High surface-area cathodes for aluminum ion batteries

Abstract

Lithium ion batteries (LIBs) are highly efficient. They have high capacities and long cycle lives with coulombic efficiencies of over 98%. With their immense success, they now find use in many applications, for example, electric vehicles (EVs). The increasing demand puts a lot of pressure on lithium and cobalt reserves as these metal oxides (LiCoO2) form the basic component of LIB electrode. Furthermore, the typical electrolyte in LIBs is flammable rendering these batteries hazardous. Any damage to the cell (like thermal runaway reactions, direct electrode contact) leads to short circuits, sometimes leading to an explosion! Aluminum ion batteries (AIBs) are cheap and non-flammable alternatives to LIBs. They can be easily recycled. The theoretical energy density of aluminum is higher than lithium and hence, it may exceed the current performance of LIBs. Graphite is the most commonly used cathode in AIBs. Its layered structure helps in insertion/extraction of electrolyte ions (AlxCly) or Al3+ into the cathode. However, most of the AIBs have a low electrode potential and a short cycle life. We will present new high-surface area cathode nanomaterials that will lead to better performing AIBs. Some of the tested cathodes have shown an improved cycle life and a much better electrode potential (~2.0 V).