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[Display omitted] • PTFE-based dry-processed technology is used to prepare flexible Li 6 PS 5 Cl membrane and FeS 2 composite cathode membrane. • Due to the robust adhesion of PTFE, intimate contact is obtained at 100 MPa which is one-fifth of conventional pressure. • PTFE attaches the electrochemical sluggish products to an ion–electron conductive network to improve cyclic stability. • The flexible FeS 2 -ASSLBs exhibit excellent cyclic stability under the stack pressure of 100 MPa. All-solid-state lithium batteries (ASSLBs) are considered promising energy storage systems due to their high energy density and inherent safety. However, scalable fabrication of ASSLBs based on transition metal sulfide cathodes through the conventional powder cold-pressing method with ultrahigh stacking pressure remains challenging. This article elucidates a dry process methodology for preparing flexible and high-performance FeS 2 -based ASSLBs under low stack pressure by utilizing polytetrafluoroethylene (PTFE) binder. In this design, fibrous PTFE interweaves Li 6 PS 5 Cl particles and FeS 2 cathode components, forming flexible electrolyte and composite cathode membranes. Beneficial to the robust adhesion, the composite cathode and Li 6 PS 5 Cl membranes are tightly compacted under a low stacking pressure of 100 MPa which is a fifth of the conventional pressure. Moreover, the electrode/electrolyte interface can sustain adequate contact throughout electrochemical cycling. As expected, the FeS 2 -based ASSLBs exhibit outstanding rate performance and cyclic stability, contributing a reversible discharged capacity of 370.7 mAh g−1 at 0.3C after 200 cycles. More importantly, the meticulous dQ/dV analysis reveals that the three-dimensional PTFE binder effectively binds the discharge products with sluggish kinetics (Li 2 S and Fe) to the ion–electron conductive network in the composite cathode, thereby preventing the electrochemical inactivation of products and enhancing electrochemical performance. Furthermore, FeS 2 -based pouch-type cells are fabricated, demonstrating the potential of PTFE-based dry-process technology to scale up ASSLBs from laboratory-scale mold cells to factory-scale pouch cells. This feasible dry-processed technology provides valuable insights to advance the practical applications of ASSLBs. [ABSTRACT FROM AUTHOR]

[Display omitted] High-energy–density lithium-rich Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 is regarded as one of the most promising cathode materials for lithium-ion batteries. However, its practical application is restricted by critical kinetics drawbacks and poor low-temperature electrochemical performances. In this research, Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 submicron particles coated by a Li 7 La 3 Zr 2 O 12 (LLZO) layer and co-doped by La/Zr cations has been fabricated via a facile one-pot sol–gel technique and subsequent heat treatment. The coating LLZO layer with a few nanometers is able to build a rapid lithium-ion transport channel for adjacent particles and suppress severe side reactions between active material and the electrolyte. Moreover, large-radius La/Zr cations co-doping can broaden the diffusion paths of lithium ions, hinder the detrimental structural transformation, and improve the electrochemical structure stability of the cathode during repeated cycles. Owing to numerous merits from this multifunctional surface modification strategy, the modified Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 composite exhibits the significantly decreased interface impedance, enhanced Li+ diffusion kinetics and mitigated phase transformation, as well as excellent low-temperature electrochemical performance. It can contribute ultrahigh capacities of 173.8 mAh g−1 at −10 ℃ and 134.1 mAh g−1 at −20 ℃, respectively, displaying great application prospects of Li-rich cathode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • An electronic-ionic bi-functional conduction β-LPS/SG/Li 4.4 Sn was prepared for lithium anode skeleton. • Internally loaded Li 4.4 Sn has high Li binding energy and low nucleation overpotential. • Externally coated β-L 3 PS 4 has high ion conductivity and low Li+ activation energy. • The