A Flexible Ceramic/Polymer Hybrid Solid Electrolyte for Solid-State Lithium Metal Batteries

Enhanced electrochemical stability and ion transfer rate: A polymer/ceramic composite electrolyte for high-performance all-solid-state lithium-sulfur batteries

All-solid-state (ASS) lithium-sulfur (LiS) batteries utilizing composite polymer electrolytes (CPEs) represent a promising avenue in the domain of electric vehicles and large-scale energy storage systems, leveraging the combined benefits of polymer electrolytes (PEs) and ceramic electrolytes (CEs). However, the inherent weak interface compatibility between PEs and CEs often leads to phase separation, thereby impeding the transposition of Li+. In this study, the trimethoxy-[3-(2-methoxyethoxy)propyl]silane (TM-MES) is introduced as a chemical agent to form bonds with polyethylene oxide (PEO) and Li10GeP2S12 (LGPS), resulting in the development of a novel composite polymer electrolyte (CPETM-MES). This innovative approach mitigates phase separation between PEs and CEs while concurrently enhancing the protective capabilities of LGPS against decomposition at the interfaces of both the Li anode and sulfur cathode. Moreover, the CPETM-MES exhibits superior mechanical toughness, an expanded electrochemical window, and elevated ionic conductivity. In the symmetric cell, it demonstrates an extended operational lifespan exceeding 1800 h, and the current density can reach up to 1.05 mA/cm2. Furthermore, the initial discharge capacity of ASS LiS batteries utilizing CPETM-MES attains 1227 mAh/g and maintains a capacity of 904 mAh/g after 100 cycles. Notably, a high-energy-density of 2454 Wh/kg is achieved based on the sulfur cathode.

A self-healing composite solid electrolyte with dynamic three-dimensional inorganic/organic hybrid network for flexible all-solid-state lithium metal batteries

Composite solid electrolytes (CSEs), which combine the advantages of solid polymer electrolytes and inorganic solid electrolytes, are considered to be promising electrolytes for all-solid-state lithium metal batteries. However, the current CSEs suffer from defects such as poor inorganic/organic interface compatibility, lithium dendrite growth, and easy damage of electrolyte membrane, which hinder the practical application of CSEs. Herein, a CSE (PBHL@LLZTO@DDB) with polyurethane (PBHL) as the polymer matrix and Li6.4La3Zr1.4Ta0.6O12 (LLZTO) modified by silane coupling agent (DDB) as inorganic fillers (LLZTO@DDB) has been prepared. Disulfide bond exchange reactions between PBHL and LLZTO@DDB enable PBHL@LLZTO@DDB to form a dynamic three-dimensional (3D) inorganic/organic hybrid network, which promotes the uniform dispersion of LLZTO in PBHL@LLZTO@DDB, improves the Li+ conductivity (1.24 ± 0.08 × 10-4 S cm-1 at 30 ℃), and broadens the electrochemical stability window (5.16 V vs. Li+/Li). Moreover, a combination of hydrogen bonds and disulfide bonds endows PBHL@LLZTO@DDB with excellent self-healing properties. As such, both all-solid-state symmetric and full cells exhibit excellent cycle performance at ambient temperature. More importantly, the healed PBHL@LLZTO@DDB can almost completely restore its original electrochemical properties, indicating its application potential in flexible electronic products.

Protecting Li-metal anode with LiF-enriched solid electrolyte interphase derived from a fluorinated graphene additive

As the holy-grail material, the Li-metal anode has been considered the potential anode of the next generation of Li-metal batteries (LMBs). However, issues of undesirable dendrite growth and unsatisfactory reversibility of the Li-plating/stripping process during the electrochemical cycling impede further application of LMBs. Herein, we innovatively introduce fluorinated graphene (F-Gr) species as a sacrificial effective electrolyte additive into EC/EMC-based electrolyte, which effectively triggers LiF-enriched (composition) and organic/inorganic species uniform-distributed (structure) SEI film architecture that features robustness and denseness, as well as good stability. With the F-Gr additive, efficient Li-metal anode protection (dendrite-free morphology on Li-metal surface and improved Li plating/stripping reversibility during electrochemical cycling) and significantly enhanced long-term lifespan of LMBs is achieved. Remarkably, classical electrochemical techniques, combined with the surface-sensitive characterizations (XPS and TOF-SIMS), comprehensively and systematically highlight critical structure-activity relationships between the SEI architecture (both composition and structure) and electrochemical performance. These techniques provide deep insights into the optimal electrolyte designation of Li-metal anode in LMBs.

SnF2-Catalyzed Lithiophilic-Lithiophobic Gradient Interface for High-Rate PEO-Based All-Solid-State Batteries

Polyethylene oxide (PEO)-based all-solid-state lithium metal batteries (ASSLMBs) are strongly hindered by the fast dendrite growth at the Li metal/electrolyte interface, especially under large rates. The above issue stems from the suboptimal interfacial chemistry and poor Li+ transport kinetics during cycling. Herein, a SnF2-catalyzed lithiophilic-lithiophobic gradient solid electrolyte interphase (SCG-SEI) of LixSny/LiF-Li2O is in situ formed. The superior ionic LiF-Li2O rich upper layer (17.1 nm) possesses high interfacial energy and fast Li+ diffusion channels, wherein lithiophilic LixSny alloy layer (8.4 nm) could highly reduce the nucleation overpotential with lower diffusion barrier and promote rapid electron transportation for reversible Li+ plating/stripping. Simultaneously, the insoluble SnF2-coordinated PEO promotes the rapid Li+ ion transport in the bulk phase. As a result, an over 46.7 and 3.5 times improvements for lifespan and critical current density of symmetrical cells are achieved, respectively. Furthermore, LiFePO4-based ASSLMBs deliver a recorded cycling performance at 5 C (over 1000 cycles with a capacity retention of 80.0 %). More importantly, impressive electrochemical performances and safety tests with LiNi0.8Mn0.1Co0.1O2 and pouch cell with LiFePO4, even under extreme conditions (i.e., 100 °C), are also demonstrated, reconfirmed the importance of lithiophilic-lithiophobic gradient interfacial chemistry in the design of high-rate ASSLMBs for safety applications.

Advancements and Challenges in Organic-Inorganic Composite Solid Electrolytes for All-Solid-State Lithium Batteries

To address the limitations of contemporary lithium-ion batteries, particularly their low energy density and safety concerns, all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming alternative. Among the various SEs, organic-inorganic composite solid electrolytes (OICSEs) that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale applications. However, OICSEs still face many challenges in practical applications, such as low ionic conductivity and poor interfacial stability, which severely limit their applications. This review provides a comprehensive overview of recent research advancements in OICSEs. Specifically, the influence of inorganic fillers on the main functional parameters of OICSEs, including ionic conductivity, Li+ transfer number, mechanical strength, electrochemical stability, electronic conductivity, and thermal stability are systematically discussed. The lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic perspective. Besides, the classic inorganic filler types, including both inert and active fillers, are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of OICSEs. Finally, the advanced characterization techniques relevant to OICSEs are summarized, and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLBs.

Free Volume Mediated Decoupling of Ionic Conduction from Segmental Relaxation Leading to Enhancement in Ionic Conductivity of Polymer Electrolytes at Low Temperatures

Coupling between segmental relaxation and ionic conduction has limited the ionic conductivity of flexible polymers like poly(ethylene oxide), PEO, based electrolytes especially at low temperatures where segmental relaxation becomes extremely slow. In the present study, we show that ionic conduction becomes decoupled from segmental relaxation in PEO-based electrolytes simply by loading succinonitrile (SN). As a result of SN interactions induced rigid chain packing of PEO, the semicrystalline morphology of PEO is completely altered along with the enhancement in number density of free volumes having smaller size and narrower size distribution. These free volumes provide additional pathways for ionic diffusion independent of segmental relaxations of PEO leading to decoupling of ionic diffusion from the segmental relaxation process. The decoupling finally leads to nearly two orders higher ionic conductivity (∼10-11 Scm-1)at glass transition temperature (Tg ∼ 210 K), than what is expected in the case of complete coupling.

