Chevy Volt Charging Strategy Redux

Illustration for article titled Chevy Volt Charging Strategy Redux

Edmunds Inside Line stirred up kind of a hornets nest yesterday when they reported the Chevy Volt won't use the engine to recharge the battery, spurring a similar story from us. Both of us were told by GM PR we were correct in making that assertion. Turns out the PR team was having the same problems both us and Inside Line were having in understanding how the Volt's engine/battery/motor system will work. GM's VP for Global Program Management, John Lauckner, rebuffing the initial claims, stated, in no uncertain terms, the engine can recharge the battery, but recharging the battery is not its objective. Whatever that means. All we know is engines are most efficient when operated at a steady state — tons of tricks can be implemented to optimize performance at a constant RPM, and that's the plan for the Volt.As with any steady-state output, sometimes there will be surpluses. Those surpluses of electricity not used by the electric motor, as might occur during light loads, will be dumped into the battery so that energy isn't wasted. But recharging the battery is not the objective of running the engine. In addition to extra electricity from the engine/generator, energy reclaimed from regenerative braking will also be stored in the battery. Over an extended period of these surpluses being added to the battery, it's possible for the engine to switch off and the car to return to all-EV mode for an unspecified distance. So, let's be clear here — contrary to the second set claims of GM PR on the Volt's engine — it can in fact recharge the batteries. You could almost say GM was for this claim before it was against it — and is now for it again. Stinkin' buncha flip-floppers.[Edmunds Inside Line]

Share This Story

Get our `newsletter`


Sounds like GM sold their ElectroMotive Division too soon. The diesel-electric locomotive guys have been doing this sort of thing for decades. Tons of expertise there.