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Why so slow?

19K views 60 replies 25 participants last post by  ElderGeek 
#1 ·
Went on a little trip through the Columbia River Gorge with my recently updated 'final' software, 2019 LT.

Plugged in at Electrify America (Gorge Outlets, Troutdale). With EngineLink showing battery Temp of 30C (I assume the sweet spot?). Battery Coolant temp 25C. Battery Coolant pump running at 4296 RPM. Bat. Coolant temp lowered to 18C.

SOC Raw was 44%, power slowly ramped up to 50kW. At 50% SOC, power delivery started going down. By 60% SOC, 32 kW, by 70% 23 kW. At 70% SOC, battery temp was up to 33C. Stopped charge at 70%.

Not impressed to say the least. Anyone have ideas on what the problem might be?

Definitely have 'charger envy' after watching Youtube Byorn Nyland plug in Model 3 SR+ which started charging at 140kW. Pretty much same battery capacity. So, Chevy/Generous Motors, why?
 
#4 ·
Sounds normal to me. All EVs slow down as state of charge increases, but the Bolt has a conservative charging curve. Post 3 in the link shows the curve.
 
#5 ·
Definitely have 'charger envy' after watching Youtube Byorn Nyland plug in Model 3 SR+ which started charging at 140kW. Pretty much same battery capacity. So, Chevy/Generous Motors, why?
I assume this was your first DC fast charge? The Tesla Model 3 is $10K more than the Bolt, and sells an order of magnitude more. Wonder why? ;)
 
#6 ·
Yeah, a decade or more of doing nothing but building electric vehicles is bound to get you ahead of the curve. It's still a valid question though: the Bolt is probably THE slowest charging mainstream EV built today. It is what it is. Back in 2016, it was OK because the charging infrastructure couldn't do any more than 50 kW. I am just disappointed that the 2022 didn't increase the charging speed. It seemed like a great opportunity (time) to do that. They'd really need to double the charging speed to make it competitive with the rest of the 2022 EV lineup.

Mike
 
#22 · (Edited)
Back in 2016, it was OK because the charging infrastructure couldn't do any more than 50 kW.
If I could plug-in and get 50kw from 10% SOC to 50% SOC every time, I'd be content with the Bolt, even for long road trips! What doesn't work for me is plugging-in below 40% SOC, pack temp 61F, and getting 32kw, because "brrr. 61F is too darned cold!" and the Bolt doesn't bother to heat the pack to optimum temp.
Looking at the thread on pack temp / SOC / charge rate
...you can see that if Chevy heated the pack to 35C, a 2020 Bolt would charge at its maximum rate of 150amps from 10% to almost 50%. That's acceptable (that would be 51kw @10% rising to 54kw at 50%, before the ramp-down). That's basically what the VW id.4 does: every time you turn it on, it heats the pack to "peak DCFC KW" temp. of 25C.

Would 35C harm the bolt's pack?... I don't know. If it does, then it could be made a temporary setting in infotainment (e.g. resets after 24 hours). Does that waste a bit of energy? Definitely. But on a car trip, I'm more concerned with fast charging. Around town, I'm unconcerned about either range or DCFC speed.
 
#9 ·
This constant demand for punishing a lithium battery with massive 2c -3c charging speeds. Sure it can be done, GM could allow 150kw charging speeds and then deal with the much faster degradation that it ALWAYS entails. The Bolt battery coolant design just isn’t capable of providing the consistent, even, cooling across the 288 cells that’s required to cram 150kw into a 66kwh battery. It was designed to be adequate for moderately fast charging and keep degradation in check. Get used to it.
 
#10 ·
This constant demand for punishing a lithium battery with massive 2c -3c charging speeds. Sure it can be done, GM could allow 150kw charging speeds and then deal with the much faster degradation that it ALWAYS entails. The Bolt battery coolant design just isn’t capable of providing the consistent, even, cooling across the 288 cells that’s required to cram 150kw into a 66kwh battery. It was designed to be adequate for moderately fast charging and keep degradation in check. Get used to it.
NO.

Dealt with the slow DCFC rate for my entire ownership without complaint, advocating the ability of the Bolt to make road trips with proper planning. I had planned on upgrading to the latest and greatest Bolt when the next generation came out in 2021 (delayed to 2022 by C-19) only to be given the big middle finger by GM with a continuation of the pathetic charging speed. Model Y Long Range is on order now instead of a second generation Bolt. We are keeping the Bolt as a local driving only car. Part of the reason for keeping the Bolt is that my wife is attached to the Bolt, but the logical reason is that the trade in value is crap compared to the real world value as a commuter car for my wife that will last the next 20 years with virtually zero maintenance and low operating cost. We had considered selling the Bolt and getting a Spark EV... but best case we could get 15K for the Bolt and a used Spark goes for 12K now, so trading down to a car with less than half the battery capacity made zero sense when the price difference is so small.

Keith
 
#11 ·
So to hopefully put this thread to bed...
1. No, not my first DC charging experience, but it was the first with the 'final fix'.
2. I did not note that the outside air temp was about 75F
3. The battery temp being 30C was right in the best spot for DC charging as far as I know.
4. It is what it is and I was overly optimistic about getting a faster DC charge rate with the update. At the end of the day, I only paid $21K for a new car. There is that part.
5. Good thing the charging network is constantly expanding. I will try to keep multiple charging stop trip distances below ~120 miles to make stops not tooooooo long.
6. And yes, I still have DC charging speed envy for all of the other EV's. Except for the latest Ioniq maybe.
Thanks for the input.
 
#18 ·
Once Ultium becomes available for 2023 model year, I would think GM would adapt the Bolt or replace it with a different model. Ultium battery is significantly cheaper than the Bolt packs. Probably a few thousanf dollars difference to GM per car.
 
#19 ·
I suspect Bolt won't get Ultium 1 until Ultium 2 rolls out (2025 or 2026?). I think their strategy will be N-1 for the economy segment, and latest tech for the premium models.

Their initial Ultium production will go towards higher margin Hummer, Lyriq, Silverado, and Honda\Acura. If they find a surplus, they may consider other models, but eventually they will retire BEV2 production and retool the BEV2 plants to produce Ultium cells, perhaps for the N-1 vintage. Their plants currently planned or being constructed probably won't have capacity for Bolt too. I would like to be proven wrong, but that is my guess.

Honda is likely developing their own platform, so the Ultium agreement may be short term to get their foot in the door. If so, surplus capacity would exist a few years down the road unless demand for premium models takes off like a rocket.
 
#25 ·
There's a lot of great info on this thread, I'd just add that don't judge the Bolt too harshly here. When you see advertised charging DCFC those are always peak speeds. Some people look at things like the ID.4 and Mach-E and are like, "omg wtf this thing charges 40 billion times faster" and it's just not true.

It's hard to explain but don't look at spec sheets when trying to figure DCFC speeds. Look at real world times spent at charging stations on things like abetterouteplanner. On that front you'll find the Bolt is obviously the slowest but really, it's only like 2x slower than the fastest charging cars out there, not as bad as it seems on paper.

I have a Bolt and a Kona EV. The Kona EV theoretically can charge 50% faster, that definitely does not translate to 50% less time at charging stations.
 
#26 ·
There's a lot of great info on this thread, I'd just add that don't judge the Bolt too harshly here. When you see advertised charging DCFC those are always peak speeds. Some people look at things like the ID.4 and Mach-E and are like, "omg wtf this thing charges 40 billion times faster" and it's just not true.

It's hard to explain but don't look at spec sheets when trying to figure DCFC speeds. Look at real world times spent at charging stations on things like abetterouteplanner. On that front you'll find the Bolt is obviously the slowest but really, it's only like 2x slower than the fastest charging cars out there, not as bad as it seems on paper.
It's pretty bad.

The 2020+ Bolts takes 68 minutes to go from 5-80%. The VW ID.4 takes ~35 minutes for the same. But the ID.4 is far from the fastest charging of the new vehicles. The Ioniq 5 does 5-80% in 20 minutes.

I have a Bolt and a Kona EV. The Kona EV theoretically can charge 50% faster, that definitely does not translate to 50% less time at charging stations.
The Kona EV theoretically supports 75kW charging. The Bolt 55kW. That's 36% faster. The Kona EV takes roughly 52 minutes vs. 68. That's around 30% faster. So no, theoretical speedup does pretty much match the actual speedup.
 
#34 ·
The Soviet implementation of economic life was a goddamn nightmare, no doubt about it, but in hindsight it's hard to fault them on their end results, things that the West could never do because of its market-leading need for its successful products.

Look at the AK-47 or the Soyuz rocket, automobiles are really the only place the USSR hasn't produced a worldwide staple that long outlasted its mother country.

Think about it, we could have bargain basement industrial items that never break and all we have to do is give up our right to eat and live.
 
#37 ·
automobiles are really the only place the USSR hasn't produced a worldwide staple that long outlasted its mother country.
Anything with electronics. 20 years ago I worked for a start-up company making a DNA analysis machine. It was started by a pair of Russian scientists (one of them married to a French financier). They needed to make the machine in the U.S. because electronics technology was 20+ years behind in Russia. Yet their material science was superior in Russia. I got called into the office and questioned about why I was using expensive aluminum for a bearing housing instead of something cheaper, like Titanium. Apparently aluminum was much more expensive in Russia but titanium was fairly cheap.

Side story: The Russian woman came into my office one day asking if I had any scotch. I was rather confused and thought that she was accusing me of having a bottle of alcohol in my desk. Turns out they just use the term "scotch" in place of scotch tape.
 
