Shingo Kaneko

The application of a water-based hybrid polymer binder to a high-voltage and high-capacity Li-rich solid-solution cathode and its performance in Li-ion batteries

AbstractnUniform cathode films were prepared with a Li-rich solid-solution (Li[Li0.2Ni0.18Co0.03Mn0.58]O2) cathode material and a water-based hybrid polymer binder (TRD202A, JSR, Japan) composed of acrylic polymer and fluoropolymer, carboxymethyl cellulose, and conducting carbon additive. The films exhibited stable charge/discharge cycling performances (average discharge capacity: 260 mAh g−1) when cycled between 4.8 and 2.0xa0V for 80 cycles. After 80 cycles in the chemical environment of Li-ion cells, a cathode film prepared with the water-based hybrid polymer binder showed longer-term reliability as well as higher electrochemical resistance when compared with a cathode film using the conventional polyvinylidene difluoride binder. Additionally, even without electrochemical pretreatment, the Al2O3 coating on the cathode surfaces improved the cycling stability by preventing the cathode surface from making direct contact with H2O.Graphical Abstract

Enhancement of the electrocatalytic oxygen reduction reaction on Pd3Pb ordered intermetallic catalyst in alkaline aqueous solutions

AbstractnEnhancement of the oxygen reduction reaction (ORR) was examined with Pd3Pb ordered intermetallic nanoparticles (NPs) supported on titania (Pd3Pb/TiO2). The Pd3Pb/TiO2 catalyst was synthesized by a conventional wet chemical method with Pd and Pb ion precursors, a reducing agent and TiO2 powder under ambient temperature. X-ray ndiffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy measurements indicated the formation of the ordered intermetallic phase of Pd3Pb in the NP form on the TiO2 surface. Electrochemical measurements showed that the Pd3Pb/TiO2 catalyst markedly enhanced the ORR in an alkaline environment due to the unique surface of Pd3Pb NPs and the strong interaction between Pd3Pb and TiO2 compared with TiO2-supported Pd, Pt, and PtPb NPs. The onset potential of Pd3Pb/TiO2 was shifted toward a higher potential by 110–150xa0mV compared with Pd/TiO2, PtPb/TiO2, and Pt/TiO2.Graphical Abstract