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Has Toyota delayed new Priuses? Is cobalt to blame?

Cobalt versus phosphate: the electric car world wants to know.

Bob Kanode, the CEO of Valence Technology, which makes lithium-ion batteries for vehicles, recently said one of the big issues for the electric car world was going to be cobalt versus phosphate. And he may be right.

A home-baked plug-in hybrid Tom Krazit/CNET

The Wall Street Journal (subscription required) has reported that Toyota has delayed a new generation of hybrid vehicles, including a new Prius, because of concerns about safety and reliability of the batteries inside them. These batteries are lithium cobalt oxide batteries, the same chemistry used in laptop lithium batteries. (Currently, Toyota hybrids use nickel metal hydride batteries.)

Toyota was supposed to start introducing the lithium-ion hybrids between 2008 and 2010, according to the Journal. Instead, it will continue with nickel metal hydride, the Journal states.

Toyota has hotly denied the allegations that it has delayed or changed its product line. However, it affirmed a position it has stated for some time: that there are safety and reliability issues with lithium-ion batteries. The official Toyota blog states:

"We have consistently affirmed that there are many issues that need to be resolved, beyond the safety and reliability of lithium-ion batteries, before a commercial lithium-ion-equipped hybrid--and what we're talking about here is the so-called plug-in hybrid, or PHEV--is ready for the market.

"These issues include battery cost, availability, performance and packaging. All of the carmakers face the same problems when it comes to these issues. The answers, unfortunately, are not just around the corner," the blog states.

This is not a new position for Toyota. Dave Hermance, a now deceased Toyota exec often credited with bringing the Prius to prominence, voiced similar concerns about plug-ins in an interview with me in 2005.

But back to Kanode. Valence, among other battery start-ups, focuses on lithium phosphate. These batteries don't back the same energy density as lithium cobalt batteries, but they are safer.

"Lithium cobalt for cell size will give you more energy," he said last month. "But by definition, lithium cobalt will never be safe."

If Toyota is in fact experimenting with lithium cobalt batteries, and is having problems, we may be witnessing a formula war coming to a head.

General Motors, by the way, is working with A123 Systems on a lithium battery. It is phosphate based. (Altair Nanotechnologies uses a similar chemistry.)