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Electrolytes with high stability against both Li anode and high‐voltage cathode are critical for high‐energy and long‐cycling lithium metal batteries (LMBs). However, the free active solvents in common electrolytes are susceptible to decomposition at both Li anode and high‐voltage cathode. Although recently developed locally high‐concentration electrolytes (LHCEs) have largely restricted active solvents via Li+ coordination, the free molecules are still released upon the desolvation of Li+ at the surface of electrodes, causing continuous decomposition during long‐cycling processes. Here, a molecule competitive solvation electrolyte (MCE) is shown to stabilize high‐voltage LMBs by introducing a well‐designed and newly synthetic bipolar solvent molecule with one ion‐dissociative polar head and the other highly fluorinated nonpolar tail. The bipolar molecules competitively dissociate Li+ via weak coordination interactions, drastically reducing the ratio of active solvents in electrolytes and the detrimental decomposition at electrodes during the desolvation processes. Consequently, the MCE enables a 1.4‐Ah Li metal pouch cell with a stack energy density of 450 Wh kg−1 along with exceptional operation stability over 400 cycles (retention: 81%). Furthermore, the MCE also maintains the stable operation of a 2.5‐Ah Li‐S pouch cell with an excellent energy density of 417 Wh kg−1 for 70 cycles under practical conditions. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) have received great attention as promising candidates for next-generation energy-storage systems due to their high theoretical energy density. However, their practical energy density is limited by a large electrolyte-to-sulfur (E/S) ratio (>10 µL electrolyte/mg s), and their cycle performance encounters challenges from electrode passivation and Li dendrite formation. In this work, a dual-functional electrolyte additive of tetraethylammonium nitrate (TEAN) is presented to address these issues. NO3− as a high-donor-number (DN) salt anion can promote polysulfide dissolution, increase sulfur utilization, and alleviate electrode passivation. The tetraethylammonium cation can adsorb around Li protrusions to form a lithiophobic protective layer to inhibit the formation of Li dendrites. TEAN LSBs show improving capacity, cycling stability, and higher coulombic efficiency under lean electrolyte (5 μL electrolyte/mg s) conditions. [ABSTRACT FROM AUTHOR]

All‐solid‐state lithium batteries (ASSBs) enabled by solid‐state electrolytes (SEs) including oxide‐based and sulfide‐based electrolytes have gained worldwide attention because of their intrinsic safety and higher energy density over conventional lithium‐ion batteries (LIBs). However, despite the high ionic conductivity of advanced SEs, ASSBs still exhibit high overall internal resistance, the most significant contributor of which can be ascribed to the cathode‐SE interfaces. This review seeks to clarify the critical issues regarding the cathode‐SE interfaces, including fundamental principles and corresponding solutions. First, major issues concerning electro‐chemo‐mechanical instability between cathodes and SEs and their formation mechanisms are discussed. Then, specific problems in oxides and sulfides and various solutions and strategies toward interfacial modifications are highlighted. Efforts toward the characterization and analysis of cathode‐SE interfaces with advanced techniques are also summarized. Finally, perspectives are offered on several problems demanding urgent solutions and the future development of SE applications and ASSBs. [ABSTRACT FROM AUTHOR]

The electrochemical stability window of the electrolyte solution limits the energy content of non-aqueous lithium metal batteries. In particular, although electrolytes comprising fluorinated solvents show good oxidation stability against high-voltage positive electrode active materials such as LiNi0.8Co0.1Mn0.1O2 (NCM811), the ionic conductivity is adversely affected and, thus, the battery cycling performance at high current rates and low temperatures. To address these issues, here we report the design and synthesis of a monofluoride ether as an electrolyte solvent with Li-F and Li-O tridentate coordination chemistries. The monofluoro substituent (-CH2F) in the solvent molecule, differently from the difluoro (-CHF2) and trifluoro (-CF3) counterparts, improves the electrolyte ionic conductivity without narrowing the oxidation stability. Indeed, the electrolyte solution with the monofluoride ether solvent demonstrates good compatibility with positive and negative electrodes in a wide range of temperatures (i.e., from −60 °C to +60 °C) and at high charge/discharge rates (e.g., at 17.5 mA cm−2). Using this electrolyte solution, we assemble and test a 320 mAh Li||NCM811 multi-layer pouch cell, which delivers a specific energy of 426 Wh kg−1 (based on the weight of the entire cell) and capacity retention of 80% after 200 cycles at 0.8/8 mA cm−2 charge/discharge rate and 30 °C. The energy content of non-aqueous lithium batteries is limited by the electrochemical stability window of the electrolyte solution. Here, the authors report a monofluoride ether-based electrolyte to stabilize high-voltage lithium metal batteries at high current rates and low temperatures. [ABSTRACT FROM AUTHOR]

