Optimization of dielectric heating parameters in the production of high‐voltage LiNiPO4‐core and carbon‐shell ceramics

• Published in: Journal of the American Ceramic Society Vol. 100; no. 12; pp. 5668 - 5680
• Main Author: Ornek, Ahmet
• Format: Journal Article
• Language: English
• Published: Columbus Wiley Subscription Services, Inc 01.12.2017
• Subjects: cathode material; Cathodes; Chemical synthesis; Electric potential; Electrochemical analysis; electrochemical characterization; Electron microscopy; lithium nickel phosphate; Li‐ion batteries; microwave & solvothermal synthesis; Morphology; Shells; Stability analysis
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/jace.15111

Excellent core‐shell morphology and nanoscale high‐voltage LiNiPO4@C cathode materials have been synthesized by a low‐level and long‐time microwave and solvothermal synthesis methodology. The effects of the changing physicochemical parameters on the crystal‐quality and electrochemical properties of the products have been evaluated in relation to the cycling stability. X‐ray diffraction analysis shows that it is possible to synthesize phase‐pure LiNiPO4 material when the reaction parameters are carefully elaborated. High‐resolution transmission electron microscopy analysis reveals a core‐shell morphology with a coating thickness of 6‐8 nm for 30 minutes at 180°C solvothermal temperature and time‐spread microwave energy. This mentioned cathode material exhibits the best electrochemical properties, achieving a discharge capacity of 157 mAh·g−1 at a 0.l C current rate, and shows a remarkable 81% capacity retention at the end of the 80th cycle.