Anode-less lithium metal batteries (LMBs) are attractive for high energy density and low manufacturing cost, yet their cycle life is severely hindered by active Li loss arising from unstable deposition. Here, a lithiophilic antimony (Sb) layer is in situ constructed on a commercial copper (Cu) current collector through a scalable and tunable chemical plating strategy. The Sb-plated Cu current collector (Sb@Cu) features balanced Li adsorption thermodynamics and surface migration kinetics: strong adsorption promotes uniform nucleation, while low migration barrier facilitates Li redistribution for homogeneous growth. Consequently, the nucleation overpotential is markedly reduced to 10 mV at 1 mA cm−2, inducing dense and dendrite-free Li deposition. The Li||Sb@Cu asymmetric cell delivers over 700 cycles at 1 mA cm−2 with 99.2% average Coulombic efficiency. When paired with LiFePO4, the anode-less full cell retains 86.4% of its initial capacity after 850 cycles at 2 C. More importantly, the scaled-up pouch cell also exhibits stable cycling for over 300 cycles under an ultra-low N/P ratio of 0.9. This work not only provides a scalable approach to producing advanced Cu current collectors for durable anode-less LMBs, but also offers new insight for lithiophilic interface design by balancing Li adsorption and migration.

Self-assembled molecule (SAM) layers have significantly enhanced the efficiency of inverted perovskite solar cells (PSCs). However, SAM aggregation leads to non-uniform interfacial contact, limiting further improvements in efficiency and stability. Here we employ perfluoro-2-propoxypropanoic acid (PFA) to construct a molecular confinement structure on the surface of the NiOx substrate. This confinement structure enables uniform embedding of SAMs within the PFA sub-monolayer and prevents their vertical stacking. Together, PFA and SAM form a complete interlayer that enhances the interface contact and reduces defects between NiOx and perovskite. Moreover, PFA molecules in the confinement structure interact with the buried perovskite interface via hydrogen bonding and dipolar interaction, further stabilizing the structure. These enhancements enable PSCs to achieve an efficiency of 26.84% (certified value of 26.79%) with a high fill factor of 86.61%. And the device exhibits excellent operational stability, retaining 94.6% of its initial efficiency after 800 hours of 1-sun maximum power point tracking under the ISOS-L-1 protocol.

The instability of metallic lithium anodes is the biggest challenge in developing high-energy lithium metal batteries (LMBs). Herein we develop a topologization strategy to stabilize metallic lithium anode through coupled thermodynamic-kinetic regulation. An optimized sinusoidal-like topological interface is identified based on systematic screening of various topological structures, where lithium deposition is dictated by the competition between thermodynamic and kinetic factors. Specifically, the thermodynamic analysis confirms preferential lithium electrodeposition in valley region driven by surface energy gradient, while kinetic barriers arising from sluggish ion transfer force lithium electrodeposition to deviate toward peak region. By achieving a delicate balance between thermodynamic driving forces and kinetic constraints with adjusting sine parameters, the sinusoidal-like lithium (marked as Sin-Li) anode exhibits excellent long cycling stability for over 2800 h at 1 mA cm- 2/1 mAh cm- 2 and up to 900 h at high current density/capacity of 10 mA cm- 2/10 mAh cm- 2. When paired with a LiFePO4 (LFP) cathode, the full cell achieves ultra-long cycle life exceeding 5700 cycles at 2C, with a capacity decay rate of only 0.008 % per cycle. Moreover, the scaled-up Sin-Li||LFP pouch cell also exhibits excellent cycling stability even under practically harsh conditions. This work not only elucidates the coupled thermodynamic-kinetic regulation mechanism of surface topology on Li electrodeposition process, but also offering a feasible and effective strategy for optimizing LMBs toward practical applications.

To accommodate the burgeoning demand for high energy density of lithium-ion batteries, the advancement of ultra-high nickel cathodes has become an urgent imperative. Nevertheless, these cathode materials inherently suffer from rapid capacity decay and inferior structural stability as the nickel content increases. Critical bottlenecks, including severe mechanical strain and irreversible phase transitions, still pose formidable challenges. Herein, we propose a strategic Al and Er dual-doping approach to modify the LiNi0.96Co0.04O2 ultra-high nickel cathode. The fundamental mechanism stems from the strong oxygen affinity of the dual dopants, contributing to enhanced lattice framework stability. Al ions stabilize the transition-metal–oxygen framework, while Er ions regulate the local lattice environment and facilitate Li-ion transport. Through this cooperative effect, the Li-ion transport pathways are optimized, which concomitantly diminishes electrochemical polarization and impedance. Consequently, the cathode prepared under the optimized nominal Al/Er dual-doping condition delivers exemplary cycling stability. Under a high cutoff voltage of 4.4 V, it retains 65.33% of its initial capacity after 300 cycles, significantly outperforming the 48.79% retention of the pristine counterpart. This work verifies the feasibility of the Al/Er dual-doping strategy and provides novel theoretical and experimental insights for the design of robust cathode materials tailored for lithium-ion batteries with high energy density.