As a promising candidate of current solid-state electrolytes with various advantages, such as broad electrochemical stability window, high thermal stability, and chemical stability, garnet-type solid-state electrolyte Li7La3Zr2O12 (LLZO) attracts extensive research attention. Researchers usually use the element doping method to improve the lithium ion conductivity of LLZO and to stabilize the cubic phase. However, the improvements either increase the cost of raw materials or need complex process. In this work, the preparation process of Al-doped LLZO is optimized by a simple post-doping method (LLZO-Al), and the as-prepared LLZO-Al shows a high lithium ion conductivity of 5.331 × 10−4 S cm−1 and an activation energy of 0.25 eV at room temperature. In addition, the LLZO-Al exhibits excellent stability against Li in LiǁLLZO-AlǁLi symmetric cell, and the LiNi0.8Co0.1Mn0.1O2 (NCM811)ǁLLZO-AlǁLi solid-state cell delivers a stable cycle of 120 cycles at 0.1C. This work offers a low-cost preparation method of LLZO-based solid-state electrolytes with high ionic conductivities for high-energy solid-state lithium metal batteries. [ABSTRACT FROM AUTHOR]

Solid polymer electrolyte with good thermal stability and flexibility is an excellent candidate for solid‐state lithium metal batteries, while its low ionic conductivity caused by high crystallinity limits its application at ambient temperature. Here a metal organic framework (zeolitic imidazolate framework‐8, ZIF‐8) composited comb‐like methoxy poly(ethylene glycol) acrylate polymer electrolyte (MCPE) with high ionic conductivity (9.96 × 10−5 S cm−1 at 30 °C) is prepared by an in situ UV polymerization method. The as‐prepared MCPE exhibits improved mechanical property due to the introduction of porous ZIF‐8 nanofillers, which is beneficial to suppress the growth of lithium dendrites. Consequently, the LiFePO4||MCPE||Li cells show a high capacity of 116 mAh g−1 at 30 °C and 0.5 C, and maintain 89.4% of initial capacity after 150 cycles with the average Coulombic efficiency of 99.9%. These results demonstrate that the MCPE shows great potential in solid‐state lithium metal batteries near room temperature. [ABSTRACT FROM AUTHOR]

Correction to: I Nature Communications i https://doi.org/10.1038/s41467-023-36793-6, published online 25 February 2023 Supplementary Figure 30 of this article contained an error. These authors contributed equally: Guangzhao Zhang, Jian Chang. [Extracted from the article]

Gel polymer electrolytes (GPEs) hold great promise for lithium (Li) metal batteries (LMBs). Nevertheless, a critical challenge lies in reducing the thickness of GPEs while maintaining their mechanical integrity to achieve high‐energy‐density LMBs. Additionally, protecting the Li metal anode via electrolyte engineering in GPEs remains demanding. Herein, an innovative ultrathin (1 µm‐thick) yet robust GPE developed using an in situ curing technique, featuring a nanofibrous, exceptionally strong polyethylene separator is presented. The unique microstructure, interfacial conformability, and ultrahigh mechanical robustness of the ultrathin polyethylene separator are thoroughly verified. Enhanced ionic association within the GPE is achieved due to the strong affinity of electrolyte solvent with the fluorinated polymer network, as confirmed by large‐scale molecular dynamics simulations. The optimized solvation structure with high contact ion pairs and aggregate fractions contributes to forming an anion‐derived inorganic‐rich solid electrolyte interphase (SEI), thereby protecting the lithium anode. Benefiting from the ultrahigh robustness of GPE and the excellent interfacial stability, the Li metal full cell with a high mass loading LiNi0.8Co0.1Mn0.1O2 cathode (≈17.3 mg cm−2) and thin Li foil anode (50 µm) demonstrates 91% capacity retention after 200 cycles. This design demonstrates a feasible approach toward the practical quasi‐solid‐state LMBs. [ABSTRACT FROM AUTHOR]

