GM Ultium/Equinox EV Good DCFC Performance after Software Updates

[dogememe]

These cars are notoriously mediocre at DC fast charging. I don't think you can read or watch a single review of one of these vehicles without someone complaining about it. The mainstream GM Ultium stuff (so, excluding their trucks with huge packs) has fairly low nominal voltage compared to competing vehicles and thus it takes a lot more amperage to achieve reasonable DCFC speeds. Although this car is advertised at 150kw DCFC you will NOT get that on a 150kw DCFC due to amperage limitations - but a 250kw or 350kw charger can deliver the advertised speeds.

Anyway, we previously had a 2024 Honda Prologue, and now we have this 2025 Equinox EV. From a technical standpoint, these vehicles have the same charging system and battery pack and should have basically the same charging performance.

But, in my time with the Prologue, DCFC was always... mediocre at best. It wasn't bad, it never disappointed me, but it was definitely not great. Now I have a 2025 Model 3 RWD Long Range and that thing is a road trip BEAST.

But, in the time since the Ultium vehicles came out, they have recieved many software updates and perhaps minor hardware tweaks. Since we've owned the Equinox EV, it has received multiple OTA updates. I don't think we have got any dealer installed updates (GM calls this vehicle wide programming or VWP) and while there must be some update available that we don't have (I checked and ours is still on Android 12, not Android 14 that some people have), it does have all applicable OTA updates installed.

But long story short, the other night I drove the Equinox EV for the first time and also got to DCFC it myself for the first time. And I was pleasantly surprised.

I arrived at the Tesla V3 Supercharger with 4% state of charge and used my Lectron adapter. The vehicle was driven about 5 minutes after sitting all day when I got to the charger, and I was not able to precondition (due to low state of charge). Outdoor temps were about 55F as displayed by the vehicle.

Within a minute the Equinox EV had ramped up to about 140kw and within another minute it got to 152kw and just sat there. I stopped charging at 30% because I didn't have far to go but I found this result very much acceptable. The Prologue would not have done this... it's been a while but I remember it would ramp up much slower, and often never reach the advertised DCFC speeds.

So, I believe the difference is software updates. If you have an Ultium vehicle, I'd say take it to the dealer and have VWP done (this should be free, GM covers it under the basic vehicle warranty)... but even the OTA updates do matter. And I wonder if they gave fully updated 2026 model year vehicles to car reviewers and had them do their testing again if the results and sentiment would be better? But as it stands most people probably read the reviews that are already out there and get discouraged.

It's funny, the next day I took my Tesla to a (V4) Supercharger. I preconditioned for about 10 minutes and arrived at about 30% state of charge. Outside temps were about the same. Yet it never got above 100kw of charging speed and said something about charging speed limited due to low battery temperature. So... Ultium isn't always slower than Tesla. lol.

 

[E365]

My Blazer EV had the same upgrade. 10-80% used to be about 38-40 minutes, and now after the latest group of OTA updates I’ve done 34 minutes at about 55F. I haven’t tested it in colder conditions yet - it might do it even faster than 34 minutes.

 

[dogememe]

My Blazer EV had the same upgrade. 10-80% used to be about 38-40 minutes, and now after the latest group of OTA updates I’ve done 34 minutes at about 55F. I haven’t tested it in colder conditions yet - it might do it even faster than 34 minutes.

Which flavor of Blazer EV do you have? RWD/SS which does 190kw max or FWD/AWD that does 150kw max?

Have you done any updates at dealer or just OTA?

 

[97prizm]

These cars are notoriously mediocre at DC fast charging. I don't think you can read or watch a single review of one of these vehicles without someone complaining about it. The mainstream GM Ultium stuff (so, excluding their trucks with huge packs) has fairly low nominal voltage compared to competing vehicles and thus it takes a lot more amperage to achieve reasonable DCFC speeds. Although this car is advertised at 150kw DCFC you will NOT get that on a 150kw DCFC due to amperage limitations - but a 250kw or 350kw charger can deliver the advertised speeds.

Anyway, we previously had a 2024 Honda Prologue, and now we have this 2025 Equinox EV. From a technical standpoint, these vehicles have the same charging system and battery pack and should have basically the same charging performance.

But, in my time with the Prologue, DCFC was always... mediocre at best. It wasn't bad, it never disappointed me, but it was definitely not great. Now I have a 2025 Model 3 RWD Long Range and that thing is a road trip BEAST.

But, in the time since the Ultium vehicles came out, they have recieved many software updates and perhaps minor hardware tweaks. Since we've owned the Equinox EV, it has received multiple OTA updates. I don't think we have got any dealer installed updates (GM calls this vehicle wide programming or VWP) and while there must be some update available that we don't have (I checked and ours is still on Android 12, not Android 14 that some people have), it does have all applicable OTA updates installed.

But long story short, the other night I drove the Equinox EV for the first time and also got to DCFC it myself for the first time. And I was pleasantly surprised.

I arrived at the Tesla V3 Supercharger with 4% state of charge and used my Lectron adapter. The vehicle was driven about 5 minutes after sitting all day when I got to the charger, and I was not able to precondition (due to low state of charge). Outdoor temps were about 55F as displayed by the vehicle.

Within a minute the Equinox EV had ramped up to about 140kw and within another minute it got to 152kw and just sat there. I stopped charging at 30% because I didn't have far to go but I found this result very much acceptable. The Prologue would not have done this... it's been a while but I remember it would ramp up much slower, and often never reach the advertised DCFC speeds.

So, I believe the difference is software updates. If you have an Ultium vehicle, I'd say take it to the dealer and have VWP done (this should be free, GM covers it under the basic vehicle warranty)... but even the OTA updates do matter. And I wonder if they gave fully updated 2026 model year vehicles to car reviewers and had them do their testing again if the results and sentiment would be better? But as it stands most people probably read the reviews that are already out there and get discouraged.

It's funny, the next day I took my Tesla to a (V4) Supercharger. I preconditioned for about 10 minutes and arrived at about 30% state of charge. Outside temps were about the same. Yet it never got above 100kw of charging speed and said something about charging speed limited due to low battery temperature. So... Ultium isn't always slower than Tesla. lol.

What about using 800v charging? Tesla has fallen behind in that substantially. I think all Porsche models use 800v as well as Lucid. Lucid has the fastest charging out there.

 

[dogememe]

What about using 800v charging? Tesla has fallen behind in that substantially. I think all Porsche models use 800v as well as Lucid. Lucid has the fastest charging out there.

From my understanding higher voltage is ultimately better in terms of faster charging and overall efficiency.

That said, I have taken road trips in the Tesla and despite only being like what, 350V nominal, the car did great. Charging speeds were excellent, and the car generally outlasted our need for bathroom breaks and snacks.

So yes, while a higher voltage car might be better, I'm perfectly happy with the car the way it is and while they might be behind in terms of numbers on the spec sheet they aren't really behind in the real world in the way people actually use these cars. Battery pack voltage sure doesn't matter when it's plugged in at home into a 120V outlet LOL.

 

[E365]

Which flavor of Blazer EV do you have? RWD/SS which does 190kw max or FWD/AWD that does 150kw max?

Have you done any updates at dealer or just OTA?

Sorry, I should have mentioned that. It’s the 85kWh RS AWD with 150kW max.

I had a big dealer VWP (Vehicle Wide Programming) update done about 1 year ago and numerous OTAs since then. Not exactly sure when the charging curve improved, but I think numerous OTAs since my VWP have mentioned charging improvements.

 

[jghall00]

From my understanding higher voltage is ultimately better in terms of faster charging and overall efficiency.

That said, I have taken road trips in the Tesla and despite only being like what, 350V nominal, the car did great. Charging speeds were excellent, and the car generally outlasted our need for bathroom breaks and snacks.

Higher voltage means less current, which in turn means less heat buildup in the charging system and powertrain, and smaller diameter wires. So yes, 800V is faster, but it also comes with an additional cost that many manufacturers have not been willing to bear.

Tesla does well with 400V because their cars are efficient, which is the other side of the charging coin. You can get by with slower charging if the car doesn't use as much energy to operate. For many vehicles, it's perhaps a 10 - 15 minute difference. We're talking 20 minutes for, as an example, EGMP vehicles, vs 30 minutes for Tesla, and the Tesla is more efficient. Tesla also has robust 400V infrastructure, so moving to 800V doesn't provide a massive improvement, unless you're towing.

