Exclusive Interview With Honda’s Chief Engineer – Part 2: More on The Ultracapacitor

Editor’s Note: This is part two of an interview Tetsuya Yokoyama recently had the opportunity to conduct with Honda R&D Chief Engineer, Mr. Yamamoto, at Eco-Products 2008 in Tokyo, Japan. You can read part one here. Mr. Yamamoto is greatly involved in the development of Honda’s hybrid technology including the upcoming 2009 Insight.

Honda Insight Concept Left-side


As I mentioned in part one of my interview, Honda first introduced the ultracapacitor with the J-VX concept. The J-VX ultimately led to the original production Insight, without the ultracapacitor. Honda also used the ultracapacitor technology on the FCX models (pre-Clarity) for years.

Honda developed their original ultracapacitors, and improved them during the period of FCX development and explains more about it on their web site.

Regarding the cost of producing an ultracapacitor, Mr. Yamamoto pointed out that the ultracapacitor in fact has a great advantage. It could be made of carbon-based materials and require no use of rare metals, which means adding no significant production costs.

He also discussed the potential of using of both a standard battery and an ultracapacitor in the same system. Such a system could be possible by linking the battery and ultracapacitor in parallel, and it would have a great potential to take advantage of the strength of both technologies.

For example, giving the ultracapacitor a role as a start up device for the engine would be beneficial to reduce battery deterioration, especially for vehicles with an idling stop function, which require more frequent start ups. In recent years, in Europe, we see more vehicles with an idling stop system to reduce fuel consumption. Honda and other manufactures are looking into such a configuration.

Furthermore, some battery makers are developing the system combining both battery and ultracapacitor technology into one unit. They put the ultracapacitor technology inside of the battery system itself rather than linking them parallel.

A significant technological break through is rare. However, the accumulation of know-how from the continuous technological research and development could bring further advancement by linking different technologies together, he pointed out.

I’ll post part 3 of the interview soon, so stay tuned to Gas 2.0 for more.

Exclusive Interview With Honda’s Chief Engineer Segments:

Related links at Honda website:

Other Related Posts:

Honda Booth Honda Insight Concept Mr.Yamamoto and Yokoyama

Honda Booth at Eco-Products 2008. Mr Yamamoto and me on the right

* Please note that my interview with Mr. Yamamoto was conducted in Japanese and this post represents my best effort at translating his Japanese into English. Keep in mind that some of my translation may express a slightly different meaning from what Mr. Yamamoto intended to explain, and I may have a misunderstanding on some technical topics because I have no technical education in this subject. Please feel free to point out if you find an incorrect description. I do appreciate it because my intention of writing this article is to share correct information on this interesting topic.

Image Credits: M. Koguchi

Tetsuya Yokoyama

Originally from Kanazawa, Japan, Tetsuya graduated with honors and distinction in major from the University of California, Santa Barbara in Environmental Studies, and also completed a Global Operations Management certification program at the University of California, Irvine. He loves biking and playing soccer, and very interested in all kinds of green products and services. He used to drive his beloved hybrid car, Honda Insight in Southern California. Tetsuya currently writes about green matters from Tokyo, Japan. He hopes to make our planet a little more human and environmentally friendly place by spreading and sharing green stories.