Great question! The answer: If you had the Volt's ICE in your car without the help from the battery the performance would be horrible. People don't realize it but you only need about 20 hp to keep an aerodynamic car moving at a good speed on the highway. You need the burst of energy from the battery (much higher than 55 kW) to give you the good performance. They didn't do it before because battery technology was too expensive.
I have a little secret for you. Don't repeat it too loudly because the other posters will run me out of town. Using the Volt's ICE and hooking it up to a standard transmission to the Volt's wheels would give you better mileage on the highway then going from the ICE to the gen-set to the electric motor (assuming no battery - weigh of both cars are identical). Other posters will yell and scream but it's true! "How can you say that Texas, have you gone crazy?" No. It's just that the efficiency losses are greater for the ICE - Generator - electric motor - drive linkages - wheels than ICE - standard transmission - drive linkages - wheels. Crazy stuff. Huh? I didn’t even bring up the fact that the generator and motor are heavier than the standard transmission. Ouch!
I have a little secret for you. Don't repeat it too loudly because the other posters will run me out of town. Using the Volt's ICE and hooking it up to a standard transmission to the Volt's wheels would give you better mileage on the highway then going from the ICE to the gen-set to the electric motor (assuming no battery - weigh of both cars are identical). Other posters will yell and scream but it's true! "How can you say that Texas, have you gone crazy?" No. It's just that the efficiency losses are greater for the ICE - Generator - electric motor - drive linkages - wheels than ICE - standard transmission - drive linkages - wheels. Crazy stuff. Huh? I didn’t even bring up the fact that the generator and motor are heavier than the standard transmission. Ouch!