bi-functional framework guides Li deposition in the hollow SG, inhibits the dendrite growth and side reactions. • The anode has a long life of up to 2800 h, low overpotential (∼13 mV) and high coulomb efficiency of 99.8 % after 470 cycles. Although Li metal is considered the most potential anode for Li based batteries, the repeatedly large volume variation and low Coulombic efficiency (CE) are still serious challenges for commercial application. Herein, the interconnect closed hollow graphene spheres with electronic-ionic bi-functional conduction network containing Li 4.4 Sn nanoparticles loaded internally and β-Li 3 PS 4 solid electrolyte layer coated externally (β-LPS/SG/Li 4.4 Sn) is proposed to achieve uniform and dense Li deposition. Density functional theory (DFT) calculation and experimental results show that Li 4.4 Sn owns larger Li binding energy and lower nucleation overpotential than spherical graphene (SG), thus being able to guide Li traversing and depositing inside the hollow spheres. The Tafel curves, Li+ diffusion activation energy and experimental results reveal that the β-Li 3 PS 4 coating layer significantly improves the ionic conductivity of the negative skeleton, covers the defect sites on the SG surface, provides continuous ion transmission channels and accelerates Li+ migration rate. The synergy of both can inhibit the formation of dendritic Li and reduce side reaction between freshly deposited lithium and the organic electrolyte. It's found that Li is preferentially deposited within the SG, evenly deposited on the spherical shell surface until it's completely filled to obtain a dense lithium layer without tip effect. As a result, the β-LPS/SG/Li 4.4 Sn anode exhibits a long life of up to 2800 h, an extremely low overpotential (∼13 mV) and a high CE of 99.8 % after 470 cycles. The LiFePO 4 -based full cell runs stably with a high capacity retention of 86.93 % after 800 cycles at 1C. It is considered that the novel structure design of Li anode skeleton with electron-ionic bi-functional conduction is a promising direction to construct long-term stable lithium metal anodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • I-CNT with enhanced electronic conductivity is reported as a multifunctional sulfur skeleton material. • I-CNT skeleton boosts adsorption effect and conversion reaction kinetics of LiPSs. • DFT calculation, quasi in-situ EIS and in-situ Raman spectroscopy reveal the polysulfides conversion mechanism. • The Li 2 S potentiostatic deposition i - t curves also confirm the improved liquid–solid reaction kinetics. • I-CNT@S exhibits satisfactory cycle stability of 528.9 mAh g−1 at 2C after 700 cycles. Compared with lithium-ion batteries (LIBs), lithium-sulfur batteries (LSBs), based on electrochemical reactions involving multi-step 16-electron transformations provide higher specific capacity (1672 mAh g−1) and specific energy (2600 Wh kg−1), exhibiting great potential in the field of energy storage. However, the inherent insulation of sulfur, slow electrochemical reaction kinetics and detrimental shuttle-effect of lithium polysulfides (LiPSs) restrict the development of LSBs in practical applications. Herein, the iodine-doped carbon nanotubes (I-CNTs) is firstly reported as sulfur host material to the enhance the adsorption-conversion kinetics of LSBs. Iodine doping can significantly improve the polarity of I-CNTs. Iodine atoms with lone pair electrons (Lewis base) in iodine-doped CNTs can interact with lithium cations (Lewis acidic) in LiPSs, thereby anchoring polysulfides and suppressing subsequent shuttling behavior. Moreover, the charge transfer between iodine species (electron acceptor) and CNTs (electron donor) decreases the gap band and subsequently improves the conductivity of I-CNTs. The enhanced adsorption effect and conductivity are beneficial for accelerating reaction kinetics and enhancing electrocatalytic activity. The in-situ Raman spectroscopy, quasi in-situ electrochemical impedance spectroscopy (EIS) and Li 2 S potentiostatic deposition current–time (i-t) curves were conducted to verify mechanism of complex sulfur reduction reaction (SRR). Owing to above advantages, the I-CNTs@S composite cathode exhibits an ultrahigh initial capacity of 1326 mAh g−1 as well as