RESUMEN
The accelerated formation of lithium dendrites has considerably impeded the advancement and practical deployment of all-solid-state lithium metal batteries (ASSLMBs). In this study, a soft carbon (SC)-Li3N interface layer was developed with both ionic and electronic conductivity, for which the in situ lithiation reaction not only lithiated SC into LiC6 with good electronic/ionic conductivity but also successfully transformed the mixed-phase Li3N into pure-phase ß-Li3N with a high ionic conductivity/ion diffusion coefficient and stability to lithium metal. The mixed conductive interface layer facilitates fast Li+ transport at the interface and induces the homogeneous deposition of lithium metal inside it. This effectively inhibits the formation of lithium dendrites and greatly improves the performance of the ASSLMB. The ASSLMB assembled with the SC-Li3N interface layer exhibits high areal capacity (15 mA h cm-2), high current density (7.5 mA cm-2), and long cycle life (6000 cycles). These results indicate that this interface layer has great potential for practical applications in high-energy-density ASSLMBs.
RESUMEN
All-solid-state batteries (ASSBs) working at room and mild temperature have demonstrated inspiring performances over recent years. However, the kinetic attributes of the interface applicable to the subzero temperatures are still unidentified, restricting the low-temperature interface design and operation. Herein, a host of cathode interfaces are constructed and investigated to unlock the critical interface features required for cryogenic temperatures. The unstable interface between LiNi0.90Co0.05Mn0.05O2 (Ni90) and Li6PS5Cl (LPSC) sulfide solid electrolyte (SE) results in unfavorable cathode-electrolyte interphase (CEI) and sluggish lithium-ion transport across the CEI. After inserting a Li2ZrO3 (LZO) coating layer, the activation energy of the Ni90@LZO/sulfide SE interface can be reduced from 60.19 kJ mol-1 to 41.39 kJ mol-1 owing to the suppressed interfacial reactions. Through replacing the LPSC SE and LZO coating layer by the Li3InCl6 (LIC) halide SE, both a highly stable interface and low activation energy (25.79 kJ mol-1) can be achieved, thus realizing an improved capacity retention (26.9%) at -30 °C for the Ni90/LIC/LPSC/Li-In ASSB. Moreover, theoretical evaluation clarifies that cathode/SE interfaces with high ionic conductivity and low energy barrier are favorable to the Li+ conduction through the interphase and the Li+ transfer across the cathode/interphase interface. These critical understandings may provide guidance for low-temperature interface design in ASSBs.
RESUMEN
The Li superionic conductor Li3BS3 has been theoretically predicted as an ideal solid electrolyte (SE) due to its low Li+ migration energy barrier and high ionic conductivity. However, the experimentally synthesized Li3BS3 has a 104 times lower ionic conductivity. Herein, we investigate the effect of a series of cation and anion substitutions in Li3BS3 SE on its ionic conductivity, including Li3-xM0.05BS3 (M = Cu, Zn, Sn, P, W, x = 0.05, 0.1, 0.2, 0.25), Li3-yBS2.95X0.05 (X = O, Cl, Br, I, y = 0.05, 0.1) and Li2.75-xP0.05BS3-xClx (x = 0.05, 0.1, 0.15, 0.2, 0.4, 0.6). Amorphous ionic conductor Li2.55P0.05BS2.8Cl0.2 has a high ion conductivity of 0.52 mS cm-1 at room temperature with an activation energy of 0.41 eV. The electrochemical performance of all-solid-state batteries with Li2.55P0.05BS2.8Cl0.2 SEs show stable cycling with a discharge capacity retention of >97% after 200 cycles at 1C under 55 °C.
RESUMEN
Inorganic sulfide solid-state electrolytes, especially Li6PS5X (X = Cl, Br, I), are considered viable materials for developing all-solid-state batteries because of their high ionic conductivity and low cost. However, this class of solid-state electrolytes suffers from structural and chemical instability in humid air environments and a lack of compatibility with layered oxide positive electrode active materials. To circumvent these issues, here, we propose Li6+xMxAs1-xS5I (M=Si, Sn) as sulfide solid electrolytes. When the Li6+xSixAs1-xS5I (x = 0.8) is tested in combination with a Li-In negative electrode and Ti2S-based positive electrode at 30 °C and 30 MPa, the Li-ion lab-scale Swagelok cells demonstrate long cycle life of almost 62500 cycles at 2.44 mA cm-2, decent power performance (up to 24.45 mA cm-2) and areal capacity of 9.26 mAh cm-2 at 0.53 mA cm-2.
RESUMEN
Sulfide solid electrolytes (SEs) are considered to be some of the most promising SEs for commercialization due to their high ionic conductivity, good mechanical ductility, and good interfacial contact with electrodes. The Ohmic resistance of solid-state batteries assembled with sulfide SEs is significantly reduced, but the problem of high interfacial impedance due to poor interfacial chemical/electrochemical stability between sulfide SEs and the electrodes is serious. Therefore, the formation and evolution of the electrode/sulfide SE interface during battery assembly and cycling have a crucial impact on the performance of the battery, which is one of the key issues to be solved in battery commercialization. Herein, a variety of compatible interface protective layers, including PEO and ß-Li3PS4/S, are obtained between sulfide SEs and ether-based room-temperature liquid lithium anodes for long-term stable cycling of >1000 h. Such a technical method for stabilizing the solid-liquid interface between a sulfide SE and an organic liquid lithium anode successfully solves the key problem of interfacial side reactions, making this battery configuration safe and stable for long-cycle operation.
RESUMEN
Sulfide solid electrolytes (SEs) are recognized as one of the most promising candidates for all-solid-state batteries (ASSBs), due to their superior ionic conductivity and remarkable ductility. However, poor air stability, complex synthesis process, low yield, and high production cost obstruct the large-scale application of sulfide SEs. Herein, a one-step gas-phase synthesis method for sulfide SEs with oxide raw materials in ambient air, completely getting rid of the glovebox and thus making large-scale production possible, is reported. By adjusting substituted elements and concentrations, the ionic conductivity of Li4- x Sn1- x Mx S4 can reach 2.45 mS cm-1 , which represents the highest value among all reported moist-air-stable and recoverable lithium-ion sulfide SEs reported. Furthermore, ASSBs with air/water-exposed and moderate-temperature-treated Li3.875 Sn0.875 As0.125 S4 even maintains superior performances with the highest reversible capacity (188.4 mAh g-1 ) and the longest cycle life (210 cycles), which also breaks the record. Therefore, it may become one of the most critical breakthroughs during the development of sulfide ASSBs toward its practical application and commercialization.
