The best intentions to stave off battery degradation

[Leafnut]

So I had a round trip to Corpus Christi today from Austin--221 miles leg/442 round trip. The only EA chargers are in San Antonio--roughly 80 miles from my house.
I know the following:
1. Charging the battery to 100% should be avoided
2. DC Fast Charging should be used sparingly
3. Don't let the SOC go below 10%
The trip required a violation of at least one of the three aforementioned points. So I picked #1 and charged to 100%, hoping that best case scenario, I could make the round trip home if I hypermiled, or at least back to San Antonio, with over 10% SOC and would violate #2 by fast charging. Well, it was hotter than hell's kitchen again in Texas today (100°) and I think it killed my efficiency, despite my best efforts to moderate my speed. I ended up violating all three. I made in back through San Antonio with 8% SOC, fast charged to 45% and arrived home at 23%. I averaged 3.95mi/Kw.
Any advice on a better tragedy? What Is the order (worst degradation) of the three points? How much does hot weather affect efficiency?

 

[Leafnut]

Strategy, not tragedy. Although I suppose it did feel somewhat tragic

 

[Buffalo Bob]

I suggest that you avoid #1 and #3 like the plague and don't worry about #2. DC fast charging is not that big a deal, especially if you precondition your battery and avoid charging above 80% unless really necessary. I solely charge at EA, and my battery health is just great (97.2% on the API) after 18 months. I didn't map the route but it sounds like a quick charging stop in San Antonio on both the way there and back would have relieved a lot of stress.

 

[scal_air]

The trick with charging to 100% is to not leave it there. So I try to end the charging session within a few hours of starting the long trip.

 

[Bus Driver]

The trick with charging to 100% is to not leave it there. So I try to end the charging session within a few hours of starting the long trip.

Same here. I charge to 100% about once a week, averaging three or four times a month. I just make sure that I leave within a half hour of charging to 100%. By this method, I get to do my 280 mile roundtrip commute to work, and end up back in my garage with 30% to 31%.

I consciously violate number 1, so as to avoid violating number 2 and 3.

 

[Leftlane]

Not sure why you would worry about any of those 3 items - none will hurt your battery, and you have a long battery warranty anyway. Stressing about a simple trip like this takes every ounce of fun out of owning an EV. Charge to 100% when you need to, DC fast charge when you need to, and plug in when you can. There are literally hundreds of studies that show calendar aging happens no matter how you charge, and going to 100% or below 10%, or supercharging, does not hurt your battery nearly as much as you think.

You bought the longest range EV with super fast charging capabilities and unbelievable acceleration, and are kneecapping yourself on all fronts by effectively limiting yourself to 70% of the ideal range and worrying about DC charging, while driving like a grandma. I wouldn’t worry about any of this at all and would just enjoy the hell out of your car.

 

[jedwin]

make sure that I leave within a half hour of charging to 100%.

I’m sure this has been discussed before, but I’ve been curious about how long the “don’t let it suit at 100%“ guideline applies to. A half hour is surely hyper-cautious, but what’s a good rule of thumb? 6 hours, 24 hours?

What data is there on the effect of repeated occasional full days at a high SOC?

(I only need to push it to 100% at home for longer road trips, once or twice a month. But in the summer, I go back-and-forth between a house and town with my L2 charger and a camp at a pond where I’ll only have 110 charging – so I might want to top it off in town and leave it there for a day or two before I hit the road. I could also charge to 90 or 95 in town and trickle-charge it to 100 overnight at the pond before the trip if that’s better practice)

 

[hmp10]

Tom Moloughney of "State of Charge" recently interviewed Emad Dlala, Lucid's SVP of Powertrain. Dlala dropped something of a bombshell on Moloughney, He said that fleet data Lucid was collecting on Air battery packs showed that a mix of Level 2 and Level 3 charging was producing the best results in terms of battery pack degradation. This was shocking news to Moloughney and flies in the face of most conventional wisdom about avoiding DC fast charging as much as possible. Dlala said it appears that there is something about swapping between AC and DC charging that appears to keep the cells more robust and that, basically, you can DC fast charge a Lucid as much as you want without worry.

The discussion begins at 23:40 of this video:

 

[joec]

The thing about guidelines is that they are guidelines. They aren’t holy scripture.

