Suppressing side reactions at the cathode-electrolyte interface (CEI) is critical for alleviating capacity fading of the high-voltage (>5 V) spinel cathode material LiNi0.5Mn1.5O4 (LNMO). The primary bottleneck in conventional nanoengineering of LNMO involves an antagonistic relationship between the positive effects of the nanometer particle size and negative effects stemming from the larger CEI area. Inspired by Buckminster Fuller's geodesic domes, we have designed a seamless LNMO hollow sphere (S-LNMO) that comprises average 120 nm-sized triangles and truncated triangle subunits by means of grain growth orientation. The “tensegrity” structure has efficiently hindered the interfacial side reaction, which occurs only within a depth of 5 nm from the surface, thereby improving its electrochemical stability. The embedded layered Li2TiO3 (LTO) in bulk S-LNMO (LTO:S-LNMO) region further improved the high-rate performance, demonstrating an ∼110 mAh/g capacity with 80.9% retention after 400 cycles at 5 C and remaining stable after 900 cycles at 5 C even after being stored at 50 °C for one week.
Bibliographical noteFunding Information:
This work was supported by the NRF of Korea Grant funded by the Ministry of Science, ICT & Future Planning ( 2014M3A7B4051747 , NRF-2015M2A2A6A01045277 ). This work was supported (in part) by the Yonsei University Future-leading Research Initiative of 2015 ( 2015-22-0067 ). This work was supported by the Energy Efficiency & Resources Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) , granted financial resource from the Ministry of Trade, Industry & Energy , Republic of Korea ( 20152010103470 ).
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering