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Solid‐state lithium metal batteries (SSLMBs) have gained extensive attraction as one kind of next‐generation energy storage device. However, the drawbacks of flammability, low mechanical strength, and low ionic conductivity limit the further development of solid‐state polymer electrolytes (SPEs). In this work, a reactive flame‐retardant unit into the polymer framework via covalent bonding to create a nonflammable and stretchable polyurethane‐based SPEs is introduced. Meanwhile, the mechanical strength of the polymer backbone is increased by grafting a rigid benzene ring unit, which remarkably suppresses the lithium‐dendrite growth. As a result, these inflammable SPEs do not burn after contact with flames for 6 s. Furthermore, the obtained SPE expands the electrochemical stability window up to 5.1 V. Small monomers containing bromine decompose on the surface of lithium metal creating a LiBr riched solid electrolyte interface (SEI). Li|SPEs|Li symmetric battery offers a stable cycling life for more than 2100 h at 0.2 mA cm−2 and 0.2 mAh cm−2. The LiNi0.6Co0.2Mn0.2O2|SPEs|Li cell equipped with the integrated cathode delivers a 142.1 mAh g−1 capacity after 330 cycles at 0.3 C with 85.2% capacity retention. [ABSTRACT FROM AUTHOR]

Sulfurized polyacrylonitrile (SPAN) is a very stable and promising sulfur‐based cathode material for high energy density lithium–sulfur (Li–S) batteries, which can circumvent the polysulfides dissolution issue. However, the stress concentration caused by volume change in SPAN cathodes is relatively significant but is rarely focused on. It is widely reckoned that the binder plays a key role in buffering the stress induced by electrode materials and hence maintains the integrity of electrodes. Nevertheless, the understanding of the actual effect of binders to SPAN cathodes from the aspect of mechanics remains to be deepened. Here, the optical fiber Bragg grating (FBG) is implanted into SPAN cathode films to in situ evaluate the electrochemo‐mechanical behaviors by using four different binders. The internal strain evolution of SPAN cathodes is affected by multiple factors of adhesion and mechanical properties of different binders. It is found that the SPAN cathode using poly(acrylic acid) (PAA) binder with outstanding mechanical properties experiences the largest strain change but the electrochemical performance is even better under high sulfur loading. Furthermore, the strain evolution is monitored under high sulfur loading condition and how the sulfur loading affects the signals of the built‐in FBG sensors is tried to figure out. [ABSTRACT FROM AUTHOR]

Solid‐state electrolytes paired with lithium‐metal anodes is considered a next‐generation energy storage technology. However, the slow ionic transportation of the solid‐state electrolyte and the instability against the lithium‐metal anode impede their practical application. Here a cellulose separator modified with highly uniform boric oxide solid acid, contributing to a high transference number (0.75) and good ionic conductivity of 0.52 mS cm−1 due to the strengthened binding of the salt anions with this solid acid, is reported. Moreover, the boron ions with occupied interstitial sites can release free electrons to regulate the electrochemical dynamics of the electrolyte, in situ inducing the formation of Li2CO3/LiF‐rich heterostructured solid electrolyte interphase layer. The cellulose/B2O3‐based composite electrolyte paired with LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode and Li‐metal anode displays a specific capacity of 155 mAh g−1 with a capacity retention of 92% in 200 cycles. Additionally, this electrolyte paired with high‐mass‐loading NCM622 cathode (10 mg cm−2) in a pouch cell can be stably operated for 50 cycles with a capacity retention of over 90%. [ABSTRACT FROM AUTHOR]

