Yu Liu

NASICON polyanionic cathodes are widely studied because they combine structural stability, low cost, and superior rate capability for sodium‐ion batteries (SIBs). However, local lattice strain and sluggish multielectron redox kinetics during deep (de)sodiation limit the energy density and lifespan of NASICON cathodes. Here, we regulate Na1 sites with potassium in the multimetal NASICON cathode Na ₃ K _0.6 V _1.4 Mn _0.3 Fe _0.3 (PO ₄ ) ₃ (NKVMFP). Calculations and experiments indicate that K occupation at Na1 sites regulates the alkali ion environment, which in turn modifies the MnO ₆ crystal field, improves Mn/V redox utilization, and suppresses Na ⁺ /vacancy ordering. NKVMFP delivers an energy density of 381 Wh kg ⁻¹ , sustains 12,000 cycles at 4 A g ⁻¹ , and shows a volume variation of 4.13%; its stable operation in a 320 mAh pouch cell further supports its practical potential. These results show that Na1 site alkali ion regulation can improve redox utilization and structural reversibility in multimetal NASICON cathodes.

Sodium‐ion batteries are promising for sustainable energy storage, but their energy density still lags behind lithium‐ion systems. Na ₃ V ₂ (PO ₄ ) ₂ F ₃ (NVPF) is an attractive high‐voltage polyanionic cathode, but fluorine loss generates low‐voltage Na ₃ V ₂ (PO ₄ ) ₃ impurities that lower energy density and aggravate lattice deformation during cycling. Here, we report a multielement V‐site charge modulation strategy, realized in Na _3‐δ V _1.9 Zr _0.02 Ti _0.02 Cr _0.02 Fe _0.02 Al _0.02 (PO ₄ ) ₂ F ₃ (ME‐NVPF). The deliberate combination of high‐valence Zr ⁴⁺ , Ti ⁴⁺ , and same‐valence Cr ³⁺ , Fe ³⁺ , Al ³⁺ cations creates a heterogeneous M–O/F bonding network with multi‐directional electrostatic interactions enhancing lattice‐F retention that completely eliminates NVP impurities, lowers the Na ⁺ migration barrier, and reduces unit‐cell volume variation to merely 2.87%. Consequently, ME‐NVPF delivers a record‐high energy density of 477 Wh kg ⁻¹ , sustains 11 000 cycles, operates across −40 to 80°C, and is further validated in 600 mAh‐level pouch cells. This work establishes multielement compositional regulation as an effective strategy for designing high‐energy, long‐life, and all‐temperature polyanionic cathodes.

Aqueous zinc metal batteries (AZMBs) face persistent challenges from interfacial instability including dendrite growth and side reactions, yet a critical obstacle lies in the mismatch between anode‐side assessments and actual full‐cell cycling performance. Through explainable machine learning analysis, this study introduces a physically motivated Metal Anode/Electrolyte Interphase Descriptor (MAEID) that unifies three critical parameters, including transference number, relative exchange current density, and elastic modulus, into one predictive metric. Within the present dataset, standalone leave‐one‐out cross‐validation (LOOCV) analysis shows that MAEID provides stronger predictive capability than individual single‐parameter descriptors for full‐cell capacity retention. Guided by this descriptor, a soft solid electrolyte interphase (SSEI) based on a polyacrylic acid complex was designed, achieving a high Zn ²⁺ transference number of 0.84 with low elastic modulus of 4.1 MPa, and suitable exchange current density. When evaluated under practical anode‐free conditions, the SSEI‐enabled cell sustained over 1800 stable cycles without capacity decay. This work establishes a data‐driven paradigm shifting from empirical single‐parameter optimization to rational multi‐parameter synergy, offering a generalizable framework for designing high‐performance interphases in metal battery systems.

