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Electrochemical-mechanical coupling poses enormous challenges to the interfacial and structural stability but create new opportunities to design innovative all-solid-state batteries from scratch. Relying on the solid-solid constraint in the space-limited domain structure, we propose to exploit the lithiation-induced stress to drive the active materials creep, thereby improving the structural integrity. For demonstration, we fabricate the creep-type all-solid-state cathode using creepable Se material and an all-in-one rigid ionic/electronic conducting Mo6Se8 framework. As indicated by the in-situ experiment and numerical simulation, this cathode presents unique capabilities in improving interparticle contact and avoiding particle fracture, leading to its superior electrochemical performance, including a superior long-cycle life of more than 3000 cycles at 0.5 C and a high volumetric energy density of 2460 Wh/L at the cathode level. We believe this innovative strategy to utilize mechanics to boost the electrochemical performance could shed light on the future design of all-solid-state batteries for practical applications. Electrochemical-mechanical issues bring challenges but create new opportunities to design innovative all-solid-state batteries. Here, the authors propose to use the (de)lithiation-stress-creep synergistic time-dependent evolution to boost the electrochemical performance of all-solid-state batteries. [ABSTRACT FROM AUTHOR]

The electrochemical stability and contact reliability of heterointerfaces between the solid electrolyte (SE) and electrode are critical for all-solid-state batteries (ASSBs), particularly much more challenging for high-voltage ASSBs, owing to the limited thermodynamically electrochemical window and mechanical inflexibility of SE, aggravating interfacial side reactions and contact failure. Considering all those issues originating from intrinsic heterogeneity in physicochemical features between the cathode material and SE, we are thinking about simplifying the heterointerfaces into a homointerface as a permanent cure to solve all electrochemical-mechanical interfacial failure. Herein, we propose monophase cathodes to construct thermo-dynamically stable all-in-one homointerfaces in ASS electrodes, removing unstable heterointerfaces by excluding SEs and intrinsically eliminating the Li chemical potential gap to avoid the formation of lithium-depleted space-charge layer and highly resistive mixed ion–electron conductor interphase. Our conception is successfully validated in the layered transition-metal oxide cathodes, which display outstanding stability no matter the MH-LiCoO2 cathode charging to 4.7 V or MH-Li1.2Mn0.54Ni0.13-Co0.13O2 cathode charging to 5.3 V. It is undeniable that our current version of above-illustrated MH-cathodes would bring out some new challenges for the practical application due to abandoning the SE. However, we believe our work also offers a brand-new direction to ultimately address the electrochemical–mechanical interfacial issues that would be promising for high-energy ASSBs with more discoveries of advanced monophase cathodes in the future. [ABSTRACT FROM AUTHOR]

Aluminum current collectors are widely used in nonaqueous batteries owing to their cost-effectiveness, lightweightness, and ease of fabrication. However, they are excluded from aqueous batteries due to their severe corrosion in aqueous solutions. Here, we propose hydrolyzation-type anodic additives to form a robust passivation layer to suppress corrosion. These additives dramatically lower the corrosion current density of aluminum by nearly three orders of magnitude to ~10−6 A cm−2. In addition, realizing that electrochemical corrosion accompanies anode prelithiation, we propose a prototype of self-prolonging aqueous Li-ion batteries (Al ||LiMn2O4 ||TiO2), whose capacity retention rises from 49.5% to 70.1% after 200 cycles. A sacrificial aluminum electrode where electrochemical corrosion is utilized is introduced as an electron supplement to prolong the cycling life of aqueous batteries. Our work addresses the short-life issue of aqueous batteries resulting from the corrosion of the current collector and lithium loss from side reactions. Aqueous batteries have a short lifespan due to Al current collector corrosion and Li loss from side reactions on the anode. Here, the authors propose a prototype of self-prolonging aqueous Li-ion batteries by introducing hydrolyzation-type anodic additives to regulate Al corrosion-passivation. [ABSTRACT FROM AUTHOR]

