My GT DCFC charging experience

[Shane_SLC]

I have a question that I hope someone can help me with…I use EA Fast DC chargers near my home. They are very reliable. However, I have never seen anything near 350 output, it normally begins charging at about 150-200. It drops rapidly after that. But I’m still OK with it. My question is: I use these fast charging DC units almost exclusivey. I haven't installed a home charger, yet. I read that fast charging is bad for the battery life. I find that my driving usage is such that I don’t need a home charger and I want to take advantage of the free charging which was included in my purchase. Am I damaging my batteries by using the Fast DC chargers? How often should I use a slower/AC charging method? (I use a 50AMP 240Volt Lucid charger at my second home, it works great. I just don’t use it often).
Thanks.

Getting charging speeds about 250kW requires a very specific set of conditions that you won't often meet unless you're specifically trying for it, and even then the charging infrastructure will likely be the limiting factor. For those that drive their EVs often day-to-day I'd say having a home charging option is almost mandatory. It makes the ownership experience significantly easier not having to hassle with crowded or poorly maintained fast chargers.

While saying fast charging "damages" the battery might be a bit of a stretch, it certainly stresses the battery cells and cooling systems more. Repeated and prolonged fast charging will likely degrade your battery faster, but it's difficult to say by how much. It may only reduce capacity by a few percent over a multi-year period, but it'll be unique to each car and it's battery management capabilities. If you want the most longevity out of your own battery pack I'd suggest setting up a home charger. If you only plan on keeping the car a few years, then fast charging as your default is probably not a huge deal if you feel it's not a hassle. Being able to charge at home will certainly save you time in the long run, if nothing else.

 

[REHPortland]

Thanks for the rapid replies…I live in a condo. I need to deal with the HOA and its complicated and expensive…eventually I will install one. I think that I have the answer to my question. (Maybe it’s bad, maybe not so much). My circumstances have worked well with very few issues. I love the car and hope the company survives. I bought LUCID stock a few years ago…yikes! Oh well. I’m going to check out the Gravity, when/if it finds the market.

 

[BS8899]

Thanks for the rapid replies…I live in a condo. I need to deal with the HOA and its complicated and expensive…eventually I will install one. I think that I have the answer to my question. (Maybe it’s bad, maybe not so much). My circumstances have worked well with very few issues. I love the car and hope the company survives. I bought LUCID stock a few years ago…yikes! Oh well. I’m going to check out the Gravity, when/if it finds the market.

I am no expert on lithium batteries. Here is an article that might shed some light.

BU-409: Charging Lithium-ion

BU meta description needed...

batteryuniversity.com

In my mind, there are probably two separate issues:
>

 

[BS8899]

I am no expert on lithium batteries. Here is an article that might shed some light.

BU-409: Charging Lithium-ion

BU meta description needed...

batteryuniversity.com

In my mind, there are probably two separate issues:
>

[1] Fast Charging...likely to causing temperature rise in the battery.
[2] "Over-Charging" can cause anode degradation

See the attached linked article.

 

[kort6776]

I have a question that I hope someone can help me with…I use EA Fast DC chargers near my home. They are very reliable. However, I have never seen anything near 350 output, it normally begins charging at about 150-200. It drops rapidly after that. But I’m still OK with it. My question is: I use these fast charging DC units almost exclusivey. I haven't installed a home charger, yet. I read that fast charging is bad for the battery life. I find that my driving usage is such that I don’t need a home charger and I want to take advantage of the free charging which was included in my purchase. Am I damaging my batteries by using the Fast DC chargers? How often should I use a slower/AC charging method? (I use a 50AMP 240Volt Lucid charger at my second home, it works great. I just don’t use it often).
Thanks.

I can't speak for Lucid but other EVs that I've owned, tesla, porsche, jaguar all say that excessive DC fast charging is not battery healthy.
I don't know where you live and rates you pay for power but I drive 10k miles per year and my power bills are only $20-40 higher from charging my two EVS.
it is worth it not to waste time charging at a public charger, charging the cars at home while I am sleeping is so much better.

