Electric cars may still make up just a tiny percentage of the vehicles on world roads, but the batteries that power them are already a big business.

As with most industries, that occasionally means big lawsuits, as companies try to protect valuable intellectual property they've spent years or decades refining.

RELATED: Nickel-Metal-Hydride Batteries For Electric Cars? Energy Density Can Rise 10-Fold, BASF Says

Now, the battery industry is about to witness a lawsuit over a type of cell chemistry that could have major implications for electric cars.

It revolves around NMC--nickel-cobalt manganese--cathode material, which could help increase the performance of future electric-car battery packs, reports Quartz.

Filed in U.S. Federal Court in Delaware on February 20, the case pits Germany's BASF--the world's largest chemical company--against Belgium's Umicore, a major supplier of battery materials.

Battery pack assembly for 2015 Chevrolet Spark EV electric car at GM's Brownstown, Michigan, plant

Battery pack assembly for 2015 Chevrolet Spark EV electric car at GM's Brownstown, Michigan, plant

BASF accuses Umicore of selling NMC, even though BASF holds an exclusive license to it.

The lawsuit also claims Umicore threatened to sue other companies if they gave business to BASF, and seeks billions of dollars in alleged damages.

The case also involves two entities that are major players in the lithium-ion field--3M Corp. and the U.S. government-run Argonne National Laboratory.

SEE ALSO: DOE Awards $11 Million for Advanced Battery Technology (Jun 2009)

Argonne is listed as a co-complainant along with BASF in the suit.

In addition to Umicore, the suit also names Japanese toolmaker Makita, which is accused of obtaining NMC from the Belgian company.

The competing NMC interests go back to June 2000, when Michael Thackeray--a researcher working at Argonne--filed the first patent.

Battery pack assembly for 2015 Chevrolet Spark EV electric car at GM's Brownstown, Michigan, plant

Battery pack assembly for 2015 Chevrolet Spark EV electric car at GM's Brownstown, Michigan, plant

Three months later, 3M filed another patent on behalf of Jeff Dahn, of Dalhousie University in Halifax, Nova Scotia.

Thackeray's patent is only valid in the U.S., as Argonne did not anticipate NMC becoming commercially important at the time.

3M, on the other hand, obtained patents for Dahn's version of NMC in the U.S., China, Japan, and South Korea.

CHECK OUT: Electric-Car Battery Costs Already Cheaper Than 2020 Predictions: Study

The company has aggressively defended overseas patents, but apparently hasn't filed suit in the U.S.--where BASF and Argonne are now going on the offensive.

At stake is the future control of the NMC cathode material, which some experts believe can form the basis for cheaper yet more energy-dense battery cells.

Increasing energy density--and thus the potential range of a battery pack at a given size--while lowering costs could make electric cars attractive to more buyers.

Battery pack assembly for 2015 Chevrolet Spark EV electric car at GM's Brownstown, Michigan, plant

Battery pack assembly for 2015 Chevrolet Spark EV electric car at GM's Brownstown, Michigan, plant

Chevrolet Volt battery cells already use that chemistry, and it's possible General Motors could become entangled in this case.

Both Argonne and 3M-backed researcher Dahn claim the Volt cells use their respective versions of NMC.

The Quartz article provides more details on the suit and the specifics of the chemistry in question.

_______________________________________________

Follow GreenCarReports on Facebook, Twitter, and Google+.