To date, the challenge with using high Ni cathode materials is that they tend to suffer from rapid capacity fade and impedance rise due to deleterious reactions between the Ni atoms on the surface of the cathode and the cell’s electrolyte. Many of the research projects are focused on high Ni materials, which exhibit very good energy density. Department of Energy (DOE), through the Vehicle Technologies Office, has committed to a multi-year, multi-thrust program to address all the scientific and engineering issues with eliminating most of the Co in EV batteries. Many technological hurdles exist, and the U.S. Industry has recognized the risks of Co dependency, and many battery manufacturers and end users have established ambitious goals to move to low- or no Co-containing cathodes. Despite how good the transition metal oxide-based cathodes, usually abbreviated NMC for the three majority transition metals followed by the Ni/Mn/Co ratio, have become for EV batteries, there is a globally recognized need to reduce dependence on Co without sacrificing performance. Moving away from high Co content means the new cathode materials must be optimized for all of these performance characteristics via subtle changes in the arrangement of the transition metals and their relative compositions. ![]() However, simple cobalt oxide offers the best mix of providing a high voltage, yielding very good energy density, and moving Li+ ions around easily. Three different transition metals-Co, manganese (Mn), and Ni-can manage the brunt of the charge storage shifts, and many other metals including aluminum (Al), titanium (Ti), iron (Fe), and magnesium (Mg) help. Therefore, the United States is looking to secure sources of Co, to drastically reduce the Co content in LiBs, or both. ![]() Moreover, the United States does not have large reserves for Co, and the extraction and early stage processing is concentrated in a small number of countries outside the United States. This means the supply is not independent of other commodity businesses and introducing new recovery projects is expensive. Cobalt is mined as a secondary material from mixed nickel (Ni) and copper ores. There are economic, security, and societal drivers to reduce Co content. Right now, Co can make up to 20% of the weight of the cathode in lithium ion EV batteries. EV batteries can have up to 20 kg of Co in each 100 kilowatt-hour (kWh) pack. Electrifying the worldwide automobile fleet with LiBs, however, changes the situation significantly.Ĭobalt is considered the highest material supply chain risk for electric vehicles (EVs) in the short and medium term. Even with the rise in cell phone use, this reliance on cobalt had not been a major hinderance, since only a small amount of Co was needed for these devices. The best combination for many energy storage needs involves a cathode structure that is largely composed of cobalt (Co) ions. In order to get enough energy from the batteries, LiB cathodes are made of various combinations of transition metals and oxygen in a particular arrangement. This is the cathode, and it’s also the place that lithium ions come from when the battery is charged. To work, these energy storage devices must have a place for the lithium ions to move to when the battery is working. ![]() Lithium-ion batteries (LiBs) are the ubiquitous power supplier in all consumer electronics, in all power tools and-as many companies and countries pursue greenhouse gas emission reduction goals-a growing proportion of the global light-duty automobile fleet.
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