The PE separator modified by double-coated nano-sized LLZTO is developed. Benefiting from the double-coated nano-sized LLZTO layer's enhancement to thermal stability and it can guide the uniform deposition of lithium ions and suppress the growth of lithium dendrites, an excellent electrochemical performance could be achieved in the lithium symmetric cell and lithium metal batteries. [Display omitted] • The PE separator modified by double-coated nano-sized LLZTO is developed. • The nano-sized LLZTO improves the thermal stability of the PE separator. • It can also guide the uniform Li ions deposition and suppress Li dendrites lithium. • Symmetric and full cells with LLZTO-coated separator exihibit an excellent performance. Lithium metal batteries, as one of high-energy-density batteries, have become the hot spot for numerous researchers. However, serious safety problems caused by lithium dendrites need to be urgently addressed. In this work, we introduce nano-sized garnet solid-state electrolyte Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 (LLZTO) to fabricate a high-safety thin composite solid electrolyte membrane (20 μm) that is simple in process and facile in preparation conditions. The thin composite solid electrolyte film has better wrinkle resistance than ordinary polyethylene (PE) films and can guide the uniform deposition of lithium ions and suppress the growth of lithium dendrites. The thermal stability of the PE separator modified by double-coated nano-sized LLZTO is enhanced, which exhibits only 30 % shrinking percentage at 140 °C in comparison with 90 % of ordinary PE. The lithium symmetric cell with the nano-sized garnet solid-state electrolyte modified separator is relatively stable after 1000 h cycling at the current density of 1 mA cm−2. More importantly, after adding the adaptable electrolyte, the lithium metal battery assembled with modified separator can be maintained for 150 cycles (0.2C) stably with a high cathode active material loading of NCM811 (18 mg cm−2), and can maintain above 95 % Coulombic efficiency on average. Our work provides a pathway for the preparation of superior thermal stability and high safety garnet-based composite membranes towards lithium metal batteries. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) are considered to be next-generation high-energy-density storage devices because of the ultrahigh theoretical specific capacity and low reduction potential of the Li metal anode. The electroplating/stripping behavior of Li metal and the properties of the solid-electrolyte interphase (SEI) are key issues that must be well understood. Traditional structural investigations using electron microscopy can facilitate this understanding, but they lack three-dimensional information. Herein, the burgeoning technique, cryogenic electron tomography, is used in the study of LMBs to visualize the morphology of electrochemically deposited Li metal and the SEI in various electrolytes. High-aspect-ratio dendrites are formed in ethylene carbonate-diethyl carbonate (EC-DEC) and EC-DEC/vinylene carbonate electrolytes, whereas irregularly shaped Li metal is formed in an EC-DEC-fluoroethylene carbonate electrolyte. In contrast, the use of a 1,3-dioxolane-1,2-dimethoxyethane-LiNO 3 electrolyte produces spherical Li metal. Three-dimensional reconstructions of the Li dendrites formed after half-charging revealed polyhedral-shaped "dead Li" tightly wrapped by a folded SEI layer, indicating the mechanism of "dead Li" formation. The non-uniform stripping rate of Li and the elimination of electron conduction paths by the surrounding SEI husks lead to the formation of such "dead Li." • The Cryo-ET is expand in the research realm of Li metal batteries. • 3D structures of the electrochemically deposited Li and the SEI are visualized. • Sometimes, in DOL-DME LiNO 3 electrolyte system, Li strips ununiformly. • Ununiformly stripping Li and wrinkled SEI causes formations of dead Li. [ABSTRACT FROM AUTHOR]