The difference grows with more efficient vehicles, like the Lucid Air sedan or Porsche Taycan, but then you're dealing with substantially higher acquisition costs and potentially limited 800V infrastructure. So for many, the juice isn't worth the squeeze because it only matters for public charging stops, which comprise a relatively small part of overall mileage for most drivers. Basically, 800V mostly benefits those who road trip or tow long distances frequently, which most people don't do.

Anecdotally, our longest drive in the Blazer EV has been 3 charging stops and ~800 miles, so faster charging would have cut perhaps 15 minutes per stop.

 

[UncleDave]

Faster on paper, and faster in the real world have been proven to be very different things in the world of fast charging.

 

[dogememe]

Faster on paper, and faster in the real world have been proven to be very different things in the world of fast charging.

And I’d say 80% of people rarely even fast charge? For all the talk about road trips most people do that… once a year?

I guess I really made this thread to demonstrate that GMs night not be the greatest for charging speeds but it’s plenty good enough for most people and that it’s great that OEMs can improve cars via software alone.

 

[jghall00]

Faster on paper, and faster in the real world have been proven to be very different things in the world of fast charging.

Here are some real-world tests.

Lucid Gravity: 10 to 80 < 25 minutes
Porsche Taycan: 10 to 80 < 20 minutes
Ioniq 6: 10 to 80 < 20 minutes
BYD: - 6 to 70 < 7 minutes

It's real.

 

[dogememe]

Here are some real-world tests.

Lucid Gravity: 10 to 80 < 25 minutes
Porsche Taycan: 10 to 80 < 20 minutes
Ioniq 6: 10 to 80 < 20 minutes
BYD: - 6 to 70 < 7 minutes

It's real.

Ok but we should also keep in mind battery size and vehicle efficient. I think miles/minute is what matters.

Also hard to compare a $100K Gravity or $150K Taycan to a $40K Equinox EV or Model 3

 

[jghall00]

Ok but we should also keep in mind battery size and vehicle efficient. I think miles/minute is what matters.

You're correct re: miles/minute, but this is already a selection of various vehicle types. The Gravity is a spacious, seven-seat SUV. The Taycan, Ioniq, and BYD are all sedans. The five-seat Porsche Cayenne matches the Taycan's charging speed. The links have the breakdown of miles added for each apart from the BYD. It's over 200 miles for all of them for the charge times listed. All of these vehicles are comparatively efficient, but it somewhat goes out the window with charging this fast because you can recoup miles faster than you expend them, so if you're ok with the 80% charge time you don't need to slow down. The EV9 can regain 200 miles in 25 minutes of charging. That too, is a seven seat SUV. The Silverado EV can match the Kia in miles added and it's a very inefficient truck. And this is what's available right now. The tech and infrastructure continue to improve.

Also hard to compare a $100K Gravity or $150K Taycan to a $40K Equinox EV or Model 3

That's specifically why I included the Ioniq 6. All of the EGMP vehicles have similar charging performance.

 

[UncleDave]

Here are some real-world tests.

Lucid Gravity: 10 to 80 < 25 minutes
Porsche Taycan: 10 to 80 < 20 minutes
Ioniq 6: 10 to 80 < 20 minutes
BYD: - 6 to 70 < 7 minutes

It's real.

Partial charging time tests are meaningless without distance traveled, and vehicle efficiency comparisons.

Battery size also plays into charging time, so that isnt a level playing field between models.

Out of Spec Reviews and Bjorn Nyland do a great job of this actually road tripping the cars and timing the results. I've already posted a few of these comparisons in this forum.

The gravity charges exceptionally well, but missed its mileage rating claim by a fairly significant amount.
Also greater than an 800 volt vehicle.

 

[Torrid]

What about using 800v charging? Tesla has fallen behind in that substantially. I think all Porsche models use 800v as well as Lucid. Lucid has the fastest charging out there.

800v charging sounds great, but it's so few and far between it's a bit of a nothing burger at this point. Would I prefer it? Sure. It's just not widely available and there isn't a car in my price range that I like with 800v architecture.

 

[jghall00]

Partial charging time tests are meaningless without distance traveled, and vehicle efficiency comparisons.