Ligand design is crucial for enhancing all‐iron flow batteries’ (AIFB) electrochemical performance. This work proposes design principles of ligands for AIFB based on coordination chemistry theory, and designs a class of ethylenediamine derivative ligands. These principles integrate three key functions: (1) regulation of Fe ^II /Fe ^III potential through coordination functional groups, (2) enhancement of iron‐complex solubility via hydrophilic modification and molecular asymmetry design, (3) improvement of cycling stability through hexadentate chelation and size exclusion effect. Herein, N,N′‐dimethyl‐N,N′‐(2‐(2′‐pyridyl)‐6‐pyridylmethyl) ethylenediamine (EDMB) and N,N′‐di(2‐hydroxybenzyl) ethylenediamine‐N,N′‐diacetic Acid (HBED) are designed as catholyte and anolyte ligands of AIFB. An AIFB with a voltage of 1.32 V is designed, which can cycle stably for 13 000 times. To further enhance the battery's energy density, a more hydrophilic anolyte ligand, SHBED, is designed. Ultimately, the solubilities of Fe–EDMB and Fe–SHBED reach 1.85 and 1.97 mol L ⁻¹ , respectively. The AIFB can cycle normally with catholyte and anolyte concentrations of 1.5 and 1.25 mol L ⁻¹ . It shows record specific capacity and energy density of 18.27 Ah L ⁻¹ and 21.01 Wh L ⁻¹ , almost doubled compared to the currently reported highest energy density of AIFB. Although this design principle is only validated on ethylenediamine derivative ligands, its underlying logic can be extended to other iron‐based ligands.

Although metastable 1T‐MoS ₂ boasts advantages such as high electrical conductivity, rapid ion diffusion, and high capacity, its thermodynamic instability and stringent synthesis conditions impede practical applications. Addressing the core of phase regulation in MoS _2— the electronic states of the Mo 4d orbitals—a synergistic electron modulation strategy utilizing Cu ²⁺ / cations and anions was employed to successfully anchor highly stable 1T‐MoS ₂ (CP‐MoS ₂ @rGO) onto a reduced graphene oxide (rGO) substrate. The Cu ²⁺ / ions induce a charge redistribution that drives the reorganization of Mo 4d orbitals. Concurrently, the interlayer intercalation support effect of expands the interlayer spacing, which effectively suppresses topological phase transitions during the sodiation/desodiation process, thereby achieving kinetic stabilization of the metastable 1T phase. Benefiting from this unique structural design, the CP‐MoS ₂ @rGO exhibits exceptional rate capability (372.5 mAh g ⁻¹ at 24 A g ⁻¹ ) and an ultra‐long cycle life (stable cycling for over 8000 cycles at a current density of 18 A g ⁻¹ ), along with highly reversible structural reconstruction. This work establishes a new paradigm for the rational design and stabilization of metastable 1T‐MoS ₂ ‐based materials for advanced energy storage applications.

The transient intermediate phase Na _x Cu _y S _z formed during the sodiation of copper sulfide anodes has recently been recognized as a key species governing fast ion/electron transport and exceptional structural resilience in sodium‐ion batteries. However, its direct synthesis remains elusive due to intrinsic kinetic instability. Herein, we unveil that the kinetic instability of this class of phases arises from the calculation of phonon dispersion, explaining the failure of conventional solid‐state routes. Furthermore, we establish a rational design framework based on lattice compatibility and anion‐binding energy deviation, followed by systematic phonon spectrum calculations to screen not only the dopant element but also the optimal doping concentration, stabilizing the thermodynamics and suppress kinetic instabilities. Guided by this principle, we achieve the first successful solid‐state synthesis of a long‐sought intermediate phase, NaCu _1.5 Co _0.5 S ₂ . NaCu _1.5 Co _0.5 S ₂ exhibits outstanding rate capability (337.9 mAh g ^{− 1} at 50 C) with a high capacity of 589.9 mAh g ^{− 1} at 0.1 C and robust cycling stability (>5000 cycles at 30 C). Our study not only realizes the targeted synthesis of a critical but previously inaccessible phase but also provides a generalizable design paradigm for stabilizing metastable functional materials, opening new avenues for next‐generation fast‐charging battery chemistries.

