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Discussion Starter #1
Does using the regular foot brake also send energy back to the battery? Or does this only happen when you use the paddles?

Thanks in advance if you can help.

I do have some other questions as well, but let's see how we get on with this one first.
 

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Yes, its a core feature of EV's.... unless its an MG using cruise control!

Regen is used for braking, up to the point where they have decided to switch to purely friction brakes. This will be a function of max charge rate of the battery, or current capacity of the inverter. Because you can't use regen at very low speed, friction brakes are mixed with regen as speed decreases, with purely friction below a certain speed, somewhere below 10mph. Doing an emergency type stop varies between cars. Some go max regen and friction, but making abs work properly when you have a motor also braking is hard so below a certain speed, it'll be friction only.

I think all modern cars can exceed 20kW regen capacity, which is equivalent to quite aggressive braking. This can lead to a situation where brakes discs end up corroding due to no wear. Something manufacturers are presumably trying to address. See the MG comment above!
 

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The foot brake does regen - check the energy meter in the display.
Personally I prefer regen-0 over regen-3. Regen-0 you can apply power, and glide with inertia. Be wary doing this though as many ICE-drivers tend to accelerate to the last minute, and press hard on the brakes. They will be very annoyed following you if you are driving an EV very economically.
 

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Discussion Starter #4
Thanks for that. So do I understand correctly that whatever regen position I use (0,1,2 or 3) will have zero or minimal impact on the energy efficiency assuming I maintain the same exact profile of speed and acceleration in each case.

The only reasons to use regen. are if you find it easier/nicer to drive, and in order to save wear and tear on the brake pads on the wheel. The amount of electricity used will be the same either way or very similar.

Is that right as far as you know?
 

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Yes. For eg. Zoe is a fully manual system, different to the Ionic, it does not have a separate adjustment for regen, you just use the accelerator. The more you lift the accel, the more regen, if you lift off fully you get what would be fairly strong engine braking type decel. It responds in much the same way as an oil burner, so is 'easy' to drive, nothing new to learn. You have to keep in mind the accelerator in an EV is actually a speed selector, and this can be taken to the extreme, see 'one pedal driving'.

To your second comment...….Regen can be used instead of, or as well as mechanical friction brakes, but on an EV, you always use regen to bleed off speed before friction brakes, because to do otherwise is simply daft. You cannot control which braking system is used...….

Hypothetically speaking..... You are doing 60mph on a downhill stretch, feathering the throttle maintains a constant speed for 0 energy use. You are travelling for free. You must stop half way down. Whether you start slowing very early, or very late, the car will regen, faster in the latter case.

The important point is, you cannot choose how to slow down!
 

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Discussion Starter #6 (Edited)
but on an EV, you always use regen to bleed off speed before friction brakes, because to do otherwise is simply daft.
I think I'm still slightly confused...bear with me...I'm new at this...this should clarify it...

do you mean

A - it would be daft as a user to press on the foot brake first without using the regen paddles, because this would be needless wear and tear on the brake pads. You should use regen paddles where possible and then only step on footbrake as needed

or

B- it would daft from a design standpoint to have an EV that used friction as first option to slow down. And that even if I press gently on the foot brake (assuming not at a very low speed) it will not use the friction brake pads at first, or at all, only if needed for heavier foot braking. And so in theory with light braking you could be pressing the foot brake and no friction is being applied in some cases, purely regen. And that regardless of how you do it (paddles or foot brake) most or all light braking will be regen (except at low speeds).

At first I thought you meant A but after seeing your last comment "you cannot chose how to slow down" and re reading and re thinking the whole thread, I think you mean B?

EDIT: Re read the thread again. I think what I said in A is a total misunderstanding and what I said in B is probably at least closer to the mark. I think I get it now. But hopefully confirm just for sure that B is right to take away the last bit of doubt, thank you.
 

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Discussion Starter #7 (Edited)
Because you can't use regen at very low speed, friction brakes are mixed with regen as speed decreases, with purely friction below a certain speed, somewhere below 10mph. Doing an emergency type stop varies between cars. Some go max regen and friction, but making abs work properly when you have a motor also braking is hard so below a certain speed, it'll be friction only.

I think all modern cars can exceed 20kW regen capacity, which is equivalent to quite aggressive braking. This can lead to a situation where brakes discs end up corroding due to no wear. Something manufacturers are presumably trying to address. See the MG comment above!
Now I think about it, this explains something. A few days ago I was sat with the car parked on my drive trying out various features/controls/options as I read through the manual and when I came to the regen part of the manual I drove the car around the garden (possibly at about 10mph) trying out the regen and it seemed quite odd to me that there seemed to be no distinguishable difference between even positions 0 and 3, it was like the regen just did nothing. I tried it out today at different speeds (30-45mph mostly) and the different between 0 and 3 is quite a lot. 3 is really like pressing on the brake.
 

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Yes B is largely correct. Except to say heavy deceleration may still be using only regen. Certainly with most EV's, significant regen is available, enough for quite heavy braking effect.
 

