We've been covering the development of a new family of hybrids under the Prius umbrella at Toyota for several years now, and while it's still not official, a new report out of Japan today contains hints at a new Prius-branded wagon or SUV due out in late 2010.

Perhaps most interesting about the new hybrid is that it is expected to be Toyota's first with a lithium-ion battery pack. Mercedes-Benz was first to market with a consumer-grade lithium-ion hybrid with the S400 Hybrid, but even that vehicle is extremely low-volume compared to Toyota-brand products. The new battery is expected to be more powerful in order to deliver the extra oomph necessary to propel a larger vehicle.

The shift from nickel-metal hydride batteries comes with some other info, including a possible wagon or SUV body style and a starting price around $22,000. That's right on top of the current Prius's pricing, indicating that Toyota is targeting a different market with the new hybrid, not expecting to cannibalize the Prius sedan's sales figures.

Reports of Toyota's plans for a dedicated hybrid sub-brand extend back to at least 2007, and concepts released over the years, including the Hybrid X, have been thought to presage that brand's lineup. If the new Prius vehicle is indeed a wagon, expect it to share trates of the Hybrid X in its styling and proportions, though what a Prius SUV might look like is, at this point, anybody's guess.

When the lithium-ion technology might trickle over to Lexus and enable a more efficient full-sized hybrid above the HS is not known yet, either, though it would be a logical extension of such a program.

[Detroit News]