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Hello all, I am quite new to this car and had it for about a week.
One thing that bugs me out is the regenerative brakes.

I usually lightly brake until I see the needle swipe to the CHARGE section.
However, is that dragging brakes as well?

When do you know when the real brakes kick in?
Or am I missing something here?

Dragging brakes will warp the rotors so I am not used to doing it.

What do you all think?
 

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If you pay close attention the feel, you should be able to tell. Regen brakes feel like smooth, rapid de-acceleration (like strong coasting down in speed), while the friction brakes feel more like normal cars, where you can tell the car is stopping quickly. I'm not sure how to explain it any better.

But otherwise, what exactly do you mean by "dragging" brakes?
 

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I guess what FireB meant by "dragging" brakes, is that if he's using his disc braking for an extended period, he's scared that he may warp his rotors.

Four things FireB that may help until such time that you can notice the subtle difference in feeling between regenerative braking and actual brakes:

1. As long as your needle swipe doesn't go to the far end of Charge, you are not using your real brakes. Regenerative braking is taking care of the entire braking.
2. Contrary to your beliefs, you really don't warp your disk brakes by "dragging" or gently braking for longer period, compared to hard braking. What's better for a metal alloy? slow change of temperature or a quick change when you brake hard?
3. The stories of long running Prius vehicles never having to change their brakes isn't uncommon. By brakes, I mean the brake pads; discs, just forget it.
4. As a proof, you'll notice your front or rear rims are not full of brake dusts unlike your earlier vehicles. This is because, regenerative braking takes care of the most of your braking.

If you want to hold you brakes for a longer period, here's a tip: Avoid water puddles as much as you can when driving. That change of disc temperature from hot to sudden cooling, is a big contributor for disc warpage. Also if you can, avoid drive by car wash after a long drive, for the same reason. Hope this helps. Enjoy your new car. It's meant to last.
 

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Discussion Starter #4
If you pay close attention the feel, you should be able to tell. Regen brakes feel like smooth, rapid de-acceleration (like strong coasting down in speed), while the friction brakes feel more like normal cars, where you can tell the car is stopping quickly. I'm not sure how to explain it any better.

But otherwise, what exactly do you mean by "dragging" brakes?
Thanks for your reply.
Dragging brakes is basically lightly stepping on the brakes all the time causing the rotor temperature to rise.
I guess that was a myth as other member has directed me with better understanding of brakes below.
I just have to get use to the feel of the brakes!

I guess what FireB meant by "dragging" brakes, is that if he's using his disc braking for an extended period, he's scared that he may warp his rotors.

Four things FireB that may help until such time that you can notice the subtle difference in feeling between regenerative braking and actual brakes:

1. As long as your needle swipe doesn't go to the far end of Charge, you are not using your real brakes. Regenerative braking is taking care of the entire braking.
2. Contrary to your beliefs, you really don't warp your disk brakes by "dragging" or gently braking for longer period, compared to hard braking. What's better for a metal alloy? slow change of temperature or a quick change when you brake hard?
3. The stories of long running Prius vehicles never having to change their brakes isn't uncommon. By brakes, I mean the brake pads; discs, just forget it.
4. As a proof, you'll notice your front or rear rims are not full of brake dusts unlike your earlier vehicles. This is because, regenerative braking takes care of the most of your braking.

If you want to hold you brakes for a longer period, here's a tip: Avoid water puddles as much as you can when driving. That change of disc temperature from hot to sudden cooling, is a big contributor for disc warpage. Also if you can, avoid drive by car wash after a long drive, for the same reason. Hope this helps. Enjoy your new car. It's meant to last.
Wow, I was too worries about something that is not even an issue eh?! LOL
Thanks for the tips you given me, it's a great read.
It's just that Regenerative brakes are so strong that I felt it was using 50/50.
Now it's all clear! Thanks!
 

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This thread really got me thinking about how regenerative braking works, and I realized I didn't really know much about it. I had assumed that regenerative braking, was simply a term used when the motors were generating electricity to charge the batteries, and the drag that creates was slowing the car. Basically, when you're coasting without applying pressure to the brake pedal. This thread made me realize that (according to the gauge), the amount of recharging of the batteries, actually increases based on pedal pressure. So, I did a little research here (the Wiki article was over my head):

Greenlings: How do hybrids and electric vehicles blend regenerative and friction braking?

Based on the article I read, I think what really happens is that is that the car (which has "drive by wire" braking) decides how much braking is required, decides how much regenerative braking it can provide, and uses friction braking to provide the rest. So you shouldn't really be able to determine when regenerative braking stops, and when friction braking starts. Not only does it change based on the braking requirement, they are most often used together

I would like to know if anyone interprets the information I got from the article, differently than me. Responses and feedback would be welcomed!
 

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This thread really got me thinking about how regenerative braking works, and I realized I didn't really know much about it. I had assumed that regenerative braking, was simply a term used when the motors were generating electricity to charge the batteries, and the drag that creates was slowing the car. Basically, when you're coasting without applying pressure to the brake pedal. This thread made me realize that (according to the gauge), the amount of recharging of the batteries, actually increases based on pedal pressure. So, I did a little research here (the Wiki article was over my head):

Greenlings: How do hybrids and electric vehicles blend regenerative and friction braking?

Based on the article I read, I think what really happens is that is that the car (which has "drive by wire" braking) decides how much braking is required, decides how much regenerative braking it can provide, and uses friction braking to provide the rest. So you shouldn't really be able to determine when regenerative braking stops, and when friction braking starts. Not only does it change based on the braking requirement, they are most often used together

I would like to know if anyone interprets the information I got from the article, differently than me. Responses and feedback would be welcomed!
They do mention that each manufacturer has their own implementation, even though they also claim they are all mostly the same. I don't think Toyota uses both brakes at the same time in varying degrees. They have a small regen meter in their hybrids which is easily passed due to the fact that, as stated in the article, the battery has a limit as to how fast it can receive charging. Once you pass that, the friction brakes begin to cut in slowly to assist. I think this is how Toyota does it.

Based on my driving, I can tell when regen switches to friction, I can even hear the brakes switching as I pull to a stop and slowly let go of the brake pedal (or what I believe to be the brakes switching.)
 
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