outstanding cyclicability and rate performance. Our research results provide inspirations for the design of multifunctional host material for sulfur/carbon composite cathodes in LSBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyurethane elastomer (TPU) is designed firstly as a solid polymer electrolyte (SPE) for LMBs. • Soft chain forging PEO and hard chain segments IPDI enhance Li+ conductivity, elastic modulus and flexibility of the SPE. • The Li 2 S additive promotes in-situ generatation of LiF at the Li/PEO interface. • Smooth and stable interface enables Li symmetric battery a long cycle of 1400 h at 0.1 mA/cm2. • The Li||LiFePO 4 cell exhibits an excellent capacity retention rate of 80% after 500 cycles at 1C. Li metal anodes have high specific capacity and low electrode potential, and have always been considered as one of the most promising anode materials. However, the growth of Li dendrites, unstable solid electrolyte interface layer (SEI), severe side reactions at the Li/electrolyte interface, and infinite volume expansion of the Li anode seriously hinder the practical application of solid-state Li metal batteries (LMBs). Herein, we report a polyurethane elastomer (TPU) material with high elasticity and interfacial stability as a solid polymer electrolyte (SPE) for LMBs. The synergistic effects of its designed soft chain forging (PEO) and hard chain segments (IPDI) can enhance Li ion conductivity, elastic modulus and flexibility of the SPE to settle the challenges of the Li metal anodes. Moreover, Li 2 S, as a solid-state electrolyte additive, is able to effectively inhibit the occurrence of side reactions at the interface between Li metal and SPE, promote the decomposition of N(CF 3 SO 2) 2 − and in-situ generation of LiF with low Li+ diffusion barrier and excellent electronic insulation, achieving rapid Li ion transport and uniform Li deposition. As a result, stable cycle of up to 1400 h has been achieved for a Li||TPU-Li 2 S||Li battery at 0.1 mA/cm2 at 50 ℃, accompanied with a stable cycling performance of 350 h at a higher current density of 0.5 mA/cm2. Finally, the LiFePO 4 ||TPU-Li 2 S||Li full battery exhibits an excellent cycling performance with a capacity retention rate of 80 % after 500 cycles at 1C. This simple and low-cost strategy provides novel design thoughts for practical application of high-performance SPEs in stable and long-life LMBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyurethane elastomer (TPU) is prepared firstly as an artificial SEI of Li metal anode. • IPDI hard chain segment and soft link forging PEO jointly improve elasticity and ion conducting channel of the TPU. • TPU coated Li foil can be stable in air for 45 min without obvious deterioration. • The elastic modulus of TPU is up to 105 Pa and the elongation at break is up to 2854%. • TPU-Li||LFP cell delivers a long cyclelife with 90% retention after 1500 cycles at 5 C. Compared with other anode materials, Li metal anode has higher capacity density and lower electrode potential, which has been considered as one of the most promising anode materials. However, the unstable solid electrolyte interface (SEI) leads to Li dendrite growth and the infinite volumetric expansion of Li metal, which seriously hinders the stability and cycle life of Li metal batteries (LMBs). Here, a polyurethane elastomer (TPU) material with high elasticity and air stability is used as the artificial SEI of Li metal anode. Its designed synergistic effect of soft chain forging and hard chain segments not only gives TPU artificial SEI layer good electronic insulation, Li ion conductivity, Li dendrite growth inhibition, high elastic modulus and flexibility to adapt to Li volume expansion, but also has a significant air protection effect on the Li metal surface, so that the TPU coated Li foil will not occur obvious oxidation phenomenon after being placed in air for 45 min. The Li symmetric battery modified by TPU achieved a stable and long-term cycle performance of 1300 h at 1 mA/cm2, it can also cycle stably at a high current density of 10 mA/cm2. The Coulomb efficiency of the modified Li/Cu half-cell maintains at above 97% after 400 cycles. In addition, the full cell with LiFePO 4 cathode also delivers a very excellent long cycle