High‐temperature (HT) operation and storage performance of Li‐ion batteries (LIBs) are essential for applications in electric vehicles, grid storage, or defense missions. Unfortunately, severe capacity fading is witnessed due to growing instability of the electrode/electrolyte interphase at HT. Herein, the study liberates the electrolyte from the task of film‐formation. Instead, it takes advantage of the favorable solid‐electrolyte interphase (SEI)‐forming functional groups by priorly anchoring them on graphite surface. Specifically, via molecular design, unsaturated CC bond, together with amide and sulfonate groups, are concurrently involved, namely the lithium‐2‐acrylamido‐2‐methyl‐1‐propanesulfonate (Li‐AMPS). Upon electrochemical cycle, the unsaturated CC bond in Li‐AMPS turns into a radical that induces polymerization between CC bonds to construct a polymeric network. The presence of amide and sulfonate groups endows the SEI with nitrogen, sulfur‐based reduction products OSO2Li and Li3N, etc. As such, the designed interphase makes the use of propylene carbonate‐based electrolyte possible. By assembling full cells with the modified graphite and LiNi0.5Co0.2Mn0.3O2 (cathode loading of ≈18.5 mg cm−2), the capacity retention of the full cell has increased from 53.2% (with pristine graphite) to 77.8% after 300 cycles under 60 °C. A 2 Ah, 265 Wh kg−1 pouch cell is also able to operate for 200 cycles at an extreme temperature of 80 °C with the modified graphite. [ABSTRACT FROM AUTHOR]

Rare earth‐based halide solid electrolytes (RE‐HSEs) are noted due to their comprehensive properties of good ionic conductivity, electrochemical window, and deformability. However, the types and applications of RE‐HSEs need to be further expanded. Here, a highly purified RE‐HSE Li3ErBr6 (LErB) is synthesized successfully by a vacuum evaporation method. The prepared LErB possesses a high ionic conductivity of 1.0 mS cm−1 with an electrochemical window of 1.5–3.4 V. The LErB is applied in a solid Li–SeS2 battery, which can realize stable cycling performance for 300 cycles and good rate performance at room temperature. Moreover, to evaluate the practicability of the LErB‐based Li–SeS2 battery, a pouch‐type cell is assembled, which can light a diode array even after bending and cutting. These results demonstrate that LErB‐based solid Li–SeS2 cells possess advantages in battery packaging and operation, which can improve the practicability of all‐solid‐state lithium batteries. [ABSTRACT FROM AUTHOR]

The stability of Pt‐based catalysts for oxygen reduction reaction (ORR) in hydrogen fuel cells is seriously handicapped by the corrosion of their carbon supports at high potentials and acidic environments. Herein, a novel SnS2/SnO2 hetero‐structured support is reported for Pt nanoparticles (NPs) as the ORR catalyst, where Pt NPs are mainly deposited at the interfaces of SnS2 and SnO2 moieties. The Pt‐support interactions, which can be tuned by the concentration of the heterointerfaces, can accelerate the electronic transfer and enrich the electron density of Pt with a favorable shift of the d‐band center. In electrochemical measurements, the ORR mass activity (MA) of the optimal Pt‐SnS2/SnO2 catalyst at 0.9 V versus RHE (0.40 A mgPt−1) is four times higher than that of Pt/C. As for the stability, the electrochemical active surface area and MA of Pt‐SnS2/SnO2 are only decreased by 18.2% and 23.7% after 50 000 potential cycles at a high potential region (1.0–1.6 V), representing the best ORR stability among the reported Pt‐based catalysts. Density functional theory calculations indicate that the binding energy and migration barrier of Pt atom/cluster on the SnS2/SnO2 heterojunction are much higher relative to other supports, accounting for the outstanding stability of the catalyst. [ABSTRACT FROM AUTHOR]

In the spinel oxide cathode family, LiNi0.5Mn1.5O4 (LNMO) shows a high operating voltage (≈4.7 V vs Li/Li+) and excellent Li‐ion mobility with stable 3D conducting channels. Ni/Mn cation disordered and ordered phases usually coexist in LNMO materials, and they have distinct structural and electrochemical properties, resulting in different battery performances for LNMO materials with different phase compositions. Identifying the correlation between phase compositions and electrochemical properties is of significance to the improvement of battery performance and understanding of degradation mechanisms. Herein, the disordered/ordered phase compositions in LNMO materials are tailored by post‐annealing strategies and their impacts on electrochemical performance and degradation mechanisms from the surface to the bulk are systematically investigated. The ordered phase increases rapidly as Mn3+ is oxidized to Mn4+ through a post‐annealing process. LNMO with an intermediate fraction of disordered and ordered phases gives rise to improved cycling stability. This article further reports that a high ordered phase fraction can preferentially protect Ni from dissolution during cycling. However, these results suggest that the transition metal dissolution and surface structural change of LNMO do not exhibit a direct correlation with cycling stability. These results indicate the capacity fading mainly correlates with the bulk structural distortion, leading to decreased Li‐ion kinetics. [ABSTRACT FROM AUTHOR]

Garnet‐type Li6.4La3Zr1.4Ta0.6O12 (LLZTaO) is considered a promising solid‐state electrolyte (SSE) for all‐solid‐state batteries (SSBs), but LLZTaO/Li interfacial issues limit their power density. The key question of whether LLZTaO does or does not form an interphase layer before and at the initial stage of electrochemical cycling remains debatable. An XPS interface approach, electrochemical cycling, and an electrochemically coupled phase field model to study the dynamic changes of interfacial resistance during cycling are utilized, and it is found that the generation rate of the interphase via electrochemical reaction processes at the LLZTaO/Li interface depends on the applied current density. For a Li/LLZTaO/Li cell, the impedance and overpotential increase gradually at the initial stage of electrochemical cycling at a current density of 0.1 mA cm–2 due to the formation of a passivating reaction zone (interphase) at LLZTaO/Li interface, which can protect the LLZTaO from being continuously reacted. With increasing the current density to 0.5 mA cm–2, the electrochemical reaction is suppressed and tied to uneven Li ion transport across the LLZTaO/Li interface on plating, leading to a short circuit of the cell. Understanding how interface dynamic transformations influence electrochemical degradation is helpful to stabilize these interfaces in SSBs. [ABSTRACT FROM AUTHOR]

A self‐supporting Al foil anode should be attractive to the lithium‐ion battery (LIB) industry. However, initial attempts at using thin Al foil directly as a LIB anode ends up with extremely large initial Coulombic inefficiency and gross mechanical failures in just a few cycles. This feels incongruent with the expectation that face‐centered cubic Al should have good ductility. In this study, the discrepancy between "electrochemical ductility" and "mechanical ductility" is explained. Unlike "mechanical ductility" based on dislocation slip inside each grain, here it is proposed that "electrochemical ductility" of such high‐capacity alloy foil electrodes should be related to grain boundaries (GB) activities. It is found that after reducing the grain size D > 50 µm of the starting Al foil by shot‐peening treatment, higher GB density (e.g., smaller initial grain size D < 20 µm) greatly alleviates the initial porosity damage after the roll‐to‐roll mechanical prelithiation and significantly improves electrochemical ductility thereafter, with enhanced cycle life in various kinds of full cells. LixAl foil also demonstrates surprising air stability with negligible capacity loss even after several hours' exposure to air. Such thin prelithiated metallic foil anodes are therefore highly competitive against pure Li metal foils. [ABSTRACT FROM AUTHOR]

The practical application of lithium metal anode has been hindered by safety and cyclability issues due to the uncontrollable dendrite growth, especially during fast cycling and deep plating/stripping process. Here, a composite Li metal anode supported by periodic, perpendicular, and lithiophilic TiO2/poly(vinyl pyrrolidone) (PVP) nanofibers via a facial rolling process is reported. TiO2/PVP nanofibers with good Li affinity provide low‐tortuosity and directly inward Li+ transport paths to facilitate Li nucleation and deposition under high areal capacities and current densities. The micrometer‐scale interspaces between TiO2/PVP walls offer enough space to circumvent the huge volume variation and avoid structure collapsing during the repeated deep Li plating/stripping. The unique structure enables stable cycling under ultrahigh currents (12 mA cm−2), and ultra‐deep plating/stripping up to 60 mAh cm−2 with a long cycle life in commercial carbonate electrolytes. The gassing behavior in operating pouch cells is observed using ultrasonic transmission mapping. When paired with LiFePO4 (5 mAh cm−2), sulfur (3 mAh cm−2), and high‐voltage LiNi0.8Co0.1Mn0.1O2 cathodes, the composite Li anodes deliver remarkably improved rate performance and cycling stability, demonstrating that it could be a promising strategy for balancing high‐energy density and high‐power density in Li metal batteries. [ABSTRACT FROM AUTHOR]

