Max Regen Question (edited title..)

DanN427

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Did a bit of searching and couldn't find anything on this..

How much of a charge do you get while in Max Regen Mode? Could you get the battery up a decent amount if down in the single-digit levels? I know time driving and distances will effect this, just looking for a general idea.





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Crawldad

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i'm pretty sure brake regen happens when you are hitting the brakes... i think this will answer your question.
 

Jocko

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Regen braking has nothing to do with the brakes. In fact hitting the brakes would reduce the energy available for regen.

I don’t think it’s possible under most circumstances to actually get a net gain in battery charge because regen will always be recapturing a fraction of the energy you needed to get up to speed in the first place. Presumably if you were coasting down in elevation for miles on end it might happen. But of course the opposite would be true if you were going to later be returning the same way.
 

phobos512

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It is physically impossible to charge the battery up over a (I meant ROUND TRIP here) using regenerative braking. The motor would have to be more than 100% efficient operating in reverse, which it is not (100% would get you the same energy in as out; in reality electric motors are in the ~8x% efficiency range when driving the vehicle; the remainder is lost as heat).
 
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Dryver

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It is physically impossible to charge the battery up over a journey using regenerative braking. The motor would have to be more than 100% efficient operating in reverse, which it is not (100% would get you the same energy in as out; in reality electric motors are in the ~8x% efficiency range when driving the vehicle; the remainder is lost as heat).
When running in eSave mode, the battery can be recharged in about 2 hours at 55 mph (or something along those lines). Max regen while running in Hybrid or electric will give you extermely mild gains when slowing, but don't expect miracles. I've seen my percentage increase by one point when slowing, probably briefly after it had just reduced by one point, but unless you're headed downhill over a long stretch, it's not going to do much.
 

phobos512

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When running in eSave mode, the battery can be recharged in about 2 hours at 55 mph (or something along those lines). Max regen while running in Hybrid or electric will give you extermely mild gains when slowing, but don't expect miracles. I've seen my percentage increase by one point when slowing, probably briefly after it had just reduced by one point, but unless you're headed downhill over a long stretch, it's not going to do much.
I did specify over a journey, and I should've said "round trip" more specifically...Unless you're going one way, you're not making up the energy you used to power the vehicle by regen (if you're going one way only down a hill then yeah you could theoretically end up with more energy at the bottom than you left with but that's the only possible configuration that can happen in). E-save is a completely separate discussion.
 

ElHobbz

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I did specify over a journey, and I should've said "round trip" more specifically...Unless you're going one way, you're not making up the energy you used to power the vehicle by regen (if you're going one way only down a hill then yeah you could theoretically end up with more energy at the bottom than you left with but that's the only possible configuration that can happen in). E-save is a completely separate discussion.
Does that mean regen breaking captures enough energy to combat energy use from a/c, stereo, and other energy parasites (net positive)? (Sorry for dumb question I have a CS background not EE)
 

Arterius2

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I did specify over a journey, and I should've said "round trip" more specifically...Unless you're going one way, you're not making up the energy you used to power the vehicle by regen (if you're going one way only down a hill then yeah you could theoretically end up with more energy at the bottom than you left with but that's the only possible configuration that can happen in). E-save is a completely separate discussion.
Yes, but noone is asking about charging up the battery in electric mode.

The question simply was the charging rate when using max regen.

The generator will charge the battery over time in E-save mode.
 

Dryver

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Does that mean regen breaking captures enough energy to combat energy use from a/c, stereo, and other energy parasites (net positive)? (Sorry for dumb question I have a CS background not EE)
Here's my experience as I've been driving in eSave to break in the engine for the last several days. Once the battery level drops to 95%, it still uses battery when starting from a stop to get moving, and at times on a level road. It never drops below 95% while doing this, and doesn't need to have max regen on to do it either. From this, I am reasoning that it recaptures enough energy for parasitic drains as well as keeping charged, but I have not used AC yet.
 

michail

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Here's my experience as I've been driving in eSave to break in the engine for the last several days. Once the battery level drops to 95%, it still uses battery when starting from a stop to get moving, and at times on a level road. It never drops below 95% while doing this, and doesn't need to have max regen on to do it either. From this, I am reasoning that it recaptures enough energy for parasitic drains as well as keeping charged, but I have not used AC yet.
The battery may still be using the AC. Now I'm curious if that shows on the climate control usage.
 

rdmelton

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When running in eSave mode, the battery can be recharged in about 2 hours at 55 mph (or something along those lines). Max regen while running in Hybrid or electric will give you extermely mild gains when slowing, but don't expect miracles. I've seen my percentage increase by one point when slowing, probably briefly after it had just reduced by one point, but unless you're headed downhill over a long stretch, it's not going to do much.
I did a test of driving about 2 hours at 70 mph in e-save (battery charge) mode, and got about 25% battery charge (started at <1%). It was on an interstate in a moderately hilly area.
 

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