Battery-Type Lithium-Ion Hybrid Capacitors: Current Status and Future Perspectives

The lithium-ion battery (LIB) has become the most widely used electrochemical energy storage device due to the advantage of high energy density. However, because of the low rate of Faradaic process to transfer lithium ions (Li+), the LIB has the defects of poor power performance and cycle performance, which can be improved by adding capacitor material to the cathode, and the resulting hybrid device is also known as a lithium-ion battery capacitor (LIBC). This review introduces the typical structure and working principle of an LIBC, and it summarizes the recent research developments in advanced LIBCs. An overview of non-lithiated and pre-lithiated anode materials for LIBCs applications is given, and the commonly used pre-lithiation methods for the anodes of LIBCs are present. Capacitor materials added to the cathodes, and suitable separator materials of LIBCs are also reviewed. In addition, the polarization phenomenon, pulsed performance and safety issues of LIBCs and electrode engineering for improving electrochemical performance are systematically analyzed. Finally, the future research and development direction of advanced LIBCs is prospected through the discussion of the existing problems of an LIBC in which the battery material in the composite cathode is LiNixCoyMn1-x-yO2 (NCM).

Automated summary

The lithium-ion battery (LIB) is widely used as an electrochemical energy storage device due to its high energy density. However, it suffers from poor power performance and cycle performance. These issues can be addressed by incorporating capacitor material into the cathode, resulting in a lithium-ion battery capacitor (LIBC). This review presents the typical structure and working principle of LIBCs and summarizes recent advancements in this field, including non-lithiated and pre-lithiated anode materials, pre-lithiation methods, capacitor materials, suitable separator materials, and electrode engineering for improved electrochemical performance. Future research directions for advanced LIBCs are also discussed based on the existing problems.