Charge your car as needed and don’t think about it. These batteries are built to take a lot of punishment. All the crazy inconveniences people put themselves through to help save a tenth of a percentage of battery degradation are really not worth the headache.

The real guideline is simple: don’t be totally stupid with your battery. Don’t DC fast charge your car every day to 100% and drain it to 2%. Outside of that, there’s nothing to worry about.

 

[Steveinarizona]

The thing about guidelines is that they are guidelines. They aren’t holy scripture.

Charge your car as needed and don’t think about it. These batteries are built to take a lot of punishment. All the crazy inconveniences people put themselves through to help save a tenth of a percentage of battery degradation are really not worth the headache.

The real guideline is simple: don’t be totally stupid with your battery. Don’t DC fast charge your car every day to 100% and drain it to 2%. Outside of that, there’s nothing to worry about.

Yup. Your behavior might have cost you as much as one mile in your estimated total battery life of at least 100,000 miles. Shocking.

 

[MGRMLN]

How do we see our battery health data?

 

[illopp00]

I’m sure this has been discussed before, but I’ve been curious about how long the “don’t let it suit at 100%“ guideline applies to. A half hour is surely hyper-cautious, but what’s a good rule of thumb? 6 hours, 24 hours?

What data is there on the effect of repeated occasional full days at a high SOC?

(I only need to push it to 100% at home for longer road trips, once or twice a month. But in the summer, I go back-and-forth between a house and town with my L2 charger and a camp at a pond where I’ll only have 110 charging – so I might want to top it off in town and leave it there for a day or two before I hit the road. I could also charge to 90 or 95 in town and trickle-charge it to 100 overnight at the pond before the trip if that’s better practice)

It will never really stay at 100% due to phantom drain, but don't leave it plugged in trickle charging to 100%, and ideally not above 90 Deg F. I never use 100% percent because I lose regen. 100% is for max range and helping calibrate the BMS.

 

[illopp00]

How do we see our battery health data?

Log In - Unofficial Lucid API

Use your Lucid App/Portal Login. It's raw code output but search for 'health'.

 

[joec]

Log In - Unofficial Lucid API

Use your Lucid App/Portal Login. It's raw code output but search for 'health'.

Yes. And keep in mind that this number is the end of an equation that none of us fully understands. Lucid has never said what the “health” number means exactly. So take it with a grain of salt.

 

[Bdr100]

The biggest problem I see with this trip plan was the reliance on EA Charging, I assume because it is free. There are numerous non-EA CCS chargers available in Corpus as well as along the direct route between Austin and Corpus. Driving 80 miles out of your way to get to free EA station is “penny wise-pound foolish.”

 

[franks]

Have a materials science background and know batteries pretty well. I have seen nothing peer reviewed that shows enhanced degradation from charging EV batteries to 100% nor DC versus AC charging. It is correct that leaving a battery charging for a long time can cause slight loss of capacity. In any case, I personally don’t take any steps other than always charging to 100% and then disconnecting.

 

[petergottlieb]

I totally get that for some of us some battery health optimization is part of the fun, but as others have said, don’t lose sleep over it.

It seems like the more we learn the more confidence we can have that EV batteries are very robust under normal use for a very long time. My own SOP is to daily charge to between 60-80 percent, and charge on the freeway around 10 percent just because I want a little margin to limit my stress about charging. I only need to fast charge on very long distance trips, which means I need it less than once a month.

 

[borski]

The thing about guidelines is that they are guidelines. They aren’t holy scripture.

Charge your car as needed and don’t think about it. These batteries are built to take a lot of punishment. All the crazy inconveniences people put themselves through to help save a tenth of a percentage of battery degradation are really not worth the headache.

The real guideline is simple: don’t be totally stupid with your battery. Don’t DC fast charge your car every day to 100% and drain it to 2%. Outside of that, there’s nothing to worry about.

Amen.

 

[illopp00]

Yes. And keep in mind that this number is the end of an equation that none of us fully understands. Lucid has never said what the “health” number means exactly. So take it with a grain of salt.

I ran the code before and after a monster DC charging in 90 Deg F and managed to get it to go from 98.0 to 97.9.....