Chevy Bolt - 200 mile range for $30k base price (after incentive)

[Jeff N]

Thanks, that helps a bit. It seems it peaks in power at 50% SOC, although it isn't that clear if that is the crossover point for peak current vs voltage.

What is with the jagged power cut after 50% SOC? Is that an artifact of the data gathering or is that actually how the BMS/charger is cutting current?

The DC chargers I mostly have used don't display detailed current and voltage data and neither does the Bolt EV. The 100A chargers from BTC do, so someday soon I will do a 15-100% charge on one of those and record the details. Basically, I think it starts off charging at the peak current (typically 100 or 125A today) and holds that until it reaches the low 50% SOC area. The graph shows the drop at around 52% but my experience was around 54% when I watched closely one day.

The jagged power cuts are actually what the Bolt EV BMS tells the charger to do. It seems rather primitive and I would have assumed a smoother rampdown in charging current but it is what it is.

 

[McRat]

That seems quite unrealistic. Even starting at 100%, arriving at 0%, and with a best-case 45kW charging rate for that hour, you'd have to beat the EPA-rated Wh/mi to make those 400 miles.

Realistically, it will be 2 charging stops, at least 75 minutes of charging, and another 10-20 minutes per stop wasted in getting from the freeway to the charger, plugging/unplugging, and getting back on the freeway. A better rule of thumb might be 1.5 hours if everything goes perfectly, and 2+ hours if its your first road trip or if there's any glitch along the way.

Yes, I'm assuming that if you have a 400 mile trip, you will drive conservatively, and that the Bolt EV will achieve the 90mi per 30min (or better) once the teething pains are over.

I'm not certain that 45kW is the peak charging rate on the 60kWh Bolt since that's what the 19kWh Spark EV can charge at.

Until this summer, nobody is probably going to know how fast the Bolt EV charges at.

ChargePoint Enables the Future of Mobility with Express Plus Electric Vehicle Charging Platform | ChargePoint

 

[jsmay311]

The jagged power cuts are actually what the Bolt EV BMS tells the charger to do. It seems rather primitive and I would have assumed a smoother rampdown in charging current but it is what it is.

"Primitive" is right.

As an engineer, that graph offends my sensibilities.

 

[csanders90D]

Yes, I'm assuming that if you have a 400 mile trip, you will drive conservatively, and that the Bolt EV will achieve the 90mi per 30min (or better) once the teething pains are over.

Driving conservatively would be an understatement. The EPA highway range on a Bolt is 217 miles (9% less than the combined cycle 238 miles). You would expect the two 90 mile charges to be used up 9% faster as well, making them effectively 82 mile charges. 217+82+82 = 381, still 19 miles short of your destination. Unless you beat the EPA highway cycle (which tops out around 60 MPH) by at least 5%.

So, add on an additional 1:20 for driving "conservatively" at 60 on the highway instead of keeping up with traffic at 75. You're wasting more time slowing down than you are by charging.

 

[Jeff N]

Here is a log of an actual trip rather than an idealized one. The first charging location along the way (Salinas) was chosen because it was a convenient location to add charge for driving to the 2nd charge location (San Luis Obispo) -- it was not ideal from a maximum charging rate point of view.

8:55am
Leave San Francisco
Odometer: 1242 miles
Estimated range: 237 miles
Battery: 100% full

11:20am
Arrive in Salinas
Odometer: 1351 miles
Estimated range: 148 miles
25.2 kWh to drive 108.9 miles
Segment: 231 Wh per mile from battery
Segment average speed: 45 mph
Battery: 58% full

Starting charge at 11:24am
Estimated 80% full in 24 minutes
Unplugged at 11:58am
Estimated range: 202 miles (added 54)

2:09pm
Arrived in San Luis Obispo
Odometer: 1482 miles
Estimated range: 58 miles
Cumulative total: 59.2 kWh for 239.5
Segment total: 34 kWh for 130.6 miles
Segment: 260 wh per mile from battery
Cumulative: 247 Wh per mile from battery
Segment average speed: 46 mph