stability with 90% capacity retention after 1500 cycles at 5 C. This surface modification strategy of SEI on lithium anode has has great research value and will help to improve the widely application of LMBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional polymer electrolyte (MPE) buffer layer is constructed on LLZTO surface through an in-situ crosslinking strategy. • MPE improves interface contact at both sides of LLZTO and widen electrochemical window. • MPE@LLZTO facilitates uniform Li+ deposition/exfoliation and inhibits dendrite growth. • The Li symmetrical and NCM523 full cells exhibit excellent cycle performance at 30 °C. The garnet Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 (LLZTO) is one of the most promising electrolytes for commercial application since of its high ionic conductivity and good stability to Li. Nevertheless, the poor electrolyte/electrode interface contact enlarges the interface impedance of all-solid-state battery (ASSB). Herein, a multifunctional polymer electrolyte (MPE) interface buffer layers are formed on both sides of LLZTO surface through an in-situ crosslinking strategy to improve the interface contact with electrodes, which can facilitate uniform Li+ deposition/exfoliation and inhibit the growth of lithium dendrites as evidenced by the reduced interface impedance (103.4 Ω cm2), the increased critical current density (CDD, 1.2 mA cm−2) and 950 h stable cycle of Li symmetric cells at 0.7 mA cm−2, 0.7 mA h cm−2. Besides, the MPE layer can reduce the magnitude of electric field at the interface and widen the electrochemical window (0∼5.2 V). The stable interface of the LLZTO@MPE/cathode enables the full cells matching with the LiFePO 4 (LFP) and LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) cathodes to deliver superior electrochemical performances. Specifically, the Li/MPE@LLZTO@MPE/LFP delivers a capacity retention rate of 87% after 200 cycles at 1 C. When it's matched with the NCM523 cathode, a capacity retention rate of 98% is retained after 100 cycles at 1 C. This work provides an effective and simple way to build good-interface-contact and long-lifespan garnet solid-state lithium metal batteries (SSLMBs). [ABSTRACT FROM AUTHOR]

• Heterostructured Mn 2 SnO 4 /SnO 2 @spherical graphene composite is reported. • Mn 2 SnO 4 /SnO 2 nanoheterostructures are sandwiched between spherical graphene shells. • Mn infiltration promotes SnO 2 dissolution-redeposition and heterostructure formation. • Heterostructures produce internal electric field to improve Li+ transport kinetics. • The difference between Mn 2 SnO 4 /SnO 2 @SG and SnO 2 @SG was compared and discussed. Sn-based metal oxides and composites have been widely investigated as candidate anodes for lithium-ion batteries. However, continuous capacity fade caused by serious volumetric expansion and crystal pulverization is often noticed during lithiation and alloying processes. In this study, we design a novel heterogeneous structural composite by constructing sandwich-structured graphene hollow spheres limited Mn 2 SnO 4 /SnO 2 heterostructures (Mn 2 SnO 4 /SnO 2 @SG), of which infiltration of Mn source promotes the dissolution-redeposition of SnO 2 in hollow-spherical graphene (SnO 2 @SG) and their in-situ transformation into Mn 2 SnO 4 ; and the uniform distributed Mn 2 SnO 4 and SnO 2 nanoparticles are adjacent each other to form heterostructure within the sandwiched graphene hollow spheres. By comparing with the single metal oxide SnO 2 @SG material, the influence of the microstructure, chemical composition, element valence state and electrochemical properties of the heterostructured Mn 2 SnO 4 /SnO 2 @SG is investigated. The results show that the construction of Mn 2 SnO 4 /SnO 2 heterostructure dramatically improves electronic/ionic transport kinetics and increases lithium storage reversibility, therefore leading to distinctly superior rate capability (823.8 mAh g−1 at 5 C) and cycling capacity. An ultra-high discharge capacity of 1180.4 mA h g−1 is maintained up to 100 cycles at 100 mA g−1. The promising electrochemical performances can be attributed to the sandwiched-structure hollow graphene spherical skeleton and the formation of unique Mn 2 SnO 4 /SnO 2 heterostructures. [ABSTRACT FROM AUTHOR]