In situ polymerized solid-state electrolytes for lithium-metal batteries suffer from the inherent conflict between robust polymer network and delicate Li+ transportation coordination structure. Here, we demonstrate a multiscale engineering strategy through the in situ construction of a solid-state "Solvated-Ionic-Liquid in Oligomer" electrolyte to address this trade-off. Critically, the poly(vinyl carbonate) (PVC) oligomer network is designed to preserve 86.8% of the [Li(Tetraglyme)]+ solvation structure of solvated ionic liquid (SIL), which enables high conductivity and a wide electrochemical window. This oligomer framework functions as a molecular-scale anion trap, collaboratively working with a nanoscale fluoroethylene carbonate (FEC)-derived LiF-rich solid electrolyte interphase and a macroscale alumina fiber scaffold for improving Li+ transportation and mechanical robustness. This triple-component synergy unlocks a high Li+ transference number (0.465) and a remarkable ionic conductivity (4.32 mS cm-1), enabling a stable lithium-metal interface (700 h in Li/Li symmetric cells) and exceptional cycling durability in Li/LiFePO4 batteries (79.7% capacity retention after 1000 cycles at 3 C).

Ultra-high nickel layered oxides are currently among the mainstream cathode materials for lithium-ion batteries(LIBs),having garnered extensive research and rapid development due to their high capacity.This review article defines ultra-high nickel oxides with a nickel content of ≥0.9 among transition metal components and proceeds based on this definition.Although high-nickel oxide cathode materials have undergone decades of development,the pursuit of increased capacity in ultra-high nickel oxides inevitably leads to compromised capacity retention,thermal stability,and unavoidable structural degradation,thereby hindering their progression.The review article focuses on summarizing the main challenges currently faced by ultra-high nickel oxides as cathode materials for lithium-ion batteries and as well as the mainstream modification measures.Finally,it is pointed out that the future research on ultra-high nickel oxides should focus on high-entropy modification,adaptation to extreme conditions,and the exploration of new preparation and modification methods.At the same time,efforts should be grounded in practical considerations and guided by target performance,aiming to improve various aspects of material performance for different application fields without compromising the high capacity inherent to ultra-high nickel oxide cathodes.

Among all the intercalation compounds, ultrahigh-Ni (Ni > 0.9) layered oxides are the most probable commercially available cathode materials, with the high specific capacity and high discharge plateau, for the next-generation high energy lithium-ion batteries. However, with increasing Ni content in the oxides, fast decay of both the discharge capacity and mid-point potential during cycling is unavoidable due to the structural instability, which is the critical obstacle for the commercialization of ultrahigh-Ni oxides, including apparent microcracks and intrinsic phase transitions. In this work, the ultrahigh-Ni LiNi0.96Mg0.01Al0.01Nb0.01Ca0.01O2 (NMANC) layered oxide is prepared based on the medium-entropy doping and morphological control. Specifically, the as-prepared NMANC oxide present the low-strain characteristics, with higher mechanical strength and better ductility, which is beneficial to suppress apparent microsphere cracks and intrinsic phase transitions of the oxide cathode during cycling. Furthermore, the volume change of NMANC oxide is only nearly one-seventh of that of the pristine LiNi0.96Co0.04O2 in a single charge/discharge process, resulting from dramatically dissipating the lattice strain accumulation along grain boundaries. Correspondingly, the low-strain NMANC oxide demonstrates superior capacity retention of 98.2%, 96.7%, and 92.5% at 1C rate over 100 cycles with an upper cutoff potential continuously increasing from 4.3V, to 4.4V and 4.5 V (vs Li/Li+), respectively. Consequently, this work provides an efficient strategy to design and stabilize ultrahigh-Ni layered oxides for high energy lithium-ion batteries.

