Xin-Bing Cheng

Lithium (Li) metal batteries have emerged as one of the most promising candidates for next‐generation energy storage systems due to the potentially high energy density. Nevertheless, repeated interfacial breakdown causes a short lifespan and poor safety. Inspired by the role of plant root systems in anchoring soil, an oligomer‐anchored LiZn nanocrystal composite interphase is constructed on the Li metal anode via a simple spray‐coating strategy, simultaneously enhancing the electrochemical stability and thermal safety of Li metal batteries. The LiZn alloy in the composite interphase restructures the interface energy distribution and reduces the local current density, thereby facilitating uniform lateral Li deposition. The oligomer serves as a binder to glue LiZn particles together and preserve the structural integrity of the interphase. A Li||LiNi _0.5 Co _0.2 Mn _0.3 O ₂ coin cell with the composite interphase exhibits a lifespan of 700 cycles at 1 C with a high cathode loading of 3.06 mAh cm ⁻² . The 1.38 Ah Li||LiNi _0.8 Co _0.1 Mn _0.1 O ₂ pouch cell achieves a capacity retention of 86% after 200 cycles. When the cycled pouch cells undergo forced thermal runaway, the composite interphase elevates the trigger temperature from 124°C to 191°C. This interphase design provides novel insights to enhance the service lifespan and thermal safety of high energy density batteries.

In situ gel polymer electrolytes (GPEs), which confine liquid electrolytes within a polymer matrix, are promising for realizing high‐safety lithium (Li) metal batteries. However, the liquid phase and the polymer matrix act as reciprocal chokes: the liquid expedites ion transport but plasticizes the matrix and compromises its mechanical strength, whereas the matrix provides rigidity yet obstructs ionic conduction. In this study, we propose a molecular scaffold strap strategy that decouples the regulation of mechanical robustness and ion transport in GPEs. Specifically, six‐arm monomers are employed to form a 3D polymer matrix, while ethylene glycol dibutyl ether, with a size‐matched anchoring character, acts as a scaffold strap that strengthens adjacent polymer segments. Fluorinated carbonate cosolvents further facilitate Li ⁺ transport and interfacial stability. The engineered GPE exhibits a high modulus of 8.9 MPa, ionic conductivity of 3.82 × 10 ⁻⁴ S cm ⁻¹ , Li ⁺ transference number of 0.68, and stable electrode interfaces. The Li||LiNi _0.8 Co _0.1 Mn _0.1 O ₂ pouch cell (2.7 Ah) achieves 87% capacity retention after 100 cycles and exhibits an elevated self‐heating onset temperature of 160.7°C. Furthermore, a high energy density of 506 Wh kg ⁻¹ is demonstrated in the Cu||LiNi _0.92 Co _0.03 Mn _0.05 O ₂ pouch cell (3.5 Ah).

In situ gel polymer electrolytes (GPEs), which confine liquid electrolytes within a polymer matrix, are promising for realizing high‐safety lithium (Li) metal batteries. However, the liquid phase and the polymer matrix act as reciprocal chokes: the liquid expedites ion transport but plasticizes the matrix and compromises its mechanical strength, whereas the matrix provides rigidity yet obstructs ionic conduction. In this study, we propose a molecular scaffold strap strategy that decouples the regulation of mechanical robustness and ion transport in GPEs. Specifically, six‐arm monomers are employed to form a 3D polymer matrix, while ethylene glycol dibutyl ether, with a size‐matched anchoring character, acts as a scaffold strap that strengthens adjacent polymer segments. Fluorinated carbonate cosolvents further facilitate Li ⁺ transport and interfacial stability. The engineered GPE exhibits a high modulus of 8.9 MPa, ionic conductivity of 3.82 × 10 ⁻⁴ S cm ⁻¹ , Li ⁺ transference number of 0.68, and stable electrode interfaces. The Li||LiNi _0.8 Co _0.1 Mn _0.1 O ₂ pouch cell (2.7 Ah) achieves 87% capacity retention after 100 cycles and exhibits an elevated self‐heating onset temperature of 160.7°C. Furthermore, a high energy density of 506 Wh kg ⁻¹ is demonstrated in the Cu||LiNi _0.92 Co _0.03 Mn _0.05 O ₂ pouch cell (3.5 Ah).

