Considering all of the aftermarket companies that are popping up that will convert your Prius to a Plug-in Hybrid Electric Vehicle (PHEV), have you wondered why auto manufactures aren’t rolling PHEVs off the assembly line yet? I know I have. I’d really like to own a PHEV – the idea of a car that can drive around in town for 40 or 50 miles without firing its gasoline engine just seems really cool to me. So where are these PHEVs? Some people are accusing the auto manufacturers of dragging their heels, but the real problem lies in the same thing that powers your laptop – the lithium ion battery. You see, while a lithium ion battery usually does a good job of powering a laptop, cell phone, or power tool, have you noticed how these batteries lose performance after a few years. Heck, my cell phone is only 18 months old and its battery has gone from lasting almost 7 days to just over 2 days. In the world of automobiles, long term battery performance like that of a cell phone is completely unacceptable. Automobile manufacturers need the batteries to last at least 10 years or 150,000 miles before you start seeing them. Fortunately, several companies, such as A123Systems, are getting close to reaching those figures, so that hurdle is about to be cleared – likely sometime in 2007. The next major hurdle to jump is the safety of the batteries. I think just about everyone heard about the Dell battery recall last year. A battery that starts on fire in a laptop is major inconvenience; however, a battery that starts on fire while you’re driving 70mph down the Interstate can be a disaster. Lithium ion battery safety is the next big issue that’s keeping PHEVs from becoming production vehicles. The last one is one of simple economics – price. Currently, converting a Hybrid Electric Vehicle, like a Prius to a Plug-in Hybrid Electric vehicle will run you about $6,000 in parts, and that’s in addition to the premium you pay for the Prius. For production cars, you can initially expect the PHEVs to cost about $10,000 more than its conventional counterpart. Once production increases, that number will increase, but initially, there’s a much higher price to pay for a PHEV. So while the technology is nearly ready (a lot closer than hydrogen), there are legitimate reasons why you’re not seeing Ford, GM, and Toyota introduce PHEVs to the market just yet. They’re coming, and soon, but for you if you want a PHEV, you’ll either have to do it yourself or have an aftermarket conversion company, like Hybrids Plus, to do it for you.