Regenerative braking

[Breezy]

New owner of Air Pure 2023 AWD since April 10, 2024. No regen braking at 90 percent or above. It comes back to life below 85 percent SOC

This makes sense…

 

[kort6776]

I just want to share my bad experience when I charged to 100% and the drove just 1 mile to my hotel. The parking lot was in the basement about 30 feet below the street level. There was a 1 foot hump from the road before descending into the parking lot. That hump is meant to prevent rain water from going into the basement. I crossed the hump and I was only going 10mph to make a 90 degree left about 100 feet away. I had almost no regen and I could not brake fast enough. I had $40k of damage (mostly the front sensors on the bumper, Lidar, bumper, air bags, steering, frunk and it took 3 months to get my car back. Good news is that the car was perfectly restored and after that I drove 11k flawless miles with some simple caution. Charge to 100% ONLY before a long distance trip and only when I know that till 95% I am on a flat road. At 95% the regen appears close to normal. For my local driving I usually charge only once a week 45% to 80% and it meets my needs. As others mentioned, Lucid does not use hydraulic brakes at 100% to simulate the same result as regen. I hope this tale of caution helps you and others prevent what happened to me.

when the car is at such a high SOC, the regen will not work well because there is no place for the recovered energy to go, the battery is already full.
the moral to the story is to be aware of this and drive accordingly

 

[blueice89]

Every now and then I can one of these scary slips I do agree some software update adds a little more roll maybe according to how pressed down accelerator is but I got no clue just my observations. Drive it smoothly is my advice don’t be in a hurry enjoy the ride

 

[kpbhat]

Regenerative braking seems to be quite variable. My car is getting a front sensor replaced, but prior to this…definitely a noticeable change. Similarly, I have a loaner…and the braking seems to vary with no rhyme or reason.

I don’t think regen braking has anything to do with sensors. In simple layman’s terms, It’s just the same drive motor changing into a dynamo to generate energy when you let go of the accelerator. Regen is prevented and motor decoupled from drive, only if the battery cannot take anymore power from motor to store. So this can happen when the battery is full /almost full or it’s too cold outside and battery has to be warmed up sufficiently to accept the power. Basically regen is prevented as safety measure and I think there is a warning that gets displayed.

 

[HariK]

when the car is at such a high SOC, the regen will not work well because there is no place for the recovered energy to go, the battery is already full.
the moral to the story is to be aware of this and drive accordingly

Exactly. That is why I shared it. As @Bobby pointed out, it is the way Lucid currently does while some other EVs use hydraulic braking to simulate the same level of one pedal driving at any SoC. That can change with a software update in future assuming the Lucid hydraulic braking can also be controlled by software.

 

[Rossb2k]

I don’t think regen braking has anything to do with sensors. In simple layman’s terms, It’s just the same drive motor changing into a dynamo to generate energy when you let go of the accelerator. Regen is prevented and motor decoupled from drive, only if the battery cannot take anymore power from motor to store. So this can happen when the battery is full /almost full or it’s too cold outside and battery has to be warmed up sufficiently to accept the power. Basically regen is prevented as safety measure and I think there is a warning that gets displayed.

As I've mentioned earlier in this thread - unless it was changed recently and I haven't noticed - there is currently no indictation if regen is limited or unavailable. Which is weird, considering Tesla and other competitors have a visual indicator for it and even flash a warning.

 

[kort6776]

Exactly. That is why I shared it. As @Bobby pointed out, it is the way Lucid currently does while some other EVs use hydraulic braking to simulate the same level of one pedal driving at any SoC. That can change with a software update in future assuming the Lucid hydraulic braking can also be controlled by software.

hydraulic? please enlighten me, which EVs use any sort of hydraulic braking to simulate regen braking

 

[kort6776]

As I've mentioned earlier in this thread - unless it was changed recently and I haven't noticed - there is currently no indictation if regen is limited or unavailable. Which is weird, considering Tesla and other competitors have a visual indicator for it and even flash a warning.

agreed that tesla will indicate that regen is limited and Lucid should do the same. I wonder what the code monkees have to say ?

 

[borski]

agreed that tesla will indicate that regen is limited and Lucid should do the same. I wonder what the code monkees have to say ?

I suspect this is something you’ll see relatively soon. Seems a useful fix.

 

[HariK]

hydraulic? please enlighten me, which EVs use any sort of hydraulic braking to simulate regen braking

I don't know first hand. See other postings here. I can test my wife's ioniq 5 at 100% and see what it does and report here what I find.

