The Latent Culprit of Anode‐Free Lithium Metal Batteries Degradation

Abstract Anode‐free lithium metal batteries (AFLMBs), which eliminate excess lithium by pairing a bare current collector with a fully lithiated cathode, promise unprecedented energy density, cost efficiency, and safety. However, their practical viability is plagued by rapid capacity fade, primarily driven by lithium loss from inactive Li formation and electrolyte depletion. Crucially, the complex interfacial dynamics and evolution unique to AFLMBs, including current collector/electrolyte, Li deposit/current collector, and Li deposit/electrolyte, collectively amplify degradation mechanisms. These intricate interface networks render conventional lithium metal battery strategies largely ineffective. This review starts from deciphering the complex interplay between multiple interfaces, highlighting the critical role of limited lithium source in accelerating failure. To follow, compensatory and countermeasure strategies are summarized to provide a clear connection between failure pathway and targeted solutions, offering comprehensive roadmap for AFLMBs optimization. Insights on future development are also provided in this review.