 

[BS8899]

I can't speak for Lucid but other EVs that I've owned, tesla, porsche, jaguar all say that excessive DC fast charging is not battery healthy.
I don't know where you live and rates you pay for power but I drive 10k miles per year and my power bills are only $20-40 higher from charging my two EVS.
it is worth it not to waste time charging at a public charger, charging the cars at home while I am sleeping is so much better.

In rapid DC charging, I think there are two separate issues at play:

[1] the (initial) rapid influx of charging current which can result in heating. Assuming the battery pack is properly designed, I presume there should be no "excess voltage hot spots" within the battery pack. Hence, thermal is probably the key factor.
[2] as one exceeds 80-85% SoC, the battery voltage will approach the level where anodic plating/erosion might occur. This, I think, is the dominant battery life degradation problem.

If the above interpretation is correct, it begs the question whether there are any major difference between DCFC and L2 home charge when it comes to battery degradation. The typical L2 charger dispenses 8-12kW. A DCFC can deliver up to 350kW. However, at 85-90% SoC, I'd expect the DCFC charge rate to be less than 10-15kW. I'd also assume that the >80-85% charging is equally damaging whether it is L2 or DCFC since it is the same electrochemical process.

So, as long as one charges only to 80% on either L2 or DCFC, is there a difference when it comes to battery life degradation? Is it heat? Is it the charge rate? Is it the non-uniformity of the cell distribution?

Someone far more knowledge in battery/electrochemistry than I should educate us.

 

[REHPortland]

Got it…I think. Sounds like keeping the charging (on any charging system) up to or below 80% SoC is the most important factor with battery degradation. And, as you point out, charging at high levels 250-350 never occurs in the wild. At least, I have never seen these levels. All of you folks are advocating home charging and I agree. In my circumstance, adding the charger at my condo will be a PITA…as long as my “home” EA systems are working as well as they have, I’ll keep charging while I shop for groceries…I’ll add somewhere in the 350 mile range and be happy for the week. Thanks for everyone’s input.

 

[kort6776]

Got it…I think. Sounds like keeping the charging (on any charging system) up to or below 80% SoC is the most important factor with battery degradation. And, as you point out, charging at high levels 250-350 never occurs in the wild. At least, I have never seen these levels. All of you folks are advocating home charging and I agree. In my circumstance, adding the charger at my condo will be a PITA…as long as my “home” EA systems are working as well as they have, I’ll keep charging while I shop for groceries…I’ll add somewhere in the 350 mile range and be happy for the week. Thanks for everyone’s input.

there is nothing bad about charging to 100% or letting the SOC get below 20% as long as you do not let the car remain at those levels for extended periods of time. if embarking on a road trip and you charge your car to 100% for a morning departure you should be fine and while on that road trip you let the SOC get as low as possible before the nanny kicks in that is fine as long as you charge the car before calling it quits for the day.
on my other EVs it's known as driving the bottom of the battery which resulted in faster chargers. doing this requires pre trip planning to know where your charge stops are and also the location of alternatives in case the charger you planned on using is down.

 

[Lucken]

there is nothing bad about charging to 100% or letting the SOC get below 20% as long as you do not let the car remain at those levels for extended periods of time. if embarking on a road trip and you charge your car to 100% for a morning departure you should be fine and while on that road trip you let the SOC get as low as possible before the nanny kicks in that is fine as long as you charge the car before calling it quits for the day.
on my other EVs it's known as driving the bottom of the battery which resulted in faster chargers. doing this requires pre trip planning to know where your charge stops are and also the location of alternatives in case the charger you planned on using is down.

The caveat being that you should always have enough battery reserve to make it to a second choice charger in the event the first one is down.