 

[kort6776]

I don't know first hand. See other postings here. I can test my wife's ioniq 5 at 100% and see what it does and report here what I find.

I think that you are confusing the hydraulic braking systems with regenerative braking.

Regenerative braking is a mechanism found on most hybrid and full-electric vehicles. It captures the kinetic energy from braking and converts it into the electrical power that charges the vehicle's high voltage battery. Regenerative braking also slows the car down, which assists the use of traditional brakes.

A hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing glycol ethers or diethylene glycol, to transfer pressure from the controlling mechanism to the braking mechanism.

 

[Pragmatic]

I have lost regeneration twice, both in roughly the same place.

When I go skiing I stay at a house near the base of the hill. Twice when leaving, temperatures in the mid 20s F, SOC around 50%, I lost regeneration approximately 6 - 8 miles after leaving to go home.

The drive is up ~10% grade for a gain of about 700 feet over ~ 1.5 miles, then down grades between 0% and 13% for a total loss of 2000 feet over ~6 miles. During maybe the fifth downward pitch I would lose all regeneration. I drive in swift with minimum regeneration to limit braking on slick surfaces.

I've taken it as a cold battery reaching the limit of what it can take. I never get above 50% SOC but I can't help feeling that after 4 or five regeneration from 45mph to 30 mph on 10% grades the software limits what goes into the cold battery.

Never a problem on the first set of grades. Once I lose it it comes right back and works normally on the next grade. Only reason I don't think its something I've done is it did it twice in almost the same spot under similar conditions.

 

[Steveinarizona]

I don't know first hand. See other postings here. I can test my wife's ioniq 5 at 100% and see what it does and report here what I find.

I believe they are not comparable. The Hyundai group EVs (Kia, Hyundai, Genesis) use a blended brake system where the first depression of the brake pedal invokes regen (unless one turns regen off entirely) while a firmer depression invokes the friction brake. To compare, one needs to use a company that doesn't use a blended brake system such as Tesla and Lucid where using the brake pedal immediately invokes the friction brake.

 

[segbrk]

I think that you are confusing the hydraulic braking systems with regenerative braking.

I think Hari is just talking about friction brakes automatically supplementing regen when necessary to make one pedal driving feel the same regardless of temperature or state of charge. Tesla has a setting for this and I believe some other manufacturers do it as well. It sure sounds like a great feature if implemented well.

 

[bill1745]

No. In fact, your brakes will last much longer, because you are barely using them.

Does make sense to do a form brake (in a safe place) every now and then to get any dust and rust off the rotors. But otherwise, I always advise folks to switch to hi regen and live the one-pedal life.

For what it's worth, I have standard regen and drive one-pedal all the time. My driving is almost 100 percent on city streets.

 

[bill1745]

I believe they are not comparable. The Hyundai group EVs (Kia, Hyundai, Genesis) use a blended brake system where the first depression of the brake pedal invokes regen (unless one turns regen off entirely) while a firmer depression invokes the friction brake. To compare, one needs to use a company that doesn't use a blended brake system such as Tesla and Lucid where using the brake pedal immediately invokes the friction brake.

That would explain why I had regen breaking at 100 percent change on my Genesis GV-60, while on my Lucid I do not.

 

[borski]

That would explain why I had regen breaking at 100 percent change on my Genesis GV-60, while on my Lucid I do not.

Yeah - you didn’t have regen braking. You had friction brakes that it pretended were regen so you didn’t get uncomfortable.

I agree it’d be a neat and useful feature for Lucid to add.

 

[Instinctive]

Yeah - you didn’t have regen braking. You had friction brakes that it pretended were regen so you didn’t get uncomfortable.

I agree it’d be a neat and useful feature for Lucid to add.

Yeah it really would. Possibly number one on my list at this point. It's the only feature I'm missing that actually feels like it creates danger. Others are just creature comforts to me.

 

[borski]

Yeah it really would. Possibly number one on my list at this point. It's the only feature I'm missing that actually feels like it creates danger. Others are just creature comforts to me.

The easier, and much more likely, feature to add is just a warning that regen is limited. I wouldn’t be surprised if we see that sooner.

 

[kpbhat]

Yeah it really would. Possibly number one on my list at this point. It's the only feature I'm missing that actually feels like it creates danger. Others are just creature comforts to me.

But then there has to be a sign somewhere on dashboard that indicates friction braking is on? Otherwise how driver will know if it’s regen or friction braking?