Hybrid Solid-state Electrolytes Research Articles

Selenium-Doped Sulfurized Polyacrylonitrile Hybrid Cathodes with Ultrahigh Sulfur Content for High-Performance Solid-State Lithium Sulfur Batteries.

The solid-state lithium sulfur battery (SSLSB) is an attractive next-generation energy storage system by reason of its remarkably high energy density and safety. However, the SSLSB still faces critical challenges, such as sluggish reaction kinetics, mismatched interface, and undesirable reversible capacity. Herein, a high-performance SSLSB is reported using sulfurized polyacrylonitrile with rich selenium-doped sulfur (Se/S-S@pPAN) as a cathode and poly(ethylene oxide)/Li7La3Zr1.4Ta0.6O12 (PEO-LLZTO) as an electrolyte. The sulfur content of the cathode up to 60.9 wt % can be achieved by dispersing selenium sulfide (SeSx) species in the sulfurized polyacrylonitrile (S@pPAN) skeleton at a molecular level. Selenium as a eutectic accelerator can be uniformly distributed in the composite through the Se-S bond and can accelerate the reaction kinetics. The PEO-LLZTO hybrid solid-state electrolyte (SSE) displays an attractive electrochemical performance and provides an intimate contact with electrodes. At 60 °C, Se/S-S@pPAN delivers an impressive discharge capacity of 1042 mAh g-1 at 0.1C and 445 mAh g-1 at 1C. Additionally, the LiFePO4 cathodes combined with PEO-LLZTO deliver a high reversible capacity (158.9 mAh g-1, 1C) and an ultralong lifespan (a capacity retention of 80%, 1000 cycles) at 1C. The synergetic design of the high-performance sulfur cathode and the organic/inorganic hybrid electrolyte is crucial for enabling the high-performance SSLSB.

Multilayer hybrid solid-state electrolyte membrane for the high rate and long-life cycle performance of lithium-metal batteries

Hybrid solid-state electrolytes (HSEs) can be used to increase the electrochemical performance of lithium-metal batteries (LMBs), while also suppressing dendrite formation and preventing flammable behavior and electrolyte leakage, which are frequently present in conventional organic-liquid electrolytes. Notably, multilayer HSE membranes have received increasing emphasis since they can significantly ameliorate the interface contact toward electrodes and the mechanical strength. In this current work, we fabricated multilayer HSE membranes via a solution-casting technique that incorporated poly(vinylidene fluoride–co–hexafluoropropylene) (PVDF-HFP), polydopamine-modified Li6.28La3Zr2Al0.24O12 (PDA@LLZAO) filler, succinonitrile (SN) and lithium bis(trifluoromethane sulfonyl)imide (LiTFSI). The resulting HSE membrane exhibited a high ionic conductivity (2.49 ×10−4 S cm−1 at 30 ℃), transference number of 0.65, and excellent electrochemical window (4.80 V). The symmetrical cell featuring Li/HSE/Li was stable and cycled without short circuiting for 1000 h during the Li plating/stripping cycles. Furthermore, the coin-type cell assembled with LiFePO4/HSE/Li showed an initial discharge capacity of 134.7 mAh g1 and exhibited superior retained capacity and average coulombic efficiency of 93.45% and 99.39%, respectively, after 687 cycles at 2 C and 30 ℃. Therefore, the as-prepared multilayer HSE is a promising SSE for next-generation LMBs.

Self-assembled hydrated copper coordination compounds as ionic conductors for room temperature solid-state batteries

As the core component of solid-state batteries, neither current inorganic solid-state electrolytes nor solid polymer electrolytes can simultaneously possess satisfactory ionic conductivity, electrode compatibility and processability. By incorporating efficient Li+ diffusion channels found in inorganic solid-state electrolytes and polar functional groups present in solid polymer electrolytes, it is conceivable to design inorganic-organic hybrid solid-state electrolytes to achieve true fusion and synergy in performance. Herein, we demonstrate that traditional metal coordination compounds can serve as exceptional Li+ ion conductors at room temperature through rational structural design. Specifically, we synthesize copper maleate hydrate nanoflakes via bottom-up self-assembly featuring highly-ordered 1D channels that are interconnected by Cu2+/Cu+ nodes and maleic acid ligands, alongside rich COO− groups and structural water within the channels. Benefiting from the combination of ion-hopping and coupling-dissociation mechanisms, Li+ ions can preferably transport through these channels rapidly. Thus, the Li+-implanted copper maleate hydrate solid-state electrolytes shows remarkable ionic conductivity (1.17 × 10−4 S cm−1 at room temperature), high Li+ transference number (0.77), and a 4.7 V-wide operating window. More impressively, Li+-implanted copper maleate hydrate solid-state electrolytes are demonstrated to have exceptional compatibility with both cathode and Li anode, enabling long-term stability of more than 800 cycles. This work brings new insight on exploring superior room-temperature ionic conductors based on metal coordination compounds.

