Improvements in the energy density of electric-vehicles batteries have been driven by advancements in cathodes over the past decade. The next incremental gains in performance and cost are expected to come from emerging technologies in other components, including next-generation anodes, solid-state batteries and sodium-ion cells.
Aside from the technical advantages of certain materials, which include providing longer ranges and faster charging capabilities — hopefully at a lower cost — the move toward new battery materials is emerging as companies and countries grapple with the reality of just how much extraction will be required to make the clean transition.
The history of cathode innovation tells us that shifting away from materials that have more vulnerable supply chains is possible, and in fact, it enabled the move to lower cobalt content and toward chemistries with higher nickel content. The rate at which other emerging technology innovations are adopted could have a significant impact on demand for key raw materials like graphite and lithium.
In its latest
electric vehicle outlook,
BloombergNEF updated its
battery chemistry forecasts, which now include sodium-
ion batteries accounting for 3% of passenger car market
battery demand in 2035 and 30% of
battery demand in the two- and three-wheeler segment. Those sodium-
ion batteries, which don’t use
lithium, could help displace up to 7% of
lithium demand in 2035. While that percentage seems small, it equates to more than half of all the
lithium demand last year. The rush to secure
lithium resources in South America and Africa is just beginning, and any technology that can help offset or alleviate some of the demand will be in favor when (not if) there are supply crunches.
In an even more aggressive scenario, where sodium-
ion batteries are used in all small vehicles,
lithium displacement gets to 37% by 2035. This may be required if
lithium supply cannot meet the significant ramp-up in demand, especially if the amount in batteries increases with the use of
lithium-metal anodes enabled through solid-state electrolytes.
However, this scenario would require a rapid supply chain and manufacturing expansion, with sodium-ion cells in 2035 being more than twice the volume of lithium-ion in 2023, a scale that has taken decades to reach.
On the anode side, BNEF expects technologies that lean on silicon, lithium and hard carbon to start entering the battery market this decade, and estimates they could displace 46% of graphite demand in 2035 compared to a scenario in which the market doesn’t shift away from graphite.
Silicon-based
anode materials can have an impressive specific capacity up to 4,000 milliampere-hours per gram, over 10 times higher than natural and artificial
graphite. Challenges associated with silicon, such as volumetric changes during cycling, are being addressed by reducing particle size and adding conductive materials and pre-lithiation treatments. The other exciting contender for anodes is
lithium-metal, which have higher theoretical specific capacity than both silicon-based anodes and
graphite. These anodes, which have to be paired with more advanced electrolytes
, such as hybrid or solid-state electrolytes
, would add to the
lithium supply dilemma, in that they would create more demand.
