Tissue paper-based composite separator using nano-SiO2 hybrid crosslinked polymer electrolyte as coating layer for lithium ion battery with superior security and cycle stability

Abstract

With the development of energy-storage devices, separator is encountered by several challenges including adequate safety, higher current density and superior stability. Tissue paper, composed of packed cellulose bers, possesses lower production cost, more easily accessibility, superior wettability and outstanding thermostability, thus being prospective as a substrate of high performance separator. To address structure collapse phenomenon occurred in conventional coating layer after long term electrolyte swelling, nano-SiO 2 hybrid crosslinked network was constructed on tissue paper through chemical reactions between polymer poly (vinylidene uoride-co-hexa uoropropylene) (PVDF-HFP) and hyperbranched polyethyleneimine (PEI) in this work. The in uences of crosslinking degree on physical properties and electrochemical performance were studied thoroughly. It can be found that when the crosslinking ratio of PVDF-HFP and PEI xed at 10:1, the crosslinked composite separator displays excellent electrolyte uptake and wettability, superior ionic conductivity, better interfacial compatibility as well as higher Li + transference number (0.56), thus offering battery with prominent rate capabilities.Besides, this crosslinked composite separator exhibits satisfying dimensional stability even treated at 250 o C, better ame retardancy, enhanced mechanical behavior, wider electrochemical window and outstanding cycle stability. Accordingly, tissue paper-based crosslinked composite separator can meet higher requirements put forward by high power lithium ion battery. HighlightsTissue paper was employed to fabricate lithium ion battery separator.Nano-SiO 2 hybrid crosslinked polymer electrolyte was constructed to modify tissue paper.The composite separator gave superior electrochemical performance and prominent rate capabilities.The designed coating layer was con rmed to increase mechanical strength, broaden electrochemical window and maintain cycle stability obviously.Excellent thermal stability and certain self-extinguishing were obtained for composite separator to afford security.

A Light-Thin Chitosan Nanofiber Separator for High-Performance Lithium-Ion Batteries

“…The Li + transfer number of Li/CME/Li batteries was 0.5 and 0.49, respectively, and was higher than the Celgard separator (0.26) and CM25 separator (0.2), which demonstrated that the mobility of solvated anions was restricted in the solvent channels of CME separators. This is due to two reasons: (1) the PF 6 ions were physically suppressed by the three-dimensional network of CME separators [55]; (2) the electrolyte anions (PF 6 ) as a Lewis acid were trapped by the Lewis base (-NH2), allowing more Li + to migrate during the charge/discharge process [56]. This further verifies the influence of -NH2 on anion transport in the chitosan fiber separators.…”

Porous Sodium Alginate/Boehmite Coating Layer Constructed on PP Nonwoven Substrate as a Battery Separator through Polydopamine‐Induced Water‐Based Coating Method

“…Interfacial compatibility between separator and lithium electrode is another factor to decide ohmic polarization in LIB, [43] which can be judged from interfacial impedance plots of Li/separator/Li cell as shown in Figure 7(b). We could find two semicircles located at medium and low frequency regions, which were respectively attributed to solid electrolyte interface film impedance ( R SEI ) and charge transfer impedance ( R ct ) [44] .…”

Cross-Linked Polymer Composite Electrolyte Incorporated with Waste Seashell Based Nanofiller for Lithium Metal Batteries

“…The effective strategy to improve the electrochemical performance with stable mechanical stability is the addition of inert metal oxide fillers to the polymer matrix. Especially the incorporation of inorganic oxide fillers, such as TiO 2 , SiO 2 , ZrO 2 , Al 2 O 3 , and BN etc ., has an impactful increase in amorphous nature with the addition of an appropriate amount in polymer electrolyte. The inert inorganic oxide fillers dispersed in polymer solution are a better influencing agent in retaining the amorphous nature, which transfers the lithium ions under segmental motion in polymer electrolyte. , Nevertheless, preparing these inorganic fillers requires huge costs with profound preparation techniques such as solid-state, sol–gel, sputtering, chemical vapor deposition, etc.…”