A Novel Material for High‐Performance Li–O₂ Battery Separator: Polyetherketone Nanofiber Membrane

Abstract

The properties of separators significantly affect the efficiency, stability, and safety of the lithium‐based batteries. Therefore, the improvement of the separator material is critical. Polyetherketone (PEK) has excellent general properties, such as mechanical strength, chemical stability, and thermal stability. Thus, it is expected to be an optimal separator material. However, its low solubility‐induced poor processibility makes it difficult to be used for nanoscale product manufacturing. In this work, the soluble precursor polymer is prepared by introducing a “protecting” group into monomer, and fabricated into nanofiber membrane, which can be converted into polyetherketone nanofiber membrane by a simple acid treatment. The membrane prepared by this chemical‐induced crystallization method exhibits superior chemical, thermal stability, and mechanical strength. Li–O2 batteries with the fabricated membrane as separator have a high cycling stability (194 cycles at 200 mA g−1 and 500 mAh g−1). This work broadens the application field of PEK and provides a potential route for battery separators.

Engineering Triple‐Phase Interfaces around the Anode toward Practical Alkali Metal–Air Batteries

“…A separator is a permeable membrane placed between the cathode and the anode in LABs, used to prevent internal short circuits of cells while allowing smooth transportation of ionic charge carriers. [169] Conventional separators in LABs are porous polymeric membranes such as polyethene (PE) or polypropylene (PP), incapable of suppressing the crossover of atmospheric gases and corrosive RMs from the cathode side. [57,58,170,171] In recent years, hazardous gases/RMs-blocking functional separators have been exploited to protect the Li anode in LABs.…”

Constructing Rechargeable Solid‐State Lithium‐Oxygen Batteries

“…Sun et al developed a soluble precursor polymer by incorporating a "protective" group into the monomer. [106] This precursor polymer was then converted into a nanofiber membrane through a simple acid treatment process, ultimately resulting in a polyether-ketone nanofiber membrane. The membrane prepared by this chemically induced crystallization method exhibited high cycle stability, which circulates 194 times under 200 mA g À 1 with curtailing capacity of 500 mAh g À 1 .…”

“…Sun et al. developed a soluble precursor polymer by incorporating a “protective” group into the monomer [106] . This precursor polymer was then converted into a nanofiber membrane through a simple acid treatment process, ultimately resulting in a polyether‐ketone nanofiber membrane.…”

A 3D-printed framework with a gradient distributed heterojunction and fast Li+conductivity interfaces for high-rate lithium metal anodes

“…Nevertheless, some problems related to lithium metal anodes prevent their practical applications, such as low coulombic efficiency and uncontrollable lithium dendrite growth. 1–5…”

“…Nevertheless, some problems related to lithium metal anodes prevent their practical applications, such as low coulombic efficiency and uncontrollable lithium dendrite growth. [1][2][3][4][5] A variety of approaches have been proposed to mitigate the security risks posed by the above issues, for instance, constructing 3D collectors, modifying the separator, adding additives to the electrolyte and utilizing a solid state electrolyte. [6][7][8][9] The construction of 3D collectors for suppressing lithium dendrites presents unique features.…”