Flexible Electrodes and Electrolytes for Energy Storage

Abstract

The advent of flexible, wearable electronics has placed new demands on energy storage systems. The demands for high energy density achieved through the use of highly conducting materials with high surface area that enable facile electrochemical processes must now be coupled with the need for robustness and flexibility in each of the components: electrodes and electrolytes. This perspective provides an overview of materials and fabrication protocols used to produce flexible electrodes and electrolytes. We also discuss the key challenges in the development of high performance flexible energy storage devices. Only selected references are used to illustrate the myriad of developments in the field.

Progress in polymeric separators for lithium ion batteries

“…The large-sized pores would cause internal short circuit, overgrowth of lithium dendrite, self-discharge, and further deteriorate the battery cycle performances and safety. glass-microfiber/PVA-β-CN LiTFSI-EC/DMC -0.89 [161] PP/PVDF LiPF 6 -EC/DMC 116 0.65 [79] PP/PVDF-HFP/PMMA LiPF 6 -EC/DMC 212 1.85 [162] PI/PEG LiPF 6 140 1.45 [163] PVDF/PEGDA LiPF 6 -EC/DMC -3.3 [164] PET/PVDF-HFP LiPF 6 -EC/DEC -0.86 [2] PET/PVA-co-PE LiPF 6 -EC/DMC 160 0.55 [165] PE/P(AN-Vac) LiPF 6 -DMC/DEC/EC 380 3.8 [166] TPU/PVDF LiClO 4 -EC/PC 342 3.2 [167] PVDF-PVC LiClO 4 -PC/EC 290 2.25 [168] PVDF-10CTFE PBT LiPF 6 -EC/EMC -0.27 [176] cellulose LiPF 6 -EC/DEC 0.77 [177] cellulose/PSA LiPF 6 -EC/DEC 260 1.2 [178] PI-PEO LiPF 6 -EC/PC/DMC/ EA 178 0.65 [159] Carboxymethyl cellulose LiPF 6 -EC/DMC 340 1.75 [179] PPESK LiPF 6 -EC/DMC 1210 3.79 [180] Degussa has developed a series of Separion (a trade name) separator by coating a porous ceramic layer on each side of a flexible perforated non-woven separator as illustrated in Fig. Table 6 shows the properties of some non-woven microporous separators.…”

Flexible Carbon Aerogels

“…The flexibility of energy storage devices enables forming, shaping, and mechanical stability of the components of electronic tools [26]. Due to high interest in flexible electrode materials and new demands on energy storage systems [27], an improvement to provide flexible carbon aerogels is of great importance. In the present paper, we report our studies on the carbonization of flexible RF aerogels.…”

A “Tandem” Strategy to Fabricate Flexible Graphene/Polypyrrole Nanofiber Film Using the Surfactant-Exfoliated Graphene for Supercapacitors

“…It has demonstrated excellent electrochemical properties in batteries or supercapacitors [3][4] . The growing market for flexible electronics, such as flexible displays 5 , bendable smart phones, electronic skins 6 and implantable medical devices 7 , requires the development of flexible power sources [8][9] and consequently flexible electrodes. The unique structure of graphene sheets, two-dimension with a high aspect ratio, facilitates the fabrication of robust freestanding films for direct use as flexible electrodes eliminating the dead weight or volume from current collectors or additives used in common electrodes [10][11] .…”