In-Situ Synthesized Gel Polymer Electrolyte Enable High Capacity and Long-Cycle-Life Lithium Metal Batteries

Solid-state lithium-metal batteries (SSLMBs) have attracted great attention due to their outstanding advantages in safety, electrochemical stability and interfacial compatibility. However, the low ionic conductivity and narrow electrochemical window restrict their practical application. Herein, in-situ polymerization electrolytes (IPEs) crosslinked by acrylonitrile (AN) and ethylene glycol dimethacrylate (EGDMA) exhibit the superior ionic conductivity of 1.77×10-3 S cm-1 at 25 °C, the ultrahigh lithium transference number (tLi+) of 0.784 and the wider electrochemical stable window (ESW) of 5.65 V. The IPEs make the symmetrical Li||Li cells achieve the highly stable lithium stripping/plating cycling for over 3000 h at 0.1 mA cm-2. Meanwhile, IPE endows the solid-state LiFePO4||Li batteries with an excellent long-cycle performance over 700 cycles at 2.5 C with a capacity retention ratio over 95 %, as well as 1000 cycles at 1 C and superior capacity retention of 85 %. More importantly, the in-situ polymerized electrolytes containing polyacrylonitrile (PAN) open up a new frontier to promote the practical application of solid-state batteries with high safety and high energy density via in-situ solidification technology.

Design of Quasi-Metal-Organic Frameworks for Solid Polymer Electrolytes Enabling an Ultra-Stable Interface with Li Metal Anode

Solid polymer electrolytes (SPEs) are crucial in the development of lithium metal batteries. Recently, metal-organic frameworks (MOFs) with open metal sites (OMSs) have shown promise as solid fillers to improve the performance of SPEs. However, the number of OMS-containing MOFs is quite limited, comprising less than 5% of the total MOFs. When considering yield, cost, and processability, the commonly used OMS-containing MOFs are no more than 10 types, causing great limitations. Herein, we reported a simple and universal methodology that converted OMS-free MOFs to OMS-rich quasi-MOFs for developing high-performance SPEs, and explored the underlying mechanism. The "OMS-polymer" and "OMS-ion" interactions were investigated in detail to elucidate the role of quasi-MOFs on battery performance. It was found that quasi-MOFs, functioning as ion sieves, can effectively regulate ion migration, thus promoting uniform Li deposition and enabling an ultra-stable interface. As a result, the Li symmetric cell stably ran over 3000 h at 0.3 mA cm-2, while the full cell retained 85 % of its initial capacity after 1500 cycles at 1.0 C. Finally, universal testing was performed using other MOFs, confirming the generalizability and effectiveness of our design concept.

Highly Ionic Conductive, Self-Healing, Li10GeP2S12-Filled Composite Solid Electrolytes Based on Reversibly Interlocked Macromolecule Networks for Lithium Metal Batteries with Improved Cycling Stability

Ceramic-polymer composite solid electrolytes (CSEs) have attracted great attention by combining the advantages of polymer electrolytes and inorganic ceramic electrolytes. Herein, Li10GeP2S12 (LGPS) particles are incorporated into poly(ethylene oxide) (PEO)-based reversibly interlocked polymer networks (RILNs) derived from the topological rearrangement of two PEO networks cross-linked by reversible imine bonds and disulfide linkages. A series of highly ionic conductive, self-healing CSEs are obtained accordingly. The interlocking architecture successfully inhibits PEO crystallization, increasing the amorphous phase for Li ion transportation, and stabilizes the conductive pathways of LGPS particles by its unique confinement effect. Meanwhile, the LGPS particles cooperate with the RILN matrix, forming a filler-polymer interfacial phase for additional Li ion transportation and strengthening and toughening the resultant CSEs via the strong intermolecular Li+-O2- interactions. Furthermore, the dynamic characteristics of the included reversible bonds ensure a multiple intrinsic self-healing capability. Consequently, the CSEs containing 15 wt % LGPS deliver a high ionic conductivity (1.06 × 10-3 S cm-1) and high Li ion transference number (∼0.6) at 25 °C, a wide electrochemical stability window (>4.9 V), good mechanical properties (0.63 MPa, 377%), and a stable CSE/Li anode interface. The integrated Li/CSE/LiFePO4 battery exhibits a specific discharge capacity of 110.8 mAh g-1 at 1 C (25 °C) and a capacity retention of 76.9% after 200 cycles. Thanks to the healability, the damaged CSEs can regain the structural integrity, ion conductive capability, and cycling performance of the assembled cells. The present work provides an effective strategy to fabricate CSEs for lithium metal batteries that are workable at ambient temperature.

Small Additives Make Big Differences: A Review on Advanced Additives for High-Performance Solid-State Li Metal Batteries

Solid-state lithium (Li) metal batteries, represent a significant advancement in energy storage technology, offering higher energy densities and enhanced safety over traditional Li-ion batteries. However, solid-state electrolytes (SSEs) face critical challenges such as lower ionic conductivity, poor stability at the electrode-electrolyte interface, and dendrite formation, potentially leading to short circuits and battery failure. The introduction of additives into SSEs has emerged as a transformative approach to address these challenges. A small amount of additives, encompassing a range from inorganic and organic materials to nanostructures, effectively improve ionic conductivity, drawing it nearer to that of their liquid counterparts, and strengthen mechanical properties to prevent cracking of SSEs and maintain stable interfaces. Importantly, they also play a critical role in inhibiting the growth of dendritic Li, thereby enhancing the safety and extending the lifespan of the batteries. In this review, the wide variety of additives that have been investigated, is comprehensively explored, emphasizing how they can be effectively incorporated into SSEs. By dissecting the operational mechanisms of these additives, the review hopes to provide valuable insights that can help researchers in developing more effective SSEs, leading to the creation of more efficient and reliable solid-state Li metal batteries.

Research Progress on the Composite Methods of Composite Electrolytes for Solid-State Lithium Batteries

In the current challenging energy storage and conversion landscape, solid-state lithium metal batteries with high energy conversion efficiency, high energy density, and high safety stand out. Due to the limitations of material properties, it is difficult to achieve the ideal requirements of solid electrolytes with a single-phase electrolyte. A composite solid electrolyte is composed of two or more different materials. Composite electrolytes can simultaneously offer the advantages of multiple materials. Through different composite methods, the merits of various materials can be incorporated into the most essential part of the battery in a specific form. Currently, more and more researchers are focusing on composite methods for combining components in composite electrolytes. The ion transport capacity, interface stability, machinability, and safety of electrolytes can be significantly improved by selecting appropriate composite methods. This review summarizes the composite methods used for the components of composite electrolytes, such as filler blending, embedded framework, and multilayer bonding. It also discusses the future development trends of all-solid-state lithium batteries (ASSLBs).

Metal-Organic Framework-Derived Co9S8 Nanowall Array Embellished Polypropylene Separator for Dendrite-Free Lithium Metal Anodes

Developing a reasonable design of a lithiophilic artificial solid electrolyte interphase (SEI) to induce the uniform deposition of Li+ ions and improve the Coulombic efficiency and energy density of batteries is a key task for the development of high-performance lithium metal anodes. Herein, a high-performance separator for lithium metal anodes was designed by the in situ growth of a metal-organic framework (MOF)-derived transition metal sulfide array as an artificial SEI on polypropylene separators (denoted as Co9S8-PP). The high ionic conductivity and excellent morphology provided a convenient transport path and fast charge transfer kinetics for lithium ions. The experimental data illustrate that, compared with commercial polypropylene separators, the Li//Cu half-cell with a Co9S8-PP separator can be cycled stably for 2000 h at 1 mA cm-2 and 1 mAh cm-2. Meanwhile, a Li//LiFePO4 full cell with a Co9S8-PP separator exhibits ultra-long cycle stability at 0.2 C with an initial capacity of 148 mAh g-1 and maintains 74% capacity after 1000 cycles. This work provides some new strategies for using transition metal sulfides to induce the uniform deposition of lithium ions to create high-performance lithium metal batteries.

