Front wheel regenerative breaking

[FreepZ]

Chip Yates has a patent for a front wheel regenerative breakingbraking.

http://www.asphaltandrubber.com/news/front-wheel-kers-chip-yates-patent/

Front wheel regenerative breaking makes sense as the front wheel is where most of the breaking happens on a bike. Getting it to work reliably is going to be tricky.

[Edit: Well darn, I can't spell.  ]

[Brammofan]

1. He had this system on his "world's fastest electric superbike" but never hooked it up when the bike was moving.
2. Dude.... if your front wheel is breaking, you're going to have a bad time.  What you really want, is for your front wheel to be braking. 

[860]

Chip Yates has a patent for a front wheel regenerative breaking.

http://www.asphaltandrubber.com/news/front-wheel-kers-chip-yates-patent/

Front wheel regenerative breaking makes sense as the front wheel is where most of the breaking happens on a bike. Getting it to work reliably is going to be tricky.

It all depends on the "C" rating of your batteries.  The battery can only be charged so fast, so if you have relatively slow charging batteries, rear wheel regenerative braking can produce 100% of the charging rate of the battery.  If you have front wheel regenerative braking, and braking produces more electricity than your battery can handle, then having the regen on the front brakes won't recharge the battery anymore than a rear wheel system would.


The other benefit of a rear-wheel system is that you can tune in automatic regen without having to apply the brakes.  Just letting off the throttle can be tuned to give something similar to V-twin gas engine compression braking.  That wouldn't work too well with a front wheel regen system.


There are definitely pro's and con's for either system.

[FreepZ]

To take advantage of the energy that you get from heavy braking on the front wheel the bike would need to have a battery that can charge extremely fast (which doesn't exist right now) or capacitors. The problem with capacitors is that they aren't dense enough, and there isn't enough space on a bike for them.

Perhaps one day it will be possible to get all (or as much as the laws of physics allow) of energy lost to braking. Until then, rear wheel regenerative braking is better than nothing, and does okay at simulating engine braking.

[protomech]

My 13 year old Honda Insight has NiMH cells which can charge at 10C (50A for 5 Ah battery).

There are lithium blends that claim up to 10C fast charge; the problem is that the high-charge batteries tend to be lower capacity.

So you end up with something like a 10 kWh pack + 2 kWh gained from regen vs a 14 kWh high-energy (or blend) pack + 0.5 kWh gained from regen..