Graphite (Gr) lithiation is fundamentally an electron‐driven process, where the temporal disparity between femtosecond‐scale (10 ⁻¹⁵ s) interfacial electron transfer (IET) and picosecond‐to‐nanosecond (10 ⁻¹² ∼ 10 ⁻⁹ s) ion migration dictates a non‐concerted kinetic response. Since electrons respond instantaneously to potential while solvated lithium (Li) remains momentarily stationary, this transient IET acts as a critical upstream “kinetic regulator” by pre‐polarizing the interface, which in turn lowers the activation barrier for the subsequent rate‐determining Li ⁺ desolvation step. However, this foundational precursor is frequently overlooked. Compared with neutral solvents, anions possess higher charge density and frontier orbital levels, offering a superior propensity for electron transfer. In this work, we reveal that modulating anion participation in the solvation sheath can purposely tailor the Gr surface toward an electron‐rich state, which effectively weakens Li ⁺ –solvent interactions and lowers the activation barrier of Li de‐coordination. To quantify this effect, we propose the “apparent electron transfer propensity” (AETP) descriptor to bridge microscopic solvation speciation with macroscopic kinetics. This finding also elucidates why anion‑rich Li solvates or anions with high electron density delocalization (such as FSI ⁻ ) can deliver superior battery rate capability. This work establishes IET as a discrete physical criterion for deciphering kinetic bottlenecks and designing high‐power battery interfaces.

Graphite (Gr) lithiation is fundamentally an electron‐driven process, where the temporal disparity between femtosecond‐scale (10 ⁻¹⁵ s) interfacial electron transfer (IET) and picosecond‐to‐nanosecond (10 ⁻¹² ∼ 10 ⁻⁹ s) ion migration dictates a non‐concerted kinetic response. Since electrons respond instantaneously to potential while solvated lithium (Li) remains momentarily stationary, this transient IET acts as a critical upstream “kinetic regulator” by pre‐polarizing the interface, which in turn lowers the activation barrier for the subsequent rate‐determining Li ⁺ desolvation step. However, this foundational precursor is frequently overlooked. Compared with neutral solvents, anions possess higher charge density and frontier orbital levels, offering a superior propensity for electron transfer. In this work, we reveal that modulating anion participation in the solvation sheath can purposely tailor the Gr surface toward an electron‐rich state, which effectively weakens Li ⁺ –solvent interactions and lowers the activation barrier of Li de‐coordination. To quantify this effect, we propose the “apparent electron transfer propensity” (AETP) descriptor to bridge microscopic solvation speciation with macroscopic kinetics. This finding also elucidates why anion‑rich Li solvates or anions with high electron density delocalization (such as FSI ⁻ ) can deliver superior battery rate capability. This work establishes IET as a discrete physical criterion for deciphering kinetic bottlenecks and designing high‐power battery interfaces.

Ion dynamics in carbonate electrolytes are fundamentally governed by the solvation power of cyclic solvents, a property whose quantification remains elusive because of the intricate competition between electronic and steric effects. We decouple these influences by defining two core descriptors: (i) the nature of the functional groups furnishing solvation sites, encompassing coordinating atom charges and electron localization function (ELF) values, and (ii) structural adaptability, derived from the substituent volume and its distance from the coordination site. Building upon this framework, the quantitative correlations between these descriptors and solvation power, along with their underlying mechanisms, are investigated through an integrated approach of mathematical fitting and machine learning (ML). Notably, functional group properties and structural compatibility comparably contribute to solvation power, challenging the conventional understanding that functional group attributes predominantly dictate the solvation behavior. This work provides a chemical foundation for the rational selection of cyclic carbonate-based electrolytes for battery chemistry.

Constructing high-energy batteries through three structural design strategies of LMAs using pure Li, alloys and composite structures.