Starting charge at 2:17pm
Battery at 23%
Estimated 80% complete by 3:20pm
Estimated to add 57% or 125 miles at 217
Unplugged at 3:23pm
Estimated range: 201 miles (added 143)

5:06pm
Arrived in Santa Barbara
Last 60 miles in heavy rain
Odometer: 1585 miles
Estimated range: 80 miles
Cumulative total: 87.7 kWh for 342.9 miles
Segment total: 28.5 kWh for 103.4 miles
Segment: 276 Wh per mile from battery
Cumulative: 256 Wh per mile from battery
Average segment speed: 35 mph

Total actual charging time: 90 minutes
Total trip time: 8 hours, 10 minutes

Actual freeway driving on US-101 was at the speed limit at 65-70 mph when not temporarily slower due to mild congestion near urban areas or the hour of driving in heavy rain near Santa Barbara. Average total drive time speeds are also lower because of driving in city streets leaving from home, to access charging stations, and driving city streets when arriving at destination. I used only seat heating, when necessary, plus the fan running at low speed and directed at the windshield.

Presumably, I could have driven another 57 miles beyond Santa Barbara in about an hour to reach 400 miles in about 9 hours of total trip time with the existing 90 minutes of DC charging during the trip.

At this point in my trip, I actually stopped for dinner and later added 30 more minutes of DC charge time along the way while driving to the Glendale area of Los Angeles where I ended my day of driving at around 440 miles. I forgot to keep detailed records after leaving Santa Barbara.

 

[Zoomit]

Thanks, that helps a bit. It seems it peaks in power at 50% SOC, although it isn't that clear if that is the crossover point for peak current vs voltage.

What is with the jagged power cut after 50% SOC? Is that an artifact of the data gathering or is that actually how the BMS/charger is cutting current?

Thanks Jeff for posting my Bolt EV model output, but I need to emphasize that the graphs are NOT of an actual charging cycle. I build the charging model based on early reports from Bolt EV owners.

So don't pay too close attention to the precise values, but certainly the major step-downs are real. Here's one source:

Here's a Facebook post with some good data but apparently suboptimal charge cycle: Elmec Inc. - REPRISE, avec l'ensemble des graphiques :... | Facebook

 

[csanders90D]

Total actual charging time: 90 minutes
Total trip time: 8 hours, 10 minutes

Wow, those charges are much slower than I expected, only averaging 31.6 kW. That's pretty bad for a station that claims 50kW on the label.

The Bolt can regen from braking at 60kW or more, so the battery and internal wiring must be able to handle it. Why would they handicap the CCS input so low?

Future 80 kW or higher chargers aren't going to make much difference if the Bolt is tapering below 40 kW when the battery is barely half full. It's almost like GM doesn't want to encourage higher speed EV charging.

 

[Zoomit]

That's pretty bad for a station that claims 50kW on the label.

Well, it is complicated. Of course it's not like just squeezing the handle on a gas pump to increase flow. The 50kW on the label is a reference to power output at 400V and 125A. If the battery is charging at less than 400V, then the power output has to be less. The Bolt EV has a nominal battery voltage around 350V. When charging at 350V, if the car allows 125A then the power will be 44kW [350V*125A].

The way I'd phrase the question is, why does the car limit the charging amperage so much above 50% SoC? You are absolutely correct that higher amperage charging stations, if the car was even able to accept higher amperage, would not greatly reduce recharge times because it would likely only increase the charging amperage when 1) the SoC is low and 2) the battery is at the appropriate temperature to accept the higher amperage.

The early charging taper on the Bolt EV creates some interesting results when comparing it to others cars over long distances. Assuming a sufficiently dense DCFC infrastructure, a more efficient and faster charging car like the Ioniq Electric could complete a 400+ mile trip faster than the Bolt EV, even considering it has half the range of the Bolt EV.