Preparation and characterization of hybrid solid-state electrolytes for high performance lithium-ion batteries

Hybrid solid-state electrolytes are emerging as a promising solution to achieve high ionic conductivity, excellent mechanical properties and good safety for developing high-performance rechargeable batteries. In this work, a polymer (PAN)-based hybrid solid-state electrolyte is designed and synthesized. The composite membrane (PLL) is composed of polyacrylonitrile (PAN) matrix, bistrifluoromethanesulfonimide lithium salt (LiTFSI) and Li1.3Al0.3Ti1.7(PO4)3 (LATP) particles. The solid-state lithium battery including the as-synthesized composite membrane, Li metal and LiNi0.8Co0.1Mn0.1O2 exhibits an initial discharge capacity of 197 mAh g−1 at a charge/discharge current density of 0.5 C at room temperature. The battery using the PLL-20 electrolyte exhibits the highest stable cycling performance and highest reversible capability than those of the batteries with PLL-10, PLL-30 membrane electrolytes and commercial PE separator, respectively.

Polymeric Backbone Eutectogel Electrolytes for High-Energy Lithium-Ion Batteries.

This work introduces a polymeric backbone eutectogel (P-ETG) hybrid solid-state electrolyte with an N-isopropylacrylamide (NIPAM) backbone for high-energy lithium-ion batteries (LIBs). The NIPAM-based P-ETG is (electro)chemically compatible with commercially relevant positive electrode materials such as the nickel-rich layered oxide LiNi0.6Mn0.2Co0.2O2 (NMC622). The chemical compatibility was demonstrated through (physico)chemical characterization methods. The nonexistence (within detection limits) of interfacial reactions between the electrolyte and the positive electrode, the unchanged bulk crystallographic composition, and the absence of transition metal ions leaching from the positive electrode in contact with the electrolyte were demonstrated by Fourier transform infrared spectroscopy, powder X-ray diffraction, and elemental analysis, respectively. Moreover, the NIPAM-based P-ETG demonstrates a wide electrochemical stability window (1.5-5.0 V vs Li+/Li) and a reasonably high ionic conductivity at room temperature (0.82 mS cm-1). The electrochemical compatibility of a high-potential NMC622-containing positive electrode and the P-ETG is further demonstrated in Li|P-ETG|NMC622 cells, which deliver a discharge capacity of 134, 110, and 97 mAh g-1 at C/5, C/2, and 1C, respectively, after 90 cycles. The Coulombic efficiency is >95% at C/5, C/2, and 1C. Hence, gaining scientific insights into the compatibility of the electrolytes with positive electrode materials that are relevant to the commercial market, like NMC622, is important because this requires going beyond the electrolyte design itself, which is essential to their practical applications.

Lithium Self-Diffusion in a Polymer Electrolyte for Solid-State Batteries: ToF-SIMS/ssNMR Correlative Characterization and Modeling Based on Lithium Isotopic Labeling.

