Interface Engineering

All-solid-state lithium metal batteries (ASSBs) promise higher energy density and improved safety, but their progress is limited by lithium dendrite growth, interfacial decomposition, and structural instability at the anode.

Our group addresses these challenges by introducing a nanoporous Li₄Ti₅O₁₂ (LTO) oxide interlayer as a robust protective shield. The LTO framework maintains structural integrity while providing efficient ionic and electronic pathways, enabling uniform and dense lithium plating/stripping without void formation or electrolyte degradation.

With this design, full cells achieve stable cycling for over 300–400 cycles at high current densities and practical areal capacities, surpassing conventional alloy-based interlayers. This work highlights a new strategy to regulate lithium growth and establish durable, high-performance ASSBs, bridging fundamental interfacial science with practical device engineering.

Dayoung Jun‡, Seong Gyu Lee‡, Ji Eun Jung, Kyu Seok Kim, Haena Yim, Hyuksoo Shin, Jungho Lee, Yun Jung Lee*, Oxide-based Nanoporous Interlayer for Durable Anodic Interface in All-Solid-State Lithium Metal Batteries, ACS Energy Letters, 9, 3475-3483, 2024 

All-solid-state lithium-ion batteries (ASSLBs) are promising for safe, high-energy storage, but they face severe issues of interfacial instability between electrode and solid electrolyte, which leads to side reactions and rapid capacity fading.

In this study, our group proposed a sacrificial cathode strategy: by introducing a specially designed sacrificial component in the cathode, the material preferentially reacts with unstable interfacial species. This approach effectively “cleans” the electrode–electrolyte interface, suppressing parasitic reactions and stabilizing long-term operation.

As a result, cells employing the sacrificial cathode exhibited significantly improved cycling stability and capacity retention, compared to conventional cathode designs. This work demonstrates that sacrificial electrode engineering can be a powerful tool to overcome interfacial degradation and guide the development of durable all-solid-state lithium-ion batteries.

Dayoung Jun‡, Kyu Seok Kim‡, Tae Eun Kim, Seihyun Shim, Seong Gyu Lee, Ji Eun Jung, Ji Young Kim, Ki Yoon Bae, Samick Son, Yun Jung Lee*, Strategic Cathode Configuration for Incorporating Sacrificial Materials in All-Solid-State Batteries: Mixed vs. Separate Layer, Energy Storage Materials, 78, 104258, 2025