Carbonate-linked poly(ethylene oxide) polymer electrolytes towards high performance solid state lithium batteries

Abstract

A B S T R A C TThe classic poly(ethylene oxide) (PEO) based solid polymer electrolyte suffers from poor ionic conductivity of ambient temperature, low lithium ion transference number and relatively narrow electrochemical window (<4.0 V vs. Li + /Li). Herein, the carbonate-linked PEO solid polymer such as poly (diethylene glycol carbonate) (PDEC) and poly(triethylene glycol carbonate) (PTEC) were explored to find out the feasibility of resolving above issues. It was proven that the optimized ionic conductivity of PTEC based electrolyte reached up to 1.12 Â 10 À5 S cm À1 at 25 C with a decent lithium ion transference number of 0.39 and a wide electrochemical window about 4.5 V vs. Li + /Li. In addition, the PTEC based Li/LiFePO 4 cell could be reversibly charged and discharged at 0.05 C-rates at ambient temperature. Moreover, the higher voltage Li/LiFe 0.2 Mn 0.8 PO 4 cell (cutoff voltage 4.35 V) possessed considerable rate capability and excellent cycling performance even at ambient temperature. Therefore, these carbonate-linked PEO electrolytes were demonstrated to be fascinating candidates for the next generation solid state lithium batteries simultaneously with high energy and high safety.

Composite polymer electrolytes based on electrospun thermoplastic polyurethane membrane and polyethylene oxide for all‐solid‐state lithium batteries

“…Lithium ion batteries have been widely used in electric vehicles, portable devices, drones and other energy storage fields recently due to their higher energy density and the environmental issues . However, commercial lithium ion batteries which use organic solvents as electrolytes suffer from potential safety risks such as combustion, leakage and explosion . Compared to liquid electrolytes, solid polymer electrolytes (SPEs) are safer and have attractive features such as good interfacial stability against lithium anodes and excellent mechanical properties .…”

CO2-sourced polycarbonates as solid electrolytes for room temperature operating lithium batteries

“…The ionic conductivity of PC-3 (3.75 ×10 -5 S.cm -1 at room temperature and 1.86 ×10 -4 S.cm -1 at 60°C) is comparable or even better to those determined for the most efficient polycarbonate-based SPEs. 15,20,21,22,2324 DSC curves of the three SPEs are shown in Figure 2b. All PCs were plasticized by LiTFSI, resulting in SPEs with suppressed or decreased melting temperature .…”

Mechanically Stable UV‐Crosslinked Polyester‐Polycarbonate Solid Polymer Electrolyte for High‐Temperature Batteries

“…The most studied polymeric systems for solid‐state batteries are based on poly(ethylene oxide) (PEO), but much research is also being done on alternative polymer systems with attractive properties which PEO lacks, such as amorphicity and high transference numbers . Recent introductions of carbonyl‐coordinating polymers such as poly(ethylene carbonate) (PEC), poly(trimethylene glycol carbonate) (PTEC), and more have resolved some of the issues of the PEO‐based electrolyte systems. Recent studies within our group have, for example, been conducted on the fully amorphous copolymer poly(ϵ‐caprolactone‐ co ‐trimethylene carbonate) (poly(CL‐ co ‐TMC)), which shows both good ionic conductivity at ambient temperature and high lithium transference number …”