Electrodeposition of Li-Ion Cathode Materials: The Fascinating Alternative for Li-Ion Micro-Batteries Fabrication

Li-ion microbatteries are the frontline candidates to fulfill the requirements of powering miniature autonomous devices. However, it still remains challenging to attain the required energy densities of > 0.3mWh cm−2 μm−1 in a planar configuration. To overcome this limitation, 3D architectures of LIMBs have been proposed. However, most deposition techniques are poorly compatible with 3D architectures because they limit the choice of current collectors and selective deposition of the active materials. Electrodeposition was suggested as an alternative for rapidly and reproducibly depositing active materials under mild conditions, and with controlled properties. However, despite the huge potential, electrodeposition remains underexplored for LIMB cathode materials, partly due to challenges associated with the electrodeposition of Li-ion phases. Herein, we review advances in the electrodeposition of Li-ion cathode materials with the main focus set on the direct, one-step deposition of electrochemically active phases. We highlight the merits of electrodeposition over other methods and discuss the various classes of reported materials, including layered transition metal oxides, vanadates, spinel, and olivines. We offer a perspective on the future advances for the adoption of electrodeposition processes for the fabrication of microbatteries to pave the way for future research on the electrodeposition of cathode materials.