| 초록 |
Lithium-ion batteries with ever-increasing energy densities are needed for advanced IT devices and all-electric vehicles. To this end, silicon has been spotlighted as a promising anode material due to its superior specific capacity to any other candidates under consideration. Nevertheless, the huge volume change of silicon during repeated charge-discharge cycles limits cycle life via particle pulverization and unstable electrode-electrolyte interface, especially when the particle sizes are in the micrometer range. We show that the incorporation of 5 wt% polyrotaxane molecular pulley to conventional polyacrylic acid binder imparts extraordinary elasticity to the polymer network originating from the ring sliding motion of polyrotaxane molecular pulley. This unique binder combination allows even the pulverized Si particles to remain coalesced without disintegration, enabling stable cycle life for silicon microparticle anodes (~2.1 μm) at commercial-level areal capacities. |
