| 초록 |
The commercialized lithium ion battery has ignition and explosion. To solve this problem, all solid state battery has been researched since 1970’s. But the conductivity has not reached 1×10-4 S/cm, and furthermore poor mechanical strength hinders the application as free standing film. In order to develop better SPE, we tried new lithium salt which is lithium trifluoroborane phytate (LiTFBP). It showed fairly high conductivity (3.14×10-5 S/cm) similar to that of LiTFSI at RT, but had excellent mechanical strength as free standing film at RT. LiTFBP is a multi-ionic lithium salts with 12 lithium ions, whose interaction with PEO may result in increased mechanical strength. The mechanical properties were strain of 187% and tensile strength of 1.3 MPa. Moreover, LiTFBP with –BF3 end groups easily dissociated lithium ions, and the large anions could allow the lithium ion to conduct as a single ion conductor. These results showed both high conductivity and mechanical strength. |
