The development of solid-state lithium-oxygen batteries is currently limited primarily by the high solid-solid interfacial resistance and the lack of efficient assembly of electrolyte and electrode. In this work, noncovalent interactions between the cations of an ammonium ionic liquid and both solid electrolytes and carbon air cathodes are introduced. The ionic liquid-based electrolytes (ILE) are solidified on Li 6·40 La 3 Zr 1·40 Ta 0·60 O 12 (LLZTO) nanoparticles and gelated by multi-wall carbon nanotubes (MWCNTs), respectively, to construct LLZTO@ILE quasi-solid-state electrolyte (QSSE) and MWCNTs-LLZTO/ILE gel cathode (GC). The QSSE exhibits a high ionic conductivity of 1.71 × 10 −3 S cm −1 at 60 °C, high Li-ion transference number of 0.56, broad electrochemical window of ~4.8 V and good thermal stability . The GC shows outstanding compatibility with QSSE. Quasi-solid-state Li–O 2 batteries are assembled by integrating QSSE and GC films with a facile roll forming method, showing a low total interfacial resistance (~87 Ω cm 2 ), and excellent reversible cycles (70 cycles) with low charge overpotential (<0.44 V) and quite high electrical energy efficiency (>70%) at 60 °C and 200 mA g −1 . A 0.12 Ah pouch-type Li–O 2 battery was achieved by this method. These results suggest that the noncovalent interactions initiated by IL cations could be an effective approach to solve the solid-solid interface issue and achieve high discharge capacity in solid-state energy storage devices.
Shidong Song,Dequan Zhang,Yanli Ruan,Limei Yu,Yongqiang Xu,Joykumar Thokchom,Donghai Mei
Heightened attention for solid-state Li–O2 batteries (SSLOBs) exists due to their improved safety, wider electrochemical window, and high energy density in addition to the solid electrolyte’s innate capability of suppressing Li dendrite penetration and shielding the Li metal anode from oxygen, CO2, and moisture in the air, in comparison with the conventional Li–O2 batteries using liquid organic electrolytes. Herein, a cathode supported quasi-SSLOB with an integrated composite polymer-based architecture (ICPA) is developed with reduced interfacial resistance, extended triple-phase boundaries (TPBs) for Li–O2 reactions, and a thin film solid-state electrolyte. The Li–O2 cell with ICPA (denoted as ICPA cell) exhibits a lower charge transfer impedance than its counterpart with the same composite polymer electrolyte (CPE) but a nonintegrated structure (termed the CPE cell). The former shows reduced interfacial impedance between electrolyte and cathode and increased TPBs. Furthermore, the ICPA cell delivers higher discharge capacity, lesser capacity decay, and significantly lower impedance rise after cycles than the CPE cell, ascribed to the continuous Li-ion transport in ICPA and the resulting more efficient discharge and charge processes. Under a limited capacity cycling protocol of 300 mAh g–1, the ICPA cell achieves excellent reversibility for 78 cycles, remarkably surpassing the CPE cell which only performs 44 cycles in addition to showing half of the after-cycle impedance compared to that for the CPE cell. Nonetheless, the same composite polymer electrolyte used for both CPE- and ICPA-based cells demonstrates excellent stability toward Li metal after long-term cycling. These findings manifest that the design and application of cathode supported SSLOB with ICPA can be a promising approach to achieve high-performance Li–O2 batteries.
危险品化学品经营许可证（带存储）