Paper form copper ion conductive solid electrolyte

A paper form solid electrolyte (PFSE) with good conductivity and flexibility was developed. PFSE is made of an inorganic–organic composite consisting of a copper ion conductive solid electrolyte of Rb 4 Cu 16 I 7 Cl 13 (SE) and a polymer binder embedded in a synthetic fibre network. A PFSE with styrene–butadiene based synthetic rubber (SB) was found to give the highest conductivity among the binding materials that we examined. The SB content was changed from 10 vol% to 90 vol% in the PFSE, and the electrical properties and the damp resistance of PFSE were evaluated. Electrical conductivity decreased slightly with an SB content below 70 vol% and abruptly above 70 vol%. The damp resistance of PFSE improved with the increase of the SB content and was superior to that of the raw powder. The PFSE with 65 vol% SB showed relatively high conductivity, 3 × 10 −3 S/cm, which was sufficient for battery use, and good damp resistance.