Bought a 2017 Bolt EV

[Isaac Zachary]

Looking at Plugshare, the places I was previously concerned about not having enough charging infrastructure now have enough charging infrastructure for me to consider an EV again, at least one with at least 200 miles of range.

That is, if I get an EV as an only car. There's a 30 mile range 2012 Leaf for sale here for $2,500 that I'm tempted to get. But I think I'll pass. Still, after a couple of years it could pay for itself in around-town fuel costs... Any thoughts?

[redpoint5]

Originally Posted by Isaac Zachary

That is, if I get an EV as an only car. There's a 30 mile range 2012 Leaf for sale here for $2,500 that I'm tempted to get. But I think I'll pass. Still, after a couple of years it could pay for itself in around-town fuel costs... Any thoughts?

How many bars does it have left? 30 miles doesn't say if that's winter or summer range. As you know, winter range could be half.

At some point, I expect battery degradation to fall off a cliff.

My parent's 2012 Leaf has about that much range. I'm still annoyed at my brother in-law for gifting them that because EVs are my expertise. He didn't consult me at all.

The Bolt is a solid platform. If it were me, I'd hold out for prices on used vehicles to fall. Probably plenty of people turning in vehicles when the recession hits full force and new car inventory builds.

[JSH]

In the past I've calculated charging efficiency for AC Level 1 and Level 2 charging. This week I let the car get low to do a full charge on DC. 40 degrees ambient temp, starting SOC 16%, ending SOC 100%. The car's max charge speed was only 22 kW. (The last Chevy battery update has kneecapped my DC charge speeds)

The Bolt used 53.4 kWh to drive 170 miles and took 55.013 kWh to get to 100% = 3% charging loss.

[redpoint5]

Cold temps capping the power?

I know one guy once barely made it to a DCFC in extremely cold weather, and the car told him he had to plug into L2 before DCFC to get the battery temperature up. He was stranded in the cold despite being at a charger. Apparently the car won't heat the battery using energy from DCFC.

[JSH]

Originally Posted by redpoint5

Cold temps capping the power?

I know one guy once barely made it to a DCFC in extremely cold weather, and the car told him he had to plug into L2 before DCFC to get the battery temperature up. He was stranded in the cold despite being at a charger. Apparently the car won't heat the battery using energy from DCFC.

That is what I'm reading - that 22 kW is about all we can expect at temps below 40F. Which is backwards to me. Cold weather is when DC charging is needed the most because the range drops to 200 miles.

The car will run the battery heaters while DC charging - I've seen that happen in the Torque app. I did read recently on the Bolt Forum that the car will charge faster in the cold when turned on - which sounds odd but I may give it a try.

I do have a new recall to do (Seat belt tensionor) so I'll have the dealership confirm charge speed and that all the correct software updates are done.

[redpoint5]

I don't understand why charging speed would be limited if it does heat the battery... I know Tesla's will preheat as you near a charging destination you've told it to navigate to.

Can you confirm the heater runs when the car is off while DCFC?

I figured the need for L2 in extreme cold was that the heater only ran when the contactors were closed, which is what happens when L2 charging.

[JSH]

Originally Posted by redpoint5

I don't understand why charging speed would be limited if it does heat the battery... I know Tesla's will preheat as you near a charging destination you've told it to navigate to.

Can you confirm the heater runs when the car is off while DCFC?

I figured the need for L2 in extreme cold was that the heater only ran when the contactors were closed, which is what happens when L2 charging.

Bolts do not have the option to precondition on the way to the charger.

I did another DC charge today. Starting battery SOC 20% and temp 58F. The charger (150 kW) started the charge at 21 kW. The battery heater went to max (2 kW) and the battery coolant pump to 95%. It stayed at 21 kW until the battery temp hit 75F and then the charge rate started to slowly ramp up. At 80F it hit 25 kW and kept climbing while the battery heater started to ramp down. (It looks like 80F is the target battery charge temp). Max charge rate I saw before my phone stopped recording was 31 kW at 37 SOC%. I let it charge for 2 hours and the SOC went from 20% to 95% in that time.

So GM is throttling charge speed at lower battery temps and the car will run the battery heater when plugged into a DC charger.

[redpoint5]

Then the charge rate tapers again just past 50% SOC. You may not have hit the full ~50 kW capability at any point.

[JSH]

Originally Posted by redpoint5

Then the charge rate tapers again just past 50% SOC. You may not have hit the full ~50 kW capability at any point.

Correct. With the replacement battery the taper starts even sooner - at about 45% SOC. With the slow ramp I doubt I ever hit 50 kW. I'll try to record a different section of the charge curve next week.

[JSH]

2023 Charging stats Jan - May (Each row is for the month before)

I still have the snow tires on because they didn't have enough tread for another winter. I just checked the tread depth and the tires are at 1.5 mm in the front and 2 mm in the rear so it is time to change back to summer tires.

I've also seen DC charge rates increase. Last week when the temp was about 70F the car jumped right up to 49.5 kW