High-voltage lithium-metal batteries offer exceptional energy density but suffer from poor stability due to challenges in ion transport and interfacial reactions. This work addresses these issues by designing a composite gel polymer electrolyte with a dielectric-gradient structure. This is achieved by incorporating nanofillers of contrasting dielectric constants into a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) matrix: high-dielectric NaNbO3 (NNO) particles near the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode to enhance bulk ion dissociation and concentration with a stable fluorinated Li/Na hybrid cathode-electrolyte interphase (CEI), low-dielectric Al2O3 particles near the metallic Li anode to increase the Li+ transference number and stabilize the interface, and a low concentration of NNO in the middle to facilitate smooth ion transfer. This spatially engineered configuration facilitates rapid ion conduction, suppresses lithium dendrite growth, and mitigates interfacial degradation. Consequently, the derived batteries exhibit outstanding cycling stability at a high cut-off voltage of 4.5 V (with a capacity retention rate as high as 66.22% after 1000 cycles at 5C) and remarkable rate capability (still maintaining a discharge specific capacity of 219.1 mAh g-1 at 3C), demonstrating a promising strategy for developing high-energy, durable lithium-metal batteries.

With deepening research on solid electrolytes, mechanical properties have been recognized to impact significantly on cells' performances and need to be intentionally enhanced. However, the intercorrelation of mechanical parameters and their modifications is still poorly understood. In this study, comprehensive mechanical characterizations are conducted on a series of typical PEO/LLZTO composite electrolytes. Each mechanical parameter under different deformation processes is obtained, including tensile, fracture, puncture, lap-shear, adhesion, and indentation. For the first time, change trends of these parameters are observed to reveal their intercorrelations. Interestingly, the mechanical resistances (elastic modulus, hardness, fracture energy, and puncturing force) could be adjusted toward the same direction, whereas the adhesive behaviors (shear strength and adhesion force) show an opposite trend. The mechanical resistance parameters show a decisive effect on the cell's cycling time, when they have a contradictory tendency with ionic conductivity. Also, different influences of synthesis conditions on mechanical properties are investigated systematically.

Accelerating lithium polysulfide conversion by catalytic effect of host materials in sulfur cathodes is an effective strategy for improving lithium sulfur batteries. In this work, amount of sulfur vacancies is quantitatively regulated to obtain MoS2-x with abundant defects mainly including atom vacancies and edge dislocations. It is found the defects can trigger phase transition from 2H-MoS2 to 1T-MoS2; more interestingly, the defects in 1T-MoS2 provide stronger catalytic ability for polysulfide conversion than those in 2H-MoS2. Furthermore, doping of cobalt in non-stoichiometric MoS2-x can stabilize 1T-MoS2 even with sulfur vacancies as high as 32 %. Acting as catalytically active sites, the abundant and stable defects significantly enhance electrochemical kinetic of the sulfur cathodes. The nitrogen-doped graphene-supported S/Co0.22-MoS1.36 electrode demonstrates an excellent long-cycle stability at 1C, remaining 591.8 mAh g-1 after 1200 cycles with a coulombic efficiency of 98.8 % and a decay rate of 0.032 %. Even under extreme conditions such as a high areal sulfur-loading of 14.3 mg cm-2 and lean electrolyte of 4 mu L mg-1, the S/Co0.22-MoS1.36 electrode achieves an initial areal capacity of 12.37 mAh cm-2 with satisfactory cycling stability. These results provide novel insight and an alternative approach to developing host materials for high-performance lithium sulfur batteries.

Lithium metal is regarded as a highly promising anode material owing to its ultrahigh theoretical capacity and low electrode potential. Unfortunately, significant concerns including poor Coulombic efficiency (CE) and uncontrolled Li dendritic growth severely hinder its development. Constructing a stable solid electrolyte interphase (SEI) on the electrode surface has been considered a practical and effective approach to settle the previous issues. In this study, 4-(trifluoromethyl)thiophenol (TFTP), an organic thiophenol, is introduced as an electrolyte additive to generate a lithiophilic organosulfur interphase with lithiophilic S sites through in situ reaction, guiding uniform Li nucleation and Li plating. Additionally, the generation of LiF/Li3N-rich layer during the cycling further facilitates homogeneous Li deposition. Therefore, the reliable SEI results in a uniform Li morphology and rapid kinetic of Li deposition. Benefiting from the TFTP electrolyte, the Li-Li symmetric cell exhibits a longlasting lifespan of 1200 h, and the full cell coupling with sulfur cathode shows a remarkable discharge capacity of 733.6 mAh g- 1 after 200 cycles.

