The share of electric vehicles (EVs) sold in the U.S. increased slowly but steadily over the last five years. Last year, 8% of all vehicles sold were either electric or plug-in hybrid, which was only 2% in 2019. A similar trend can be observed globally and it is expected to continue to increase. 

As we need to make batteries for millions of such vehicles, the availability, security and supply chain of materials for making up the battery is becoming a concern. A lithium-ion battery is most widely used in such vehicles. Let’s take a look at what comprises a lithium-ion battery.

It is an electrochemical cell consisting of an anode, cathode, an electrolyte, a separator and two terminals (positive and negative). The anode is made of graphite, while the cathode is made of lithium metal oxides or transition metal oxides like lithium cobalt oxide (LiCoO₂), lithium iron phosphate (LiFePO₄) and lithium nickel oxide (LiNiO₂). The electrolyte is a lithium salt (lithium hexaflurophosphate, LiPF₆, is most commonly used) in an organic solvent like ethylene carbonate, although others are also used. When the battery is discharging or powering the vehicles, the electrolyte carries positively charged lithium ion from the anode to cathode creating collection of electrons at the anode. The electric current then flows from the anode to cathode through an external device like electric motor.¹ The lithium-ion batteries are preferred today over nickel metal hydride batteries because of their high power-to-weight ratio, high energy efficiency, good high-temperature performance, long life and low self-discharge. 

The big automotive companies started making batteries in collaboration with battery suppliers and, therefore, focusing on availability, sourcing and supply chain of critical metals like lithium, cobalt and nickel. The same applies to rare earth elements as automakers started making their own electric motors. The performance of electrified vehicles relies on electric motors generating a strong magnetic field. The strongest permanent magnets are made with rare earth materials, with neodymium magnets. The most common magnet material is neodymium iron boron (NdFeB) because of its high energy density and available commercially, resulting in smaller batteries and making vehicles lighter. The other materials are samarium cobalt (SmCo), alnico (aluminum nickel cobalt) and ferrite (ceramic magnets) depending on specific application needs.


Figure 1. Top three countries of producing selected metals and fossil fuels in 2019.⁴ 

A typical EV battery (NMC532) contains roughly 8 kgs (17 lbs.) of lithium carbonate, 35 kgs (77 lbs.) of nickel, 20 kgs (44 lbs.) of manganese and 14 kgs (30 lbs.) of cobalt.² An EV contains between 2 kgs and 4 kgs of permanent magnets.³ Figure 1 shows the top three producers of such critical metals in the world. Other than rare earth materials (although second), the U.S. is not among the top producers of these critical materials. Even interesting is China dominates in processing volumes (meaning refining, and preparing them for industrial applications) of lithium, cobalt, nickel and rare earth metals. Given the geopolitical situation in the world today, the U.S. is in a disadvantageous position in securing these critical materials. Therefore, individual automotive companies are going ahead on their own in making multiyear deals with mining and refining companies domestically and also with foreign companies. The security of supply of such materials has gotten to such a point that the topic is discussed in exchange for the military security and peace guarantee of a nation as seen recently in U.S.-Ukraine interactions, and trade discussions with African countries. 

REFERENCES
1. www.energy.gov/energysaver/articles/how-lithium-ion-batteries-work
2. https://energyx.com/blog/where-do-electric-vehicle-ev-batteries-come-from
3. www.gknpm.com/en/products/permanent-magnet-solutions/ 
4. www.canarymedia.com/articles/clean-energy/minerals-and-the-clean-energy-transition-the-basics-2