Safety, high-performing and effects of the N/P ratio of a solid lithium ion battery using PEGDME based polymer electrolytes

Abstract

In this study, we report on the electrochemical properties of a solid state lithium ion battery (LIB) using a poly (ethylene glycol) dimethyl ether (PEGDME)-based solid polymer electrolyte (P-SPE). The LIB is prepared using a LiFePO4 (LFP) cathode and graphite anode material with P-SPE, and the kinetic properties of the lithium ions in the P-SPE are investigated. The synthesized P-SPE is shown to be suitable solid polymer electrolyte candidate for LIB applications. LFP and graphite are selected as electrode materials to validate their effectiveness in different battery cells with respect to their high energy density and inherent safety. The five-layer stacked 5 × 6 cm2 pouch-type LIB demonstrates a high capacity of 90 mAh (0.6 mAh/cm2) or more in the initial cycle, and it shows cycle stability with a capacity decrease of 20% over 500 cycles. We test the manufactured pouch-type full cells under extreme conditions (e. g., cutting, crushing and exposure of the battery cell to the atmosphere). LIBs using the developed P-SPE are promising solid polymer electrolyte candidates for wearable LIB as well as high energy LIB applications.

Keywords

• Solid polymer electrolyte
• Pouch-type
• Full cell
• N/P ratios
• Wearable LIB