#48 ·
That is also my observation after the 80% limit software update, it looks to me the charge curve just shifted down 20%, the charge rates reflect what I saw before and after the update.
The rate I got previously before the update at 90% is now observed at 80%, what I got previously at 80% I now observe at 70% etc. Not ideal for sure, hopefully when I get the new battery and the final software update that restores 100% charging ability the curve will resort back or be better than what I had before the 80% charge software was installed.
 
#53 · (Edited)
Here is the thing. You can check it yourself on ABRP.
1. Bolt EV 2019 66 kWh upgrade (which I have)
2. Mustang Mach-E 2021 AWD
Trip to Toronto from Montreal = 545 km
Times :
  • Bolt EV : 6h29 with 45 mins charge
  • Mustang Mach-E : 6h08 with 25 mins charge

So, yes, the Bolt EV stayed more to the charger, but the difference of 20 mins isn’t worth 20k $ price difference. And ABRP is 10% off in what concerns the Bolt EV because they don’t have many Ampera-E in Europe. They consider the efficiency of the Bolt EV as 184 Wh/km at 110 km/h while my experience shows it is 168 Wh/km.

IF I input 168 Wh/km efficiency at 110 km/h in ABRP and leave the rest as is, guess what ? The time becomes 6h18 with a stop of 34 mins. <— This is a better approximation and it matches my experience.

So 10 mins between the two cars, for 20k $ more.
It’s not worth it for me and the infrastructure we have here to even consider any of the new EV.


Water resources Water Ecoregion Map World

Water resources Water Ecoregion Map World
 
#55 ·
You must be comparing a standard range Mach E, you did say it was AWD. That has lower range than the Mach E and lower charging speeds than the extended range battery.

ABRP is way off for my Mach E, I have a CA Route 1 with 305 miles of range, RWD and extended battery. I do not use ABRP for any route planning, but have compared it to actual trips. On my trip to Grand Canyon it told me I would arrive at my charger with 13%, in real life I arrived with 33%. That trip was 75 mph up a 6000 ft elevation change and I was getting 3.1 mile/kWh, or 270 miles of highway range under those conditions. My Bolt was lucky to get 170 miles with the older battery under the same conditions, but I could get 190 miles at 75mph on a flat road with no wind. So with the new battery, maybe 210 miles.

FYI, I have taken my Bolt Phoenix to Flagstaff with the old battery and ABRP told me I could not make it.
 
#56 ·
Either way, even with the RWD it’s only 3 mins faster VS AWD.
And don’t get me wrong, I am glad you have your Mach-E and enjoy it. I only say that I don’t see the benefit of me buying it to replace my Bolt EV. 13 mins difference don’t make up for 20 000 $ more, to me.

Map World Line Biome Screenshot

Water resources Ecoregion Map World Rectangle


And make no mistake, I know we can have better numbers than ABRP.
 
#60 ·
And make no mistake, I know we can have better numbers than ABRP.
To get the right consumption for ABRP, at least on flat roads, the Mach E Extended RWD needs to be set to 3.3mile/kWh, ABRP has it at 3.1. For that trip using my known consumption, 15 minutes is all that is needed for 10% margin at the end of the trip. ABRP still has issues compensating for terrain and speed greater than 65, it overestimates consumption in those cases. In Arizona we have 75 mph speed limits and many mountains. I have found my Ford and Chevy apps give better predictions.

I am willing to pay more for a car based on higher range and better charging. I like the Bolt also, but these two cars are not really competitors. My wife notices the charging time differences, she gets really impatient waiting. The first trip we took in the Mach E, after having the Bolt for 4 years, she said "that's it, we are done charging?" Happy wife = happy life. She is also not very tech savvy and doesn't even have any charging apps on her phone, With the Mach E she can plug in at EA charger and push the continue button. The Mach E is her car, I am getting an EV truck to replace the Bolt and my current GMC pickup. I need to be able to tow up to a 7000 lb trailer.
 
#58 ·
My Mach E is in between your Teslas, 15 minute charging in Kingman. On the way home I left Vegas at 80%, and only needed 10 minutes, since it is downhill to Phoenix. I did not log my times. I have never taken the Bolt to Vegas, but 58 minutes sounds right. I have done a round trip Phoenix to Tucson in the Bolt and charged for 45 minutes. That is also 300 miles, just like Vegas.

And the real downfall of the Bolt is that for that trip to Vegas, there are not 2 close enough chargers to make 2 shorter stops. Kingman is the only option and it is right in the middle.
 
#59 ·
ABRP's charging estimates are extremely inaccurate. For example, if I am going to stop at a 25kw dealer charger, I hand-edit the stop and plug-in 18kw into ABRP (because the charge will start at 17kw and end at 19kw). If stopping at a "50kw" charger, I'll try to estimate pack temp, and adjust to 43kw or so. Once every stop has been hand-edited for charging speed, the ABRP time estimate is pretty accurate.
 
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