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Discussion Starter #1
I'm always interested in learning about other Bolt drivers' experiences with their BEV, particularly as they relate to range under various conditions. So, I thought that I would give back a little and provide my own experience with a recent day trip.

First, for those who just want the bottom line, here are the basic stats (with the source in parentheses) of the day trip I recently took:

Both directions:
Road: mostly interstate highways, some local roads at the endpoints
Terrain: flat
Weather: fair, low-80's to low-90's
Climate setting (Bolt): 72-73 degrees F, Fan speed 2-3

Destination trip:
Start estimated miles (Bolt): 248
End estimated miles (Bolt): 73
Actual distance traveled in miles (Bolt): 158.1
Energy used in kWh (Bolt): 41.2
Average miles/kWh (calculated): 3.8
Trip time (GPS): 2 hours, 37 minutes

Recharge:
Station: ChargePoint Level 2
Charge rate range in kW (ChargePoint): 5.7 - 5.9
Time (ChargePoint): 8 hours, 22 minutes
kWh added (ChargePoint): 46.3
Estimated miles added (ChargePoint): 154
Cost (ChargePoint): $16.19

Return trip:
Start estimated miles (Bolt): 228
End estimated miles (Bolt): 72
Actual distance traveled in miles (GPS): 160.6
Energy used in kWh (Bolt): 40.7
Average miles/kWh (calculated): 3.9
Trip time (estimated): 2 hours, 45 minutes


And now the (very long!) narrative:

Disclaimer: I am brand new to owning a BEV, so everything relayed here is from a total newbie! (Although one who has been researching EV's for several months.)

Our previous car that my wife and I replaced with the Bolt, a pre-owned 2013 Volt, gave us trouble-free service for the short (8 month) period we drove it, and no range anxiety due to the ICE generator on board. However, we took measure to get the best range we could to avoid using any gas. We typically achieved mid to high 40's miles in estimated battery range, due in part to a mild climate and conservative driving. And our typical commute rarely overran the battery. So, really, virtually any EV built in the last 6 years could have worked for our modest, local driving needs. But for longer trips, using gasoline was inevitable, either with the Volt or our "beater car" (Honda CR-V, which gets half the mpg as the Volt did but we need for towing, hauling, etc.). Our long-term goal has always been to be as fuel efficient as possible and reduce gasoline use (and subsequent tailpipe emissions), while staying practical to our driving needs. Further, we have a renewed desire to reduce our use of petroleum-based fuels, as our previous car to the Volt was a 2012 VW Golf TDI with the emissions issue(!) So, knowing that the Bolt would eliminate any tailpipe emissions *and* have enough range to get to fast charging stations outside our region meant these would be not only possible but more importantly practical. So, we traded in the Volt for the Bolt!

However, before embarking on a long trip, I wanted to test out the Bolt's range on a day trip under real world driving conditions to a destination far enough that recharging it would be necessary to get back home, requiring planning for various recharging scenarios. But not so far as to potentially becoming stranded and need rescuing! I also wanted to travel on a familiar route so that there would be as few surprises as possible along the way.

The planned route was Jacksonville, FL to Orlando, FL, specifically Disney Springs, an upscale outdoor mall with ample Level 2 chargers (courtesy of ChargePoint), and within short driving distance to multiple DC fast charging locations. This is a pretty straightforward drive, mostly involving I-95 and I-4, both of which have posted speeds of 65-70 mph. It would also involve some local roads driving, specifically at origin and destination, while also some congested highway driving (I'm looking at you, Orlando!). This part of Florida is largely flat, so no hill driving involved. The weather is fair but hot this time of year in Florida, so this would also been a good test of energy usage for climate control.

Regarding recharging, I wanted to make sure we had plenty of options, both at destination and in route. To make the connection process go smoother, I'd already signed up for ChargePoint (CP), Blink, EVgo, and Greenlots, whose charging stations collectively make up the bulk of in-network stations our my region. I also checked PlugShare for recent reviews on potential locations we might use. For the time being, northeast and central Florida along the I-95/I-4 corridor seem to have ample, generally available and well-rated charging stations, especially DC fast charging (mostly through EVgo).