Manufacturers aim to commercialize efficient and safe batteries by finding new strategies. Solid-state electrolytes can be seen as an opportunity to develop batteries with a high energy density. They allow the use of lithium foil as the anode, increasing the energy density. Also, they are composed of nonflammable materials making them safer than liquid electrolytes. However, to enhance the electrochemical performances of forthcoming solid-state lithium metal batteries, phenomena governing ionic conductivity have yet to be mastered in such devices. Lithium isotopic tracing was successfully used in previous works to further understand lithium ion transport mechanisms in batteries. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and 6/7Li high-resolution solid-state nuclear magnetic resonance (ssNMR) spectroscopy are two complementary techniques probing local and global scale, respectively. Both techniques can distinguish lithium isotopes. Here, four polymer membranes were elaborated with the same lithium concentration, but with various isotopic enrichments from 7.6 to 95.4% of 6Li. The selected material was a poly(ethylene oxide) (PEO) membrane containing lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) as lithium salt. They are widely studied in the lithium battery field. First, reliable ToF-SIMS and ssNMR methodologies were validated in light of the converging results. They led to accurate determination of lithium isotopic abundance of polymer membranes with a 1 or a 2% uncertainty, respectively. Then, the developed methodologies were applied to characterize lithium self-diffusion in a polymer membrane. Furthermore, numerical simulations based on a two-dimensional diffusion model compared with ToF-SIMS analyses allowed us to extract a lithium self-diffusion coefficient of 1.6 × 10-12 m2·s-1 at 60 °C, which complements other published values. The robust methodologies described in this work can be extended to various applications and materials. They stand as powerful strategies to better understand lithium ionic transport, especially in multiphase materials, for example, in hybrid solid-state electrolytes.

Enhanced Capacity Retention of Li3V2(PO4)3-Cathode-Based Lithium Metal Battery Using SiO2-Scaffold-Confined Ionic Liquid as Hybrid Solid-State Electrolyte.

Li3V2(PO4)3 (LVP) is one of the candidates for high-energy-density cathode materials matching lithium metal batteries due to its high operating voltage and theoretical capacity. However, the inevitable side reactions of LVP with a traditional liquid-state electrolyte under high voltage, as well as the uncontrollable growth of lithium dendrites, worsen the cycling performance. Herein, a hybrid solid-state electrolyte is prepared by the confinement of a lithium-containing ionic liquid with a mesoporous SiO2 scaffold, and used for a LVP-cathode-based lithium metal battery. The solid-state electrolyte not only exhibits a high ionic conductivity of 3.14 × 10-4 S cm-1 at 30 °C and a wide electrochemical window of about 5 V, but also has good compatibility with the LVP cathode material. Moreover, the cell paired with a solid-state electrolyte exhibits good reversibility and can realize a stable operation at a voltage of up to 4.8 V, and the discharge capacity is well-maintained after 100 cycles, which demonstrates excellent capacity retention. As a contrast, the cell paired with a conventional liquid-state electrolyte shows only an 87.6% discharge capacity retention after 100 cycles. In addition, the effectiveness of a hybrid solid-state electrolyte in suppressing dendritic lithium is demonstrated. The work presents a possible choice for the use of a hybrid solid-state electrolyte compatible with high-performance cathode materials in lithium metal batteries.

Hybrid Dynamic Covalent Network as a Protective Layer and Solid-State Electrolyte for Stable Lithium-Metal Batteries.

Lithium (Li) metal is a highly promising anode material for next-generation high-energy-density batteries, while Li dendrite growth and the unstable solid electrolyte interphase layer inhibit its commercialization. Herein, a chemically grafted hybrid dynamic network (CHDN) is rationally designed and synthesized by the 4,4'-thiobisbenzenamine cross-linked poly(poly(ethylene glycol) methyl ether methacrylate-r-glycidyl methacrylate) and (3-glycidyloxypropyl) trimethoxysilane-functionalized SiO2 nanoparticles, which is utilized as a protective layer and hybrid solid-state electrolyte (HSE) for stable Li-metal batteries. The presence of a dynamic exchangeable disulfide affords self-heability and recyclability, and the chemical attachment between SiO2 nanoparticles and the polymer matrix enables the homogeneous distribution of inorganic fillers and mechanical robustness. With integrated flexibility, fast segmental dynamics, and autonomous adaptability, the as-prepared CHDN-based protective layer enables superior electrochemical performance in half cells and full cells (capacity retention of 83.7% over 400 cycles for the CHDN@Li/LiFePO4 cell at 1 C). Furthermore, benefiting from intimate electrode/electrolyte interfacial contact, CHDN-based solid-state cells deliver excellent electrochemical performance (capacity retention of 89.5% over 500 cycles for the Li/HSE/LiFePO4 cell at 0.5 C). In addition, the Li/HSE/LiFePO4 pouch cell exhibits superior safety, even exposing various physical damage conditions. This work thereby provides a fresh insight into a rational design principle for dynamic network-based protective layers and solid-state electrolytes for battery applications.

