Gast ::
| Hauptseite > Publikationsdatenbank > Development of nanomaterials for all-solid-state lithium ion batteries |
| Hauptseite > Publikationsdatenbank > Development of nanomaterials for all-solid-state lithium ion batteries |
| Conference Presentation (Invited) | FZJ-2015-00370 |
; ; ; ; ; ; ; ;
2014
Abstract: In conventional lithium ion batteries liquid electrolytes are used for the ionic transport. The organic solvents required cause safety issues as flammability and leakage. In order to avoid these hazards, the liquid electrolyte is replaced by solid electrolytes. Lithium ion conducting sulfides [1], oxides [2], and phosphates [3] are developed for the construction of all-solid-state Li-ion batteries. A promising oxide material with desirable properties is the garnet-structured Li7La3Zr2O12 (LLZ). Its ionic conductivity (about 10-4 S/cm) and thermal stability (up to 1250°C) are reasonably high. This material has a very large electrochemical window being stable up to 8 V vs. Li/Li+ making it feasible for desired high voltage cathode materials. Partial aliovalent substitution of Li by Al or Zr by Ta lowers the required crystallization temperature of the conductive cubic phase. However, compared to conventional liquid electrolytes, LLZ exhibits an about one order of magnitude higher ionic resistivity. Therefore, to maintain low overall resistances of the cells, thin film electrolytes are desirable to compensate the lower conductivity. The thin film deposition of cubic garnet structured LLZ has posed troubles on non-single crystalline substrates [4,5] so far. We successfully obtained cubic LLZ films by r.f. magnetron sputtering and dip coating on metal foil substrates and cathode material. These films were analyzed by X-ray diffraction, scanning electron microscopy (SEM), secondary ion mass spectrometry (SIMS), and electrochemical tests. Thin electrolyte films were compared to reference bulk materials obtained from solid-state reaction powder synthesis, compaction and sintering..[1] Kamaya et al., Nature Materials 10 (2011) 682[2] Murugan et al., Angew. Chem. Int. Ed. 46(2007) 7778[3] Propovici et al., J. Am. Ceram. Soc. 94 (2011) 3847[4] Kalita et al., Solid State Ionics 2012 (229) 14[5] Chen et al. J., Mater. Chem. A. 2014 Accepted Manuscript
|
The record appears in these collections: |