Carbon carrier-based rapid Joule heating technology: a review on the preparation and applications of functional nanomaterials

Compared to conventional heating techniques, the carbon carrier-based rapid Joule heating (CJH) method is a new class of technologies that offer significantly higher heating rates and ultra-high temperatures. Over the past few decades, CJH technology has spawned several techniques with similar principles for different application scenarios, including ultra-fast high temperature sintering (UHS), carbon thermal shock (CTS), and flash Joule heating (FJH), which have been widely used in material preparation research studies. Functional nanomaterials are a popular direction of research today, mainly including nanometallic materials, nanosilica materials, nanoceramic materials and nanocarbon materials. These materials exhibit unique physical, chemical, and biological properties, including a high specific surface area, strength, thermal stability, and biocompatibility, making them ideal for diverse applications across various fields. The CJH method is a remarkable approach to producing functional nanomaterials that has attracted attention for its significant advantages. This paper aims to delve into the fundamental principles of CJH and elucidate the efficient preparation of functional nanomaterials with superior properties using this technique. The paper is organized into three sections, each dedicated to introducing the process and characteristics of CJH technology for the preparation of three distinct material types: carbon-based nanomaterials, inorganic non-metallic materials, and metallic materials. We discuss the distinctions and merits of the CJH method compared to alternative techniques in the preparation of these materials, along with a thorough examination of their properties. Furthermore, the potential applications of these materials are highlighted. In conclusion, this paper concludes with a discussion on the future research trends and development prospects of CJH technology.

Ultralong Cycling and Interfacial Regulation of Bilayer Heterogeneous Composite Solid-State Electrolytes in Lithium Metal Batteries

Under the background of "carbon neutral", lithium-ion batteries (LIB) have been widely used in portable electronic devices and large-scale energy storage systems, but the current commercial electrolyte is mainly liquid organic compounds, which have serious safety risks. In this paper, a bilayer heterogeneous composite solid-state electrolyte (PLPE) was constructed with the 3D LiX zeolite nanofiber (LiX-NF) layer and in-situ interfacial layer, which greatly extends the life span of lithium metal batteries (LMB). LiX-NF not only offers a continuous fast path for Li+, but also zeolite's Lewis acid-base interaction can immobilize large anions, which significantly improves the electrochemical performance of the electrolyte. In addition, the in-situ interfacial layer at the electrode-electrolyte interface can effectively facilitate the uniform deposition of Li+ and inhibit the growth of lithium dendrites. As a result, the Li/Li battery assembled with PLPE can be stably cycled for more than 2500 h at 0.1 mA cm-2. Meanwhile, the initial discharge capacity of the LiFePO4/PLPE/Li battery can be 162.43 mAh g-1 at 0.5 C, and the capacity retention rate is 82.74% after 500 cycles. These results emphasize that this bilayer heterogeneous composite solid-state electrolyte has distinct properties and shows excellent potential for application in LMB.

Wide-Temperature and High-Rate Operation of Lithium Metal Batteries Enabled by an Ionic Liquid Functionalized Quasi-Solid-State Electrolyte

The development of high-energy-density solid-state lithium metal battery has been hindered by the unstable cycling of Ni-rich cathodes at high rate and limited wide-temperatures adoptability. In this study, an ionic liquid functionalized quasi-solid-state electrolyte (FQSE) is prepared to address these challenges. The FQSE features a semi-immobilized ionic liquid capable of anchoring solvent molecules through electrostatic interactions, which facilitates Li+ desolvation and reduces deleterious solvent-cathode reactions. The FQSE exhibits impressive electrochemical characteristics, including high ionic conductivity (1.9 mS cm-1 at 30 °C and 0.2 mS cm-1 at -30 °C) and a Li+ transfer number of 0.7. Consequently, Li/NCM811 cells incorporating FQSE demonstrate exceptional stability during high-rate cycling, enduring 700 cycles at 1 C. Notably, the Li/LFP cells with FQSE maintain high capacity across a wide temperature range, from -30 to 60 °C. This research provides a new way to promote the practical application of high-energy lithium metal batteries.

Super-Ionic Conductor Soft Filler Promotes Li+ Transport in Integrated Cathode-Electrolyte for Solid-State Battery at Room Temperature

Composite polymer solid electrolytes (CPEs), possessing good rigid flexible, are expected to be used in solid-state lithium-metal batteries. The integration of fillers into polymer matrices emerges as a dominant strategy to improve Li+ transport and form a Li+-conducting electrode-electrolyte interface. However, challenges arise as traditional fillers: 1) inorganic fillers, characterized by high interfacial energy, induce agglomeration; 2) organic fillers, with elevated crystallinity, impede intrinsic ionic conductivity, both severely hindering Li+ migration. Here, a concept of super-ionic conductor soft filler, utilizing a Li+ conductivity nanocellulose (Li-NC) as a model, is introduced which exhibits super-ionic conductivity. Li-NC anchors anions, and enhances Li+ transport speed, and assists in the integration of cathode-electrolyte electrodes for room temperature solid-state batteries. The tough dual-channel Li+ transport electrolyte (TDCT) with Li-NC and polyvinylidene fluoride (PVDF) demonstrates a high Li+ transfer number (0.79) due to the synergistic coordination mechanism in Li+ transport. Integrated electrodes' design enables stable performance in LiNi0.5Co0.2Mn0.3O2|Li cells, with 720 cycles at 0.5 C, and 88.8% capacity retention. Furthermore, the lifespan of Li|TDCT|Li cells over 4000 h and Li-rich Li1.2Ni0.13Co0.13Mn0.54O2|Li cells exhibits excellent performance, proving the practical application potential of soft filler for high energy density solid-state lithium-metal batteries at room temperature.

Decoupling of ion-transport from polymer segmental relaxation and higher ionic-conductivity in poly(ethylene oxide)/succinonitrile composite-based electrolytes having low lithium salt doping

Only limited enhancement in room-temperature ionic-conductivity for poly(ethylene oxide), PEO, based electrolytes is possible due to coupling between ionic-conductivity and segmental relaxation. In the present study, we have achieved ionic-conductivity of 1.07 × 10-3 and 6.20 × 10-4 S cm-1 at 313 and 298 K, respectively, by adding 45 wt% of succinonitrile (SN) in PEO having low LiTFSI loading (Li : EO = 1 : 20). This enhancement in the ionic-conductivity is attributed to faster ion transport (diffusion coefficient, D = 3.63 × 10-5 cm2 s-1) occurring through the ion-transport channels as confirmed by positron annihilation lifetime spectroscopy. The ionic-transport through these channels is observed to be highly decoupled from the segmental relaxations as confirmed using broadband dielectric spectroscopy through Ratner's approach. The observed decoupling of ionic-conductivity from PEO segmental relaxation in PEO-SN composite-based electrolytes would be useful to design rather inexpensive all solid-state polymer electrolytes for Li ion batteries.