Understanding Lithium-Ion Dynamics in Single-Ion and Salt-in-Polymer Perfluoropolyethers and Polyethyleneglycol Electrolytes Using Solid-State NMR

Lithium metal batteries with high energy densities can enable a revolution in energy storage and accelerate shifts in electric transportation and electricity generation. However, several morphological and electro-chemo-mechanical challenges impede their development. Solid-state electrolytes such as those based on polymers show great promise in replacing liquid electrolytes in lithium metal batteries. Polyether-based polymer electrolytes are the most investigated but are plagued by low room-temperature ionic conductivity and poor oxidative stability. Hence, there is great need for the development and understanding of ion transport in new classes of polymer electrolytes. Perfluoropolyether (PFPE)-based electrolytes have shown improved oxidative stability, but little is understood about their lithium solvation and transport mechanism. In this work, we use multinuclear solid-state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy to investigate the lithium cation environment and mobility in crosslinked single-ion and salt-in-polymer PFPE electrolytes and compare it directly to that of well-known polyethylene glycol (PEG) electrolytes. We show that the interaction of the lithium cation with the polymer backbone is weaker in PFPE systems compared to PEG, likely resulting in stronger ion pairing in the PFPE systems. Line shape analyses show lower lithium mobility in PFPE electrolytes despite lower activation energies being derived from spin-lattice relaxation (T1) measurements as compared to those for the PEG systems. The rapid relaxation is instead ascribed to the local fluctuations caused by polymer backbone mobility. By studying different modes of ion binding (single-ion vs salt-in-polymer), we show that differences across polymer backbones (PFPE vs PEG) have a greater effect on mobility than differences in ion binding modes within each polymer class (especially when single-ion conducting site density is not high). Our ability to use MAS NMR to study polymer electrolytes in their native state opens new opportunities to develop and understand novel polymer or hybrid solid-state electrolytes for next-generation lithium metal batteries.

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.

A review of polymers in sulfide-based hybrid solid-state electrolytes for all-solid-state lithium batteries

The practical application of hybrid solid-state electrolytes involves the incorporation of polymers. This review focuses on the fabrication process of sheet-type solid-state electrolytes utilizing appropriate polymer binders.

A hybrid solid-state electrolyte endows a Li metal battery with excellent cycling life at 120 °C

A hybrid solid-state electrolyte designed based on an activated Al-based metal–organic framework features high lithium-ion conductivity and excellent stability, which provides a practical method for the application of high-temperature batteries.

Hybrid solid state electrolytes blending NASICON-type Li1+xAlxTi2–x(PO4)3 with poly(vinylidene fluoride-co-hexafluoropropene) for lithium metal batteries

Lithium-ion batteries (LIBs) with Li metal as the anode electrode are very promising energy storage systems for high energy/power density applications. However, Li dendrite formation and growth on the Li anode due to non-uniform Li metal deposition is one of the major issues yet to be addressed. In this work, novel hybrid solid state electrolytes (SSEs) were developed through blending poly(vinylidene fluoride-hexafluoro propylene) (PVDF-HFP), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt, and sodium superionic conductor (NASICON)-type Li1+xAlxTi2‒x(PO4)3 (LATP) powders. The LATP powders were synthesized by the sol-gel technique followed by calcination at 850 °C. The as-prepared LATP particles formed a well-defined crystalline structure with a rhombohedral lattice. The LATP content within the hybrid SSEs plays a crucial role in improving the mechanical durability, ionic conductivity, rate capability, discharge capacity, and cyclic stability. Analyzing various SSE configurations, an optimal ratio of LATP was determined (i.e., 10–15 wt.%) enabling an ultra-high ionic conductivity of ∼1.11 × 10–4 S cm–1. Employing the LATP-based SSE developed in this work, the dissolution of iron from the LiFePO4 cathode was mitigated and a stable solid electrolyte interphase layer was formed resulting in uniform Li metal deposition along with exceptional cyclic durability during long-duration charge/discharge cycling.

Efficient and Stable Fiber Dye-Sensitized Solar Cells Based on Solid-State Li-TFSI Electrolytes with 4-Oxo-TEMPO Derivatives.

