High-performance aluminum-polyaniline battery based on the interaction between aluminum ion and -NH groups

Aluminum-ion batteries (AIBs) are a type of promising energy storage device due to their high capacity, high charge transfer efficiency, low cost, and high safety. However, the most investigated graphitic and metal dichalcogenide cathodes normally possess only a moderate capacity and a relatively low cycling stability, respectively, which limit the further development of high-performance AIBs. Here, based on the results of first principles calculations, we developed a polyaniline/graphene oxide composite that exhibited outstanding performances as a cathode material in AIBs (delivering 180 mA h g− after 4000 cycles), considering both the discharge capacity and the cycling performance. Ex-situ characterizations verified that the charge storage mechanism of polyaniline depended on the moderate interactions between −NH in the polyaniline chain and the electrolyte anions, such as AlCl4−. These findings lay the foundation of the development of high-performance AIBs based on conducting polymers.