Greenlings: How do hybrids and electric vehicles blend regenerative and friction braking?

Following last week’s announcement by Toyota that it would recall several hundred thousand units of the 2010 Prius and Lexus HS250h to update the brake control software, there have been numerous questions about how these systems work. Vehicles with strong hybrid systems like those built by Toyota, Ford and General Motors all use an electro-hydraulic brake system that provides partial brake-by-wire control.

While there are detail differences in the implementations from each manufacturer, the basic operating principles are largely the same. The key to the efficiency advantage of hybrids is their ability to recover kinetic energy that is normally dissipated as heat when the vehicle is slowing down and then store and release that energy to provide propulsion later. This is known as regenerative braking, and we’re going to discuss aspects of regenerative braking that apply equally to pure electric and extended range electric vehicles like the Nissan Leaf and Chevrolet Volt. Read on after the jump to learn more.