Deciphering Intricacies in Directional CO 2 Conversion From Electrolysis to CO 2 Batteries

ABSTRACT Renewable electricity storage coupled with CO 2 conversion (power‐to‐X) has emerged as a fantastic means for reconciling energy demand and CO 2 mitigation issues. To successfully implement such approaches, directional CO 2 conversion is a crucial prerequisite, making it a pivotal research area. Thereinto, direct electrolysis of CO 2 (power‐to‐chemicals), while far from being commercially successful, has achieved substantial progress in selectivity and conversion rate for certain chemicals. Metal–CO 2 (M‐CO 2 ) batteries can integrate several energy conversion pathways (power‐to‐metal paired with metal‐to‐power and/or metal‐to‐chemicals); however, their progress remains limited, particularly for directional generation of valuable chemicals. Meanwhile, the lack of understanding and benchmarking across materials and performances hinders rational evaluation and technology advancement of M‐CO 2 batteries. Herein, we explore the critical elements required to achieve directional CO 2 conversion in M‐CO 2 battery by comparing with direct electrocatalytic CO 2 reduction technology, building from fundamental chemistry concepts and issues, basis of materials design and product selectivity, to device‐level considerations that facilitate high practical energy and power density, as well as long‐duration conversion and storage. The emphasis lies on how to rationally design a precise catalyst and configuration for M‐CO 2 batteries, with the expectation that forward‐looking insights will inspire top‐notch investigations and engage various sectors of society.