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Well You can Google for Bolt Batteries. Slow at work so I just google What it is for the New part at this date. The lowest I have ever seen is 12 K$ USD. as of 7/2019 the price shows up as $12.4 K plus only $200 shipping (shipping of only $200 seems very cheap for such a heavy part).
https://www.google.com/shopping/pro...&ved=0ahUKEwiAioLswKXjAhVDAp0JHZPFDXYQ8wII5wI

I am hopeful that 6-8 years from now if I need a new pack I could pick one up with more KWH for a lower price. A lot can happen with battery tech and pricing in almost 10 years.
Thanks, this is good to see what appears at first look to be a list of straight answers on price (regardless of the exact price per kWh).
 

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My Bolt has 57,000 miles, more or less. I just rant it down to basically no power, then blasted the heater and air conditioner until both stopped working, which I assumed was the practical end of the battery. I got 56.1 kWh out of it. So if you assume 2kWh is held in reserve that's not too bad. If you assume you start a new Bolt with 60 kWh then it's a little disappointing. But I'll have to wait and see if there's more degradation between now and 100k, or if most of the degradation occurs in the first 50k miles.
4 kWh loss in 57,000 miles is in line with what Eric reported in the first post. 1% loss (0.6 kWh) for every ~8,000 miles.

I need to more thoroughly check, but I estimate I've lost 20% range on my 2012 plug-in Prius over the course of 85,000 miles, with 25,500 of those EV.
 

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..... I went through significant degradation on a leased Leaf in a hot climate. .......I have seen a degradation in useable kWh of what looks like about 10% (a bit hard for me to tell exactly, but roughly high 10s to about 9.6 kWh).
A Bolt EV is neither a Leaf nor a Volt.

Tracking battery degradation is by nature inexact, "bit hard to tell exactly". Its necessary to accumulate many data over a long period of time before conclusions can be drawn. Until we see very significant battery degradation at well over 100k miles, nothing can really be said. Given the winter range of a Bolt EV drops to at least 150 miles just because of the cold weather, we should be looking for that type of range over the summer before we really start panicking about battery degradation. Just measuring range is very variable, as I have shown in graphs a couple of times here. If range is so variable between 150 miles and 250 miles winter to summer, 40%!!!, how is it possible to precisely conclude a battery degradation of 5% or 10% over a period of a few months or even a year or two of driving?

Certainly, if I begin to NOT see > 200 mile range when fully charged in the height of summer, then I might start to be concerned, but meanwhile its fine. Right now I see >19X miles when in hilltop, so I am not even in the least worried. I attach a range graph from my Bolt EV over about a year or so. Note the high variability of the measurements, which are a function of driving conditions, season, HVAC use, and so on. Most of these measurements are in Hilltop charging to 80% or so. Once the odometer covers many years and over 100k miles a trend down may or may not be noticeable.
 

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A Bolt EV is neither a Leaf nor a Volt.

Tracking battery degradation is by nature inexact, "bit hard to tell exactly". Its necessary to accumulate many data over a long period of time before conclusions can be drawn. Until we see very significant battery degradation at well over 100k miles, nothing can really be said. Given the winter range of a Bolt EV drops to at least 150 miles just because of the cold weather, we should be looking for that type of range over the summer before we really start panicking about battery degradation. Just measuring range is very variable, as I have shown in graphs a couple of times here. If range is so variable between 150 miles and 250 miles winter to summer, 40%!!!, how is it possible to precisely conclude a battery degradation of 5% or 10% over a period of a few months or even a year or two of driving?

Certainly, if I begin to NOT see > 200 mile range when fully charged in the height of summer, then I might start to be concerned, but meanwhile its fine. Right now I see >19X miles when in hilltop, so I am not even in the least worried. I attach a range graph from my Bolt EV over about a year or so. Note the high variability of the measurements, which are a function of driving conditions, season, HVAC use, and so on. Most of these measurements are in Hilltop charging to 80% or so. Once the odometer covers many years and over 100k miles a trend down may or may not be noticeable.
It's true that my back-of-the-napkin calculations could be off, and this is why I erred (or tried to err) a bit on the conservative side in projecting my perceived kWh and range losses. Much (but not all) of the apparent recent drop in kWh displaying on my dash was sudden and occurred in the days and weeks after a GM prescribed procedure. It is known amongst some of the Volt drivers to cause a drop in usable kWh in some cases (but perhaps not others). It is quite unsettling, especially since I am still experiencing some of the occasional power loss that is also a known issue. Still, maybe the summertime heat is so extreme recently that they are exaggerating the degradation. Separately, I'm well aware of the ups and downs of seasonal range losses and gains. This was already taken into account. I will admit that apparently losing range on a vehicle into which I have put more money than any previous vehicle by far has been a bit upsetting, so maybe I am jumping a bit to a conclusion, but I doubt it, especially considering the propulsion power reduced message continues, once in awhile. Indeed hopefully my Volt will pull a rabbit out of the hat and somehow recover a kWh or so when it cools down a bit, or for some other reason.

