A plug-in Toyota Prius for less than a regular Prius?

Good for just 70 mpg?

An extra 20 mpg

What’s it like to drive a Toyota Prius plug-in hybrid? What kind of fuel economy does it achieve? What’s the EV range? Time to charge, etc?

MotorTrend answers those questions today in a great article on the plug-in Prius and, well, the plug-in Prius drives pretty much like a regular Toyota Prius, while achieving an extra 20 mpg in fuel economy.

Big deal? Just 20 mpg more? Well, what if the plug-in Prius costs less than a conventional Prius?

Now, I’m not saying that’s going to happen, but according to the MotorTrend article, the lithium-ion battery pack in the plug-in Toyota Prius actually costs less than the NiMH battery pack in the conventional Prius. MotorTrend writes, “lithium-ion batteries presently cost something like $600 per kW-hr, meaning the PPI’s (Prius Plug-In’s) battery alone could run about $2000, less the price of its displaced nickel-metal hydride pack (price: $2729).”

Even if true, there is a more sophisticated battery management system, for instance, that also has to be factored into the costs, as well as a ton of new software. So, there will be additional plug-in costs beyond the battery.

Nevertheless, I’m befuddled. Not long ago Toyota stopped plans to switch to lithium-ion batteries in the third generation Prius because of additional costs. If a conventional Prius only needs 1.3 kwh of battery, wouldn’t lithium be much cheaper than NiMH at $800 for 1.3 kwh’s for lithium verus $2729 for NiMH? So, why did Toyota claim costs would be higher?

Anyway, I wonder, how many more would buy a Prius if they could achieve an extra 20 mpg for the same cost as today’s Prius? Would sales double, triple, more? Would having to plug-in to achieve this extra 20 mpg be too much of a burden for most Prius buyers? And, as a bonus question, would the plug-in Prius outsell the conventional Prius if the conventional Prius was $1500 cheaper?