Advances in All-Solid-State Lithium-Sulfur Batteries for Commercialization

Solid-state batteries are commonly acknowledged as the forthcoming evolution in energy storage technologies. Recent development progress for these rechargeable batteries has notably accelerated their trajectory toward achieving commercial feasibility. In particular, all-solid-state lithium-sulfur batteries (ASSLSBs) that rely on lithium-sulfur reversible redox processes exhibit immense potential as an energy storage system, surpassing conventional lithium-ion batteries. This can be attributed predominantly to their exceptional energy density, extended operational lifespan, and heightened safety attributes. Despite these advantages, the adoption of ASSLSBs in the commercial sector has been sluggish. To expedite research and development in this particular area, this article provides a thorough review of the current state of ASSLSBs. We delve into an in-depth analysis of the rationale behind transitioning to ASSLSBs, explore the fundamental scientific principles involved, and provide a comprehensive evaluation of the main challenges faced by ASSLSBs. We suggest that future research in this field should prioritize plummeting the presence of inactive substances, adopting electrodes with optimum performance, minimizing interfacial resistance, and designing a scalable fabrication approach to facilitate the commercialization of ASSLSBs.

Insight into Multiple Intermolecular Coordination of Composite Solid Electrolytes via Cryo-Electron Microscopy for High-Voltage All-Solid-State Lithium Metal Batteries

Polymer/ceramic-based composite solid electrolytes (CSE) are promising candidates for all-solid-state lithium metal batteries (SLBs), benefiting from the combined mechanical robustness of polymeric electrolytes and the high ionic conductivity of ceramic electrolytes. However, the interfacial instability and poorly understood interphases of CSE hinder their application in high-voltage SLBs. Herein, a simple but effective CSE that stabilizes high-voltage SLBs by forming multiple intermolecular coordination interactions between polyester and ceramic electrolytes is discovered. The multiple coordination between the carbonyl groups in poly(ε-caprolactone) and the fluorosulfonyl groups in anions with Li6.5 La3 Zr1.5 Ta0.5 O12 nanoparticles is directly visualized by cryogenic transmission electron microscopy and further confirmed by theoretical calculation. Importantly, the multiple coordination in CSE not only prevents the continuous decomposition of polymer skeleton by shielding the vulnerable carbonyl sites but also establishes stable inorganic-rich interphases through preferential decomposition of anions. The stable CSE and its inorganic-rich interphases enable Li||Li symmetric cells with an exceptional lifespan of over 4800 h without dendritic shorting at 0.1 mA cm-2 . Moreover, the high-voltage SLB with LiNi0.5 Co0.2 Mn0.3 O2 cathode displays excellent cycling stability over 1100 cycles at a 1C charge/discharge rate. This work reveals the underlying mechanism behind the excellent stability of coordinating composite electrolytes and interfaces in high-voltage SLBs.

Construction of Janus structures on thin silk fabrics via misting for wet-thermal comfort and antimicrobial activity

Owing to their small fiber diameter (10-15 μm), silk fabrics are always thin (32-90 g m-2). Therefore, construction of the Janus surfaces of silk fabrics that possess excellent multifunctionality remains a formidable challenge. Herein, first, silk fabrics were grafted using glycidyltrimethylammonium chloride to form a superhydrophilic surface (G-side). Then, a unilateral hydrophobic surface (O-side) was readily fabricated by mist coating octadecyltrichlorosilane-functionalized SiO2 nanoparticles (NPs) to produce hierarchical surface textures. To prevent NP penetration from the G-side to the O-side, a "fireproof isolation" method was employed. Consequently, Janus silk fabrics (JanSFs) bearing asymmetric wettability were prepared, and their wetting gradient could be conveniently regulated. With the mist time ranging from 4 to 7 min, the unidirectional transport index and efficiency of the unidirectional water transport increased and decreased by 13.2 and 10.4 times, respectively. Sweat could be effectively drained away from human skin to ensure that the skin was dry and comfortable. Compared with the surface temperature of the raw fabric, the raw fabric of JanSFs increased by 2.7 °C. Furthermore, the breathability of JanSF was negligibly affected, and the outer O-side of the JanSF showed substantial antibacterial activity. This study is important for designing JanSFs that exhibit unidirectional water transport.

Phenylboronic Acid Functionalized Calix[4]pyrrole-Based Solid-State Supramolecular Electrolyte

Solid-state polymer electrolytes (SPEs) suffer from the low ionic conductivity and poor capability of suppressing lithium (Li) dendrites, which limits their utility in the preparation of all solid-state Li-metal batteries (LMBs). It is reported here a flexible solid supramolecular electrolyte that incorporates a new anion capture agent, namely a phenylboronic acid functionalized calix[4]pyrrole (C4P), into a poly(ethylene oxide) (PEO) matrix. The resulting solid-state supramolecular electrolyte demonstrates high ionic conductivity (1.9 × 10-3  S cm-1 at 60 °C) and a high Li+ transference number (t Li + ${t}_{{\mathrm{Li}}^{\mathrm{ + }}}$  = 0.70). Furthermore, the assembled Li|C4P-PEO-LiTFSI|LiFePO4 cell allows for stable cycling over 1200 cycles at 1 C at 60 °C, as well as good rate performance. The favorable performance of the C4P-PEO-LiTFSI SPE leads to suggest it can prove useful in the creation of high energy density solid-state LMBs.

Click Chemistry in Lithium-Metal Batteries

Lithium-metal batteries (LMBs) are considered the "holy grail" of the next-generation energy storage systems, and solid-state electrolytes (SSEs) are a kind of critical component assembled in LMBs. However, as one of the most important branches of SSEs, polymer-based electrolytes (PEs) possess several native drawbacks including insufficient ionic conductivity and so on. Click chemistry is a simple, efficient, regioselective, and stereoselective synthesis method, which can be used not only for preparing PEs with outstanding physical and chemical performances, but also for optimizing the stability of solid electrolyte interphase (SEI) layer and elevate the cycling properties of LMBs effectively. Here it is primarily focused on evaluating the merits of click chemistry, summarizing its existing challenges and outlining its increasing role for the designing and fabrication of advanced PEs. The fundamental requirements for reconstructing artificial SEI layer through click chemistry are also summarized, with the aim to offer a thorough comprehension and provide a strategic guidance for exploring the potentials of click chemistry in the field of LMBs.

Interconnected Three-Dimensional Porous Alginate-Based Gel Electrolytes for Lithium Metal Batteries

Lithium batteries have been widely used in our daily lives for their high energy density and long-term stability. However, their safety problems are of paramount concern for consumers, which restricts their scale applications. Gel polymer electrolytes (GPEs) compensate for the defects of liquid leakage and lower ionic conductivity of solid electrolytes, which have attracted a lot of attention. Herein, a 3D interconnected highly porous structural gel electrolyte was prepared with alginate dressing as a host material, poly(ethylene oxide) (PEO), and a commercial liquid electrolyte. With rich polar functional groups and (CH2-CH2-O) segments on the polymer matrix, the transportation of Li+ is faster and uniform; thus, the formations of lithium dendrite were significantly inhibited. The cycle stability of symmetrical Li||Li batteries with modified composite electrolytes (SAA) is greatly improved, and the overpotential remains stable after more than 1000 h. Meanwhile, under the same conditions, the cycle performance of batteries with unmodified electrolytes is inferior and overpotentials are nearly 1 V after 100 h. Additionally, the capacity retention of Li||LiFePO4 with SAA is more than 95% after 200 cycles, while those of the others declined sharply. The alginate dressing-based GPEs can greatly enhance the mechanical and thermal stability of PEO-based GPEs, which provides an environmentally friendly avenue for gel electrolytes' applications in lithium batteries.

