This review focuses on the application of process engineering in electrochemical energy conversion and storage devices innovation. For polymer electrolyte based devices

it highlights that a strategic simple switch fromproton exchange membranes (PEMs) to hydroxide exchange membranes (HEMs) may lead to a new-generation of affordable electrochemical energy devices including fuel cells

electrolyzers

and solar hydrogen generators. For lithium-ion batteries

a series of advancements in design and chemistry are required for electric vehicle and energy storage applications. Manufacturing process development and optimization of the LiFePO

4

/C cathodematerials and several emerging novel anode materials are also discussed using the authors' work as examples. Design and manufacturing process of lithium-ion battery electrodes are introduced in detail

and modeling and optimization of large-scale lithium-ion batteries are also presented. Electrochemical energy materials and device innovations can be further prompted by better understanding of the fundamental transport phenomena involved in unit operations.