Morphological, rheological and electrochemical studies of Poly(ethylene oxide) electrolytes containing fumed silica nanoparticles

Abstract

TitleMorphological, rheological and electrochemical studies of poly(ethylene oxide) electrolytes containing fumed silica nanoparticles Permalink https://escholarship.org/uc/item/2290j937

Preparation and characterization of composite electrolytes based on PEO(375)-grafted fumed silica

“…The long annealing that is needed may be due to the persistence of order in PEO even in the molten state [54]. The importance of annealing temperatures and thermal cycling has been previously reported [29]. For (PEO) 8 -LiBF 4 with 20 wt.% Al 2 O 3 , annealing at 175°C for 2 h completely suppressed crystallization [31].…”

“…Very little improvement in conductivity was observed for completely amorphous PEO-based electrolytes (O/Li = 8/1), except upon addition of large amounts of PEO(500). All of the completely amorphous films were of poor quality, and addition of SiO 2 or PEO (375)-SiO 2 never resulted in self-supporting material, although the addition of SiO 2 has been shown to increase the modulus [29].…”

“…Addition of ceramic fillers (TiO 2 [17][18][19][20][21][22][23][24], SiO 2 [25][26][27][28][29], Al 2 O 3 [17,18,21,28,[30][31][32][33], K-LiAlO 2 [34][35][36], BaTiO 3 [37,38], MgO [38,39]) to PEO-based electrolytes was claimed to increased RT conductivities by about 2-3 orders of magnitude, increased lithium ion transference numbers, and also improved interfacial [37] as well as mechanical properties [40]. Ion transport properties, thermal transitions and morphology of the composite electrolytes have been shown to depend on the size/mass [31,39] (nano better than micron), surface area and surface nature (acidic/basic/type of surface groups) of the ceramic fillers.…”

Exploration on nano-composite fumed silica-based composite polymer electrolytes with doping of ionic liquid

“…The addition of filler inhibits the degree of polymer segmental mobility by forming the nano-particles boundaries. Since the polymer chains can only be arranged to ordered arrangement to yield the crystalline structure through segmental movement, hence the adulteration of SiO 2 increases the amorphous region by restricting the polymer segmental mobility [17].…”

Fillers for Solid-State Polymer Electrolytes: Highlight

“…14,22 However, in fact, the role of ceramic fillers seems to be quite different from that of liquid plasticizers, which significantly change the dynamics of polymer chain and thus promote the segmental conductivity. 23,24 In contrast, the T g values of the PEO-based electrolyte systems were not noticeably changed by the addition of ceramic fillers, preserving the initial amorphous structures. Lewis acid-base type interactions between filler surface groups and cations/ anions appear to be responsible for conductivity enhancement (acidic > basic > neutral > weakly acidic).…”