 

[Matias]

What do you think about PSA buying Opel. How will it affect Ampera e?

 

[TonyWilliams]

The general rule of thumb is you wake up with a full charge. So a 400 mile trip takes about 1 hr extra each direction for most 200+ mile EVs. Or 2 hours for 800 miles.

As stated in my article. If you are at home, a hotel, or grandma's house, please, fully charge the Bolt EV (or any EV) before embarking on a long journey.

Obviously, that is not available in every circumstance. Not every home has electricity at the vehicle location (condos, apartments / flats, etc), not every hotel has public charging available, and I'll bet grandma doesn't, either.

So, my comments concerning the best strategy for a long journey is charging for 30-60 minutes every 75-125 miles at only 125 amps or higherrated chargers, after arriving at each charger at 15% or lower, will maximize travel efficiency and minimize time.

 

[Jeff N]

Assuming a sufficiently dense DCFC infrastructure, a more efficient and faster charging car like the Ioniq Electric could complete a 400+ mile trip faster than the Bolt EV, even considering it has half the range of the Bolt EV.

Although it wouldn't be very practical since you probably wouldn't want to charge beyond 80% so that only gives you about 90-95 highway miles on a brand new battery pack with no degradation. Then you need to set aside 20-30 miles of reserve in case of unexpectedly poor efficiency (bad weather, etc.) or broken chargers that require diverting to another charge site. You end up having only about 65 miles of usable range between charging hops. The same accounting on a Bolt EV still leaves you with a much more realistic 130+ miles to use.

More hops means more wasted time getting off and back on the freeway. It also means more chances of having to wait for someone else to finish using the charger. So, at the end of the day the GM charging turtle and its much longer range may end up winning the race against the Hyundai rabbit.

 

[TonyWilliams]

This is obviously a lot slower than an S75 on a Supercharger. It will be interesting to see the rates for a Model 3 with a ~55 kWh pack.

All Tesla cars and ONLY the Hyundai Ioniq and Kia Soul EV are known to charge at 200 amps or above. All these cars have 400 volt batteries (plus or minus 5 volts) except small battery (40-60-70-75kWh) Tesla cars at 354 volts max:

45kW = 365v * 125a max charge rate (Bolt EV, typical of most modern non-Tesla cars)
50kW = 400v * 125a max charge rate (Tesla with biggest battery, 90-100kWh)
70kW = 350v * 200a max charge rate (Soul EV and Ioniq in Norway and few other EU locations)
115kW = 325v * 365a max charge rate (Tesla 70-75kWh on Supercharger)
115kW = 350v * 330a max charge rate (Tesla 85-100kWh on Supercharger)

Could a Bolt EV also charge at some value above 125 amps? There's no reason other than GM being conservative. I have a $100 bet with a Bolt EV owner that 125 amps is the maximum, and we intend to test that theory soon.

What might a Tesla Model 3 with a 55kWh battery charge at? Here's my guess:

100kW = 350v * 285a max charge rate (Tesla M3 w/ 55kWh on Supercharger)

 

[RobStark]

Very detailed interior review. Also high def exterior review. Not a road test review.

This is an ICEv guy not a BEV guy so cut him some slack.

Very positive on the Bolt overall though.

 

[Jeff N]

Pretty good "parking lot" review. He did miss the fact that the cargo floor that is even with the bottom of the hatch entrance is "false" and is just a cover that can be easily dropped down to the deeper floor underneath when you need more space.

 

[Zoomit]

Although it wouldn't be very practical since you probably wouldn't want to charge beyond 80% so that only gives you about 90-95 highway miles on a brand new battery pack with no degradation. Then you need to set aside 20-30 miles of reserve in case of unexpectedly poor efficiency (bad weather, etc.) or broken chargers that require diverting to another charge site. You end up having only about 65 miles of usable range between charging hops. The same accounting on a Bolt EV still leaves you with a much more realistic 130+ miles to use.

