ARGONNE, IL – Toyota Motor Corp. is moving ahead with plug-in hybrids, electrical vehicles and lithium-ion batteries, but it isn’t ready to abandon the tried and true, says one of the auto maker’s top researchers.

Toyota is the world’s hybrid-electric vehicle leader, having sold some 1.5 million HEVs worldwide – all based on more mature nickel-metal-hydride battery technology, notes Noburu Kikuchi, director of the Ann Arbor, MI-based Toyota Research Institute of North America.

The auto maker’s goal is to begin selling 1 million HEVs annually in the next decade and to offer hybrid powertrains in every vehicle in its lineup in 2020-2030, he tells a conference on Li-ion battery technology held on the grounds of the Department of Energy’s Argonne National Laboratory complex here.

But what percentage of those will be built with more advanced and still largely unproven Li-ion batteries, “I really can’t say,” Kikuchi says.

Toyota will roll out a plug-in Prius HEV for testing in 2009 that will use Li-ion technology, putting it among the first major global auto makers to do so.

The PHEV concept makes sense, Kikuchi says, because it allows the vehicle to utilize electricity without a change in the energy infrastructure. He says in Japan, fuel costs could be cut 21% with a PHEV compared with a conventional vehicle, or as much as 41% if all of the recharging is done at night during off-peak hours in electricity demand.

“But in the near future, if you look at it realistically, we have accumulated so much technology in NiMH that simply giving up (on that) might not be a good idea,” Kikuchi says.

Kikuchi also says Toyota “can’t ignore the internal-combustion-engine part” as it looks for cleaner-running, more fuel-efficient technologies.

“Toyota is making many improvements” to its ICEs, he says. “We are not giving up effort on this side.”

But he says hybrids offer a better prospect in reducing carbon-dioxide emissions, estimating the 1.5 million Toyota HEVs in operation translate into a 7 million-ton (6.3 million-t) reduction in CO2.

“There are many reasons” for pursuing plans to offer hybrids throughout the lineup, he says. “It’s not just fuel economy, it’s environmental.”

Even though Toyota took its battery-powered RAV4 off the market in the late 1990s, Toyota continues to pursue electric-vehicle technology as well, Kikuchi says.

The RAV4 EVs (and E-com concept experimented with in Japan) were abandoned because they didn’t have a long-enough cruising range, cost too much and took too long to charge. There also was a lack of a dedicated charging infrastructure, he says, a situation that continues today.

“The battery was not quite enough, so we had to give up,” Kikuchi says. “But that doesn’t mean we gave up forever.”

He says work on a new generation of EVs has been accelerated and they’ll be on the market “in the near future,” likely sometime around 2010.

“But for that, we really need your assistance,” he tells battery developers in attendance. Batteries “must be dependable and not only offer safety but low cost.

“We need a Li-ion battery that can be superior to the NiMH batteries we’re now using.”