Fiber-shaped dye-sensitized solar cells (FDSSCs) with flexibility, weavablity, and wearability have attracted intense scientific interest and development in recent years due to their low cost, simple fabrication, and environmentally friendly operation. Since the Grätzel group used the organic radical 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) as the redox system in dye-sensitized solar cells (DSSCs) in 2008, TEMPO has been utilized as an electrolyte to further improve power conversion efficiency (PCE) of solar cells. Hence, the TEMPO with high catalyst oxidant characteristics was developed as a hybrid solid-state electrolyte having high conductivity and stability structure by being integrated with a lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) film for FDSSCs. The optimized 4-Oxo TEMPO (OX) based solid-state FDSSC (SS-FDSSC) showed the PCE of up to 6%, which was improved by 34.2% compared to that of the reference device with 4.47%. The OX-enhanced SS-FDSSCs reduced a series resistance (Rs) resulting in effective electron extraction with improved short-circuit current density (JSC), while increasing a shunt resistance (Rsh) to prevent the recombination of photo-excited electrons. The result is an improvement in a fill factor (FF) and consequently a higher value for the PCE.

High-throughput development of Na2ZnSiO4-based hybrid electrolytes for sodium-ion batteries

All-solid sodium-ion batteries are a very attractive technology for large scale applications such as grid storage. Herein, a hybrid solid-state electrolyte (HybSSE) made of halloysite clay-derived Na2ZnSiO4 ceramic and ionic liquid is developed by way of high-throughput methods. This involved making over 700 ceramics in order to both optimize the synthesis and screen 22 different substituents at 8 different substitution levels. This work yielded HybSSE with ionic conductivities as high as 0.453 mS cm−1 at room temperature and 2.27 mS cm−1 at 48 °C. This is an important improvement by a factor of nearly 20 over those reported previously. The improved ionic conductivities now make this HybSSE a viable candidate for quasi-solid Na-ion batteries. Further screening of electronic conductivity shows that dendrite growth within all tested HybSSEs is not expected to be a concern, nor is electrochemical instability on the cathode side. By contrast, all HybSSEs are found to be unstable against sodium metal, with the lowest decomposition potential being 0.8 V vs. Na. Thus, sodium metal anodes are not feasible here without the use of a buffering layer. The results therefore represent important improvements in this class of electrolytes and also guide future research and development.

A Direct View on Li-Ion Transport and Li-Metal Plating in Inorganic and Hybrid Solid-State Electrolytes.

ConspectusDriven by the intrinsic safety and potential to achieve higher energy densities, solid-state Li-metal batteries are intensively researched. The ideal solid electrolyte should possess a high conductivity, should have electrochemical stability both toward the Li-metal anode and to high voltage cathodes, should suppress dendrites, should provide flexibility to deal with the volumetric changes of the electrodes, and should be easy to process. This challenging combination is to date not fulfilled by any solid electrolyte, be it organic, inorganic, or even a hybrid of the two. Pushing the development of solid electrolytes toward reversible room temperature operation when used in tandem with Li-metal anodes demands an understanding of critical processes that determine the properties of the solid electrolyte. These include the complex Li-ion transport as well as the Li-metal plating processes. This already presents the first experimental hurdle as the ability to directly and noninvasively monitor the Li-ion kinetics, Li densities, and Li chemistries, under in/situ or operando, is not trivial.The scope of this Account is the investigation and improvement of solid electrolytes, with the emphasis on the possibilities offered by solid-state NMR and neutron depth profiling as direct probes for the study of critical processes that involve Li ions and Li metal. Solid-state NMR allows us to unravel the complex interface chemical environment and the diffusion processes both in the bulk solid electrolyte and in the interface environment. These studies shed light on the role of interface composition, wetting and space-charge layers, on the macroscopic battery performance. Another technique that enables probing Li directly is operando neutron depth profiling, which allows us to determine the Li density as a function of depth. It provides a noninvasive and effectively nondestructive tool to examine delamination, irreversible reactions and dendrite formation during plating/stripping. Results demonstrate that it is very challenging to maintain the contact between Li metal and the SE during cycling, especially for the “anode-less” or “anode-free” configuration under low-pressure conditions. A perspective is provided on the potential improvement of the Li-ion transport, dendrite suppression, and preventing Li-metal-solid-electrolyte delamination as well as on the potential role of solid-state NMR and NDP techniques to guide these developments.

