The top three battery makers for electric cars today are Panasonic, AESC, and LG Chem.
But while Panasonic sells largely to Tesla, and AESC is a joint venture half-owned by Nissan, LG sells its cells to more carmakers than any other battery company.
And the secret to that success is LG's expertise in chemicals and materials science, according to Prabhakar Patil, CEO of the LG Chem Power battery unit.
DON'T MISS: Battery Maker LG Chem: Biggest Electric-Car Winner Of All? (Aug 2014)
In a lengthy interview with ChargedEVs that's worth reading in full, Patil notes that both Panasonic and NEC (Nissan's partner in AESC) are consumer electronics companies.
LG Chem's decades of experience in researching, formulating, and developing chemicals, he suggests, gives his company the necessary background to make steady, incremental advances in cell chemistry as its core expertise.
The company has more than 400 engineers in South Korea working on every aspect of the materials science that goes into battery cells.
Autoline electric-car battery panel: Brett Smith, Prabhakar Patil, Ann Marie Sastry
Patil says that the progress made between 2010, when the first Chevy Volt went on sale, and the batteries he forsees in 2017, has been faster than he anticipated back then.
"There is not one thing you can point to and say, 'That’s what the breakthrough was,' ” he told ChargedEVs.
"It’s a combination of several things."
ALSO SEE: Nissan's Electric-Car Battery Future: Will It Be With LG Chem? (Sep 2014)
Patil expects that a $30,000 electric car with a range of 200 miles will be commercially viable by 2017 or 2018.
While GM hasn't confirmed that its upcoming 2017 Chevrolet Bolt EV will use LG Chem cells, that is widely assumed to be the case--and the Bolt EV to be the car he refers to.
(The Bolt's price, as announced by GM CEO Mary Barra in January, is actually $37,500 before a Federal income-tax credit of $7,500.)
Chevrolet Bolt Concept - 2015 Detroit Auto Show live photos
Patil says the short timeframe for the huge improvements in batteries to make that happen "has surprised me."
He also lays out the differences in the power-to-energy ratio between cells for hybrids and those for electric cars.
Hybrid batteries need very high power, but don't hold much energy, because they're cycled frequently; electric-car batteries must hold enough energy to move the car for 70 to 200 miles or more, but each cell is less powerful to optimize its energy capacity.
MORE: Electric-Car Battery Costs Already Cheaper Than 2020 Predictions: Study
LG Chem makes both kinds, Patil notes, but the power-to-energy ratio can vary by as much as 100 times at the two extremes.
LG Chem's battery cells can now be found in vehicles from Audi, Chevrolet (most notably the Volt), Ford, Hyundai, Renault, Smart, Volkswagen, Volvo, and others.
Both AESC and Panasonic have produced a higher total energy capacity for electric-car batteries than has LG Chem, thus far.
AESC lithium-ion cell
AESC has made more batteries, simply because Nissan is closing in on its 200,000th Leaf, more than double the next highest-volume competitor.
Panasonic, meanwhile, has made more cells because the battery pack in each Tesla Model S cars is roughly three times as large as that of today's Leaf.
Back in April 2011, LG Chem said it had opened what was then the world's highest-capacity battery plant, in Ochong, South Korea.
Chevrolet Volt Battery
It has since added a plant in Holland, Michigan, that supplies the Chevy Volt and the low-volume Chevrolet Spark EV.
Whether LG Chem can achieve the goal it announced in 2011--of capturing 25 percent of the global market for advanced automotive cells by 2015--remains to be seen.
But it seems safe to say that the company has already entered the top tier of plug-in electric car battery suppliers.