Otherwise, let me please say:

- Basically, I was just trying to have a side conversation comparing some approximate notes with a fellow Volt driver. I don't intend to delay for years drawing prelim conclusions or having prelim discussions on the matter. If you want me to couch the conversation a bit more in qualifiers about my lack of data and the fact that I am approximating, I think I already tried to do that somewhat appropriately, but ok, I suppose it is of use to go over that we be careful about assigning range degradation numbers or conclusions.

- I haven't kept track of your conversations, but if you've been meticulously tracking your data, that's great.

- I suggest it might be a useful project for some of the Bolt drivers to band together and pool their data, or perhaps reach out to Plug In America or some other entity and see if they want to do it.

- Not so much just in response to your post here, but taking into account your post and quite a number of others from other people in this forum, I sure do run into a lot of posts here which err on the side of projecting a lack of knowledge onto the other person. [edit to say:] I think this is somewhat understandable, as we are all strangers to each other, and even when we sort of get to know someone's handle and associated knowledge-set, it can get confusing. At the same time, it is hard not to bristle at this. I guess it's just part of discussion in general.
 

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I've been optimizing my driving manner over the months. After having owned a Bolt for more than a year, the drivable range at full charge is about 10 to 20% better YoY despite observing a battery degradation of about 3 to 4% as measured by the OBD-II sensor readouts. Now that the habit is more or less settled though, I suppose I'll be able to get a rough "feel" of battery degradation by looking at the drivable range in the coming years.
 

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I've been optimizing my driving manner over the months. After having owned a Bolt for more than a year, the drivable range at full charge is about 10 to 20% better YoY despite observing a battery degradation of about 3 to 4% as measured by the OBD-II sensor readouts. Now that the habit is more or less settled though, I suppose I'll be able to get a rough "feel" of battery degradation by looking at the drivable range in the coming years.
My battery more or less stays in the "goldilocks" zone in that I charge to 88% hill top mode; my car then is at 75% while I'm at work for 8 hours. It's at 50% when I arrive home, and only begins to charge back to 88% between 2 and 6 am. In spite of being at 50-75 per cent for most of the day (kind of like a Volt's battery) I still have about the same degradation as others have experienced--just a curious observation.
 

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I had mentioned this link once before, but in case it is of use to a fresh set of eyes, awhile back I had cobbled together some of PIA's older charts on degradation, by permission.

http://jlaz.com/Files/2015_battery_pia/2015_PIA_battery_chart.html

Looking at it now, I put the charts for the Roadster, Model S and the Leaf.

I mention it here to reiterate that I think it would be interesting to see a similar chart for Bolt, or for that matter the Volt. (The Volt is more of a moot point because it is not to be made any more, but I suppose from a lesson-learning point of view, there would be some interesting old data points there.)
 

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4 kWh loss in 57,000 miles is in line with what Eric reported in the first post. 1% loss (0.6 kWh) for every ~8,000 miles.

I need to more thoroughly check, but I estimate I've lost 20% range on my 2012 plug-in Prius over the course of 85,000 miles, with 25,500 of those EV.
So If the degradation is linear Eric should have a 100 K mile video soon talking about 12-13% capacity loss.
 

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So If the degradation is linear Eric should have a 100 K mile video soon talking about 12-13% capacity loss.
From graphs I've seen on other EVs, I don't think it's linear. You seem to lose a chunk relatively quickly (like 5% in 20000 miles) and then it flattens out. My guess is 10% but I wouldn't be surprised if it's still in the 8% range and hasn't moved measurably at 100,000 miles given that there are other factors like a software update thrown in there.

Mike
 

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Third attempt at a reply the site update giving me a temp difficulty. The question had to do with which is "harder" and more "wasteful" on battery and energy use driving / charging 100+ degree F or subzero. I would think colder temps are easier for the pack temp mgmt system to deal with.
 

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Third attempt at a reply the site update giving me a temp difficulty. The question had to do with which is "harder" and more "wasteful" on battery and energy use driving / charging 100+ degree F or subzero. I would think colder temps are easier for the pack temp mgmt system to deal with.
That's a good question. For me, at least logically speaking, the answer isn't obvious. 100F is only about 30 degrees from optimal and it takes less energy to cool than heat. On the other hand, 0F is 70F degrees from optimal. So I'd lean toward believing cold temps are worse since the temperature range is larger in that direction.