The fast charging-discharging performance of power batteries has very practical significance. In terms of electrochemistry, this requires fast and stable kinetics for electrochemical reaction processes. Despite the great complexity of kinetics, it is clear that lithium-ion desolvation and a subsequent step of crossing through cathode-electrolyte interphase (CEI) are crucial to high-rate performance, in which the two key steps depend heavily on the working electrolyte formula. In this work, a customized electrolyte is developed to coordinate ion desolvation and interphase formation by introducing vinylene carbonate (VC), triphenylboroxin (TPBX), and fluoroethylene carbonate (FEC) but excluding ethylene carbonate (EC). Serving Ni-rich cathodes, the customized electrolyte generates a double-layered CEI, LiF-dominated inorganics inner layer, and ROCOOLi-dominated organics outer layer, which is not only stable and very efficient for lithium ion transport. Meanwhile, a PF6-${\mathrm{PF}}_6<^> - $-dominated solvation structure is induced and effectively decreases the desolvation energy to 29.72 kJ mol-1, supporting fast lithium ion transport in the cathode interfacial processes. Consequently, the Ni-rich lithium-ion battery achieves a stable long cycle at a superior high rate of 10 C.

Eutectic-based polymer electrolytes have emerged as promising solid electrolytes because of their ionic liquid-like properties, while modifications are essential to further increase their ionic conductivity at room temperature and solve their compatibility with lithium anode. In this work, an in situ polymerized composite electrolyte is modified by the addition of fluoroethylene carbonate (FEC) whose beneficial effect is systematically investigated in different contents. Poly(ethylene glycol) diacrylate (PEGDA), deep eutectic solvent (LiTFSI:N-methylacetamide = 1:3), and alumina fiber work as the monomer, solvent, and three-dimensional skeleton, respectively. In adjusting FEC content, ionic conductivity at room temperature is dramatically raised by three times to 8.93 × 10-4 S cm-1, with a 4-fold increase in lithium-ion transference number to 0.405. Meanwhile, the electrochemical window is widened from 3.5 to 4.8 V. The FEC addition also helps in improving the stability with Li anode, which comes from LiF-rich interphases formed at interfaces. The dynamics of LiFePO4 is significantly enhanced with higher reversibility in full cells, so that fast capacity decay is inhibited with a specific capacity of 124.1 mAh g-1 obtained after 300 cycles at 1 C. These results provide an effective modification for the deep eutectic electrolyte, which will boost its development in solid-state batteries.

A prefabricated matrix is normally used as the cathode host for lithium-sulfur batteries to address the shuttle effect problem. Unconventionally, herein we present a non-shaped matrix for a sulfur cathode that enables a better lithium-sulfur battery. The fast oxide-ion conductor La2Mo2O9 is introduced into the sulfur cathodes for the first time. Specifically, La2Mo2O9 is highly dispersed in sulfur to form a solid solution (LMO-in-S), in which the two components are homogenously mixed to a molecular level, which is completely different from the conventional model. The non-shaped matrix provides enormous surface contact with sulfur and high catalytic ability for the conversion of polysulfides to deliver a high discharge capacity and satisfactory cycle stability. LMO-in-S, which exhibits a high tap density, delivers a high gravimetric capacity of 1374.1 mAh g-1, corresponding to a volumetric capacity of 2294.8 mAh cm-3 at a 0.1C rate. Notably, LMO-in-S exhibits satisfactory cycle stability with a low fade rate of 0.07% per cycle over 400 cycles at 1C rate. Furthermore, it allows an ultra-high sulfur content (92.6 wt%) to deliver a high capacity of 1076.5 mAh g-1 at a 0.1C rate. Objectively, this work breaks through the original concept of sulfur cathode structures and provides a novel possibility for developing high-performance lithium-sulfur batteries.

All-solid-state lithium-sulfur batteries (ASSLSBs) using poly(ethylene oxide) (PEO) electrolytes offer significant advantages in energy density and safety. However, their development is hampered by the slow Li+ conduction in solid polymer electrolytes and sluggish electrochemical conversion at the cathode-electrolyte interface. Herein, we fabricate a self-healing poly(β-amino ester) with a comb-like topological structure and multiple functional groups, synthesized through a Michael addition strategy. This material modifies the PEO-based solid-state electrolyte, creating fast Li+ transport channels and improving polysulfides conversion kinetics at the electrode surface. Consequently, both modified all-solid-state lithium symmetric cells and lithium-sulfur batteries exhibit improved electrochemical performance. This work demonstrates an expanded interpenetrating macromolecular engineering approach to develop highly ion-conductive solid polymer electrolytes for ASSLSBs.