Polydopamine-Induced Metal-Organic Framework Network-Enhanced High-Performance Composite Solid-State Electrolytes for Dendrite-Free Lithium Metal Batteries

Due to the high safety, flexibility, and excellent compatibility with lithium metals, composite solid-state electrolytes (CSEs) are the best candidates for next-generation lithium metal batteries, and the construction of fast and uniform Li+ transport is a critical part of the development of CSEs. In this paper, a stable three-dimensional metal-organic framework (MOF) network was obtained using polydopamine as a medium, and a high-performance CSE reinforced by the three-dimensional MOF network was constructed, which not only provides a continuous channel for Li+ transport but also restricts large anions and releases more mobile Li+ through a Lewis acid-base interaction. This strategy endows our CSEs with an ionic conductivity (7.1 × 10-4 S cm-1 at 60 °C), a wide electrochemical window (5.0 V), and a higher Li+ transfer number (0.54). At the same time, the lithium symmetric batteries can be stably cycled for 2000 h at 0.1 mA cm-2, exhibiting excellent electrochemical stability. The LiFePO4/Li cells have a high initial discharge specific capacity of 153.9 mAh g-1 at 1C, with a capacity retention of 80% after 915 cycles. This paper proposes an approach for constructing three-dimensional MOF network-enhanced CSEs, which provides insights into the design and development of MOFs for the positive effects of high-performance CSEs.

Anionic Anchoring Enhanced Quasi Solid Composite Polymer Electrolytes for High Performance Lithium Metal Battery

Herein, ZIF-8 inorganic particles with different sized reinforced poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) solid composite polymer electrolytes (PVDF-HFP/10%ZIF-8) were prepared via a facile blade-coating approach, and free-standing quasi solid-state composite electrolytes (PVDF-HFP/10%ZIF-8(0.6)/Plasticizer, abbreviated as PH/10%ZIF-8(0.6)/P), were further obtained through the introduction of plasticizer. Optimized PH/10%ZIF-8(0.6)/P exhibited a high ionic conductivity of 2.8 × 10-4 S cm-1 at 30 °C, and superior Li+ transfer number of 0.89 with an ultrathin thickness (26 µm). Therefore, PH/10%ZIF-8(0.6)/P could effectively inhibit the growth of lithium dendrites, and the assembled Li/LiFePO4 cell delivered good cycling stability with a capacity retention rate of 89.1% after 100 cycles at 0.5 C.

Poly-1,3-dioxolane anchoring graphitic carbon nitride to achieve high-energy-density solid-state Li metal batteries

Solid-state Li metal batteries (SSLMBs) are promising solutions for the next-generation energy storage devices with high energy densities and safety. Accordingly, the advanced solid-state electrolytes are further needed to address the challenges-low ionic conductivity, poor interfacial compatibility and uncontrollably Li dendrites, boosting the electrochemical and safety performances of SSLMBs. Herein, a "flexible and rigid" strategy is proposed to enhance the electrochemical and mechanical properties of polyethylene oxide (PEO)-based electrolytes. Specifically, the flexible poly-1,3-dioxolane (poly-DOL) and rigid graphitic carbon nitride (g-C3N4) are coordinated by a coupling reaction to prepare g-C3N4-poly-DOL, which is further employed as the filler for the PEO matrix to fabricate a composite polymer electrolyte g-C3N4-pDOL-PEO. The flexible poly-DOL and rigid g-C3N4 together endow the PEO-based electrolyte with good interfacial stability, high ion-conductivity and strong mechanical strength. Consequently, the Li/g-C3N4-pDOL-PEO/LiFePO4 cell delivers high cyclability with a capacity retention ratio of 89.7 % after 150 cycles and an average Coulombic efficiency over 99.9 %, and, the Li/g-C3N4-pDOL-PEO/Li cell can stably cycle beyond 300 h at 0.2 mAh cm-2 with small polarization (13 mV). The "flexible and rigid" strategy coupling the polymer with the filler provides an effective electrolyte design for high-performance SSLMBs.

Embedding of Laser Generated TiO2 in Poly(ethylene oxide) with Boosted Li+ Conduction for Solid-State Lithium Metal Batteries

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes are considered promising materials for realizing high-safety and high-energy-density lithium metal batteries. However, the high crystallinity of PEO at room temperature triggers low ionic conductivity and Li+ transference number, critically hindering practical applications in solid-state lithium metal batteries. Herein, we prepared nanosized TiO2 with enriched oxygen vacancies down to 13 nm as fillers by laser irradiation, which can be coated by in situ generated polyacetonitrile, ensuring good dispersibility in PEO. The electrolytes with nanosized TiO2 show a combination of high ionic conductivity, high Li+ transference number, superior electrochemical stability, and enhanced mechanical robustness. Accordingly, the lithium symmetric batteries with nanosized TiO2 composite solid electrolytes exhibit a stable cycling life up to 590 h at 0.25 mA cm-2. The full Li metal batteries paired with a LiFePO4 cathode deliver superior durability for 550 cycles. Moreover, the proof-of-concept pouch cells demonstrate excellent safety performance under various harsh conditions. This work provides a realistic guide in designing novel fillers to achieve stable operation of high-safety and energy-dense solid-state lithium metal batteries.

One Stone, Three Birds: An Air and Interface Stable Argyrodite Solid Electrolyte with Multifunctional Nanoshells

Li6 PS5 Cl (LPSC) solid electrolytes, based on Argyrodite, have shown potential for developing high energy density and safe all-solid-state lithium metal batteries. However, challenges such as interfacial reactions, uneven Li deposition, and air instability remain unresolved. To address these issues, a simple and effective approach is proposed to design and prepare a solid electrolyte with unique structural features: Li6 PS4 Cl0.75 -OF0.25 (LPSC-OF0.25 ) with protective LiF@Li2 O nanoshells and F and O-rich internal units. The LPSC-OF0.25 electrolyte exhibits high ionic conductivity and the capability of "killing three birds with one stone" by improving the moist air tolerance, as well as the interface compatibility between the anode or cathode and the solid electrolyte. The improved performance is attributed to the peculiar morphology and the self-generating and self-healing interface coupling capability. When coupled with bare LiCoO2 , the LPSC-OF0.25 electrolyte enables stable operation under high cutoff voltage (≈4.65 V vs Li/Li+ ), thick cathodes (25 mg cm-2 ), and large current density (800 cycles at 2 mA cm-2 ). This rationally designed solid electrolyte offers promising prospects for solid-state batteries with high energy and power density for future long-range electric vehicles and aircrafts.

Monodispersed Sub-1 nm Inorganic Cluster Chains in Polymers for Solid Electrolytes with Enhanced Li-Ion Transport

The organic-inorganic interfaces can enhance Li+ transport in composite solid-state electrolytes (CSEs) due to the strong interface interactions. However, Li+ non-conductive areas in CSEs with inert fillers will hinder the construction of efficient Li+ transport channels. Herein, CSEs with fully active Li+ conductive networks are proposed to improve Li+ transport by composing sub-1 nm inorganic cluster chains and organic polymer chains. The inorganic cluster chains are monodispersed in polymer matrix by a brief mixed-solvent strategy, their sub-1 nm diameter and ultrafine dispersion state eliminate Li+ non-conductive areas in the interior of inert fillers and filler-agglomeration, respectively, providing rich surface areas for interface interactions. Therefore, the 3D networks connected by the monodispersed cluster chains finally construct homogeneous, large-scale, continuous Li+ fast transport channels. Furthermore, a conjecture about 1D oriented distribution of organic polymer chains along the inorganic cluster chains is proposed to optimize Li+ pathways. Consequently, the as-obtained CSEs possess high ionic conductivity at room temperature (0.52 mS cm-1 ), high Li+ transference number (0.62), and more mobile Li+ (50.7%). The assembled LiFePO4 /Li cell delivers excellent stability of 1000 cycles at 0.5 C and 700 cycles at 1 C. This research provides a new strategy for enhancing Li+ transport by efficient interfaces.

