Without a super-efficient battery, Plug-in hybrid electric vehicles (PHEV) are little more than scrap metal. The more efficient the battery, the longer a car can run--and the more attractive it is to people who need to drive long distances. That's why Hitachi's announcement that it has developed the world's most efficient lithium-ion battery for hybrid cars--the newest battery of choice-- is so important. In the past, car companies have relied on clunky and inefficient nickel metal hydride batteries.

According to Japanese Web site Nikkei, Hitachi's battery has an output per kilogram of 4,500 watts--70% more than its current li-ion batteries and 50% more than a new model that will be released next year. The super-battery has a lifespan of 10 years, so it can stay put in a PHEV for life (or close to it). 

No word yet from Hitachi on pricing, but the battery, scheduled to be released in mid-2010, will almost certainly be more expensive than its less efficient counterparts. One thing is for sure, though. Li-ion battery makers like Johnson Controls-Saft and Blue Energy should watch their backs.

[Via CrunchGear]