We start today with an unusual proposition: newly redesigned battery packs for used Tesla Roadster electric cars. We've also got stories on Mazda's upcoming (Japan-only) diesel hybrid, and why Chevrolet Volts aren't very efficient in fleet use. All this and more on Green Car Reports.

Elon Musk hints at a replacement battery pack for the Tesla Roadster that could yield a 400-mile range.

The Polaris Slingshot has 173 horsepower and costs around $20,000, but is it a three-wheeled motorcycle, or a stripped-down car?

Find out why Chevrolet Volts in fleet use might as well not have a plug.

Mazda will offer a diesel hybrid in Japan, but U.S. diesels are still missing in action.

Electric boats have been around for more than a century but, as with cars, they're attracting renewed interest because of several different benefits.

Saab's new owner is still having financial trouble, leaving its future electric-car plans in doubt.

Finally, we list the most expensive states for car owners.


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