Toyota to lease Plug-in Gen III Prius Worldwide

Toyota is planning on leasing a very limited amount of Gen III (the newest) plug-in Prius. They’re sticking in Lithium Ion batteries instead of NiMH.
Only 500 Priuses worldwide (150 in the US) will be in this program, though we can always hope that this is successful and Toyota decides to expand the program.

The specifications include replacing the NiMH with a Li-ion pack that would allow the Prius to drive further on only electricity. How far? We don’t know. If we compare the size of the Gen III NiMH pack and assume the Li-ion pack is the same size (NiMH 1.3kWh at 200Wh/L or 6.5L), an equivalent volume Li-ion pack would offer about 2.1kWh and 50kW in a low energy-high power configuration (2000W/kg, 85Wh/kg, 25kg battery pack). At a 80% depth of discharge, the battery pack would provide about 7.5 miles of electric only driving, though that assumes that you stay below the 50kW threshold when driving – the electric only range might go from under 25mph to under 45mph for the first few miles while the battery has sufficient charge.

If the Prius doesn’t get an upgraded electric motor and sticks with its 50kW (67HP) motor, then the acceleration will be poor, however it will be capable of highway speeds (though on steep grades it might have some trouble and the engine will kick on regardless of the state of charge).

This is the logical evolution of the parallel hybrid paradigm, but its also the end of the line for the configuration. At some point using the gasoline engine and the electric motor in parallel loses out to a serial configuration because the electric motor is big enough and the battery pack can generate enough power as to only need the gasoline motor in a “power boost” situation, you might as well just not carry that weight for that purpose and carry the weight for a charge sustaining mode.

Possibly Related Posts:

• Lithium Math – Quick Update
• Lithium Supplies – Locked and Loaded
• Lithium-Carbon-Fluorine Battery Breakthrough?
• Mitsubishi Demonstrates Ultracapacitor – Hype or Holy Grail?
• Japanese group announces 10,000 cycle capacitors
• Predictions for 2010
• MIT Powerpoint on electric cars
• Nissan forging ahead on Batteries