High performance composite solid polymer electrolyte systems for electrochemical cells

• Published in: Journal of power sources 2013-12, Vol.244, p.287-293
• Main Authors: Wu, G.M., Lin, S.J., Yang, C.C.
• Format: Article
• Language: English
• Subjects: Applied sciences; Battery discharge capacity; Composite; Density; Direct energy conversion and energy accumulation; Discharge; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical cells; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrolytes; Exact sciences and technology; Ionic conductivity; Materials; Non-woven; Polyethylenes; Power density; Solid polymer electrolyte; Strength
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2013.01.044

We report high performance composite solid polymer electrolytes for electrochemical cells with comprehensive properties in high mechanical strength and high ionic conductivity. The composite electrolytes consist of porous non-woven polymer filament substrates that are impregnated with high ion-conducting materials. To insure structural integrity, the non-woven polypropylene/polyethylene core–shell substrates are sulfonated to activate the surface. The high ion-conducting materials are prepared from poly(vinyl alcohol) with the incorporation of acrylic acid monomer and cross-linking agent. The results show well-balanced physical and electrochemical characteristics that warrant excellent battery discharge capacity and cell power density. The room temperature ionic conductivity is high at 0.16–0.21 S cm−1, and the activation energy is low at 0.5 kJ mol−1. The mechanical strength is improved to 12 MPa with good elongation at 58–62%. The anionic transport numbers (t−) are in the range of 0.93–0.99 in 1 M KOH, 0.91–0.97 in 1 M NaOH, and 0.83–0.91 in 1 M LiOH, respectively. The cyclic voltammetric study indicates good stability with symmetric curves between the cathodic and anodic peaks. The fully solid-state metal–air fuel cells exhibit excellent discharge capacity of 1506 mAh and high anode utilization of 95.7%. The power density is achieved at 91 mW cm−2. ► New composite solid polymer electrolytes were developed to exhibit both high ionic conductivity and high mechanical strength. ► The cyclic voltammetry analysis indicated excellent electrochemical stability. ► The solid-state fuel cells showed excellent discharge capacity of 1506 mAh. ► The anode utilization was very good at 95.7%. ► The battery power density has been achieved at 91 mW cm−2.