With the Bolt fully charged overnight (using a ChargePoint Home 25 level 2 charger we had installed in our house last year in anticipation of purchasing the Bolt or some equivalent), we started out on a Saturday around 6:20am, in part to avoid a lot of traffic. (Hey, the car is brand new, and all those other cars make me nervous! ;) ) We drove around or a little below the posted speed limits, and while on I-95 mostly "caravaned" behind slower moving vehicles in the right lane to reduce initial energy usage and to avoid being buzzed by people driving much faster in the other lanes! Once on I-4, though, we drove at more typical (though still relatively conservative) highway speeds. Traffic was relatively light, even through Orlando, so not much stop-and-go on the way there as on previous trips, just the occasional slowdowns (and amazingly no accidents!). I know there are some complaints about the seats in the Bolt, and I am the first person to get uncomfortable, especially on long drives. (I had to use a seat cushion with the Golf as it was so uncomfortable, even after just a couple miles!) However, I found the driver seat comfortable, even by the end of the drive. Getting to the destination charging station was very easy. The exit off of I-4 and subsequent ramp to Disney Springs literally delivers you to what's called the Orange Garage. Drive up a couple flights to the roof, and the charging stations are at the back by the elevators. we arrived just before 9am, and two out of three EV spaces were available. (A Nissan Leaf beat us there! >:) ) Parked the Bolt and initiated a charging session with our ChargePoint RFID card. Piece of cake!

The Bolt provided an estimated recharge completion time of 5:30pm. So, we had about eight and a half hours in front of us. Naturally, there's plenty to do (and eat!) at Disney, so whiling away the day until the car recharged was no problem. I checked in with the CP app as well as the myChevrolet app to monitor charging progress during the day.

The Bolt actually completed charging around 5:00pm, earlier than estimated. Being mindful that an EV parking space is a functional space and not a place to just leave your car because it happens to be an EV ;) I wanted to make sure we were nearby the car should it complete early. Although we were elsewhere during much of the day, we stayed flexible and returned to Disney Springs in the early afternoon and hung around until CP indicated charging close to completed. Then we headed back to the parking garage and arrived at the Bolt right around when the charging was complete and disconnected to end the session. With the Bolt fully charged, we were ready to head home.

Out of curiosity, I recorded the battery level in real time while traveling to Disney Springs using a BlueDrive OBC2 diagnostic device. The iPhone app that BD provides is pretty slick and provides live data off the car, including elapsed time and temperature, along with battery life. Unfortunately, two of the most useful metrics of interest to me, car speed and distance traveled, are inexplicably unavailable from the Bolt. This is apparently not BD's fault, as the app can only capture and display the metrics that are supported by the specific car model. So, I had to use a separate GPS app (Cyclometer in this case, which I typically only use with running/bicycling). I plan to merge the two data sets together to produce a driving profile for that leg of the trip.

Interestingly, BlueDriver recorded 96.5% battery life at start and 34.9% at end, but these numbers indicate that 61.6% of the battery life was consumed which would translate to 37.0 kWh of the 60 kWh battery capacity was consumed, which is an under-report against the 41.2 kWh of actual energy consumed as reported by the Bolt. Does this fact, and the fact that the battery life at full charge only indicates 96.5%, suggest that Chevrolet is holding back some of the battery's capacity at the top and bottom of the charging range to increase battery life, as with the Volt? If I take that reported energy used by the Bolt, 41.2 kWh, and divide it by the BD-reported 61.6% battery life consumed, I get a total battery capacity of 66.9 kWh. The apparent "holdback" of 3.5% (100% - 96.5%) at reported full charge would calculate to be 2.3 kWh for the 66.9 KWh apparent total capacity, suggesting a 4.6 kWH (66.9 - 60 - 2.3) holdback at reported fully depleted battery. Does this make sense or am I reading too much into these numbers?

Anyway, all and all having done this trip, I am much more confident with the Bolt's range on long highway trips. I was worried that the miles/kWh would fall precipitously, leaving the Bolt with very little or no range on arrival, possibly requiring a recharge just to get to the destination. And then having to make multiple fast charging stops on the way back. But at 3.8-3.9 miles/kWh under real world conditions, there is only a small energy penalty for driving at higher speeds long distances. So instead of, say, 240 miles of range, it's more like 225 miles of range. I've noticed through PlugShare that most fast charging stations along the major routes I've looked at are 150-180 miles apart at most. So, the Bolt would still have 35-75 miles of range by each destination assuming full charge at start. That puts longer journeys in the realm of practicality (depending of course on charge station availability) by reducing the "long range anxiety"!

