Elon Musk earlier this week made his most bullish statements yet on iron-based batteries, noting that Tesla is making a “long-term shift” toward older, cheaper lithium-iron-phosphate (LFP) cells in its energy storage products and some entry-level EVs.

The Tesla CEO mused that the company’s batteries may eventually be roughly two-thirds iron-based and one-third nickel-based across its products. “And this is actually good because there’s plenty of iron in the world,” he added.

Musk’s comments reflect a change that is already underway within the automotive sector, mainly in China. Battery chemistries outside of China have been predominantly nickel-based — specifically nickel-manganese-cobalt (NMC) and nickel-cobalt-aluminum (NCA). These newer chemistries have become attractive to automakers due to their higher energy density, letting original equipment manufacturers (OEMs) improve the range of their batteries.

If Musk’s bullishness is heralding a genuine shift across the EV industry, the question is whether battery makers outside of China will be able to keep up.

Musk is not the only automotive executive to signal a return to the LFP formula. Earlier this year, Ford CEO Jim Farley said the company would use LFP batteries in some commercial vehicles. Meanwhile, Volkswagen CEO Herbert Diess announced during the company’s inaugural battery day presentation that LFP would be used in some VW entry-level EVs.

On the energy storage front, Musk’s comments about using LFP-based chemistries in Powerwall and Megapack are in line with other stationary energy storage companies pushing for iron-based formulas. “The stationary storage industry wants to move to LFP because it’s cheaper,” Sam Jaffe, who heads the battery research firm Cairn Energy Research Advisors, told TechCrunch.

LFP battery cells are attractive for a few different reasons. For one, they’re not dependent on ultra-scarce and price-volatile raw materials like cobalt and nickel. (Cobalt, which is predominantly sourced from the Democratic Republic of Congo, has undergone additional scrutiny due to inhumane mining conditions.) And while they are less energy-dense than nickel-based chemistries, LFP batteries are much cheaper. This is good news for those looking to spur the shift to electric vehicles because lowering the cost per vehicle will likely be key to greater EV adoption.

Musk clearly sees a major future for iron-based chemistries at Tesla, and his comments have helped thrust LFP back into the spotlight. But there’s one place where they’ve remained the star of the show: China.

“LFP is pretty much only produced in China,” Caspar Rawles, head of price and data assessments at the research firm Benchmark Mineral Intelligence, explained in a recent interview with TechCrunch.

China’s dominance in LFP battery production in part relates to a series of key LFP patents, which are managed by a consortium of universities and research institutions. This consortium came to an agreement with Chinese battery makers a decade ago under which the manufacturers would not be charged a licensing fee providing that the LFP batteries were used only in Chinese markets.

Hence, China cornered the LFP market.

Battery makers in China may benefit most from a potential tectonic shift toward LFP — specifically BYD and CATL, the latter of which already manufactures LFP batteries for Tesla vehicles built and sold in China. (Volkswagen, meanwhile, has a substantial stake in Chinese LFP maker Gotion High-Tech.) These battery makers aren’t slowing down: In January, CATL and Shenzhen Dynanonic signed an agreement with a local Chinese province to build an LFP cathode plant at a cost of $280 million over three years.

The LFP patents are due to expire in 2022, industry analyst Roskill explains, which could give battery manufacturers outside China time to start shifting some of their production toward iron-based formulas. However, all of the planned battery factories in Europe and North America, many of which are joint ventures with South Korean industry giants like LG Chem or SK Innovation, are still focused on nickel-based chemistries.

“For the U.S. to take advantage of LFP’s strengths, North American manufacturing will be necessary,” Jaffe explained. “Everyone building a gigafactory in the U.S. today is planning on making high nickel chemistries. There’s an enormous unmet need for locally manufactured LFP batteries.”

Rawles said he expects some LFP capacity in North America and Europe in the coming years, particularly after the patents expire. He pointed out that both CATL and SVOLT, another battery maker, have been making moves in Germany — but both of these companies are Chinese, which leaves open the question of whether other Asian or Western companies can compete in the LFP market. (Stellantis chose SVOLT as one of its battery suppliers from 2025 onwards.)

On the energy storage front, Jaffe said he thinks “it’s inevitable that most stationary storage systems will eventually be LFP.”

However, not all is lost for domestic manufacturing in the United States. “The good news for building local LFP manufacturing is that the supply chain is simple: Outside of lithium, it’s iron and phosphoric acid, two cheap materials already made [in the U.S.] in large quantities,” Jaffe added.

In the end, it is not a question of one battery chemistry versus another. What’s more likely is what we’ve already started to see from automakers, including Tesla: Iron-based batteries will be used predominately in entry-level and cheaper vehicles, while nickel-based cells will be used for higher-end and performance cars. Many consumers will likely be content with a 200- to 250-mile-range vehicle that’s thousands of dollars cheaper than one with a range of 300 to 350 miles.

Automakers have also begun making moves to take control of the battery supply, whether through vertical manufacturing or joint ventures with established battery companies. That means that growing LFP capacity in North America and Europe is not only likely, but inevitable.