 

[REHPortland]

10 4…another question, since you guys are so good at responding with great comments and information. Question: I leave my car in my parking garage for five months in the winter. It was charged Jan 2, to about 80%.. The car has been idle since then. I check the milage frequently and it is shows about 69% remaining today. So there has been some loss of of SOC…(much less than last season, when about 2-3 miles per day was lost. Seems like the OTAs have helped in this regard). Is it OK for Luci to sit idle for 5 months? The car is in a safe, secure and a mild temperature environment. Any data/info on this condition? Bad for the batteries? (Car was delivered Sept ’22 and has about 9100 miles today). Thanks.

 

[Shane_SLC]

10 4…another question, since you guys are so good at responding with great comments and information. Question: I leave my car in my parking garage for five months in the winter. It was charged Jan 2, to about 80%.. The car has been idle since then. I check the milage frequently and it is shows about 69% remaining today. So there has been some loss of of SOC…(much less than last season, when about 2-3 miles per day was lost. Seems like the OTAs have helped in this regard). Is it OK for Luci to sit idle for 5 months? The car is in a safe, secure and a mild temperature environment. Any data/info on this condition? Bad for the batteries? (Car was delivered Sept ’22 and has about 9100 miles today). Thanks.

I've typically heard for long term storage it's best to be between 30-50%, but I think this is typically plugged into at least a 110V outlet. This way you can still charge the battery enough from dipping down too low. I'd maybe worry about flat spots on tires with a car this heavy, but other than that as long as it's not sitting with very low SoC for extended periods it should be fine.

 

[DeaneG]

...So there has been some loss of of SOC…(much less than last season, when about 2-3 miles per day was lost. Seems like the OTAs have helped in this regard). Is it OK for Luci to sit idle for 5 months?...

If you can avoid checking the car's remaining charge frequently, you won't be waking it up and depleting the battery. Many report around 1% SOC loss every four days. Five months might mean 40% or more charge loss. I'd charge to 80% before parking it, and maybe have a friend charge it if it drops below 30% during that time.

 

[BS8899]

10 4…another question, since you guys are so good at responding with great comments and information. Question: I leave my car in my parking garage for five months in the winter. It was charged Jan 2, to about 80%.. The car has been idle since then. I check the milage frequently and it is shows about 69% remaining today. So there has been some loss of of SOC…(much less than last season, when about 2-3 miles per day was lost. Seems like the OTAs have helped in this regard). Is it OK for Luci to sit idle for 5 months? The car is in a safe, secure and a mild temperature environment. Any data/info on this condition? Bad for the batteries? (Car was delivered Sept ’22 and has about 9100 miles today). Thanks.

I left my AGT in my garage for 3-4 months in the Arizona summer, and plugged it into my L2 charger, so it was maintained @ 80% SoC. I did not encounter any problems. The only issue I encountered was my tires lost ~5psi each.

 

[APSenec]

10 4…another question, since you guys are so good at responding with great comments and information. Question: I leave my car in my parking garage for five months in the winter. It was charged Jan 2, to about 80%.. The car has been idle since then. I check the milage frequently and it is shows about 69% remaining today. So there has been some loss of of SOC…(much less than last season, when about 2-3 miles per day was lost. Seems like the OTAs have helped in this regard). Is it OK for Luci to sit idle for 5 months? The car is in a safe, secure and a mild temperature environment. Any data/info on this condition? Bad for the batteries? (Car was delivered Sept ’22 and has about 9100 miles today). Thanks.

Leave the car at 30% and in a cold environment. That is what Dr. Jeff Dahn at Dalhousie University has been recommending from LIB studies. This leaves the battery in a lower electro-chemical and thermal reactive state.

Here's a presentation he made.

 

[BS8899]

Well, maybe the Mill Valley chargers are simply defective. I've talked to several (~10) EV owners who routinely charge at that station. Vehicles involved range from Lucid to Porsche, to VW-ID4, Polestar, BMWs, etc.. No one gets above 75-80kW on a consistent basis, even with a low starting SoC (say, less than 20%).