Inhibited Grain Growth Through Phase Transition Modulation Enables Excellent Mechanical Properties in Oxide Ceramic Nanofibers up to 1700 °C

Oxide ceramics are widely used as thermal protection materials due to their excellent structural properties and earth abundance. However, in extremely high-temperature environments (above 1500 °C), the explosive growth of grain size causes irreversible damage to the microstructure of oxide ceramics, thus exhibiting poor thermomechanical stability. This problem, which may lead to catastrophic accidents, remains a great challenge for oxide ceramic materials. Here, a novel strategy of phase transition modulation is proposed to control the grain growth at high temperatures in oxide ceramic nanofibers, realizing effective regulation of the crystalline forms as well as the size uniformity of primary grains, and thus suppressing the malignant growth of the grains. The resulting oxide ceramic nanofibers have excellent mechanical strength and flexibility, delivering an average tensile strength as high as 1.02 GPa after being exposed to 1700 °C for 30 min, and can withstand thousands of flexural cycles without obvious damage. This work may provide new insight into the development of advanced oxide ceramic materials that can serve in extremely high-temperature environments with long-term durability.

Stabilizing Lithium Metal Batteries by Synergistic Effect of High Ionic Transfer Separator and Lithium-Boron Composite Material Anode

The development of lithium (Li) metal batteries (LMBs) has been limited by problems, such as severe dendrite growth, drastic interfacial reactions, and large volume change. Herein, an LMB (8AP@LiB) combining agraphene oxide-poly(ethylene oxide) (PEO) functionalized polypropylene separator (8AP) with a lithium-boron (LiB) anode is designed to overcome these problems. Raman results demonstrate that the PEO chain on 8AP can influence the Li+ solvation structure in the electrolyte, resulting in Li+ homogeneous diffusion and Li+ deposition barrier reduction. 8AP exhibits good ionic conductivity (4.9 × 10-4 S cm-1), a high Li+ migration number (0.88), and a significant electrolyte uptake (293%). The 3D LiB skeleton can significantly reduce the anode volume changes and local current density during the charging/discharging process. Therefore, 8AP@LiB effectively regulates the Li+ flux and promotes the uniform Li deposition without dendrites. The Li||Li symmetrical cells of 8AP@LiB exhibit a high electrochemical stability of up to 1000 h at 1 mA cm-2 and 5 mAh cm-2. Importantly, the Li||LiFePO4 full cells of 8AP@LiB achieve an impressive 2000 cycles at 2C, while maintaining a high-capacity retention of 86%. The synergistic effect of the functionalized separator and LiB anode might provide a direction for the development of high-performance LMBs.

An H2 O-Initiated Crosslinking Strategy for Ultrafine-Nanoclusters-Reinforced High-Toughness Polymer-In-Plasticizer Solid Electrolyte

Incorporating plasticizers is an effective way to facilitate conduction of ions in solid polymer electrolytes (SPEs). However, this conductivity enhancement often comes at the cost of reduced mechanical properties, which can make the electrolyte membrane more difficult to process and increase safety hazards. Here, a novel crosslinking strategy, wherein metal-alkoxy-terminated polymers can be crosslinked by precisely controlling the content of H2 O as an initiator, is proposed. As a proof-of-concept, trimethylaluminum (TMA)-functionalized poly(ethylene oxide) (PEO) is used to demonstrate that ultrafine Al-O nanoclusters can serve as nodes to crosslink PEO chains with a wide range of molecular weights from 10 000 to 8 000 000 g mol-1 . The crosslinked polymer network can incorporate a high concentration of plasticizers, with a total weight percentage over 75%, while still maintaining excellent stretchability (4640%) and toughness (3.87 × 104  kJ m-3 ). The resulting electrolyte demonstrates high ionic conductivity (1.41 mS cm-1 ), low interfacial resistance toward Li metal (48.1 Ω cm2 ), and a wide electrochemical window (>4.8 V vs Li+ /Li) at 30 °C. Furthermore, the LiFePO4 /Li battery shows stable cycle performance with a capacity retention of 98.6% (146.3 mAh g-1 ) over 1000 cycles at 1C (1C = 170 mAh g-1 ) at 30 °C.

A liquid metal-fluoropolymer artificial protective film enables robust lithium metal batteries at sub-zero temperatures

Batteries that are both high-energy-density and durable at sub-zero temperatures are highly desirable for deep space and subsea exploration and military defense applications. Our design incorporates a casting membrane technology to prepare a gallium indium liquid metal (LM)/fluoropolymer hybrid protective film on a lithium metal anode. The LM not only spontaneously forms a passivation alloy layer with lithium but also reduces the nucleation potential barrier and homogenizes the Li+ flux on the surface of the lithium anode. The fluoropolymer's polar functional groups (-C-F-) effectively induce targeted dispersion of gallium indium seeds, and the unique pit structure on the surface provides oriented sites for lithium plating. By implementing these strategies optimally, the protected lithium metal anode remains in operation at a current density of 20 mA cm-2 with an over-potential of about 50.4 mV after 500 h, and the full cells have a high capacity retention rate of up to 98.5% at a current density of 0.5 C after 100 cycles. Furthermore, the battery shows improved low temperature performance at -30 °C, validating the potential of the protective film to enable battery operation at sub-zero temperatures.

Titanium-Oxygen Clusters Brazing Li with Li6.5La3Zr1.5Ta0.5O12 for High-Performance All-Solid-State Li Batteries

Garnet-based solid-state electrolytes are considered crucial candidates for solid-state Li batteries due to their high Li+ conductivity and nonflammability; however, poor interfacial contact with the Li anode and growth of Li dendrites limit their application. Herein, a high-activity titanium-oxygen cluster is used as a brazing filler to braze the Li6.5La3Zr1.5Ta0.5O12 (LLZTO) with an Li anode into the whole unit. The brazing layer leads to a significantly lower interfacial impedance of 8.32 Ω cm2. Furthermore, the brazing layer is an isotropic amorphous ion-electron hybrid conductive layer, which significantly promotes Li+ transport and regulates the distribution of the electric field, therefore inhibiting the growth of Li dendrites. The cell exhibits an ultrahigh critical current density of 2.3 mA cm-2 and stable cycling of over 4000 h at 0.5 mA cm-2 (25 °C).

Improving Room-Temperature Li-Metal Battery Performance by In Situ Creation of Fast Li+ Transport Pathways in a Polymer-Ceramic Electrolyte

Composite polymer-ceramic electrolytes have shown considerable potential for high-energy-density Li-metal batteries as they combine the benefits of both polymers and ceramics. However, low ionic conductivity and poor contact with electrodes limit their practical usage. In this study, a highly conductive and stable composite electrolyte with a high ceramic loading is developed for high-energy-density Li-metal batteries. The electrolyte, produced through in situ polymerization and composed of a polymer called poly-1,3-dioxolane in a poly(vinylidene fluoride)/ceramic matrix, exhibits excellent room-temperature ionic conductivity of 1.2 mS cm-1 and high stability with Li metal over 1500 h. When tested in a Li|electrolyte|LiFePO4 battery, the electrolyte delivers excellent cycling performance and rate capability at room temperature, with a discharge capacity of 137 mAh g-1 over 500 cycles at 1 C. Furthermore, the electrolyte not only exhibits a high Li+ transference number of 0.76 but also significantly lowers contact resistance (from 157.8 to 2.1 Ω) relative to electrodes. When used in a battery with a high-voltage LiNi0.8 Mn0.1 Co0.1 O2 cathode, a discharge capacity of 140 mAh g-1 is achieved. These results show the potential of composite polymer-ceramic electrolytes in room-temperature solid-state Li-metal batteries and provide a strategy for designing highly conductive polymer-in-ceramic electrolytes with electrode-compatible interfaces.

