Take for example the Castagna Milano's Mini Cooper hybrid conversion. Originally founded about a 150 years ago in Milan, Italy to build custom coaches for the wealthy nobility, Castagna now specializes in one-of-a-kind automobiles and specialty conversions. This year, they took the wildly popular BMW Mini Cooper and turned it into a plug-in hybrid.
Rather than go to the expense of having to engineer a hybrid drive like you'd find in the Prius or Escape, they simply left the transverse, IC engine in place under the front "bonnet" (hood for us Yankees). Instead, they re-engineered the rear axle and beefed up the car's suspension, installing an electric motor to drive the rear wheels at the flip of a switch by the driver. I am told that the battery is a ZEBRA sodium nickel chloride from MES DEA in Switzerland and that the company has warranted it for five years.
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