TR: Some think that recent innovation in lithium battery chemistry will improve performance and range with safer materials. Why is Toyota sticking with the older lithium cobalt oxide chemistry for its plug-in Prius?
MT: Battery reliability comes not only from the battery materials, but also from production know-how. So far, that chemistry gives us the highest total reliability.
TR: Will the commuter EV promised for 2012 use lithium cobalt oxide as well?
TR: Are you developing manufacturing know-how to increase the reliability of other battery chemistries?
MT: It’s not our intention to always adhere to the current chemistry. Batteries must keep on evolving. Reliability is not the only important feature. We also have to reduce cost and make them smaller.
TR: You recently promised to launch a fuel-cell commercialization effort by 2015. Why stick with fuel cells given the energy intensiveness of hydrogen production?
MT: Both electricity and hydrogen can be produced from any primary energy source, so from an energy security standpoint, they are both desirable fuel. And currently, electric power produced from fossil fuels produces a lot of CO2. But you’re right. We have to continue to discuss what source we use for hydrogen [to ensure its sustainability].
TR: What advice do you have for the next generation of engineers interested in transportation?
MT: They need to get “hands-on,” as we say within Toyota. There are very few young people interested in mechanics now, and I’m very concerned about this. People talk about software-driven products. Software may control the hardware, but you cannot come up with a good product just by studying software. In the end, it’s the hardware–the machine–that makes the product move.