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I have seen two articles that now mention "brake energy recuperation". I imagine that BMW furnished this information to the magazines. That implies that there is a motor on the wheel to return this recuperated energy to a battery. Which implies more weight.

What exactly are they recuperating the energy to? I hope this is just a translation/technical misunderstanding.
 

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l could be wrong but i think it's like hybrid cars when you brake, it activate the "small generators" in the wheel hub so to speak, to charge the battery and not constantly by the alternator in the engine which creates drag and robbs horsepower. using this you probably have smaller and lighter battery in place to save some weight.
 

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l could be wrong but i think it's like hybrid cars when you brake, it activate the "small generators" in the wheel hub so to speak, to charge the battery and not constantly by the alternator in the engine which creates drag and robbs horsepower. using this you probably have smaller and lighter battery in place to save some weight.
I think you're 100% right JCM5 and it's called Brake Energy Regeneration. I've also heard that alternator is much smaller. So, it doesn't seem that everyone knows about this yet even though I believe it started on the 7 (F01) in 2009. It just goes to show you that BMW throws it out there to the magazines because it's important. What they aren't doing it shoving it down the public's throat via an ever-so-clever marketing campaign designed to brainwash the public and sell more cars. *COUGH* toyotalexustrash *COUGH* Trendy! Follow the light, little ones!
 

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Wasn't it supposed to be a KERS, in the sense that it would store energy otherwise wasted as heat in braking and then let it be used later for a temporary increase in power?
 

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Wasn't it supposed to be a KERS, in the sense that it would store energy otherwise wasted as heat in braking and then let it be used later for a temporary increase in power?
Previous posters are mentioning Brake-regeneration systems which are for Hybrid powertrain cars

The M5 is said to have a KERS-like system (F1 derived) which takes the braking force and through some sort of magic puts it into some magic capictor and when you push a button you get extra power



It was said that the new M5 will have this feature but for various reasons I still highly doubt it. Lots of weight being the main limiting factor.
 

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Previous posters are mentioning Brake-regeneration systems which are for Hybrid powertrain cars

The M5 is said to have a KERS-like system (F1 derived) which takes the braking force and through some sort of magic puts it into some magic capictor and when you push a button you get extra power



It was said that the new M5 will have this feature but for various reasons I still highly doubt it. Lots of weight being the main limiting factor.
Check this out: Learn about The F1 KERS system 2009 Video
 

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I think the BMW system is actually pretty simple, and is based on an existing (E60) system that just didn't get as much eco-marketing spin.

Most car batteries "like" to stay fully charged via constant voltage from the alternator. In the E60, the battery is an AGM lead battery that can handle many charge/discharge cycles and, in particular, can "fast charge" via higher charge voltage without causing problems.

Even today, the E60 tells the alternator how much voltage/current to apply based on the charge state of the battery. I think the only "new" thing in the F10 is that (as long as the charge state is in a normal range), the alternator free spools (no load)--- or maybe there is a mechanical clutch, I'm not sure--- at ALL TIMES other than during braking (during which time it is fast charged). The resistance of the alternator charges the battery and adds a bit of engine/drivetrain braking.

The marketing department stretches a bit and calls this "regenerative braking," even though the stored electricity doesn't increase power (other than in the sense that a free spooling alternator gives you more TQ at the wheels).

I don't think the system has any extra batteries / supercaps / electric motors anywhere.
 
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