True. I just posted those numbers to show what is attainable with stops under 25 minutes on many available models since charging times seem to be a common complaint.

The gravity charges exceptionally well, but missed its mileage rating claim by a fairly significant amount.
Also greater than an 800 volt vehicle.

The Gravity came close to its rated range while traveling at 70 mph in the last State of Charge test. It appears that cold weather and a drive unit issue impacted the first test. The 450 mile rating that many outlets repeat is based on mixed driving anyway. It's actually rated around 370 miles using the highway consumption numbers.

 

[UncleDave]

True. I just posted those numbers to show what is attainable with stops under 25 minutes on many available models since charging times seem to be a common complaint.

The Gravity came close to its rated range while traveling at 70 mph in the last State of Charge test. It appears that cold weather and a drive unit issue impacted the first test. The 450 mile rating that many outlets repeat is based on mixed driving anyway. It's actually rated around 370 miles using the highway consumption numbers.

I started a thread on the gravity a few months ago.
I like the rig, but it seems to have electronic problems.
Good to know it redeemed itself 400 at 70 is pretty decent.

 

[E365]

800v charging sounds great, but it's so few and far between it's a bit of a nothing burger at this point. Would I prefer it? Sure. It's just not widely available and there isn't a car in my price range that I like with 800v architecture.

They actually are very common. Basically every DC Fast charger installed in the past 5+ years (that isn’t made by Tesla) is capable of outputting up to 920v. That’s essentially the minimum (max) voltage for the CCS1 standard. 950v and 1,000v max are also common.

For example, here’s a placard on the common ABB Terra 184. 200v - 920v CCS1 output.

Alpitronic HYC400s (IONNA, Walmart, MB HPC, etc.) are 150v - 1,000v
EA’s SK Signets are 150v - 920v

 

[Torrid]

They actually are very common. Basically every DC Fast charger installed in the past 5+ years (that isn’t made by Tesla) is capable of outputting up to 920v. That’s essentially the minimum (max) voltage for the CCS1 standard. 950v and 1,000v max are also common.

For example, here’s a placard on the common ABB Terra 184. 200v - 920v CCS1 output.

View attachment 318687

Alpitronic HYC400s (IONNA, Walmart, MB HPC, etc.) are 150v - 1,000v
EA’s SK Signets are 150v - 920v

There aren't many here that aren't made by Tesla, hence why I didn't pursue the Ioniq 5N like I at one time wanted. At the time there were only two within 50 miles in either direction that were 800v+ 350kW.

This is where most say that EVs don't work in the middle of the country because of public charging options. Tesla definitely invested enough it it to work, but there's still not a lot. I've never had an issue, but before Tesla was allowing non Teslas to use their chargers it might have caused me some issues. Even then my closest Tesla Supercharger is 30 miles away.

Now the other chargers you've mentioned, Ionna opened one location 65 miles south from here last month. I don't think there's any Walmarts in my area that even have charging aside from one of the 800v 350kWs I mentioned earlier and that is an EA station.

 

[jghall00]

There aren't many here that aren't made by Tesla, hence why I didn't pursue the Ioniq 5N like I at one time wanted. At the time there were only two within 50 miles in either direction that were 800v+ 350kW.

This is where most say that EVs don't work in the middle of the country because of public charging options. Tesla definitely invested enough it it to work, but there's still not a lot. I've never had an issue, but before Tesla was allowing non Teslas to use their chargers it might have caused me some issues. Even then my closest Tesla Supercharger is 30 miles away.

Local chargers aren't the ones you need to be concerned with unless you can't charge at home. In that case I would advise against an EV anyway. The most important consideration is whether there are chargers away from home on the routes that you travel. In 2020 my daughter attended school in northern New Mexico. Due to a lack of chargers away from major interstates, it was actually impossible to make the trip there from Houston, even with a Tesla, without a multi-hour diversion. The stretch from Sweetwater through Santa Rosa had no fast chargers above 23 kW. That's no longer the case due to improved infrastructure and range. Back then I had a Focus EV for local use. There were plenty of chargers in my area (it only had 100 miles of range). But I still only used them two or three times a month. We often had weekends where we traveled 50+ miles for softball. Now I never use them because my car has over 300 miles of range and all my local charging is done at home.