Optimal External Temp for Charging??

SaratogaLefty

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Right now it is 107 here and I know it is way to hot to even attempt to charge the car at my local EA station. I'm just wondering if there is an optimal external temperature for fast charging?
 
I recall reading somewhere that the battery likes to be at 93 F.
Apparently, for current generation of EV batteries, their optimal temp is close to human body’s temp and they don’t function well outside of our temp comfort zone.
 
It's 113 here in Vegas today, and the EA chargers are performing abysmally - 3-20kW. I gave up.
The entire charging system, including the car's and the charger, need thermal control. If your car is at a good temperature but the charger just finished a blistering charging session, its components including the cable will be hot and charging performance limited. If the external temperatures are excessively hot, such as many locations in southern Nevada and Arizona, then the charging infrastructure will have challenges maintaining temperatures within operational ranges. Your car can precondition when you tell it to, but the charging infrastructure can't "pre" condition, it dynamically reacts to maintain range. With that in mind, you can try to charge early in the day and/or at a charger that has not been very recently used, but that of course may not always be possible.
 
The entire charging system, including the car's and the charger, need thermal control. If your car is at a good temperature but the charger just finished a blistering charging session, its components including the cable will be hot and charging performance limited. If the external temperatures are excessively hot, such as many locations in southern Nevada and Arizona, then the charging infrastructure will have challenges maintaining temperatures within operational ranges. Your car can precondition when you tell it to, but the charging infrastructure can't "pre" condition, it dynamically reacts to maintain range. With that in mind, you can try to charge early in the day and/or at a charger that has not been very recently used, but that of course may not always be possible.
Yes, went out early this morning when the temp was only 101! Got 147kW at 19%SOC then tapering to 40kW at 77% before I disconnected. In about 40 minutes.
 
BTW, the car fans continued to run after I parked my car - lost 2% charge doing that. I'm going to leave the garage door open and run my evaporative (swamp) cooler from now on during the summer months.
 
My car as been sitting outside at the service shop in Englewood, CO, in 100+ heat for over a week. Has lost 2% charge so far.
 
Trying to beat the heat by charging at home. Guess what? Autel charger ratcheting down to 4.8kW - half of the maximum where it started. Fans on the Lucid are at a dull roar. Leaving my garage door open to help ventilate. It's 7pm and still at 109 degrees. On the plus side, Lucid technology is helping preserve the battery with a nice conservative charging algorithm.
 
Trying to beat the heat by charging at home. Guess what? Autel charger ratcheting down to 4.8kW - half of the maximum where it started. Fans on the Lucid are at a dull roar. Leaving my garage door open to help ventilate. It's 7pm and still at 109 degrees. On the plus side, Lucid technology is helping preserve the battery with a nice conservative charging algorithm.
I set my car to charge at 4AM, I have a garage exhaust fan that starts running at midnight to cool off my garage. That combination usually keeps it in the low 90 degree range.
 
Trying to beat the heat by charging at home. Guess what? Autel charger ratcheting down to 4.8kW - half of the maximum where it started. Fans on the Lucid are at a dull roar. Leaving my garage door open to help ventilate. It's 7pm and still at 109 degrees. On the plus side, Lucid technology is helping preserve the battery with a nice conservative charging algorithm.
I would speculate that you may find the BMS spins the fans less, wasting part of the energy spent on charging, if you lower the max charge target on hot days to say 50-70%, and thus have to charge more frequently. I've noticed the fans kick into high speed mode when DC charging as the battery's charge level hits around 60% (probably depends on ambient air temperature, humidity and other factors, so your experience will likely vary quite a bit). If you're doing mostly local trips, a lower max charge may help you in terms of total time and energy. I would rather do some of my own measurements than speculate, but my situation doesn't allow for that at the moment.
 
In town, I’m still taking advantage of the 3-year freebie but I tend to disconnect when the charge rate plummets. Yeah, typically it’s around 70% the last month or so. I’ll keep notes on what happens when the weather cools.
 
At a time when EV sales growth is slowing, the industry is taking another hit. Although the recent reports center on Tesla, some of the issues are inherent to battery technology.


I mean, it's sort of ironic that these cold spells that are giving EVs trouble are caused by the fossil fuels we keep burning with our ICE cars.
 
