The transition back to using lithium iron phosphate (LFP) cathodes in electric vehicle (EV) batteries from nickel manganese cobalt (NMC) poses a challenge to recyclers and could split the market, attendees at the Future Battery Forum in Berlin heard on Tuesday.
In the race to maximise energy density to support longer EV driving ranges, battery manufacturers largely adopted NMC cathodes, particularly outside China. NMC battery cells typically provide an energy density of about 250 Wh/kg, supporting a range of about 300 miles (480km) on a single charge, while LFP cells provide about 160 Wh/kg.
But concerns about the sourcing of cobalt from the Democratic Republic of Congo and nickel from Russia, where sanctions apply, have prompted manufacturers to look for alternative raw material sources. Another issue is that NMC chemistries can make battery cells susceptible to thermal runaway that causes fires, as well as shorter lifespans.
In this respect, LFP energy density can effectively close the gap with NMC at the battery pack level, as lower thermal runaway allows the cells to be packed closer together in the vehicle.
This shift back towards LFP battery chemistries has implications for recycling, according to Nuria Gonzalez-Garcia, head of research and technology at German firm Betteries, which upcycles EV batteries into portable power systems.
"LFP poses a huge challenge to recyclers because there are not these expensive and very relevant materials inside the batteries — there's no nickel, there's no cobalt," Gonzalez-Garcia said. "There's still lithium, there's still graphite, but the recycling process is more challenging. What happens to those batteries when they reach end of life? Do we recycle them?
Maybe the market splits into two different flows — the flow of low-value battery chemistry and those are radically reduced, and the other market flow which is NMC batteries or those with high content of cobalt and nickel which are of huge value for recyclers."
Low-value LFP batteries could be used in second-life applications, while higher-value batteries with high nickel content could be sent straight to recyclers, Gonzalez-Garcia suggested.
LFP chemistries accounted for 27pc of global battery capacity for light-duty vehicles in 2022, up from 17pc in 2021 and just 3pc in 2019, according to the International Energy Agency. High-nickel chemistries accounted for a 66pc share, down from 76pc in 2021 and 89pc in 2019. NCA accounted for a share of about 8pc last year.
The LFP transition is driven by China, which accounted for about 95pc of the LFP batteries produced last year. Just 3pc of light-duty vehicles with LFP batteries were manufactured in the US in 2022.
LFP market share could rise to account for about half of lithium-ion battery demand by 2030, according to consulting firm McKinsey, at just over 2TWh of the total 4.5TWh. The share of NMC could decline to just under 2TWh, with NCA accounting for less than 1TWh and other chemistries making up the remainder.
That would increase the challenge for recyclers to make a profit from extracting materials from spent batteries. Recycling of lithium-ion batteries via conventional recycling methods using pyrometallurgy and hydrometallurgy is largely unprofitable for LFP and lithium manganese oxide (LMO) batteries in Europe and the US, data show. Direct recycling, which reduces intermediate processing steps to recover a larger proportion of the metals and chemicals, is marginally profitable for LFP and LMO but NMC and nickel-cobalt-aluminium recycling generates about $10/kWh of profit in the US and Europe and closer to $20/kWh in South Korea and China. The importance of recovery rates will increase as more batteries reach the end of their life in the coming years and increase waste, while rising EV production will limit primary raw material supply.
