optimizing braking regen

#20116 Nowhere. It's written nowhere. I've seen my antique 2013 BEV's power gauge read 72kW under heavy braking down hill. If I then coast to a stop, the friction brakes are stone cold, proving that regen did ALL the braking.

HOWEVER, if for example you fully charge at the top of a hill then the battery can't absorb the full regen braking energy, unless the car has a large buffer specifically reserved for braking.

On other threads of this forum there have been a few ideas for it, including that buffer, &/or activating max A/C & heat simultaneously, biased very slightly to maintain cabin temperature. If needed, over-spec them both to absorb enough energy.

Aptera once again has the advantage here too: It's low weight requires less energy to decellerate.

@#20116 My hybrid and others can routinely only recover ~%30 via de-acceleration regen - someone on an Aptera vid (if I recall) mentioned it was because the current spike is too high - which makes sense as you can't force a chemical reaction beyond limits - and there can be resistive loss in wires for that much current too ... hence putting charge plates inches away from the "generator" makes sense.

@duane voth My BEV and others routinely absorb 100% of the energy from deceleration regen.

Maybe a hybrid's much smaller battery can't handle the current, but even my tiny 24kWh can, as can the same one in an eGolf.

It even becomes a slight safety issue in some cars when the unused brake discs get a coating of rust, adding a few feet to emergency braking distance. My BEV applies friction brakes below 7mph, so that's not an issue. Others can just periodically deactivate regen momentarily by shifting to N while driving, & then brake to clean the discs.

We recover slightly less than 100% all the way back into the battery, but that's just due to inefficiency of the system, much like charging from the plug only puts about 85% of the total grid energy into the battery of my car.