Korean battery-makers are betting on North American production, chemistries to carve out an edge in ESS market BYD’s battery energy storage systems in Bisha, Saudi Arabia (Ministry of Energy of the Kingdom of Saudi Arabia) The global race for artificial intelligence is running into an unexpected bottleneck: electricity.As AI data centers drive a surge in demand for energy storage systems, the US is confronting an uncomfortable reality. Powering its AI ambitions increasingly depends on lithium iron phosphate, or LFP, batteries — a technology overwhelmingly dominated by China.Despite Washington's efforts to reduce reliance on Chinese supply chains, Beijing retains a commanding lead in LFP batteries, which have become the global standard for ESS thanks to their low cost and strong safety profile.That leaves Korean battery-makers facing a difficult challenge. Having moved aggressively into LFP to capitalize on the AI-driven ESS boom and US efforts to diversify away from China, they still trail Chinese rivals in both technology and cost competitiveness.China's head start in LFPAccording to a senior researcher at a major Korean battery company, Chinese manufacturers have spent years refining LFP chemistry while Korean suppliers are only now scaling up production.With battery lifespan and safety already approaching practical limits, the next frontier in LFP development is energy density — packing more active material into the same amount of space.Most major Chinese manufacturers have already mastered fourth-generation LFP technology, achieving electrode densities of around 2.4 grams per cubic centimeter, the researcher said. Industry leader CATL has moved even further ahead, mass-producing fifth-generation cells with densities reaching 2.6 grams per cubic centimeter."Korean manufacturers are effectively a generation behind," the researcher said. "While domestic players are still transitioning from third- to fourth-generation LFP, Chinese firms are already preparing fifth-generation products for large-scale energy storage projects."Closing the gap has become more difficult following China's export restrictions.In July 2025, Beijing added LFP and lithium manganese iron phosphate manufacturing technologies to its export control list, limiting overseas access to advanced know-how and samples."Korean companies cannot even obtain the latest Chinese LFP products for benchmarking and testing," the researcher said.A widening cost challengeIndustry estimates suggest Korean battery-makers face at least a 50 percent cost disadvantage compared with Chinese rivals. LFP cathode materials in China currently sell for just $5 to $7 per kilogram, levels Korean manufacturers struggle to match."We may eventually narrow the technology gap, but matching China's cost structure could prove extremely difficult," an industry official said.China's advantage stems from its control of the entire supply chain, from iron phosphate precursors to lithium refining and battery manufacturing, allowing producers to minimize logistics and production costs.Scale further widens the gap.Leading Chinese material suppliers are rapidly building megafactories with annual production capacities exceeding 1 million metric tons. Companies such as Hunan Yuneng, Wanrun New Energy and Dynanonic are approaching that threshold, with at least five Chinese producers expected to surpass it by 2027.By comparison, Korean suppliers are projected to have a combined capacity of between 200,000 and 400,000 tons.China dominates ESS marketThe imbalance is already visible in the global market share.According to InfoLink Consulting, seven of the world's top 10 ESS battery suppliers by shipments in the first quarter were Chinese companies, including four of the top five. Korean companies failed to make the list.Still, Korean battery-makers see opportunities as the market expands rapidly alongside AI infrastructure investment and power demand.The industry is pursuing a two-track strategy: expanding LFP production in North America to capture near-term demand while investing in next-generation chemistries for a longer-term premium edge.LG Energy Solution has begun mass production of ESS LFP batteries in Michigan and is expanding output through its US joint venture with Honda. Samsung SDI plans to begin production at its Indiana joint venture with Stellantis later in the year, while SK On is preparing to launch output at its Georgia facility.Looking beyond LFPIndustry officials believe the next battleground lies beyond conventional LFP.Potential successors include lithium manganese-rich batteries and LMFP, which use higher manganese content to improve energy density while maintaining cost advantages.The strategy mirrors Korean battery-makers' approach in electric vehicles, where they established a premium position through nickel-cobalt-manganese batteries rather than competing solely on cost.However, competition is expected to remain intense. Chinese manufacturers are already commercializing LMFP technology, while Korean firms are investing heavily in next-generation batteries and North American production capacity in an effort to carve out a differentiated position as the ESS market matures.