I mean, it's sort of ironic that these cold spells that are giving EVs trouble are caused by the fossil fuels we keep burning with our ICE cars.
Let's be fair, we've had these cold spells long before we ever walked the planet. Our former ice ages are proof of that. I don't think I'd be comfortable blaming our current cold snap on fossil fuels.
 
At a time when EV sales growth is slowing, the industry is taking another hit. Although the recent reports center on Tesla, some of the issues are inherent to battery technology...
Current battery technology anyway.
 
Let's be fair, we've had these cold spells long before we ever walked the planet. Our former ice ages are proof of that. I don't think I'd be comfortable blaming our current cold snap on fossil fuels.
I won't argue the evidence of a weakening Jet Stream and its causes. That's not the purpose of a Lucid forum. So we'll take it back to the cars now.

It's really unfortunate what happened to that Supercharger station in Chicago. But it's not as simple as saying "Telsa screwed up" or that those drivers were dumb to let their cars drain that low before charging.

We need to come up with better home charging options, so that far fewer drivers depend on public charging. We also need to educate owners about features like Sentry Mode that drain your battery significantly more than most people think. My understanding is a lot of these folks got stranded because they parked their cars at the airport for an extended period, and understandably left Sentry Mode on for their peace of mind. Unfortunately, that left a lot of them with almost empty batteries when they got back.

I almost learned this lesson the hard way with my Model 3 when I went to Hawaii for a week. Fortunately, I checked my app two days in and saw how much my battery was losing per day. And I was able to remotely turn Sentry off.

I wonder if Tesla (and Lucid for that matter, if they ever decide to ship a Sentry Mode type feature) could send out a notification in situations like these. "Hey, we noticed your battery is draining 15% a day, and it's now below 40%. Do you want to turn off Sentry Mode?

Not that you want to leave your car unprotected. But compared to coming home to a dead battery in sub-zero temps, I'd like to be alerted to the option.
 
Imagine if airport long-term parking had chargers (or even just outlets) everywhere. They could charge ridiculous rates per kWh, like they already do for the parking itself, and people would absolutely pay for it. I'm sure it wouldn't be an easy project, but I think that's what the future looks like.
 
I also wonder if those at the Chicago charger gave it enough time to begin charging. Didn’t Out Of Spec find it took as much as 45 minutes for the battery heating to be sufficient enough to start charging in that kind of cold? I suppose some might have assumed the charger was broken and for all I know it was. Did Tesla ever acknowledge the chargers were all broken?
 
Imagine if airport long-term parking had chargers (or even just outlets) everywhere. They could charge ridiculous rates per kWh, like they already do for the parking itself, and people would absolutely pay for it. I'm sure it wouldn't be an easy project, but I think that's what the future looks like.
We have about 32 spaces at Denver International. They are free. And you can leave your car there as long as you like. So the chances of getting one are miniscule.

What we need is 300 spaces, not 32. But it's a start.

And yes, I wouldn't mind paying a premium on daily parking for one of those spaces.
 
I won't argue the evidence of a weakening Jet Stream and its causes. That's not the purpose of a Lucid forum. So we'll take it back to the cars now.

It's really unfortunate what happened to that Supercharger station in Chicago. But it's not as simple as saying "Telsa screwed up" or that those drivers were dumb to let their cars drain that low before charging.

We need to come up with better home charging options, so that far fewer drivers depend on public charging. We also need to educate owners about features like Sentry Mode that drain your battery significantly more than most people think. My understanding is a lot of these folks got stranded because they parked their cars at the airport for an extended period, and understandably left Sentry Mode on for their peace of mind. Unfortunately, that left a lot of them with almost empty batteries when they got back.

I almost learned this lesson the hard way with my Model 3 when I went to Hawaii for a week. Fortunately, I checked my app two days in and saw how much my battery was losing per day. And I was able to remotely turn Sentry off.

I wonder if Tesla (and Lucid for that matter, if they ever decide to ship a Sentry Mode type feature) could send out a notification in situations like these. "Hey, we noticed your battery is draining 15% a day, and it's now below 40%. Do you want to turn off Sentry Mode?

Not that you want to leave your car unprotected. But compared to coming home to a dead battery in sub-zero temps, I'd like to be alerted to the option.
The other problem is ride sharing people with EV's. They start their day with a charge (when the battery is cold) and don't precondition long enough. This takes a lot of time to charge the vehicle as a result. I blame lack of education
 
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