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Discussion Starter #9
Thank you for helping me out Scott as well as Johnny earlier. After I posted the above I tried driving around just outside the house for a couple of minutes and I found that when I put my foot down on the brake fairly firmly at 10km/h (about 6-7mph) that there was no regen effect displayed on the power meter. At 20km/h, there was 1-2 bars displayed on the power meter.
 

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2020 Hyundai Ioniq Electric (38.3 kWh) Premium SE in Iron Grey with Shale Grey Interior option
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Remember if you are fully charged (or close to 100%) that the regen function is limited as there is nowhere to put the energy being generated. It can catch people out if you are used to lifting off to slow and get no regen because the battery is full. Only happens in limited circumstances but something to be aware of in case you have to stamp on the friction brakes. HTH

Derek
 

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Discussion Starter #11
OK, that's good to know. I assume that as soon as you touch the accelerator, even if the position is in 2 or 3, the car is smart enough to take the slight touch on the accelerator as a sign to stop braking, and not fight itself - it isn't simultaneously trying to brake and accelerate. In other words you can leave the regen position in 2 or 3 even if you are accelerating without any energy efficiency loss or anything bad happening (you don't need to toggle it back to 1 or 0 every time you accelerate).

I'm a bit hazy on the details but if regen braking means the motor is running backward and accelerator makes it forward it can't do both at once.

Is that right?

Also, when I turn off the ignition with the position in 0 or 1 regen, when I come back and turn it on again, the regen position has defaulted to 2. This is annoying because I had to teach my wife the regen just now - I didn't want to teach it to her yet because I want her to get used to an electric car as being something normal. Is there any way to stop that? I want the position to either default to 1, 0, or just start in the same position it was in when the car is turned off. Any ideas?
 

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You can set the regen default at 1,2 or 3, but not 0. The motor is rotating at a fixed ratio to the wheels, what changes is, accelerate and you put power in, cruise - no power in nor out, brake - use the motor as a generator. It only goes backwards when the car is reversing.

You have about 80kW (or more for 38kW model) of acceleration and braking, follow the information screen on EV throughout the power use screen - top right.

Disc brakes are used only for the last 6mph, emergency braking and on bumpy roads, the brakes will jump to discs especially on regen 0, less likely to happen on regen 1+, so going down hills it is better to use the regen paddle rather than the brake pedal.

If you find the power screen, follow top right section through, then on regen 3 you will see how much power is used on different driving situations.
 

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You can't set the regen to default to 0. Have to pull the RH paddle every time you restart to get to Regen 0. Have a read of the other thread - will answer a lot of your questions. New MY2020 38kWh Queries & Observations

When is regen is 0, you can press the brake pedal quite hard and it still regenerating. @Ralkbirdy when you say "the brakes will jump to discs especially on regen 0", can you define that a little more? If slowing down gracefully, I can't see why the disc brakes would be used much, if ever?
 

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Discussion Starter #16

You need to go to the settings page for 3 driving modes and it should be there.
EV,
Drive mode settings
Normal
The choose level.

The energy screen is
EV,
Energy
Energy consumption.
Thanks. The screen you are showing in the jpeg, does that correspond to this one in the centre of the car where the radio controls are? This is a photo I just took of my car. What buttons should I press or what should I do starting from the below picture in order to find "EV" , the first thing I need to find to follow those instructions?

130250
 

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When is regen is 0, you can press the brake pedal quite hard and it still regenerating. @Ralkbirdy when you say "the brakes will jump to discs especially on regen 0", can you define that a little more? If slowing down gracefully, I can't see why the disc brakes would be used much, if ever?
If you are slowing down and the road is uneven, if the wheels start bouncing then the car may switch from regen to disc. Potholes will do it.
 

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What buttons should I press or what should I do starting from the below picture in order to find "EV" , the first thing I need to find to follow those instructions?
On my photo you have the home page with navigation map and EV icon, also under those buttons is a separate EV button at the bottom of the picture, this is mk1 28kW version.
 

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Discussion Starter #20
The physical EV button, to the right of the hazard sign....I don't have that.

I also have never seen an EV icon appear on the screen after going through the options on the screen. Where it has an EV icon with a green symbol of some kind (a leaf?) I have never seen that on the screen although I tried to get it.

As far as I know, there is no map or navigation. I have certainly never seen it after manually working my way through every menu and sub menu I can find. 1 year ago, when I tried to buy another Ioniq in Chile, the owner told me the car was without sat-nav and I think that was the same basic model - I think nearly all the ones on sale in Chile are this basic model.

Maybe none of the options exist, at least not on that screen, and that is why it's a smaller screen on my version. If the screen is mostly just for radio info it doesn't need to be as big.

But without this, I don't see how to set the regen to 1 by default, not to mention other things like:

I can't
--display the km/kWH of the last trip.
--display the current % charge if the car is not plugged it (it only displays in the dash area when charging and even then only if I open the door)
--select the charging amps/watts preferred for trickle charging
 
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