Garnet-based all-solid-state lithium batteries are expected to achieve high energy density and safety. However, the distinctly different chemical and electrochemical environment between the electrodes and garnet-type Li 6·4 La 3 Zr 1·6 Ta 0·4 O 12 (LLZTO) electrolyte results in high interfacial impedance that greatly hinders the electrochemical performance. Herein, we propose an asymmetrical interface modification strategy by respectively introducing an ultrathin in-situ polymerized interlayer on the cathode side and a lithiophilic liquid metal coating layer on the Li metal anode side. As a result, the interfacial impedance on both side is significantly reduced to 214 Ω cm2 on the cathode side and 7.45 Ω cm2 on the Li metal anode side due to the intimate contact and enhanced wettability between Li metal and GSSE together with improved conformability on the cathode side and Li ion conductance within the cathode. Therefore, the interface modified LiFePO 4 ||LLZTO||Li all-solid-state battery exhibits excellent cycling performance over 150 cycles with capacity retention of 96.7% and small voltage polarization of 55 mV at 0.1C and 60 °C. This work provides a convenient strategy to alleviate the interfacial issues in all-solid-state batteries. • Asymmetrical modification layers are introduced between electrolyte and electrodes. • Low impedance of 213.9 Ω cm2 is achieved with in-situ polymerized interlayer. • Impedance of 7.45 Ω cm2 on anode side is realized with liquid metal coating layer. • LFP.||SPE@LLZTO@LM||Li battery has capacity retention of 96.7% after 150 cycles. • The battery also shows a small voltage polarization of 55 mV at 0.1C and 60 °C. [ABSTRACT FROM AUTHOR]

Garnet-based solid-state lithium (Li) metal batteries are regarded as one of the most promising high-energy-density and high-safety batteries because of the broad electrochemical stability window and high Li ion conductivity of garnet electrolytes, as well as their excellent chemical stability against Li metal. However, during the practical batteries cycling, it is found that Li dendrites grow in the interior of garnet, especially in the grain boundary, thus leading to the short circuit of the working batteries, which seriously hinders the application of garnet-based Li metal batteries. In this review, we summarize the Li dendrites growth mechanism, characterization techniques, and the interfacial issue of garnet-based solid-state Li metal batteries. Meanwhile, the strategies for regulating Li dendrites growth are also analyzed. In addition, the further perspective and some suggestions are proposed to develop garnet-based solid-state Li metal batteries. This review tends to show fresh views on the understanding of Li dendrites growth mechanism in garnet electrolytes and the rational design of interfacial layer for regulating dendrites and manufacturing the batteries when pairing with Li metal anode. [Display omitted] • The lithium dendrites growth mechanism in garnet is systematically analyzed. • The strategies for regulating lithium dendrites growth are also be summarized. • High electronic conductivity of garnet induces dendritic lithium growth. • Lithium dendrites grow mainly along the interior, especially in the grain boundary. • Building interfacial layer on garnet effectively regulates lithium dendrites growth. [ABSTRACT FROM AUTHOR]