More hops means more wasted time getting off and back on the freeway. It also means more chances of having to wait for someone else to finish using the charger. So, at the end of the day the GM charging turtle and its much longer range may end up winning the race against the Hyundai rabbit.

You might be surprised at the results, given my caveat of a "sufficiently dense DCFC infrastructure". That mitigates the risk of broken chargers, waiting for other users, long drives away from the highway, etc.

There's no question that the Bolt EV's available range can provide more flexibility and confidence for long trips, verses shorter range cars like the Ioniq Electric, but it doesn't guarantee it will be the fastest. Naturally, the other question is whether anyone cares about a ~20 minute savings over an 8 hour journey.

My broader point is the Bolt EV's range doesn't necessarily translate into faster long distance trips when compared against the ~125mi BEVs currently or shortly on the market.

 

[TonyWilliams]

The DC chargers I mostly have used don't display detailed current and voltage data and neither does the Bolt EV. The 100A chargers from BTC do, so someday soon I will do a 15-100% charge on one of those and record the details. Basically, I think it starts off charging at the peak current (typically 100 or 125A today) and holds that until it reaches the low 50% SOC area. The graph shows the drop at around 52% but my experience was around 54% when I watched closely one day.

The jagged power cuts are actually what the Bolt EV BMS tells the charger to do. It seems rather primitive and I would have assumed a smoother rampdown in charging current but it is what it is.

All the BTC chargers are limited to 100 amps. Most of the others are 120 or 125 amps, except the ChargePoint CCS stand-alone units (now CHAdeMO plug at the station), those are 60 amps.

Yes, that BMS programming is quite crude. I know of no other car that does that. In the programming that we do for vehicles, we include a table for temperature control that acts similarly, but it is almost NEVER used:

125 amps - 10C to 44C cell temperature
90 amps - 45C to 46C
60 amps - 47C to 48C and 0C to 9C
30 amps - 49C to 50C and -20C to -1C
Shutoff --- 51C or -21C

 

[TonyWilliams]

So, add on an additional 1:20 for driving "conservatively" at 60 on the highway instead of keeping up with traffic at 75. You're wasting more time slowing down than you are by charging.

Yep... at least 1+20 wasted by driving slower. Check out the graph:

 

[WannabeOwner]

the other question is whether anyone cares about a ~20 minute savings over an 8 hour journey.

My wife does, but I don't know why. This on yesterday's 400 mile journey:

"It's terrible that we have to stop for 20 minutes"

"well, yes for you as a passenger it adds to travel time, for me as the driver its a break on a long journey"

The car is her daily-driver, and she never ventures 200+ miles unless I'm at the helm, so I continued:

"You've done 17,000 miles in 6 or 7 months. That's about 35 refuelling stops in your old (ICE) car, each time about 5 minutes - so that's 3 hours that you have saved and right now we're using some of that back up."

"No, they are only 5 minute stops, this is completely different" (or something like that, I'd started to tune out by then!)

 

[ItsNotAboutTheMoney]

My wife does, but I don't know why. This on yesterday's 400 mile journey:

"It's terrible that we have to stop for 20 minutes"

"well, yes for you as a passenger it adds to travel time, for me as the driver its a break on a long journey"

The car is her daily-driver, and she never ventures 200+ miles unless I'm at the helm, so I continued:

"You've done 17,000 miles in 6 or 7 months. That's about 35 refuelling stops in your old (ICE) car, each time about 5 minutes - so that's 3 hours that you have saved and right now we're using some of that back up."

"No, they are only 5 minute stops, this is completely different" (or something like that, I'd started to tune out by then!)

Does your wife put on make-up before an evening out?

 

[WannabeOwner]

Does your wife put on make-up before an evening out?

Hahaha ... that's priceless. She's not obsessed with makeup, so sadly not as big a WIN as it no doubt will be for others, but I'm going to dine-out-on-that-one nonetheless Thanks