My next experiment will involve actually using a DC fast charging station when the battery is largely depleted to get a real world recharge rate experience. I may try this locally rather than on an actual trip, as how the battery was drained should be irrelevant. I'm interested to know the total recharge time, based on the condition of the battery at the start of the charge, as well as the charging profile. This will provide a sense of the additional time I will need to build in to the total trip time account for recharge times at fast charging stations for much longer, multi-state trips.

Wow, this has been an epic post! So, if you made it this far in the narrative, congratulations and cheers! :D I hope you find my experiences with long range driving with the Bolt useful.
 

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Always great to read road trip posts even if it is for a day trip and you're the kind of EV driver we all hope to come across with your impeccable charging etiquette.
 

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I have found with all my DCFC uses (3), that the charging "rate" inexorably declines. How many miles you add is dependent on the starting battery charge AND the duration of the charge. Most DCFC stations charge ($) by time, not by kWh added. Filling to "full (99%) on two of my DCFC experiences took 2 hrs and 15 minutes, starting at 10% battery (range indication ~ 30 miles) charge. The first 75 minutes took the charge from 10% to 80% (adding 175 miles) and the last 60 minutes filled that last 20% (adding 50 miles). Those 350 volts were pushing out 100 amps at start and 5 amps at shutoff. If this had been at a "pay" station, 5 30-minute sessions would have cost $50! Learning (planning) to arrive at a DCFC at a LOW, but "nerve-sparing" charge level and charging only enough to get to that next DCFC (or to home with that wonderful 30 amp Level 2 EVSE you installed) is the goal!
 

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Always great to read road trip posts even if it is for a day trip and you're the kind of EV driver we all hope to come across with your impeccable charging etiquette.
Thank you for your kind words! We actually became sensitized to charging etiquette even before we owned a PHEV or EV. ChargePoint put in a charging station right outside the building I work in early last year (which at least in part inspired me to get into EVs), and on the pavement in both charging spaces it is clearly marked "ELECTRIC VEHICLE CHARGING ONLY". The message could not have been clearer. And it just makes sense. Like the gas pump analogy I read recently. When you are done filling the tank, you put the nozzle back and move your car. You don't hog the pump position for the day!
 

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I have found with all my DCFC uses (3), that the charging "rate" inexorably declines. How many miles you add is dependent on the starting battery charge AND the duration of the charge. Most DCFC stations charge ($) by time, not by kWh added. Filling to "full (99%) on two of my DCFC experiences took 2 hrs and 15 minutes, starting at 10% battery (range indication ~ 30 miles) charge. The first 75 minutes took the charge from 10% to 80% (adding 175 miles) and the last 60 minutes filled that last 20% (adding 50 miles). Those 350 volts were pushing out 100 amps at start and 5 amps at shutoff. If this had been at a "pay" station, 5 30-minute sessions would have cost $50! Learning (planning) to arrive at a DCFC at a LOW, but "nerve-sparing" charge level and charging only enough to get to that next DCFC (or to home with that wonderful 30 amp Level 2 EVSE you installed) is the goal!
Thank you for your feedback on this! Based on your experience with DCFC, I can now understand why the 80% (and not 100%) target is desirable, from both a time and cost perspective. One and a half hours of charge gets you enough charge to get to the next station and a little beyond. The extra 45 minutes is not worth the little return in charge (unless you absolutely need it!)

I can also understand why if you want set up, say, an EVgo plan, you'd be better off going with their On-the-Go plan and not Flex if you do a lot of DCFC sessions. If you have Flex and so have paid only the one-time setup fee ($4.95), your per 30 min cost is the session fee ($4.95) + per minute fee (30 * $0.20) or $10.95. That would indeed be over $50 to top off the battery after five 30 min sessions. After nine of these five 30 min session sets, you are looking at about $500 total cost. By signing up for On-the-Go, however, you would be on the hook for $19.95 per month (or $239.40 for the year) plus the $0.20/minute of charging (no session fee). But the five 30 min sessions total cost would only be $30. At nine of these session sets, the total cost is also about $500. However, after that the total cost is lower for On-the-Go for the same number of sessions.
 

