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This implies that it would take 133 kWh to fill the usable portion of the battery. There will, of course, be some charging losses, but unless Lucid has abnormally high charging losses, it does suggest that 118 kWh is the user-accessible capacity of the pack, not its total capacity.
 

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That is my reading as well.
Since I put up that post Tom Moloughney of "InsideEVs" has written that Lucid told him that the 118-kWh pack has no buffers, meaning the entire capacity of the pack is accessible to users.

It's not clear whether the Samsung cells used in the Dream are more resistant to damage from full charging and discharging, or whether Lucid is putting an additional burden on owners to protect the battery pack in order to maximize the range claims.
 

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Since I put up that post Tom Moloughney of "InsideEVs" has written that Lucid told him that the 118-kWh pack has no buffers, meaning the entire capacity of the pack is accessible to users.

It's not clear whether the Samsung cells used in the Dream are more resistant to damage from full charging and discharging, or whether Lucid is putting an additional burden on owners to protect the battery pack in order to maximize the range claims.
Maybe @Hydbob can answer but it seems like it's always on 80%. Maybe it defaults and you have to change it on purpose during a charge. Could there also be other things at play? Knowing you have the range you don't habitually charge it every day? We don't normally fill up our tanks with gas daily to keep it on "F."

My daily use is only 44 miles...
 

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Knowing you have the range you don't habitually charge it every day? We don't normally fill up our tanks with gas daily to keep it on "F."
Just as with our Tesla, Lucid recommends keeping the car plugged in whenever possible when parked. It's not about keeping the battery topped off. The reason is that if the ambient temperature moves outside of the optimal range, the car will activate battery heating or cooling to keep the batteries property conditioned, and it's better to do that off line power than battery power.

Even with insulated garage doors and two heat pump water heaters in the garage (which lower temperature and humidity of surrounding air), our Tesla's cooling system sometimes comes on while the car is parked.

As with our Tesla, we plan to keep the Lucid's charge limit set to 80% unless we raise it just before starting a long trip . . . and even then we usually only raise it to 90%, as I'm not sure the size of the buffer, if any, the Tesla has at the upper end.
 

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Discussion Starter · #10 ·
I have mine set to 80%. You can change it, but it won't let you lower it unless you are below that level, kind of weird. For example, it was at 98%, I wasn't able to set it down to 80 until after I got it down to 79%. You can always set it higher.

Yea, the ideal would be to keep it plugged in, however, with the drain and not being able to schedule right now, I can't keep it plugged in otherwise it would drain during the day wasting the charge to only replenish it at night.
 

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Yea, the ideal would be to keep it plugged in, however, with the drain and not being able to schedule right now, I can't keep it plugged in otherwise it would drain during the day wasting the charge to only replenish it at night.
I'm a bit confused. If the car has phantom drain, why would that militate against plugging it in? The drain, which you're going to get plugged in or not, would just be replenished by the line connection. Is it about peak/off-peak electricity rates?
 

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I guess I'm not following the tech in Tesla and maybe Lucid. If these cars are "connected" why can't they alert you if they have reached a critically low SoC? I get the need for cooling and maybe warming. If a car can remember to raise itself to go up your driveway it should be able to tell the outside temp via weather and manage appropriately. To me it should say when you park it, whether it can make it to the next day.

As I had mentioned my daily commute is 44 miles round trip. What's the point of collecting data if it's not being used to assist in daily use?
 

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I guess I'm perplexed why you want to avoid routinely plugging the car in when it's parked in your garage. It doesn't hurt the car; quite the opposite, as they are designed to be kept plugged in for extended periods to power battery conditioning when needed. The charging stops at the limit you set the charge, so no current is going through the cable unless the battery charge level drops. And, should you need the car unexpectedly, you don't have to worry about its not being charged to the limit you set.

I have the charger cradle on the wall right by the charge port for our Tesla, which I pass by, anyway, getting into and out of the car. (Fortuitously, when I installed two charging circuits in the garage when I built the house, I put them in locations that would accommodate a front or a rear charger port, as I didn't know what future EVs we would have. So one is ideally located for the Tesla's rear charging port and the other for Lucid's front charging port.) Taking literally a few seconds to plug and unplug the car is a habit I formed six years ago and never think twice about. I also never have to worry about a spur-of-the-moment change of plans that means taking the car out for a longer jaunt than was planned, as it is always charged up to limit when I'm ready to go.
 

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I totally agree with you, however I thought we were discussing battery degradation. At my age being sandwiched between baby boomers and Gen X. I've witnessed transition from NiCad to Li-ion, volatile to non-volatile memory. So to me we need to transition to better battery and charging management. I think this should occur with software and connectivity. That's all.

