Quasi-Solid-State Rechargeable Li–O₂ Batteries with High Safety and Long Cycle Life at Room Temperature

Abstract

As interest in electric vehicles and mass energy storage systems continues to grow, Li-O batteries are attracting much attention as a candidate for next-generation energy storage systems owing to their high energy density. However, safety problems related to the use of lithium metal anodes have hampered the commercialization of Li-O batteries. Herein, we introduced a quasi-solid polymer electrolyte with excellent electrochemical, chemical, and thermal stabilities into Li-O batteries. The ion-conducting QSPE was prepared by gelling a polymer network matrix consisting of poly(ethylene glycol) methyl ether methacrylate, methacrylated tannic acid, lithium trifluoromethanesulfonate, and nanofumed silica with a small amount of liquid electrolyte. The quasi-solid-state Li-O cell consisted of a lithium powder anode, a quasi-solid polymer electrolyte, and a PdCo/multiwalled carbon nanotube cathode, which enhanced the electrochemical performance of the cell. This cell, which exhibited improved safety owing to the suppression of lithium dendrite growth, achieved a lifetime of 125 cycles at room temperature. These results show that the introduction of a quasi-solid electrolyte is a potentially new alternative for the commercialization of solid-state Li-O batteries.

3D Coral-like LLZO/PVDF Composite Electrolytes with Enhanced Ionic Conductivity and Mechanical Flexibility for Solid-State Lithium Batteries

“…With the ever-growing demands of high energy-density storage systems in portable electronic devices and electric vehicles, the lithium metal has been received as an ideal anode electrode in lithium batteries because of its high theoretical capacity (3860 mA h g –1 ), lowest redox potential (−3.04 V vs SHE), and low density (0.59 g cm –3 ). − Unfortunately, the traditional liquid electrolytes cannot afford the use of a lithium-metal anode in a battery because of the severe safety issues derived from the electrolyte decomposition and dendrite growth that could transpierce the separators and cause the battery short circuit or even thermal runaway. − Replacing the liquid electrolytes with the solid-state electrolytes (SSEs) in lithium-metal batteries is anticipated as a most promising way to fundamentally eliminate the safety concerns. − More importantly, owing to the wide electrochemical stability window of SSEs, a high-voltage cathode could also be coupled with the lithium-metal anode to achieve high energy density.…”

Component‐Interaction Reinforced Quasi‐Solid Electrolyte with Multifunctionality for Flexible Li–O2 Battery with Superior Safety under Extreme Conditions

“…It can be seen from Figure a that the sample with the optimized content of SiO 2 (20 wt%) reaches the maximum ionic conductivity of 0.93 mS cm −1 , which is comparable to the value for a GF‐based liquid electrolyte system (1.05 × 10 −3 S cm −1 ), and thus indicates good Li + ionic conductivity. The SiO 2 filler used as electrolyte dissociation promoter and solid plasticizer is also responsible for the enhanced ionic conductivity of the polymer based electrolyte . As is well known, high crystallinity of the polymer matrix is a main issue that is responsible for lowering the ionic conductivity of a polymer based electrolyte .…”

Building Better Batteries in the Solid State: A Review

“…PEGMA can be used as an ion-conducting agent in Li-O 2 batteries. By coupling with methacrylated tannic acid (MTA), which acts as a cross-linker, and nanofumed silica, which is a filler, a polymer composite electrolyte was obtained [416]. This composite achieved a remarkable ionic conductivity of 0.14 × 10 −3 S cm −1 at room temperature, which was not only attributed to the SiO 2 , but also because of the small amount of MTA, which allowed polymerization and cross-linking of PEO derivatives into free-standing films despite the short chain lengths of EO.…”