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Thank you for your kind words! We actually became sensitized to charging etiquette even before we owned a PHEV or EV. ChargePoint put in a charging station right outside the building I work in early last year (which at least in part inspired me to get into EVs), and on the pavement in both charging spaces it is clearly marked "ELECTRIC VEHICLE CHARGING ONLY". The message could not have been clearer. And it just makes sense. Like the gas pump analogy I read recently. When you are done filling the tank, you put the nozzle back and move your car. You don't hog the pump position for the day!
I bet if there was some ettiquette system in place where owners can rate other owners on things like this, it would correct a lot of behavior. Not fun to know your fellow EV owners find that you're a nuisance
 

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Interestingly, BlueDriver recorded 96.5% battery life at start and 34.9% at end, but these numbers indicate that 61.6% of the battery life was consumed which would translate to 37.0 kWh of the 60 kWh battery capacity was consumed, which is an under-report against the 41.2 kWh of actual energy consumed as reported by the Bolt. Does this fact, and the fact that the battery life at full charge only indicates 96.5%, suggest that Chevrolet is holding back some of the battery's capacity at the top and bottom of the charging range to increase battery life, as with the Volt? If I take that reported energy used by the Bolt, 41.2 kWh, and divide it by the BD-reported 61.6% battery life consumed, I get a total battery capacity of 66.9 kWh. The apparent "holdback" of 3.5% (100% - 96.5%) at reported full charge would calculate to be 2.3 kWh for the 66.9 KWh apparent total capacity, suggesting a 4.6 kWH (66.9 - 60 - 2.3) holdback at reported fully depleted battery. Does this make sense or am I reading too much into these numbers?
Yes, you've got this right. All EVs have an additional unusable buffer in the battery. Depending on who you ask, the full Bolt EV battery capacity might be between 66 and 70 kWh. I don't expect we'll ever know for sure, but the usable quantity (60kWh) is what matters for drivers.
 

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My next experiment will involve actually using a DC fast charging station when the battery is largely depleted to get a real world recharge rate experience. I may try this locally rather than on an actual trip, as how the battery was drained should be irrelevant. I'm interested to know the total recharge time, based on the condition of the battery at the start of the charge, as well as the charging profile. This will provide a sense of the additional time I will need to build in to the total trip time account for recharge times at fast charging stations for much longer, multi-state trips.
Here are some results from my Bolt EV battery charging models that may help you with trip planning. The graphs show four different DC fast charging rates, based on a maximum amperage of 60A, 100A, 125A, and 150A, which correspond to 24 kw, 40 kW, 50 kW and notional 60 kW DC fast chargers.

The models assume optimal conditions (car turned off, best battery and ambient temperatures) and can be summarized by this graph showing the power tapering as State of Charge increases.



Here are the plots for the 30 and 60 minute DC fast charge sessions. Note that highway range will be less.




Here is another plot showing how long it would take to charge from empty.



Some other relevant points to consider:
- All the miles in these graphs reference the EPA Combined range of 238 miles. Traveling faster than about 64 mph on the highway will reduce this rapidly. A 20% range hit occurs at 75 mph vs 64 mph.
- The advertised "90 miles in 30 minutes" is not possible, according to my models, with a 125A (50kW) or slower DC fast charger.
- The optimal starting SOC to get as many miles as possible from a 125A (50kW) charger is 17%. In this case, 30 minutes should yield a gain of 36% and end at 53% SOC, just before the first taper begins.
- The charge gained when starting at 50% SOC is basically the same as long as the charger is 100A (40kW) or greater.
- The difference between a 100A (40kW) and a 125A (50kW) is only significant when starting below about 40% SOC.
- The notional 150A Bolt EV charge capability, which is only speculative, has only minor effect on charge durations. The difference between 125A and 150A is only significant when charging for short durations and from low SOC.

Enjoy!
 

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For some reason, I always thought they would taper off around the same state of charge. But the first graph is really handy! Thanks for putting in the effort.
 

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Discussion Starter #10
Wow, thank you, Zoomit! This is a tremendous amount of great information! I've already started using it to plan out a long-range trip and am now expecting shorter charge times (and consequently short trip times) than I originally anticipated.
 

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Yes, you've got this right. All EVs have an additional unusable buffer in the battery. Depending on who you ask, the full Bolt EV battery capacity might be between 66 and 70 kWh. I don't expect we'll ever know for sure, but the usable quantity (60kWh) is what matters for drivers.
Cool, thanks! I hope this helps with long term battery life.
 
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