Inside Lexus Hybrid Drive, Part 1

Lexus Hybrid Drive boss Shinichi Abe kicks off a three-part series on the ins and outs of Lexus hybrid technology.

Editor’s note: Five years after the Lexus Hybrid Drive system helped change the luxury auto industry, major things are happening in Lexus’ hybrid technology realm. Consider this past year: an RX 450h redesign, an HS 250h launch, and an LF-Ch debut. So it’s a good time to take a closer look at the system: chances are, it will factor more and more into your dealership decisions. In this first part of our Lexus Hybrid Drive series, Lexus hybrid boss Shinichi Abe looks back on how the system came to be—so that he can later show you the future.

WHEN THE LEXUS Hybrid Drive project first received the green light in the early 2000s, Shinichi Abe, the man about to inherit the biggest thing at Lexus at the time, admits that he and his team shared a few nervous moments.

After all, all that was at stake was the opportunity to help change the luxury auto industry, which had yet to see its first “alternative” energy vehicle on the road. Not only that, Abe had an enormous decision to make: which of Lexus’ several models would get the first hybrid conversion? The flagship LS sedan? The sporty SC convertible? A new model entirely? In the end, Abe’s bold decision belied any initial nervousness.

He chose an SUV.

The result, of course, was the RX 400h, the world’s first ever luxury hybrid vehicle, and a major surprise to many. Weren’t SUVs the opposite of good fuel economy? But to Abe, the decision made perfect sense. “The emphasis was on good fuel economy and low emissions, but also driveability. You do need power in an SUV and we couldn’t have one that drives slowly, could we?”

Abe’s move resolved an automotive paradox: strong performance no longer came at the price of decreased fuel economy and high emissions. In other words, the RX 400h’s new Lexus Hybrid System not only added a fuel-efficiency factor with electric-only power at low speeds—it actually boosted power during hard accelerations by combining the electric motor and gas engine. Lexus drivers could have it all.

And they kept getting it. Over the next four years, Abe and the RX 400h paved the way for an entire family of luxury hybrid sedans, first the Lexus GS 450h in 2005—the world’s first hybrid luxury sedan—and then the LS 600h L in 2006.

With these next hybrids came a new set of challenges, Abe explains. Specifically, these cars needed to be capable of higher speeds than the RX 400h—maximum speeds of more than 150 mph were required to meet customer wishes for Lexus’ top-tier sedans. So Abe and his team developed a transaxle with a smaller and longer motor incorporating a two-stage (high and low) speed-reduction device that functions as a pair of extremely wide-ranging gears.

It’s a beautifully compact solution that allows the Lexus Hybrid Drive transmission to fit in the floor tunnels of the GS 450h and the LS 600h L, like a conventional automatic. It also ensures hugely responsive and extraordinarily smooth power.

Abe recalls, “When I first drove the LS hybrid prototype in 2005, I felt a nonstop speeding up, which was incredible. It felt like being in a jet plane that’s taking off. With conventional gearing, I would have felt the steps between shift changes, but there was none of that, just seamless acceleration. It was a whole new world. It’s hard to put it in words; you only really understand when you try it for yourself.”

It’s not just about phenomenal acceleration, of course. The transmission in every Lexus hybrid, controlled by a harmonious balance of the driver’s wishes and computer software, contributes to an all-around optimal driving experience that embodies Lexus’ four hybrid-vehicle pillars: cleanliness, quietness, fuel efficiency, and fun.

He notes that things are again progressing, most recently with the 2010 RX 450h and HS 250h, which both have the latest-generation Lexus Hybrid Drive system technology, such as a super-efficient Atkinson cycle engine.

As for the future, Abe says that the aim is to have a hybrid version of every model by 2020, and for the cars to be in the same pricing ballpark as those with conventional transmissions.

He admits, “Honestly speaking, this is not what we thought at the beginning, but we have adapted in this direction in our evolution process. We need to do something about the energy crisis. We need to meet new demands. Lexus Hybrid Drive can help do that.”