Went to the Mill Valley CA EA charging station on Monday and found that it was being demolished. Perhaps EA didn't like the complaints? :-(


Realistically, most EVs don't benefit from greater than 150kW charging. Even those EVs that could take 300+kW (e.g., Lucids) only benefit from 300+kW charging " for a few minutes" when it is @ a low SoC and preconditioned.

It would be much better have 2X the number of chargers per station @150kW than few 350kW Hyper-Chargers. More 150-175kW chargers means more accessibility and low queue time and perhaps dedicated power provisioning (vs "balanced" shared provisioning between two 350kW chargers).

 

[Cosmo Cruz]

I really don't notice much of a difference in charging time using the EA 350 over the 150. Pretty reliably get 160+ kW initial from the 150 charger, more from the 350 initially (highest I've seen is 322kW @ 10% SOC) but the curve meets the 150 charge curve pretty quickly, so to get 80% it's just a few minutes difference between the two. I'm thinking the pull-out might be closer to 70% ... I love it when I plug-in after someone is charging then leave after 10 minutes. I can see them look up from their phones as if: "WTF?"

"oh, I'm ok. I only needed 200 miles." (I'm become an EV snob)

When I was young I never filled the gas tank. It was always: " uh ... give me $3 on pump 2 ".

Since then I've been filling the tank, or "charging to 80" as an adult...but wondering why? ... I can just poach an EA charger for a few minutes when they present themselves. I don 't need to fill-up every time ... It's like, "...oh...someone left 20 gallons of gasoline on the side of the highway... guess I'll pick it up." I still have 19 months of free charging at EA.

ICE cars are the horses of the modern era. "Oh look, a bale of hay, on the side of the road!" Try to imagine row upon row of functioning chargers under a lit canopy, with a rest room and coffee, and at the far end of a Wallmart parking lot : two lonely gasoline pumps ...out in the weather, unlit.

Imagine if you will, getting on the interstate and linking to the surrounding traffic so the possibility of collision is near zero. Maybe even real hands-free driving ? Interstate highways become train tracks. I'd love to look out the window more. I've started letting my wife drive. All this time she had the good seat. What was I thinking? Being the co-pilot is a cake job.

Lucid has changed the way I use a car. Did not expect this.

 

[momo3605]

I really don't notice much of a difference in charging time using the EA 350 over the 150. Pretty reliably get 160+ kW initial from the 150 charger, more from the 350 initially (highest I've seen is 322kW @ 10% SOC) but the curve meets the 150 charge curve pretty quickly, so to get 80% it's just a few minutes difference between the two. I'm thinking the pull-out might be closer to 70% ... I love it when I plug-in after someone is charging then leave after 10 minutes. I can see them look up from their phones as if: "WTF?"

"oh, I'm ok. I only needed 200 miles." (I'm become an EV snob)

When I was young I never filled the gas tank. It was always: " uh ... give me $3 on pump 2 ".

Since then I've been filling the tank, or "charging to 80" as an adult...but wondering why? ... I can just poach an EA charger for a few minutes when they present themselves. I don 't need to fill-up every time ... It's like, "...oh...someone left 20 gallons of gasoline on the side of the highway... guess I'll pick it up." I still have 19 months of free charging at EA.

ICE cars are the horses of the modern era. "Oh look, a bale of hay, on the side of the road!" Try to imagine row upon row of functioning chargers under a lit canopy, with a rest room and coffee, and at the far end of a Wallmart parking lot : two lonely gasoline pumps ...out in the weather, unlit.

Imagine if you will, getting on the interstate and linking to the surrounding traffic so the possibility of collision is near zero. Maybe even real hands-free driving ? Interstate highways become train tracks. I'd love to look out the window more. I've started letting my wife drive. All this time she had the good seat. What was I thinking? Being the co-pilot is a cake job.