Manganese‐based materials are considered potential cathode materials for aqueous zinc ion batteries (ZIBs). However, the dissolution of manganese leading to an abrupt decline of capacity and the sluggish electrochemical reaction kinetics are still the main bottlenecks restricting their further development. Herein, a NiMn‐layered double hydroxide‐derived Ni‐doped Mn2O3 (NM) is developed to suppress the dissolution of manganese. The incorporation of Ni2+ can promote electronic rearrangement and enhance the conductivity, ultimately improving the reaction kinetics and electrochemical performance of the NM. Moreover, the doped Ni2+ can effectively stabilize the MnO bond of Mn2O3 by reducing the formation energy. In addition, the storage mechanism based on the simultaneous insertion and transformation of H+ and Zn2+ is demonstrated. Interestingly, the Ni‐doped Mn2O3 shows a high specific capacity of 252 mAh g–1 (0.1 A g–1), three times more than the pure Mn2O3 (72 mAh g–1). The capacity retention (≈85.6% over 2500 cycles at 1.0 A g–1) is also more excellent when comparing with the Mn2O3 cathode (≈49.7%). Significantly, an ultra‐high energy density of 327.6 Wh kg–1 has been achieved using Ni‐doped Mn2O3 cathode, which suggests that the synergistic effect of manganese and other transition metal ions provide a promising strategy for future development of ZIBs. [ABSTRACT FROM AUTHOR]

Alkali metal–chalcogen batteries (ACBs) have attracted significant attention as next‐generation energy storages because of high energy density and reasonable cost as compared to the up‐to‐date lithium‐ion batteries. Nevertheless, their practical applications are harshly inhibited by some drawbacks, such as shuttle effects resulting from dissolved polysulfides and polyselenides, chalcogen volume expansion, and dendrite growth on metal anodes. Functional components, such as chalcogen host, binder, and interlayer, using various polar materials have been introduced to address these issues. Among them, bio‐derived materials are regarded as novel eco‐friendly alternatives. In this report, the authors focus on the unique physical/chemical/environmental properties of bio‐derived materials used in ACBs, including active host materials, polymer binders, separators, and additives. The authors hope that the present report can provide some new insights and directions for future research on high‐performance ACBs. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are promising next‐generation rechargeable batteries due to thier high energy density, low cost, and environmental friendliness. However, the extremely low electrical conductivity of sulfur and the dissolution of polysulfides limit their actual electrochemical performances, especially in the case of high sulfur mass loading. Here, a new strategy based on intrinsic point defects of materials is proposed to simultaneously enhance the electrical conductivity of active material and regulate the migration of polysulfides. Taking advantage of ultrathin and lightweight Bi2Te2.7Se0.3 (BTS) interlayers with high‐density antisite defects on the separator surface, the Li–S battery with BTS interlayer shows a capacity of 756 mAh g−1 at 2C and a low capacity decay rate of 0.1% over 300 cycles. The BTS interlayer can not only enhance the active material utilization but also improve capacity retention. The defect engineering strategy accompanied with facile method is promising for the development of advanced Li–S batteries for practical application. [ABSTRACT FROM AUTHOR]