The reversibility of lithium (Li) metal anodes is highly susceptible to temperature, owing to the aggravated side reactions at high temperatures and serious Li dendrite growth at low temperatures. Thus it is extremely challenging to simultaneously realize the high Li reversibility in both low and high temperature scenarios. Herein, an oxygen-free solvent (n-hexane, HEX) assisted with the hexyl methyl ether and 1 mol L−1 lithium bis(fluorosulfonyl)imide is proposed to constitute an electrolyte for temperature-immune lithium metal batteries. It demonstrates that the HEX not only greatly suppresses the solvent reduction even at high temperatures but also weaken the Li+–solvent interaction for the facile Li-ion desolvation, leading to high Li Coulombic efficiencies (99.59% at 25 °C, 99.30% at 60 °C and 98.75% at −30 °C) and the dendrite-free Li plating from −30 °C to 60 °C. Benefitting from the low density and temperature-immune properties of our electrolyte, the sulfurized polyacrylonitrile (3.8 mAh cm−2)∥Li (60 µm) pouch-cells deliver 278 Wh kg−1 energy density and maintain the stable performance over 50 cycles, and retain 248 and 320 Wh kg−1 energy density at −30 °C and 60 °C, respectively. This work provides a new perspective on the electrolyte design for wide-temperature Li metal batteries. [ABSTRACT FROM AUTHOR]

Aggressive chemistry involving Li metal anode (LMA) and high-voltage LiNi0.8Mn0.1Co0.1O2 (NCM811) cathode is deemed as a pragmatic approach to pursue the desperate 400 Wh kg−1. Yet, their implementation is plagued by low Coulombic efficiency and inferior cycling stability. Herein, we propose an optimally fluorinated linear carboxylic ester (ethyl 3,3,3-trifluoropropanoate, FEP) paired with weakly solvating fluoroethylene carbonate and dissociated lithium salts (LiBF4 and LiDFOB) to prepare a weakly solvating and dissociated electrolyte. An anion-enrichment interface prompts more anions' decomposition in the inner Helmholtz plane and higher reduction potential of anions. Consequently, the anion-derived interface chemistry contributes to the compact and columnar-structure Li deposits with a high CE of 98.7% and stable cycling of 4.6 V NCM811 and LiCoO2 cathode. Accordingly, industrial anode-free pouch cells under harsh testing conditions deliver a high energy of 442.5 Wh kg−1 with 80% capacity retention after 100 cycles. The implementation of Li metal anode with high-voltage Ni/Co rich cathode is plagued by low coulombic efficiency and inferior cycling stability. Here authors propose an anion-enriched interface to facilitate the columnar-structure of Li deposits to solve this issue. [ABSTRACT FROM AUTHOR]

Poly(ethylene oxide)-based solid-state electrolytes are widely considered promising candidates for the next generation of lithium and sodium metal batteries. However, several challenges, including low oxidation resistance and low cation transference number, hinder poly(ethylene oxide)-based electrolytes for broad applications. To circumvent these issues, here, we propose the design, synthesis and application of a fluoropolymer, i.e., poly(2,2,2-trifluoroethyl methacrylate). This polymer, when introduced into a poly(ethylene oxide)-based solid electrolyte, improves the electrochemical window stability and transference number. Via multiple physicochemical and theoretical characterizations, we identify the presence of tailored supramolecular bonds and peculiar morphological structures as the main factors responsible for the improved electrochemical performances. The polymeric solid electrolyte is also investigated in full lithium and sodium metal lab-scale cells. Interestingly, when tested in a single-layer pouch cell configuration in combination with a Li metal negative electrode and a LiMn0.6Fe0.4PO4-based positive electrode, the polymeric solid-state electrolyte enables 200 cycles at 42 mA·g−1 and 70 °C with a stable discharge capacity of approximately 2.5 mAh when an external pressure of 0.28 MPa is applied. Solid-state polymer electrolytes are crucial for developing future rechargeable batteries, but they are still limited in performance. Here, the authors designed a topological polymeric solid electrolyte, enabling an all-solid-state high-voltage lithium metal pouch cell to cycle 200 times efficiently. [ABSTRACT FROM AUTHOR]

Liquid electrolyte plays a key role in commercial lithium-ion batteries to allow conduction of lithium-ion between cathode and anode. Traditionally, taking into account the ionic conductivity, viscosity and dissolubility of lithium salt, the salt concentration in liquid electrolytes is typically less than 1.2?mol?l?1. Here we show a new class of 'Solvent-in-Salt' electrolyte with ultrahigh salt concentration and high lithium-ion transference number (0.73), in which salt holds a dominant position in the lithium-ion transport system. It remarkably enhances cyclic and safety performance of next-generation high-energy rechargeable lithium batteries via an effective suppression of lithium dendrite growth and shape change in the metallic lithium anode. Moreover, when used in lithium-sulphur battery, the advantage of this electrolyte is further demonstrated that lithium polysulphide dissolution is inhibited, thus overcoming one of today's most challenging technological hurdles, the 'polysulphide shuttle phenomenon'. Consequently, a coulombic efficiency nearing 100% and long cycling stability are achieved. [ABSTRACT FROM AUTHOR]