Lucid has changed the way I use a car. Did not expect this.

I’ve been doing this too recently. 35 minutes to 80% (in a Touring) is a bit long to just hang out doing nothing. I just charge to 50 or 60% in about 15 minutes and then move on.

 

[BS8899]

Went to the Mill Valley CA EA charging station on Monday and found that it was being demolished. Perhaps EA didn't like the complaints? :-(


Realistically, most EVs don't benefit from greater than 150kW charging. Even those EVs that could take 300+kW (e.g., Lucids) only benefit from 300+kW charging " for a few minutes" when it is @ a low SoC and preconditioned.

It would be much better have 2X the number of chargers per station @150kW than few 350kW Hyper-Chargers. More 150-175kW chargers means more accessibility and low queue time and perhaps dedicated power provisioning (vs "balanced" shared provisioning between two 350kW chargers).

The question of charging speed and range anxiety depends a lot on the kind of car you drive and where you are driving. At the risk of broad-stroking,

Only a handful of cars (Lucid, Telsa long-range, etc.) have EPA rated range of 400+ miles and can charge @ greater than 250kW. In reality, the ACTUAL mileage and charge rates are significantly lower than these #s (400-mile range/250kW charge). According to the latest statistics, ~1 million EVs were sold in the US in 2023. More than 98% of these EVs have EPA range of fewer than 300 miles and most have an actual realizable range of fewer than 200 miles (i.e., getting down to 10-15% SoC thus creating range anxiety). Also, as EVs reach a broader market, not all EV owners live in homes that have at-home L2 charging. Many apartment/condo dwellers do not have overnight charging and they make up a significant part of the queues at the charging stations. When I am queuing at the EA Charging stations, I talk to the people waiting in the queue about their charging experience. Yes, some drive Porsches, BMWs, Mercedes, and rarely a Lucid. A good number of them live in apartments and condos. Some are Uber drivers. Most of the cars in line are VW ID4s, Ioniqs, Polestars, Chevy Bolts, etc..

My point is, most of the EVs (98%) waiting in the queue don't benefit from chargers over 150kW. Yet, the queue is part of our on-the-road charging experience and "real charging time".

I drive mostly the I-10 and I-5 routes between Phoenix and the Bay Area. California is blessed with a good number of charging stations along these major routes. The "anxiety" is not that I can't get to the next charging station before I run out of charge. Moreover, it is about broken chargers, slow charging (throttling), and queue time. I don't "wait" for the 350kW charger to open up. I will take the 150kW charger any day if it is open.

I strongly believe the "common good" is better served with MORE 150kW chargers than fewer 350kW chargers that throttle.

The charging landscape is changing with Tesla opening its chargers to others. Most of the Tesla charging stations have 100Kw-200kW chargers, but many of them. As the EV industry evolves, Tesla is transforming itself into an EV "Gas-station", where the money is! Great strategy!

 

[DeaneG]

For a long time, few EVs benefitted from more than a 50kW charging station. Now the same could be said of a 150kW station. In five years with battery advances, likely 350kW.

 

[BS8899]

For a long time, few EVs benefitted from more than a 50kW charging station. Now the same could be said of a 150kW station. In five years with battery advances, likely 350kW.

Yes, charging will advance. But I don't think it will be that fast. Limitations such as self heating, cost of material, etc. will limit the evolution. Yes, there will be "a few cars" that could benefit from the leading-edge technologies. But they are not the "center-of-the economic-gravity". Today, the numbers of EVs sold that could benefit from 350kW charging is (significantly) less than 2%.

Also, the charging stations will be renewed frequently, perhaps every 3-5 years. There is planet of opportunity to replace them with higher power charger when the time comes. Limited deployment of high-end chargers is a good publicity thing but has little economic return.

My argument is not about slowing down technical progress. History shows that technical progress must reconcile with economics to be successful. Witness the Concord. 50 years later, essentially all of our air travel is still subsonic.