• Water-based phytic acid-crosslinked supramolecular binders were prepared. • The binder was used for high-energy-density lithium-sulfur batteries. • Three-dimensional porous carbon was used as sulfur hosts. • The high discharge capacity was achieved at a high sulfur loading. Rechargeable Li-S batteries have drawn much attention because of their high theoretical energy density (2600 Wh kg−1) and environmental friendliness. However, Li-S batteries undergo complex phase transitions and large volume changes during the charge-discharge process, which greatly decreases the lifetimes of Li-S batteries. Here, we investigate the use of water-based phytic acid-crosslinked supramolecular binders in the sulfur cathode to prolong charge-discharge cycling of Li-S batteries. The supramolecular binder is fabricated with a mixture of phosphorylated soybean protein isolate (P-SPI), poly(ethylene oxide) (PEO), and phytic acid (PA), which is denoted by SPP. Strong adsorption of polysulfides by the SPP binder is verified by using UV–vis spectroscopy with an in situ battery. In the sulfur cathodes, the three-dimensional carbon (3DC) with the specific surface area of 2208 m2/g and the total pore volume of 1.64 cm3/g is used as sulfur hosts. The high discharge capacity of 932.8 mAh g−1 is achieved by SPP-based Li-S batteries at a high sulfur loading of 8.9 mg cm−2 at 0.1C. A discharge capacity at 1C is 629.7 mAh g−1, with stable cycling over 800 charge-discharge cycles, and a capacity attenuation of only 0.0298% per cycle. The coulombic efficiency remained at 99.7%. The new type of water-based supramolecular polymer binder has high potential for use in high-energy-density Li-S batteries. [ABSTRACT FROM AUTHOR]

Constructing a stable microstructure is highly crucial in promoting the practical applications of Si-based negative electrodes, addressing the issues of huge volume change and unstable solid electrolyte interface (SEI). Herein, an integrated electrode structure is developed based on micro-sized SiO x particles by bilayers coating of carbon and poly(3,4-ethylene dioxythiophene) (PEDOT) with carbon nanotube/Super P conductive network in-situ embedded (SiO x @C@P_CS). The as-prepared SiO x @C@P_CS negative electrode exhibits high Coulombic efficiency reaching 99.9% and capacity retentions of 86.7% (1019 mAh g−1) after 1000 cycles at 750 mA g−1 and 98.4% (973 mAh g−1) after 400 cycles at 1500 mA g−1 (with a commercial-level areal capacity of 2.57 mAh cm−2). The excellent long cycling capability is further evidenced both in half cell with ultrahigh areal capacity up to 11.75 mAh cm−2 at the mass loading of 8.66 mg cm−2 and Li[Ni 0.8 Co 0.1 Mn 0.1 O 2 (NCM811)||SiO x @C@P_CS full cell with commercial loading. The improved electrochemical performance is attributed to the synergistic effects of the bilayers. This study offers a facile solution to the challenges facing alloying-type negative electrode materials with huge volume changes by confining volume change, enhancing electric conductivity, and isolating the growth of SEI to promote their practical uses. Image 1 • An integrated electrode structure is developed based on micro-sized SiO x particles. • The inner layer is carbon for the bilayers coating of SiO x. • The outer layer is poly(3,4-ethylene dioxythiophene) with conductive network. • Superior electrochemical performance of the bilayers coated SiO x is achieved. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPEs) shows increasing promise for all-solid-state batteries due to their high safety, high flexibility and low interfacial resistance. However, the low ionic conductivity at room temperature is the main barrier hindering the practical application of SPEs. Herein, hollow nanotubular clay composited comb-like methoxy poly(ethylene glycol) acrylate polymer electrolyte (HCPE) is fabricated by in-situ UV activated radical polymerization, which exhibits an improved ionic conductivity of 5.62 × 10−5 S cm−1 at room temperature. The introducing of the branched structure helps reduce the regularity of polymer chains and decreases the proportion of crystalline regions of polymers. Moreover, the nanofiller feature and the special structure of halloysite nanotube (HNT) are beneficial for dissociating lithium salt, thus improving the ionic conductivity. Meanwhile, the designed composite solid-state electrolyte demonstrates high thermal stability and compatibility with Li metal, high electrochemical stability. The all-solid-state Li/HCPE/LiFePO 4 cell delivers high rate capability and stable cycling performance at room temperature, which proves the great potential of HCPE for all-solid-state Li metal batteries. • A hollow nanotubular clay composited comb polymer is prepared. • The solid polymer electrolyte shows high conductivity and good thermal stability. • The solid polymer electrolyte exhibits broad electrochemical stability window. • The solid-state cell delivers high rate capability and good cycling performance. [ABSTRACT FROM AUTHOR]