A Three-Dimensional Fiber-Network-Reinforced Composite Solid-State Electrolyte from Waste Acrylic Fibers for Flexible All-Solid-State Lithium Metal Batteries

The large amount of waste chemical fiber textiles that exists has posed pressure on the sustainable development of the natural environment and of society. Therefore, it is of great importance to increase the added value of waste chemical fiber textiles and expand their applications in other fields. Herein, acrylic yarn from waste clothing is used as the raw material to construct a three-dimensional (3D) acrylic-based ceramic composite nanofiber solid electrolyte. The electrochemical properties of batteries based on this solid electrolyte are also investigated. We found that the fabricated composite electrolyte has good performance in lithium ion conduction and electrochemical stability because of its 3D acrylic-based ceramic composite fiber framework. The introduction of this composite electrolyte to a lithium symmetric battery enabled the battery to circulate stably for 2350 h at 50 °C without short-circuiting. In addition, all-solid-state batteries using a LiFePO4 cathode exhibited high reversible capacity. Lastly, a flexible lithium metal pouch battery was able to operate safely and stably under extreme conditions. This work demonstrates a strategy for upcycling waste textiles into ion-conducting polymers for energy storage applications.

Laponite-Supported Gel Polymer Electrolyte with Multiple Lithium-Ion Transport Channels for Stable Lithium Metal Batteries

Lithium metal batteries have emerged as a promising candidate for next-generation power systems. However, the high reactivity of lithium metal with liquid electrolytes has resulted in decreased battery safety and stability, which poses a significant challenge. Herein, we present a modified laponite-supported gel polymer electrolyte (LAP@PDOL GPE) that was fabricated using in situ polymerization initiated by a redox-initiating system at ambient temperature. The LAP@PDOL GPE effectively facilitates the dissociation of lithium salts via electrostatic interaction and simultaneously constructs multiple lithium-ion transport channels within the gel polymer network. This hierarchical GPE demonstrates a remarkable ionic conductivity of 5.16 × 10^-4 S cm^-1 at 30 °C. Furthermore, the robust laponite component of the LAP@PDOL GPE forms a barrier against Li dendrite growth while also participating in the establishment of a stable electrode/electrolyte interface with Si-rich components. The in situ polymerization process further improves the interfacial contact, enabling the LiFePO₄/LAP@PDOL GPE/Li cell to exhibit an impressive capacity of 137 mAh g^-1 at 1C, with a capacity retention of 98.5% even after 400 cycles. In summary, the developed LAP@PDOL GPE shows great potential in addressing the critical issues of safety and stability associated with lithium metal batteries while also delivering improved electrochemical performance.

Chemically bonding inorganic fillers with polymer to achieve ultra-stable solid-state sodium batteries

Inorganic/organic composite solid electrolytes (CSEs) have attracted ever-increasing attentions due to their outstanding mechanical stability and processibility. However, the inferior inorganic/organic interface compatibility limits their ionic conductivity and electrochemical stability, which hinders their application in solid-state batteries. Herein, we report a homogeneously distributed inorganic fillers in polymer by in-situ anchoring SiO₂ particles in polyethylene oxide (PEO) matrix (I-PEO-SiO₂). Compared with ex-situ CSEs (E-PEO-SiO₂), SiO₂ particles and PEO chains in I-PEO-SiO₂ CSEs are closely welded by strong chemical bonds, thus addressing the issue of interfacial compatibility and realizing excellent dendrite-suppression ability. In addition, the Lewis acid-base interactions between SiO₂ and salts facilitate the dissociation of sodium salts and increase the concentration of free Na⁺. Consequently, the I-PEO-SiO₂ electrolyte demonstrates an improved Na⁺ conductivity (2.3 × 10^-4 S cm^-1 at 60 °C) and Na⁺ transference number (0.46). The as constructed Na₃V₂(PO₄)₃ ‖ I-PEO-SiO₂ ‖ Na full-cell demonstrates a high specific capacity of 90.5 mAh g^-1 at 3C and an ultra-long cycling stability (>4000 cycles at 1C), outperforming the state-of-the-art literatures. This work provides an effective way to solve the issue of interfacial compatibility, which can enlighten other CSEs to overcome their interior compatibility.

A Universal Room-Temperature 3D Printing Approach Towards porous MOF Based Dendrites Inhibition Hybrid Solid-State Electrolytes

Hybrid solid-state electrolytes (HSSEs) provide new opportunities and inspiration for the realization of safer, higher energy-density metal batteries. The innovative application of 3-dimensional printing in the electrochemical field, especially in solid-state electrolytes, endows energy storage devices with fascinating characteristics. In this paper, effective dendrite-inhibited PEO/MOFs HSSEs is innovatively developed through universal room-temperature 3-dimensional printing (RT-3DP) strategy. The prepared HSSEs display enhanced dendrite inhibition due to the porous MOF filler promoting homogeneity of lithium deposition and the formation of C-OCO₃ Li, ROLi, LiF mesophases, which further improve the migration of Li⁺ in PEO chain and comprehensive performances. This universal strategy realizes the fabrication of different slurry components (PEO with ZIF-67, MOF-74, UIO-66, ZIF-8 fillers) HSSEs at RT environment, providing new inspirations for the exploration of next-generation advanced solid-state batteries.

High-Voltage Solid-State Lithium Metal Batteries with Stable Anodic and Cathodic Interfaces by a Laminated Solid Polymer Electrolyte

Solid polymer electrolyte (SPE) is quite an attractive candidate for constructing high-voltage Li metal batteries (LMBs) with high energy density and excellent safety. However, sim ultaneous achievement of high-voltage stability against the cathode and good compatibility with the Li anode remains challenging for the current SPE technology. Herein, a dual-layered solid electrolyte (DLSE) consisting of an oxidation-resistant poly(acrylonitrile) (PAN) layer facing a high-potential cathode and a reduction-compatible poly(vinylidene fluoride) (PVDF) layer incorporated by Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZTO) nanoparticles and an ionic liquid plasticizer in contact with a Li anode was fabricated. The uniquely designed DLSE holds favorable overall properties in ionic conductivity, Li⁺ transference number, and mechanical strength. Moreover, the combined advantages of two polymer electrolyte layers greatly address the interface issues on both the cathode and anode. Consequently, the high-voltage LMBs employing the DLSE exhibit excellent room-temperature performances including high rate capacity and long cycle life.

Rational Design of High-Performance PEO/Ceramic Composite Solid Electrolytes for Lithium Metal Batteries

Composite solid electrolytes (CSEs) with poly(ethylene oxide) (PEO) have become fairly prevalent for fabricating high-performance solid-state lithium metal batteries due to their high Li+ solvating capability, flexible processability and low cost. However, unsatisfactory room-temperature ionic conductivity, weak interfacial compatibility and uncontrollable Li dendrite growth seriously hinder their progress. Enormous efforts have been devoted to combining PEO with ceramics either as fillers or major matrix with the rational design of two-phase architecture, spatial distribution and content, which is anticipated to hold the key to increasing ionic conductivity and resolving interfacial compatibility within CSEs and between CSEs/electrodes. Unfortunately, a comprehensive review exclusively discussing the design, preparation and application of PEO/ceramic-based CSEs is largely lacking, in spite of tremendous reviews dealing with a broad spectrum of polymers and ceramics. Consequently, this review targets recent advances in PEO/ceramic-based CSEs, starting with a brief introduction, followed by their ionic conduction mechanism, preparation methods, and then an emphasis on resolving ionic conductivity and interfacial compatibility. Afterward, their applications in solid-state lithium metal batteries with transition metal oxides and sulfur cathodes are summarized. Finally, a summary and outlook on existing challenges and future research directions are proposed.

Effect of LLZO on the in situ polymerization of acrylate solid-state electrolytes on cathodes

The comprehensive performance of the state-of-the-art solid-state electrolytes (SSEs) cannot match the requirements of commercial applications, and constructing an organic-inorganic composite electrolyte in situ on a porous electrode is an effective coping strategy. However, there are few studies focused on the influence of inorganic ceramics on the polymerization of multi-organic components. In this study, it was found that the addition of Li_6.4La₃Zr_1.4Ta_0.6O₁₂ (LLZO) weakens the interaction between different polymers and makes organic and inorganic components contact directly in the solid electrolyte. These suppress the segregation of components in the in situ polymerized composite SSE, leading to a decrease in the polymer crystallization and improvement of electrolyte properties such as electrochemical stability window and mechanical properties. The composite solid-state electrolyte can be in situ constructed on different porous electrodes, which can establish close contact with active material particles, showing an ionic conductivity 4.4 × 10^-5 S cm^-1 at 25 °C, and afford the ternary cathode stability for 100 cycles.

