New Class of Ni‐Rich Cathode Materials Li[NixCoyB1−x−y]O2 for Next Lithium Batteries. Issue 25 (14th May 2020)

• Record Type: Journal Article
• Authors: Ryu, Hoon‐Hee; Park, Nam‐Yung; Yoon, Dae Ro; Kim, Un‐Hyuck; Yoon, Chong S.; Sun, Yang‐Kook
• Is Part Of: Advanced energy materials. Volume 10:Issue 25(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-05-14
• Subjects: boron doping -- microcrack suppression -- microstructure -- Ni‐rich layered cathodes; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202000495
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: A new class of layered cathodes, Li[Ni x Co y B1− x − y ]O2 (NCB), is synthesized. The proposed NCB cathodes have a unique microstructure in which elongated primary particles are tightly packed into spherical secondary particles. The cathodes also exhibit a strong crystallographic texture in which the a – b layer planes are aligned along the radial direction, facilitating Li migration. The microstructure, which effectively suppresses the formation of microcracks, improves the cycling stability of the NCB cathodes. The NCB cathode with 1.5 mol% B delivers a discharge capacity of 234 mAh g −1 at 0.1 C and retains 91.2% of its initial capacity after 100 cycles (compared to values of 229 mAh g −1 at 0.1 C and 78.8% for pristine Li[Ni0.9 Co0.1 ]O2 ). This study shows the importance of controlling the microstructure to obtain the required cycling stability, especially for Ni‐rich layered cathodes, where the main cause of capacity fading is related to mechanical strain in their charged state. Abstract : A new class of layered cathodes, Li[Ni x Co y B1− x − y ]O2 (NCB), is proposed. NCB cathodes have a highly oriented microstructure in which the primary particle widths can be controlled by varying the boron fraction in the composition. The unique microstructural configuration of the NCB cathodes effectively suppress the formation of microcracks and significantly improve the cycling stability compared to a conventional cathode.