To tackle the issue of inferior cycle stability and rate capability for MnO anode materials in lithium ion batteries, a facile strategy is explored to prepare a hybrid material consisting of MnO nanocrystals grown on conductive graphene nanosheets. The prepared MnO/graphene hybrid anode exhibits a reversible capacity as high as 2014.1 mAh g−1 after 150 discharge/charge cycles at 200 mA g−1, excellent rate capability (625.8 mAh g−1 at 3000 mA g−1), and superior cyclability (843.3 mAh g−1 even after 400 discharge/charge cycles at 2000 mA g−1 with only 0.01% capacity loss per cycle). The results suggest that the reconstruction of the MnO/graphene electrodes is intrinsic due to conversion reactions. A long-term stable nanoarchitecture of graphene-supported ultrafine manganese oxide nanoparticles is formed upon cycling, which yields a long-life anode material for lithium ion batteries. The lithiation and delithiation behavior suggests that the further oxidation of Mn( II) to Mn( IV) and the interfacial lithium storage upon cycling contribute to the enhanced specific capacity. The excellent rate capability benefits from the presence of conductive graphene and a short transportation length for both lithium ions and electrons. Moreover, the as-formed hybrid nanostructure of MnO on graphene may help achieve faster kinetics of conversion reactions. [ABSTRACT FROM AUTHOR]

Lithium iron phosphate (LiFePO4) is a widely utilized cathode material in lithium‐ion batteries, prized for its safety, low cost, and extensive cycling lifespan. However, its low compaction density limits its application in batteries requiring high volumetric energy density. The inclusion of conductive carbon black in electrodes, while increasing porosity, also exacerbates side reactions due to its high specific surface area. In this study, the use of liquid metal (GaIn) nanoparticles is explored as a substitute for carbon black in electrode formulations. GaIn nanoparticles' stable oxide film prevents oxidation at cathode potential. Additionally, liquid metal improves the particle interface to a solid‐liquid interface, reducing particle friction and providing a lubricating effect, resulting in a denser electrode structure. As a result, the porosity of LiFePO4 electrodes prepared with liquid metal is reduced, leading to a 20.7% increase in volumetric energy density. Moreover, GaIn‐containing batteries exhibit fewer side reactions, especially at elevated temperatures in both liquid and solid battery configurations. Solid‐state batteries employing GaIn nanoparticles demonstrate a specific capacity of 144 mAh g−1 at 0.5C, showcasing superior cycling performance compared to traditional formulations. This underscores the potential of GaIn to elevate the performance of LiFePO4 batteries. [ABSTRACT FROM AUTHOR]

Using a solid‐state electrolyte (SSE) to stabilize the Li metal anode is widely considered a promising route to develop next‐generation high energy density lithium batteries. Here, a new polycrystalline aluminate‐based SSE (named Li–Al–O SSE) with good capability is introduced to protect Li metal. The SSE is formed on the Li metal surface via a chemical reaction between LiOH and triethylaluminum (TEAL) with the existence of LiTFSI‐based electrolyte. It is a continuous film that consists of polycrystalline LiAlO2, Li3AlO3, Al2O3, Li2CO3, LiF, and some organic compounds. Such Li–Al–O SSE possesses a room‐temperature ionic conductivity as high as 1.42 × 10−4 S cm−1. Meanwhile, it effectively protects the Li anode from the corrosion of H2O, O2, and organic solvent, and suppresses the growth of Li dendrite. With the protection of the Li–Al–O SSE, the cycle life of Li|Li symmetric cell and Li|O2 cell is substantially elongated, indicating that the SSE exhibits an excellent protective effect under both inert and oxidizing circumstances. [ABSTRACT FROM AUTHOR]

Silicon is widely recognized as an ideal anode material due to its high specific capacity, low lithiation potential, high abundance, and environmental friendliness. Nevertheless, the immense volume expansion during the lithiation leads to pulverization of silicon particles, which causes electrode failure with a rapid capacity decay. Herein, the polymerized 1, 3‐dioxolane (PDOL) electrolyte is used to stabilize the micro‐silicon Si anode via in situ polymerization route. The conformality of the quasi‐solid electrolyte suppresses the pulverization of the Si microparticles (SiMPs) effectively and thus alleviates the capacity decay. The SiMPs/PDOL anode shows an excellent initial CE of 97.5% and maintains a reversible capacity of 1837.1 mAh g−1 at 500 mA g−1 after 100 cycles. The Si/PDOL/LiFePO4 full cells also exhibit a stable cycling performance with a capacity retention of 76.3% after 300 cycles. This work provides a new and easy path for the practical application of silicon anode at low cost. [ABSTRACT FROM AUTHOR]