Currently, the cathode accounts for 50% of the cost of producing a lithium-ion battery. Beyond economic considerations, iron-based cathodes offer the potential for greater safety and sustainability. As the transportation sector increasingly relies on lithium-ion batteries, global demand for nickel and cobalt has surged, leading to a predicted shortage of these materials. Additionally, the energy density of nickel and cobalt is already reaching its limit, and pushing beyond this limit could result in environmental contamination of ecosystems and water sources. Therefore, there is a need for new, more sustainable battery chemistries.
Iron, the most common element on Earth by mass, is the fourth most abundant element in the planet’s crust and is not at risk of shortage. Researchers have enhanced the reactivity of iron in their cathode by designing a chemical environment that incorporates a blend of fluorine and phosphate anions—negatively charged ions. Cathode materials designed with anions can break the energy density ceiling, resulting in batteries that are more sustainable and less expensive.
However, storage efficiency still needs improvement. Currently, not all of the electricity stored in the battery during charging is available for use upon discharge. Once these improvements are made, the result will be a battery that outperforms current models in terms of cost, efficiency, and environmental impact.
