Ionogel-based solid-state supercapacitor operating over a wide range of temperature

Abstract

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Ionogel A B S T R A C TAn inorganic gel polymer electrolyte based on the confinement of an ionic liquid mixture (1:1 by weight or molar ratio) of N-methyl-N-propylpiperidinium bis(fluorosulfonyl)imide (PIP13FSI) and N-butyl-Nmethylpyrrolidinium bis(fluorosulfonyl)imide (PYR14FSI) into a SiO 2 matrix prepared from a sol-gel method was prepared and further used as electrolyte in an all solid-state supercapacitor. The synthetized ionogel exhibits a high ionic conductivity over a wide temperature range (from 0.2 mS cm À1 at À40 C up to 10 mS cm À1 at 60 C). The ionogel-based supercapacitor using two activated carbon electrodes can be operated over 3 V cell voltage window. Moreover this all solid-supercapacitor shows a capacitance up to 90 F g À1 at room temperature. These encouraging results show the interest of developing such devices, including non-toxic and safer electrolytes, packaging issues and flexible devices development.

Flexible and Self-Healing Aqueous Supercapacitors for Low Temperature Applications: Polyampholyte Gel Electrolytes with Biochar Electrodes

“…The specific capacitance of the activated graphene based supercapacitors in ionic liquid electrolyte was ~100 F g −1 at a scanning rate of 1 mV s −1   2 . And specific capacitances of an ionogel-based solid-state supercapacitor were 68 and 34 F g −1 operating at −20 and −40 °C, respectively, at a scanning rate of 5 mV s −1   42 . To our knowledge, a specific capacitance comparable to that of our polyampholyte supercapacitor at subzero temperature has never been reported before in the literature for other aqueous-based electrolyte supercapacitor, or conventional solid-state supercapacitor using PVA-KOH gel or other gels 24 .…”

Ionic Liquids as Environmentally Benign Electrolytes for High‐Performance Supercapacitors

“…For that, [BMPyr][TFSI] was first dissolved in a mixture of MC in DMF that was subsequently removed to form a thin, flexible, self‐standing ion gel containing up to 97 wt% IL. Similarly, a SC using a gel electrolyte and activated carbon electrodes was described by Nègre et al An IL mixture of [BMPyr][FSI] and [MPPip][FSI] was entrapped into a SiO 2 network, forming an ion gel used as electrolyte as well as separator, operated over a 3 V window. This solid‐state SC exhibited a C sp of up to 95 F g −1 at room temperature, due to the filling of the carbon pores by the ions of the gel.…”

A Ceramic‐Based Separator for High‐Temperature Supercapacitors

“…Porous polytetrafluoroethylene (PTFE) films seem to be a promising candidate for HTSC separators, but HTSCs using a PTFE film as separator have been rarely reported to date, probably owing to the low wettability between the PTFE film and electrolyte. Phosphoric acid‐doped polymer, clay‐doped polymer, and SiO 2 ‐doped polymer composites all have been studied as high‐temperature separators but they have the shortcomings of low operation voltage, large thickness, high resistance, and lack of flexibility.…”

“…There are severalt ypes of separators that may be considered for HTSCs, but they all have some shortcomings.C ommercial separators such as polyolefin-based porous films and cellulose paper are not good choicesf or high-temperature applications because they can easily shrink at high temperatures and consequently lead to electrical short circuits inside the devices. [9,20] Although ceramic coatings on polyolefinbased porous films can improve the thermal stability of the separatort osome extent, [20] they still cannot meet the special requirement of HTSCsi nt erms of thermal stability.G lass fiber membranes [14,21,22] have been commonlyu sed as separators for HTSCs because of their outstanding thermal and electrochemical stability,a nd HTSCs fabricated by using glass fiber films exhibit excellentc ycling stability.H owever, the main weaknesso ft he glass fiber membrane was its poor flexibility and relatively low tensiles trength, which impede the fabricationofr olled devices.P orous alumina [18,23] possesses outstanding thermal stability and has also been studied as as eparator of HTSCs, but it is extremely brittle and expensive.P orous polytetrafluoroethylene (PTFE) films seem to be ap romising candidate for HTSC separators,b ut HTSCs using aP TFE film as separator have been rarely reported to date, [24] probably owing to the low wettabilityb etween the PTFE film and electrolyte.P hosphoric acid-doped polymer, [8,10,11] clay-doped polymer, [9] and SiO 2 -dopedp olymer composites [12,25] all have been studied as high-temperature separators but they have the shortcomings of lowo peration voltage,l arge thickness,h igh resistance,a nd lack of flexibility.…”