Journal of Power Sources, Vol.292, 31-38, 2015
Electrochemical and safety performance of Li pre-doping free cell using tin-phosphate glass-silicon composite anode
The Li pre-doping free cells using tin-phosphate glass (GSPO)-silicon composite anodes and lithium-rich layered oxide (LR-NMC) cathode were developed, in which the irreversible capacity of the cathode was utilized in order to compensate that of the anode. The irreversible capacity was equalized to that of the cathode at a Si/(GSPO + Si) mass ratio, r, of 0.8. The cell using the composite anode of r = 0.8 displayed a discharge capacity of 187 mAh g(-1) as the cathode capacity at 30 degrees C and the 0.1C-rate. The long cycle performance of over 100 charge discharge cycles was achieved. The cells also showed an excellent high- and low-temperature performance and a good rate performance. A stable performance was observed for over 50 cycles at 60 degrees C and the 0.5C-rate, and a high capacity of ca. 100 mAh g(-1) as the cathode capacity even at -20 degrees C and the 0.2C-rate. The cell could discharge even at the 10C-rate. Furthermore, the Li pre-doping free cell showed an outstanding safety performance during the nail penetration test. When the 1500 mAh cell using the composite anode was penetrated by a nail, no thermal runaway was observed during the test. (C) 2015 Elsevier B.V. All rights reserved.
Keywords:Li-ion battery;High energy density;Irreversible capacity;Tin-phosphate glass anode material;Si anode material;Nail penetration test