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Discussion Starter #1
So it’s embarrassing to have got to nearly a year’s ownership and only just realised I don’t really understand the regen side of the power gauge.

Sometimes the “available” blue sectors reach all the way down the left side of the gauge, and if I’m slowing fast from a high speed they all light up. But sometimes they only reach a handful of sectors down. I think I had vaguely assumed it was to do with speed, but it isn’t (I paid attention yesterday, at varying speeds).

It appears - and this is logical - to be to do with SOC. However, although I can understand that at 100% SOC there is little if any room for regen, I wasn’t up to full availability for quite some time - I noticed it at 73%, may have been earlier. There seems to be at least one intermediate stage between the minimum available and fully available.

Any insights? And is this another reason for trying to limit the normal SOC to between 20-80?
 

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The blue lights show the strength of the regen. You get less when you are at 100% SOC because it can't put any more energy back into the battery.
 

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It's the same as the way rapid charging speeds are reduced at higher states of charge. The limit is to protect the battery. I'm not certain how much power maximum regen can generate, but I assume it's in the 10s of kW.
 

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Any insights? And is this another reason for trying to limit the normal SOC to between 20-80?
In short, yes. I have a Leaf 24 - which behaves a bit differently (and is much quicker to get "down" from 100% to ~90% where decent regen is available), but sticking to ~80% where possible/sensible will work best.
 

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My Leaf 30 usually allows max regen once its down to around 89% soc ambient temperature does not seem to affect this but i have noticed my 40 limits regen for much lower into the soc,again down in the mid 70s it will not necessarily have all of the regen blocks showing.But it has been generally cold lately so not sure if a cooler battery is having an influence on it.
 

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Discussion Starter #6
Great, thanks all.
 

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I'm not certain how much power maximum regen can generate, but I assume it's in the 10s of kW.
You just have to select the Energy Usage display on the infotainment screen to see that the maximum regeneration power is 30kW (on a 40kWh LEAF). That's not as much as it could potentially be. If you watch Formula E you'll notice that those cars can produce just as much regen. power as the motor produces, i.e. maximum power output is 250kW and maximum regen. is also 250kW. However, 110kW of regen on a LEAF would be quite harsh slowing down!
 

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... not sure if a cooler battery is having an influence on it.
Yes, in cold weather there is less regen. available. That's to protect the battery, just as it would throttle back a rapid charge on a cold battery (30kW of regen is quite a high charge rate - around 2/3 of maximum rapid charge rate on a LEAF).
 

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Also worth knowing that to get the best economy, thay youl should avoid regen as much as possible (sounds counter Intuitive I know), but you just need to understand the losses behind regen and that coasting is highly more efficient than regen.

Basically if you're at 60mph and need to stop in 500 meters, instead of driving 300 more meters at 60mph and regen to a stop for the last 200, is far more economical to drive 100 more meters and coast in neutral to a stop for the next 400 meters.
 

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Discussion Starter #10
Just correcting myself now I’ve paid more attention - there isn’t any jump in the number of regen sectors showing, it‘s a steady progression. Seems (on my Leaf 40) to start at about 2-3 sectors when fully charged, and then to pick up roughly a sector per percent drop in available charge. Still haven’t quite spotted where the full regen becomes available, but it’s somewhere around 75%.

it does explain something I had previously noticed, that SoC seemed to drop more rapidly at the start of a long journey (when I would be fully charged) than later on, which just went to feed my range anxiety. Although I do try and avoid braking wherever possible, the inability to recover much of the power from it in regen was obviously part of the reason.
 
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Don't read into those figures too much. They're all just representations of whatever the software says.
The battery doesn't give a %, just a certain Ah. It's up to software to tell you how much Ah is each ‰
 
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