Highly ionic conducting methacrylic-based gel-polymer electrolytes by UV-curing technique

Abstract

Today, special interest is focused on polymer systems showing high ionic conductivity at ambient and/or sub ambient temperatures, since they find unique practical applications, such as separators in high power, versatile, rechargeable Li-based batteries. Thermo-set membranes prepared by free radical photo polymerisation (UV-curing) could be an interesting alternative to existing polymer electrolytes. In the present paper, we report the application of this technique to the synthesis of gel-polymer membranes which can be used as electrolytes for lithium battery application. These membranes are prepared by mixing a dimethacrylic (BEMA) and/or a diacrylic monomer (PEGDA), a methacrylic reactive diluent (PEGMA) and a radical photo-initiator with the in situ addition of a EC/DEC solution. The above mixtures are UV irradiated to obtain transparent, flexible, easy to handle gel-polymer films. The gel-polymer electrolytes (GPEs) are then prepared by swelling these membranes in different liquid electrolytes. The results obtained indicate some superior and satisfactory performances in terms of ionic conductivity at ambient temperature for various GPEs prepared with different lithium salt solutions. The relevance of these features in view of practical application is here demonstrated by the response of lithium cells based on prepared GPEs.

All-solid-state lithium-based polymer cells for high-temperature applications

“…Poly(ethylene glycol) methyl ether methacrylate (PEGMA-1100, average M n =1,100, Aldrich) was used as reactive diluent which can control the cross-linking density during the polymerisation reaction [26,28]. A siloxane diacrylate monomer (SAC, Coatosil 3509, avg.…”

“…Materials have been chosen which have suitable stability towards lithium over a sufficiently long period of time and high decomposition voltages. Compared to the earlier methods described in some previous works regarding the preparation of plasticised polymer electrolytes [26][27][28][29][30], these SCPE membranes do not contain any kind of organic solvent. This avoids important drawbacks, such as solvent volatility and leakage, poor mechanical property at high degree of plasticization, and reactivity of polar solvents with the lithium electrode.…”

Fast Switching Electrochromic Devices Containing Optimized BEMA/PEGMA Gel Polymer Electrolytes

“…In the present work, we developed an optimized gel polymer electrolyte membrane which can work at the same time as separator, electrolyte, and glue keeping the EC device together (see Figure 2). A polymer-based electrolyte similar to that chosen for this work was previously developed for the application in Li-ion cells [16,21,22]. The same knowledge and experience were used to study the feasibility of such materials to obtain reliable ECDs with reduced switching times.…”

Synthesis and Properties of a Photopatternable Lithium‐Ion Conducting Solid Electrolyte

“…[9,10] Research related to photopatternable solid electrolytes has largely focused on polymers that can be cross-linked in the presence of UV radiation. [11][12][13][14] However, these studies have not demonstrated the ability to pattern solid electrolytes directly on electrodes.SU-8 is an epoxy-based negative photoresist that is used in the fields of semiconductors, microfluidics, and MEMS due to its spatial resolution at the sub-30 nm level and ability to pattern high aspect-ratio structures. [15,16] In this study, we demonstrate that SU-8 can be modified to become a gel electrolyte.…”

“…[9,10] Research related to photopatternable solid electrolytes has largely focused on polymers that can be cross-linked in the presence of UV radiation. [11][12][13][14] However, these studies have not demonstrated the ability to pattern solid electrolytes directly on electrodes.…”