BMW AG is planning extensive tests on Mini-brand electric vehicles to explore the technology.

About 500 Minis are being prepared for evaluation. The cars, built in Oxford, England, will be modified and fitted for fleet trials in Munich. They will be powered by lithium-ion batteries.

“This step will allow the BMW Group to gain an initial knowledge of how mobility can be achieved efficiently using purely electrically powered vehicles,” BMW Chairman Norbert Reithofer says in a statement.

“Our task here is to combine the ultimate driving experience with an efficient electrified drive with practically no emissions.”

Reithofer says the results of the Mini EV tests will be used over the next 12-18 months to refine the technology, with details to be published near the end of the year.

The auto maker for several years has been conducting extensive fleet testing of hydrogen-based powertrains.

BMW in March said it would decide this year whether to develop an electric car. In doing so, it would join a number of other global auto makers including General Motors Corp., Volkswagen AG, Mitsubishi Motors Corp., Renault SA and Nissan Motor Co. Ltd.