Aqueous zinc metal batteries (AZMBs) employing halogen‐ or manganese‐based cathodes and anode‐free design possess the highest energy density among the aqueous battery families. However, their performance is severely limited by interfacial side reactions and anode‐cathode cross‐talk, which undermine energy density and cycle life. Conventional strategies focusing on a single interface are inadequate to address these systemic issues. The optimal strategy cluster from literature data mining guided the material system creation via a data‐driven process of molecular descriptor screening. This guided the creation of an asymmetric dual‐interphase separator, featuring a Zn ²⁺ ‐supplying interphase (ZSI) on the anode side that suppresses polyhalide shuttling and accelerates desolvation, and a composite conductive interphase (CCI) on the cathode side that enhances multi‐electron reaction kinetics and active species utilization. Enabled by the asymmetric dual‐interphase engineering, the constructed anode‐free Zn||MnO ₂ full cell achieves a high voltage efficiency of 90% and stable cycling over 1000 cycles. Concurrently, a state‐of‐the‐art anode‐free Zn||I ₂ battery delivers an energy efficiency exceeding 90% at high areal loading of 38.14 mg cm ⁻² . Furthermore, a universal zinc metal anode/electrolyte interphase descriptor (ZMAEID) was proposed, mechanistically linking interfacial electrochemical behavior with mechanical stability. This systematic, data‐driven, and theory‐guided strategy establishes a new paradigm for next‐generation anode‐free AZMBs.

Aqueous zinc metal batteries (AZMBs) employing halogen‐ or manganese‐based cathodes and anode‐free design possess the highest energy density among the aqueous battery families. However, their performance is severely limited by interfacial side reactions and anode‐cathode cross‐talk, which undermine energy density and cycle life. Conventional strategies focusing on a single interface are inadequate to address these systemic issues. The optimal strategy cluster from literature data mining guided the material system creation via a data‐driven process of molecular descriptor screening. This guided the creation of an asymmetric dual‐interphase separator, featuring a Zn ²⁺ ‐supplying interphase (ZSI) on the anode side that suppresses polyhalide shuttling and accelerates desolvation, and a composite conductive interphase (CCI) on the cathode side that enhances multi‐electron reaction kinetics and active species utilization. Enabled by the asymmetric dual‐interphase engineering, the constructed anode‐free Zn||MnO ₂ full cell achieves a high voltage efficiency of 90% and stable cycling over 1000 cycles. Concurrently, a state‐of‐the‐art anode‐free Zn||I ₂ battery delivers an energy efficiency exceeding 90% at high areal loading of 38.14 mg cm ⁻² . Furthermore, a universal zinc metal anode/electrolyte interphase descriptor (ZMAEID) was proposed, mechanistically linking interfacial electrochemical behavior with mechanical stability. This systematic, data‐driven, and theory‐guided strategy establishes a new paradigm for next‐generation anode‐free AZMBs.

The applicability and long‐term stability of all‐solid‐state Na‐ion batteries (ASSNIBs) depend on maintaining a robust ionic transport interface between electrolytes and electrodes. However, most sodium‐ion solid‐state electrolytes (SSEs) exhibit insufficient ionic conductivity and rigid particle contacts. In this work, a binary amorphous SSE was designed by incorporating high‐polarizability and low‐electronegativity S ²⁻ anions into halide SSEs, featuring mixed S/Cl anionic framework and enhanced flexibility and reorientation dynamics of the anion sublattice, rendering the SSEs both high ionic conductivity (up to 2.12 mS cm ⁻¹ at 30°C) and excellent formability (reduction of 63.3% of the Young's modulus to 2.2 GPa and 46% of the hardness to 2.02 GPa). Multi‐scale characterizations and theoretical calculations reveal that the unique S/Cl mixed‐anion framework promotes the structural amorphization and microscopically optimizes the sodium‐ion potential energy landscape by modulating the Na ⁺ coordination environment through local polyhedral distortion. Furthermore, the assembled ASSNIBs maintain c.a . 100% coulombic efficiency over long‐term cycling, with a capacity retention of 91% after 270 cycles at 0.2C and 80% for more than 1400 cycles at 1C. Therefore, these findings provide new insights for the development of high‐performance binary SSEs for ASSNIBs and general rules for the design of other ionic SSEs.