Gradient Design for High‐Energy and High‐Power Batteries

Abstract Charge transport is a key process that dominates battery performance, and the microstructures of the cathode, anode, and electrolyte play a central role in guiding ion and/or electron transport inside the battery. Rational design of key battery components with varying microstructure along the charge‐transport direction to realize optimal local charge‐transport dynamics can compensate for reaction polarization, which accelerates electrochemical reaction kinetics. Here, the principles of charge‐transport mechanisms and their decisive role in battery performance are presented, followed by a discussion of the correlation between charge‐transport regulation and battery microstructure design. The design strategies of the gradient cathodes, lithium‐metal anodes, and solid‐state electrolytes are summarized. Future directions and perspectives of gradient design are provided at the end to enable practically accessible high‐energy and high‐power‐density batteries.