In Situ Synthesis of a Li6.4La3Zr1.4Ta0.6O12/Poly(vinylene carbonate) Hybrid Solid-State Electrolyte with Enhanced Ionic Conductivity and Stability

<i>In Situ</i> Synthesis of a Li_6.4La₃Zr_1.4Ta_0.6O₁₂/Poly(vinylene carbonate) Hybrid Solid-State Electrolyte with Enhanced Ionic Conductivity and Stability

Shape-Controlled TiO2 Nanomaterials-Based Hybrid Solid-State Electrolytes for Solar Energy Conversion with a Mesoporous Carbon Electrocatalyst.

One-dimensional (1D) titanium dioxide (TiO2) is prepared by hydrothermal method and incorporated as nanofiller into a hybrid polymer matrix of polyethylene glycol (PEG) and employed as a solid-electrolyte in dye-sensitized solar cells (DSSCs). Mesoporous carbon electrocatalyst with a high surface area is obtained by the carbonization of the PVDC-g-POEM double comb copolymer. The 1D TiO2 nanofiller is found to increase the photoelectrochemical performance. As a result, for the mesoporous carbon-based DSSCs, 1D TiO2 hybrid solid-state electrolyte yielded the highest efficiencies, with 6.1% under 1 sun illumination, in comparison with the efficiencies of 3.9% for quasi solid-state electrolyte and 4.8% for commercial TiO2 hybrid solid-state electrolyte, respectively. The excellent photovoltaic performance is attributed to the improved ion diffusion, scattering effect, effective path for redox couple transfer, and sufficient penetration of 1D TiO2 hybrid solid-state electrolyte into the electrode, which results in improved light-harvesting, enhanced electron transport, decreased charge recombination, and decreased resistance at the electrode/electrolyte interface.

Direct Ink Writing of Li1.3 Al0.3 Ti1.7 (PO4 )3 -Based Solid-State Electrolytes with Customized Shapes and Remarkable Electrochemical Behaviors.

All-solid-state lithium batteries have received extensive attention due to their high safety and promising energy density and are considered as the next-generation electrochemical energy storage system. However, exploring solid-state electrolytes in customized geometries without sacrificing the ionic transport is significant yet challenging. Herein, various 3D printable Li1.3 Al0.3 Ti1.7 (PO4 )3 (LATP)-based inks are developed to construct ceramic and hybrid solid-state electrolytes with arbitrary shapes as well as high conductivities. The obtained inks show suitable rheological behaviors and can be successfully extruded into solid-state electrolytes using the direct ink writing (DIW) method. As-printed free-standing LATP ceramic solid-state electrolytes deliver high ionic conductivity up to 4.24×10-4 Scm-1 and different shapes such as "L", "T," and "+" can be easily realized without sacrificing high ionic transport properties. Moreover, using this printing method, LATP-based hybrid solid-state electrolytes can be directly printed on LiFePO4 cathodes for solid-state lithium batteries, where a high discharge capacity of 150mAhg-1 at 0.5C is obtained. The DIW strategy for solid-state electrolytes demonstrates a new way toward advanced solid-state energy storage with the high ionic transport and customized manufacturing ability.

Self-adaptive multiblock-copolymer-based hybrid solid-state electrolyte for safe and stable lithium-metal battery

The dramatic volume change during the Li plating/stripping process has aroused brittle solid electrolyte interphase as well as weak interfacial compatibility between electrolyte and electrode, which results in capacity fading and safety hazards. We design elastic multiblock copolymers (mBCPs) with excellent extensibility up to 600% to address this problem. The best recovery rate of mBCP is 82% after 100 times of cyclic tensile tests. The mBCPs are regarded as elastomers that enable close contact with electrode surface during cycling. The elastic mBCPs are then mixed with lithium salt and high ionic conductivity inorganic ceramics to prepare hybrid solid-state electrolytes (HSSEs). The HSSEs are expected to possess self-adaptive property making good interfacial connection due to the mBCPs. The best HSSEs demonstrate high ionic conductivity of 0.14 mS cm−1 with a Li ion transference number of 0.55 and wide electrochemical window of 5.2 V at 25°C. Excellent cycling performance with long battery life is achieved by utilizing the self-adaptive HSSE: the Li metal electrode cycled for 150 times retains 96% coulombic efficiency in Li/HSSE/LiFePO4 cells, and stable cycling of 500 h is achieved in the symmetric cells.