Lucid has released car without ability to charge on schedule. I may never use self driving, but let's see which is updated first. I would want car to only charge if it drops to a low point not maintain 80%. Which is better for battery? Everyone's situation is different, I guess in Florida one needs to be ready to flee the state in a moment's notice.
 

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If I'm doing calculation correctly, I'd need 20kWh to get to Lafayette where DC fast charger is located to get to Chicago in an emergency. That's 16% SoC? I'd like to set software to charge at 20% to charge up to 80%.

Still waiting on house back up which would change my plan.
 

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Discussion Starter · #16 ·
Yep. If we all had electricity rates like you have in Florida it would it wouldn't be a problem. But there is also the factor that you are just draining the battery for no reason, seems like a waste of electricity
 

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Yep. If we all had electricity rates like you have in Florida it would it wouldn't be a problem. But there is also the factor that you are just draining the battery for no reason, seems like a waste of electricity
I understand why not being able to schedule charging for off-peak rates is a problem that I can't imagine Lucid won't soon address. I don't, however, understand what you mean by draining the battery for no reason. Keeping the car plugged in should not cause a battery drain. In fact, it should prevent a battery drain when the battery heating or cooling is turned on to keep the battery within optimal temperature range, as the heating or cooling will run off the power line.
 

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I would want car to only charge if it drops to a low point not maintain 80%. Which is better for battery? Everyone's situation is different, I guess in Florida one needs to be ready to flee the state in a moment's notice.
What I've found from technical articles on the internet is that it's best to keep EVs plugged in when not in use, just as most manufacturers recommend. Battery degradation comes from dendrite formation, and the two biggest contributors to dendrite formation are overcharging and fast charging. Setting the battery charge limit at 80% as Lucid recommends for daily use addresses the overcharging risk to the battery. Keeping the car plugged in means that the car will be kept up to the 80% limit using a trickle charge, which is the "kindest" charge you can give a Li-Ion battery. Waiting for the battery to run down to 20% before recharging the car means that more of the charging is done at faster rates, which increases dendrite formation. Remember that the charge curve of every EV is designed to charge faster the lower the starting point from which you charge. Recharging even after your 44-mile commute means more of the battery recharging falls within the trickle charge. It also means that your battery is not drawn down when the heating or cooling system activates while the car is parked, as those systems will run off of your power line instead of the power, thus reducing the amount of recharging to which the battery is subjected.

Other than avoiding the peak electricity rates some power grids charge, there is no advantage to letting the battery charge routinely drop to 20% before recharging, while there is considerable advantage to keeping the car plugged in at an 80% limit when not in use.
 

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Discussion Starter · #19 ·
In my home charging test, when I plugged the car in to charge, it was 3pm. I had scheduled my Chargepoint to start charging at 10pm since that's when my rates were lowest. In the 7 hours the car was plugged in, it had lost 3% of it's SOC because it had the fans running expecting a charge to start just due to the plug being plugged in. This is what I'm referencing in terms of "wasted energy" because it definitely does not lose 3% SOC just sitting there when it's locked.
 

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In my home charging test, when I plugged the car in to charge, it was 3pm. I had scheduled my Chargepoint to start charging at 10pm since that's when my rates were lowest. In the 7 hours the car was plugged in, it had lost 3% of it's SOC because it had the fans running expecting a charge to start just due to the plug being plugged in. This is what I'm referencing in terms of "wasted energy" because it definitely does not lose 3% SOC just sitting there when it's locked.
Wow. Bizarre. Seems that a major software fix is due.

P.S. I wrote the above answer on the fly without digesting your post as well as I should. Looking at it again, I am still confused.

If the car was charging while plugged in -- and thus using power from the grid -- how was the SOC down by 3%? The charger should have topped off the battery to your preset limit and provided the power to run the fans. If it was the battery running the fans, you should not have been using power from the grid.

I'm not trying to be cantankerous here. I'm just trying to figure out what's going on here and whether I'm going to have a similar issue keeping my car plugged in when I get it. With both our old and new Teslas parked and plugged into the garage chargers, the fans have come on periodically while the car is parked because the battery pack temperature has risen beyond optimal. But they draw the power off the grid to run the fans, they only run for a short while, and the SOC does not drop.

Were your cooling fans running constantly for the entire 7 hours? What does Lucid have to say about the drop in SOC while parked?

The Lucid Owner's Manual specifically recommends keeping the car plugged in during extended periods of non-use. I can't believe they would recommend that if it means the cooling fans run nonstop the entire time. There has to be something wrong either with your car or with the charging software for all the cars.
 
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