Flexible All-Solid-State Li-Ion Battery Manufacturable in Ambient Atmosphere
A flexible all–solid–state battery possesses competitive electrochemical performance and mechanical stability has been realized by easy manufacture processes using carbon nanotube (CNT) enhanced phosphate electrodes of LiTi2(PO4)3 and Li3V2(PO4)3 and a highly conductive solid polymer electrolyte made of polyphosphazene/PVDF–HFP/LiBOB. The components were chosen based on the systematic manufacturability and (electro–)chemical matching in order to ensure ambient atmosphere battery assembly and to reach high flexibility, good safety, effective interfacial contacts, and high chemical and mechanical stability for the battery while operating. The high energy density of the battery was enabled by a novel design of the self–standing electrodes in a way that a large number of active particles are embedded in the CNT bunches and on the surface of CNT fabric, without binder additive, additional carbon or large metallic current collector. The prepared flexible all-solid-state battery exhibited good rate capability, and more than half of its theoretical capacity can be delivered even at 1C at 30 °C. Moreover, the capacity retentions are higher than 75% after 200 cycles at different current rates, and the battery showed smaller capacity fading after cycling at 50 °C. Furthermore, the practical possibility of the battery concept and fabrication method were confirmed by a laminated prototype flexible battery.
ACS Applied Materials & Interfaces 12 (33), 37067-37078
Submitted: April 27, 2020
Accepted: July 20, 2020
Published: July 20, 2020