A room temperature rechargeable Li2O-based lithium-air battery enabled by a solid electrolyte

A lithium-air battery based on lithium oxide (Li₂O) formation can theoretically deliver an energy density that is comparable to that of gasoline. Lithium oxide formation involves a four-electron reaction that is more difficult to achieve than the one- and two-electron reaction processes that result in lithium superoxide (LiO₂) and lithium peroxide (Li₂O₂), respectively. By using a composite polymer electrolyte based on Li₁₀GeP₂S₁₂ nanoparticles embedded in a modified polyethylene oxide polymer matrix, we found that Li₂O is the main product in a room temperature solid-state lithium-air battery. The battery is rechargeable for 1000 cycles with a low polarization gap and can operate at high rates. The four-electron reaction is enabled by a mixed ion-electron-conducting discharge product and its interface with air.

Directional Ion Transport Enabled by Self-Luminous Framework for High-Performance Quasi-Solid-State Lithium Metal Batteries

Composite gel polymer electrolyte (CGPE), derived from ceramic fillers has emerged as one of the most promising candidates to improve the safety and cycling stability of lithium metal batteries. However, the poor interface compatibility between the ceramic phase and polymer phase in CGPE severely deteriorates lithium-ion pathways and cell performances. In this work, a fluorescent ceramic nanowire network that can palliate the energy barrier of photoinitiators and contribute to preferential nucleation and growth of polymer monomers is developed, thus inducing polymer segment orderly arrangement and tightly combination. A proof-of-concept study lies on fabrications of poly(ethylene oxide) closely coating on the ceramic nanowires, thus dividing the matrix into mesh units that contribute to directional lithium-ion flux and dendrite-free deposition on the metallic anode. The CGPE, based on the state-of-the-art self-luminous framework, facilitates high-performance quasi-solid-state Li||LiFePO₄ cell, registering a high capacity of 143.3 mAh g^-1 after 120 cycles at a mass loading of 12 mg cm^-2 . X-ray computed tomography provides an insight into the relationship between directional lithium-ion diffusion and lithium deposition behavior over the electrochemical processes. The results open a door to improve the electrochemical performances of composite electrolytes in various applications.

Negatively Charged Laponite Sheets Enhanced Solid Polymer Electrolytes for Long-Cycling Lithium-Metal Batteries

Solid polymer electrolytes suffer from the low ionic conductivity and poor capability of suppressing lithium dendrites, which have greatly hindered the practical application of solid-state lithium-metal batteries. Here, we report a novel laponite sheet (LS) with a large negatively charged surface as an additive in a solid composite electrolyte (poly(ethylene oxide)-LS) to rearrange the lithium-ion environment and enhance the mechanical strength of the electrolytes (PEO-LS). The strong electrostatic regulation of laponite sheets assists the dissociation of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and constructs multiple transport channels for free lithium ions, achieving a high ionic conductivity of 1.1 × 10^-3 S cm^-1 at 60 °C. Furthermore, LS facilitates the in situ formation of a LiF-rich interface because of the boosting TFSI^- anion concentration, which significantly suppresses lithium dendrites and prevents short circuit. As a result, the assembled LiFePO₄|PEO-LS|Li battery demonstrates a long cycle life of over 800 cycles and a high Coulombic efficiency of 99.9% at 1C and 60 °C. When paired with a high-voltage NCM811 cathode, the battery also demonstrates excellent cycling stability and rate capability.

Insight into the Key Factors in High Li+ Transference Number Composite Electrolytes for Solid Lithium Batteries

Solid lithium batteries (SLBs) have received much attention due to their potential to achieve secondary batteries with high energy density and high safety. The solid electrolyte (SE) is believed to be the essential material for SLBs. Among the recent SEs, composite electrolytes have good interfacial compatibility and customizability, which have been broadly investigated as promising contenders for commercial SLBs. The high Li⁺ transference number (t Li + ${{_{{\rm Li}{^{+}}}}}$ ) of composite electrolytes is critically important concerning the power/energy density and cycling life of SLBs, however, which is often overlooked. This Review presents a current opinion on the key factors in high t Li + ${{_{{\rm Li}{^{+}}}}}$ composite electrolytes, including polymers, Li-salts, inorganic fillers, and additives. Various strategies concerning providing a continuous pathway for Li-ions and immobilizing anions via component interaction are discussed. This Review highlights the major obstacles hindering the development of high t Li + ${{_{{\rm Li}{^{+}}}}}$ composite electrolytes and proposes future research directions for developing composite electrolytes with high t Li + ${{_{{\rm Li}{^{+}}}}}$ .

An Asymmetric Cross-Linked Ionic Copolymer Hybrid Solid Electrolyte with Super Stretchability for Lithium-Ion Batteries

Composite solid electrolytes are recommended to be the most promissing strategy for solid-state batteries because they combine the advantages of inorganic ceramics and polymers. However, the huge interfacial resistance between the inorganic ceramic and polymer results in low ionic conductivity, which is still the major impediment that limits their applications. Herein, a novel highly elastic and weakly coordinated ionic copolymer hybrid electrolyte with asymmetric structure based on surface-modified Li_1.5 Al_0.5 Ge_1.5 (PO₄ )₃ by "in situ" polymerization is proposed to improve ionic conductivity and mechanical properties simultaneously. The all-solid hybrids electrolytes exhibit room-temperature ionic conductivity up to 2.61 × 10^-4 S cm^-1 and lithium-ion transference number of 0.41. The hybrids electrolytes can be repeatedly stretching-releasing-stretching, showing a super stretchability with the elongation at break up to 496%. The Li symmetrical cells assembled with the hybrid electrolytes can continuously operate for 800 h at 0.1 mA cm^-2 without discernable dendrites, indicating good interfacial compatibility between the hybrid electrolytes and lithium electrodes. The Li|LiFePO₄ batteries assembled with the hybrid electrolytes deliver an initial discharge specific capacity of 165.5 mAh g^-1 with an initial coulombic efficiency of 94.8% and 154 mAh g^-1 after 100 cycles at 0.1 C, and maintain 95.4% capacity retention after 100 cycles at 0.5 C.

Filler-Integrated Composite Polymer Electrolyte for Solid-State Lithium Batteries

Composite polymer electrolytes (CPEs) utilizing fillers as the promoting component bridge the gap between solid polymer electrolytes and inorganic solid electrolytes. The integration of fillers into the polymer matrices is demonstrated as a prevailing strategy to enhance Li-ion transport and assist in constructing Li⁺ -conducting electrode-electrolyte interface layer, which addresses the two key barriers of solid-state lithium batteries (SSLBs): low ionic conductivity of electrolyte and high interfacial impedance. Recent review articles have largely focused on the performance of a broad spectrum of CPEs and the general effects of fillers on SSLBs device. Recognizing this, in this review, after briefly presenting the categories of fillers (traditional and emerged) and the promoted ionic conducting mechanisms in CPEs, the progress in the interfacial structure design principle, with the emphasis on the crucial influence of filler size, concentration, and hybridization strategies on filler-polymer interface that is the most critical to Li-ion transport is assessed. The latest exciting advances on filler-enabled in situ generation of a Li⁺ -conductive layer at the electrode-electrolyte interface to greatly reduce the interfacial impedance are further elaborated. Finally, this review discusses the challenges to be addressed, outlines research directions, and provides a future vision for developing advanced CPEs for high-performing SSLBs.