Compared with conventional liquid electrolytes, solid-state electrolytes in lithium-sulfur batteries can efficiently counteract shuttle effects and bolster safety. Gel polymer electrolytes (GPEs) can inherit the advantages of all-solid-state electrolytes while preserving high ionic conductivity and achieving excellent interface contact. In this study, solvent molecules within GPEs are classified as either free or bound solvents, with the quantity of free solvent molecules playing a crucial role in determining the viscosity of GPEs. An increase in the free solvent molecular viscosity significantly boosts the discharge capacity and rate performance; a lower Guttmann donor number (DN) facilitates capacity retention, and a higher dielectric constant (ε) promotes the reduction of internal polarization. The theoretical framework employed for selecting a GPE is proven to be highly effective, as evidenced by the exceptional electrochemical performance demonstrated by the chosen poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) electrolyte, providing valuable insights and encouraging further development of GPEs in lithium-sulfur batteries.

The poor lithium reversibility limits the development of high energy lithium metal batteries (LMBs), especially for anode-free LMBs. The root is the existence of the unstable interphase caused by its high reactivity, inducing dendrites and fragile solid-electrolyte interphase (SEI). Different from the common researches on SEI, this work focuses on intervening in the seed of SEI on Cu collector through lithium salt design to achieve dendrite-free dense lithium deposition. It is shown that lithium difluoro(oxalato)borate can induce a transitional SEI (T-SEI) on the Cu collector before lithium nucleation to promote the uniform and regular lithium nucleation. Moreover, assisting of lithium bis(trifluoromethanesulphonyl)imide and lithium nitrate, the T-SEI transforms into a mature SEI (M-SEI) rich in inorganic phase with lithium depositing, conducive to dendrite-free dense lithium deposition. This allows the anode-limited Li/NCM811 battery with N/P = 4 to cycle stably at 0.5C with a capacity retention above 95 % after 300 cycles.

Ni-rich layered oxide cathode materials are at the forefront of advancements in long-range electric vehicles. However, these materials confront significant challenges related to structural destabilization during cycling, especially when operated at elevated temperatures. Here we explore the intricate relationship between operating temperature, lattice resilience, and Ni content in Ni-rich cathodes. Our investigation emphasizes the crucial role of lattice thermal expansion in causing structural degradation and capacity fading of cathodes at elevated temperatures. The results reveal that higher Ni content intensifies the vulnerability of cathode structures to thermal expansion, particularly within the Li slabs, thereby expediting oxygen loss and phase transitions. To address the challenges associated with thermal-induced structural degradation, we propose introducing lattice distortion by incorporating large-radius elements, for example Na and La, to enhance the structural robustness of cathodes. The electrochemical results demonstrate that this strategy enables a Co-free ultrahigh-Ni cathode, Li0.99Na0.01Ni0.98La0.02O2, with a high discharge capacity (227.9 mAh g-1 at 0.1 C and 25 degrees C) and outstanding cycling stability (78.9 % capacity retention after 500 cycles at 1 C and 50 degrees C in pouch cells). These findings offer feasible guidance for boosting the performance of layered oxide cathodes under harsh conditions.

The most critical failures in solid-state batteries, including interfacial detachment, cracks, and dendrite growth are coupled with or fundamentally belong to a class of overarching phenomena that may be broadly defined as mechanical processes. However, current research on mechanical processes is far from sufficient, and is in its infancy compared with studies of improving electrolyte ionic transportation and electrochemical stabilities. Even the physical significance of many mechanical parameters has not been clarified in this field and the corresponding characterization methods have not yet been widely established. Herein, this review focuses on the intrinsic mechanical parameters associated with the design and operation of solid-state batteries and their characterization. Beginning with an overview of mechanical processes, key concepts in the context of solid-state batteries (SSB) are defined. Next, the various characterization methods that have been applied to SSBs are described in detail, and the key results are reviewed. Additional methods applied in orthogonal areas are also included to emphasize the possible translational impact on the solid-state battery field. Finally, perspectives on the challenges and development trends in mechanical characterization are proposed for further development in solid-state batteries.