Lithium cycling efficiency and conductivity for high dielectric solvent/low viscosity solvent mixed systems
✍ Scribed by Shin-ichi Tobishima; Takeshi Okada
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- English
- Weight
- 537 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0013-4686
No coin nor oath required. For personal study only.
✦ Synopsis
Lithium cycling efficiency on a lithium substrate (Li-on-Li cycling) and conductivity for various mixed solvent systems of high dielectric solvent (HDS) and low viscosity solvent (LVS) were examined for secondary lithium batteries. For the HDS, sulfolane, dimethylsulfoxide, y-lactones, propylene carbonate (PC) and ethylene carbonate (EC) were used. For the LVS, tetrahydrofuran (THF), 2-methyl-THF, 1,2dialkoxyethanes and 1,3-dinxalane (DOL) were used . For the solute, LiAsF9 , LiBF" LiCF,CO ] and LiCIO, were used . Lithium cycling efficiencies newly measured on a Li substrate (E") for ECJLVS or PCjLVS were ca 5 % or 15 % higher than those previously obtained by simple cycling of Li on a Pt substrate, while the order of Li cycling efficiencies to LVS change is sllnilar in both cases, except for EC ; DOL or PC/DOL . The reasons seem to be that the Li-on-Li cycling minimizes the influence of electrochemical Li/Pt alloying and partial solvent oxidation during the cycle on Li cycling efficiency . The E . values in HDS/LVS mixed systems incorporating LiAsF" or LiCIO 4 tended to increase with adecrease in the reactivity to Li, of not only LVS but also HDS. ECTHF systems incorporating LiAsF 9 or LiCIO, showed high E, values ofca 95 % even by Lion-Li cycling, the valueheing higher than those (ca92%)l'or LiBFI or LiCF 3 SO 5 systems. In addition,,for all the HDS/LVS mixed systems examined in this work, conductivities were higher than those for HDS or LVS single solvent systems . In regard to both conductivity and Li cycling efficiency, HDS/LVS mixed systems are considered to be effective in various lithium battery applications .