Toronto-based Hymotion has unveiled unique plug-in kits for the Toyota Prius and Ford Escape Hybrid that it will initially be selling only to fleet customers. The plug-in kits add a supplementary pack of lithium-ion batteries to each vehicle’s original NiMH system. The new Li-ion packs tap into the vehicles regenerative braking to restore energy and can also be fed from the engine and the power grid when it’s plugged in. Aside from that each hybrid operates normally and would return to using its factory battery pack.

A Prius kit for fleet orders over 100 will cost about $9,500 CN or $8,286 US. Pricing hasn’t been announced for the Escape Hybrid plug-in kit, but Hymotion promises it will be 2.5 times more powerful than the Prius kit, and subsequently more expensive.