Architecture Engineering for Thick Electrodes in High-Energy Batteries: Challenges and Strategies

With the burgeoning demand for smart portable electronic devices and high-performance electric vehicles, there is tremendous urgency to further dramatically improve the energy density of rechargeable batteries. Although utilizing thick electrodes to improve energy density is a straightforward and productive approach, the slow reaction kinetics and inadequate mechanical strength caused by the thickness increase have hampered their development. Therefore, to break through the bottleneck of thick electrodes, we comprehensively summarize the recent progress of thick electrode architecture engineering in the field of rechargeable batteries. Considering the relationship between electrode structure and electrochemical performance, we focus on the four crucial challenges (high tortuosity, slow electron and ion transport, improper porosity, and visible cracking) and corresponding solutions (constructing vertically aligned hierarchical channels, introducing multidimensional conductive materials, regulating the degree of calendering, and so on) in constructing thick electrodes. Finally, the construction strategy of thick electrodes and the inextricable relationship of these crucial factors are summarized, and an outlook on the development and research directions toward thick electrodes is discussed, providing valuable reference for designing high-performance thick electrodes.