charge cycle.
The upside is that you 2017 Volt will probably still have nearly the same AER in 12 to 15 years. And it may have pretty decent range in 20 years.
On a similar note, I never liked it when my Mom told me to eat my vegetables first before I ate my dessert but it was probably better for me to do so. ;-)


damn,that extra 4Kw's would get me 16-20 extra miles.
 

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Nissan didn't protect the battery in the early Leafs and ended up having to warranty replace a large percentage of them. With LiOn batteries you don't want to fully charge or discharge them.
 

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Yes as others have stated the 2017 Volt's battery pack is 18.4KWh total with 14KWh usable (for EV operation).

Keep in mind that does NOT mean that the other 4.4KWh are totally unused. The Volt also reserves a buffer for hybrid vehicle operation (charge sustain mode). This buffer is likely close to ~1KWh. Also the Volt has a "turtle mode". That if you run out of EV range and gas the car will dig even deeper into the battery to give you a bit of range to make it to a charge station or gas station. So you can't compare the EV battery usage of a Volt to a BEV as the Volt's battery is used for more than just EV operation.

Also no EV uses 100% of the battery. That would accelerate battery degradation.
 

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To add:

If an EV battery charges up to 100%, you do not have significant regen immediately after charging.
It needs to have room up top.

But it's mostly needed for the Magic Trick that normal PHEVs can't do. Which is provide peak instant HP when the battery is 'empty'.
Your gas generator engine is only 101 HP. But even when your battery is drained, you have 161 HP (120kW) on tap.

The problem happens when it first has to switch to the gasoline engine especially up steep grades. Your battery is 'empty' and the ICE engine needs to warm up some before it is useful. At 0 miles on your EV meter, the Volt will produce full instant power.

If it didn't have this buffer, it would drive like normal PHEVs. That is, like crap. Sometimes you hit the accelerator and it takes off, other times, it bogs. And you don't always know which will happen. Weak electric motors, combined with small EV batteries and the nature of ICE engine powerbands conspire to keep you guessing.

Some see the 4.4kWh buffer as a waste. But without it, the Volt would act less like an EV and more like a gas car or hybrid. The Volt powertrain is still unmatched after 7 years.
 

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To add:

If an EV battery charges up to 100%, you do not have significant regen immediately after charging.
It needs to have room up top.

But it's mostly needed for the Magic Trick that normal PHEVs can't do. Which is provide peak instant HP when the battery is 'empty'.
Your gas generator engine is only 101 HP. But even when your battery is drained, you have 161 HP (120kW) on tap.

The problem happens when it first has to switch to the gasoline engine especially up steep grades. Your battery is 'empty' and the ICE engine needs to warm up some before it is useful. At 0 miles on your EV meter, the Volt will produce full instant power.

If it didn't have this buffer, it would drive like normal PHEVs. That is, like crap. Sometimes you hit the accelerator and it takes off, other times, it bogs. And you don't always know which will happen. Weak electric motors, combined with small EV batteries and the nature of ICE engine powerbands conspire to keep you guessing.

Some see the 4.4kWh buffer as a waste. But without it, the Volt would act less like an EV and more like a gas car or hybrid. The Volt powertrain is still unmatched after 7 years.
Where's the bloody "Like" button on this forum. This is probably the single biggest reason the Volt drives like an EV even when running ICE.
 

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It's been a few years since I've done it but, if I recall correctly, when you file your taxes, they ask for your car's battery capacity to determine how much your tax credit is. I believe 18.4 kWh should be used. It shouldn't matter though, because I've read the Volt far exceeds their threshold for the $7,500 max credit. Can anyone confirm how the tax credit is handled now? Didn't mean to hijack this thread.

I also agree about the above post being a need for a like button.
 

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Where's the bloody "Like" button on this forum. This is probably the single biggest reason the Volt drives like an EV even when running ICE.
Yup, yup, yup. :D
 

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Bill, I think the 2017 Volts have 18.4 kWh pack capacity in total, but only 14 kWh is usable. It is possible that late in the Gen II Volts life the software will allow the Volt access to the extra capacity, but regardless of that, the pack will last a LOT LONGER by having capacity that is never accessed either on the top or bottom of the typical charge cycle. You may wish you could use the extra kWh's now, but in 5 or 6 years it is possible that any Volt that had unlimited access to all its capacity may end up with early pack degradation due to the deeper cycles.
There is no way to know how many packs would degrade faster in advance, so GM's engineers played it safe and had big cushions of pack capacity built into the charge cycle.
The upside is that you 2017 Volt will probably still have nearly the same AER in 12 to 15 years. And it may have pretty decent range in 20 years.
On a similar note, I never liked it when my Mom told me to eat my vegetables first before I ate my dessert but it was probably better for me to do so. ;-)
Is there more information on the additional ~4 kWh that might be obtainable (at some point through software)? Would like to see GM say that they might consider allowing greater access to those extra 4 kWh. I understand that some of those extra 4 kWh might be accessible but not all. Have they done this/considered this with the Gen 1 Volts? thanks
 

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Part of that buffer will never be available since the battery never charges to 100% of it's total capacity. On the Gen 1 with a full charge, it only charges to 85% total capacity which should be in the neighborhood of about 13.5-14kWh out of the total of 16-16.5 (depending on year). The lower end of the battery retains about another 15-17% which can be accessed either when power demand exceeds what the engine can produce, or as an emergency range of a couple miles in the event you have depleted your normal EV range and no longer have the use of engine, usually due to running out of gas. Although it would be nice to be able to access the buffer to be able to tap into that extra range as needed if you only needed to go another mile or two, I can definitely see how for the most part that is a unique need that most people would not necessarily need. On the other hand, as we all know, there are ways to increase AER through driving style, conditions, tire pressure, etc. Perhaps there may be some changes you can make either in one or more areas to gain the necessary additional range to avoid needing to run the ICE.

I find I have more than enough range for my daily needs, and when the ICE does have to run, it's well out of range that even 100% use of my Gen 1 battery would be capable of providing, and in many cases would need to have a Bolt sized battery or larger.
 
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