Mike
 

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I would have thought the opposite just because the act of driving / charging generates some % of waste heat that ends up keeping the pack warmer than the outside. When its really hot outside it seams like You are "layering" a lot of heat for the system to deal with; Outside heat+More heat from driving+even more heat from charging. Seems like it's just more for the system to deal with.
 

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Well, warming the battery is no better than 100% efficient since it uses resistance heating (generates new heat). Cooling the pack can be 300% efficient since it uses a heat pump (moves existing heat). That's the reason people talk about wanting a heat pump heater option. It can be more than 100% efficient, and it should be easy to implement considering heating just reverses the direction that an AC unit operates, meaning most of the necessary heating equipment and cost is already sunk into the cooling system.

I've got no idea why they make AC only units actually. My house came with one, but why isn't it a heat pump? Should be a marginal extra cost to allow it to reverse and move heat indoors.
 

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Well, warming the battery is no better than 100% efficient since it uses resistance heating (generates new heat). Cooling the pack can be 300% efficient since it uses a heat pump (moves existing heat). That's the reason people talk about wanting a heat pump heater option. It can be more than 100% efficient, and it should be easy to implement considering heating just reverses the direction that an AC unit operates, meaning most of the necessary heating equipment and cost is already sunk into the cooling system.

I've got no idea why they make AC only units actually. My house came with one, but why isn't it a heat pump? Should be a marginal extra cost to allow it to reverse and move heat indoors.
I think it's a bit more complicated than that. After having a number of heat pumps over the years, one of the parts that tends to go bad is the reversing valve. In addition, they don't work very well in very cold conditions and you have to add extra components and/or programming to handle de-icing as ice can build up when heating in the winter. This likely adds extra cost.

Mike
 

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I'm no expert, so I'm eager to know why all AC units aren't reversible heat pumps. Icing can be resolved with something as cheap as a resistance heating element, or briefly running in cooling mode. Not sure if there's something special about evaporators and condensers that reverse roles... I guess in my mind I'm thinking maybe 10% more expensive to make an AC unit be reversible, but that's based on very little knowledge of what the extra expense would be. If the AC unit in the Bolt was $300, I'd be willing to pay $330 to have it be a heat pump...

The other complication might be when you need cabin heat, but battery cooling.
 

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This is my first post here due to registration issues. I took weeks for the issue to get resolved.

I recently bought a used 2017 Bolt LT. Currently at 35.2k miles and my estimated battery capacity from Torque is 58.6 kWh. Being a used car it's not possible to tell how the previous owner charged the car, however a loss of 2.33% is definitely acceptable. I do wish we had access to the charging history, assuming it's recorded.

Since the majority of my miles are in the city I will probably never charge over 85% which appears to extend the longevity of Li-ion batteries. I've used AccuBattery on my two year old Pixel XL smartphone and I am currently at 90% capacity. Sadly the app doesn't have the ability to stop the charge at 85% so over the past couple years at least 10% of the charges were over 90% which could explain the 10% loss.
 

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I do wish we had access to the charging history, assuming it's recorded.
I wonder if you can get a my.chevrolet.com account. Not sure how that works. When I download my charging history it appears to talk to the car for the data. Would think you might be able to get at least one year's worth of data.
 

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I'm no expert, so I'm eager to know why all AC units aren't reversible heat pumps. Icing can be resolved with something as cheap as a resistance heating element, or briefly running in cooling mode. Not sure if there's something special about evaporators and condensers that reverse roles... I guess in my mind I'm thinking maybe 10% more expensive to make an AC unit be reversible, but that's based on very little knowledge of what the extra expense would be. If the AC unit in the Bolt was $300, I'd be willing to pay $330 to have it be a heat pump...

The other complication might be when you need cabin heat, but battery cooling.
A few heat pump complications from someone that considers himself a heat pump advocate.

Capacity: the colder it gets the harder it is to keep up with the heat load as there is "less heat" outside to move inside and your heat loss is going up at the same time, Delta t, or the temperature difference between inside and outside. You basically need substantially more capacity for heating then you do for cooling the same space.

Defrost: you do need to reverse the cycle to defrost the heat exchanger that is outside. Heat pumps work great if your low temperature is 40° Fahrenheit, they struggle when it's just above freezing and raining, the coil ices up all the time and so you waste a lot of energy defrosting it. Meanwhile, you don't want the passengers to get cold so you have auxiliary heat which is basically electric resistive heat in an EV.

Defog: you use the air conditioner to dehumidify the air to defog the windows, at the same time you need heat so that again necessitates auxiliary electric resistive heat.

Cost: larger capacity system, larger components, more refrigerant, controllers and valves for defrost and reversing, it all adds up.

Weight: no big deal in a stationary application but in an EV every pound counts.

Living in the Northeast, I am not opposed to heat pumps in electric vehicles, it's just that it's not the slam dunk engineering trade that everybody seems to think it is.
 
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