Review of Current Collector-, Binder-, Conductive Additive-Free, and Freestanding Electrodes in Lithium and Related Batteries

Because current collectors (CCs), Binders (BDs), and conductive additives (CAs) in cathodes and anodes do not directly contribute to charging and discharging, they decrease the energy density of the battery. Improvement of battery energy density is essential for future batteries. If it were possible to pack electrode active materials into the empty space without using CCs, BDs, and CAs, the energy density of the battery would increase. Therefore, attempts to avoid using these materials in batteries are being investigated. In this review article, methods for manufacturing electrodes without using these materials, as well as the performance and durability of the electrodes, are summarized and discussed. After explaining the function and necessity of the CCs, BDs, and CAs, methods for manufacturing electrodes without using CCs, BDs, and CAs, as well as the performance and durability of the electrodes, were summarized and discussed. In addition to battery performance, the mechanical durability of the electrodes is also explained since not using CCs, BDs, and CAs will cause problems with the electrodes’ mechanical durability.