Assessing Long-Term Cycling Stability of Single-Crystal Versus Polycrystalline Nickel-Rich NCM in Pouch Cells with 6 mAh cm-2 Electrodes
- Swiss Federal Laboratories for Materials Science and Technology (Empa), Dübendorf (Switzerland)
- Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
- Paul Scherrer Inst. (PSI), Villigen (Switzerland)
- Central South University, Changsha (China)
- Yanshan University, Qinhuangdao (China)
Lithium-ion batteries based on single-crystal LiNi1-x-yCoxMnyO2 (NCM, 1-x-y ≥ 0.6) cathode materials are gaining increasing attention due to their improved structural stability resulting in superior cycle life compared to batteries based on polycrystalline NCM. However, an in-depth understanding of the less pronounced degradation mechanism of single-crystal NCM is still lacking. Here, a detailed postmortem study is presented, comparing pouch cells with single-crystal versus polycrystalline LiNi0.60Co0.20Mn0.20O2 (NCM622) cathodes after 1375 dis-/charge cycles against graphite anodes. The thickness of the cation-disordered layer forming in the near-surface region of the cathode particles does not differ significantly between single-crystal and polycrystalline particles, while cracking is pronounced for polycrystalline particles, but practically absent for single-crystal particles. Transition metal dissolution as quantified by time-of-flight mass spectrometry on the surface of the cycled graphite anode is much reduced for single-crystal NCM622. Similarly, CO2 gas evolution during the first two cycles as quantified by electrochemical mass spectrometry is much reduced for single-crystal NCM622. Benefitting from these advantages, graphite/single-crystal NMC622 pouch cells are demonstrated with a cathode areal capacity of 6 mAh cm-2 with an excellent capacity retention of 83% after 3000 cycles to 4.2 V, emphasizing the potential of single-crystalline NCM622 as cathode material for next-generation lithium-ion batteries.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- National Natural Science Foundation of China (NSFC); Swiss Competence Center for Energy Research (SCCER); USDOE Office of Science (SC), Biological and Environmental Research (BER)
- Grant/Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1987547
- Report Number(s):
- PNNL-SA-169057
- Journal Information:
- Small, Journal Name: Small Journal Issue: 14 Vol. 18; ISSN 1613-6810
- Publisher:
- WileyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Long-Term Cyclability of NCM-811 at High Voltages in Lithium-Ion Batteries: an In-Depth Diagnostic Study
A universal etching method for synthesizing high-performance single crystal cathode materials
Design and Demonstration of Three-Electrode Pouch Cells for Lithium-Ion Batteries
Journal Article
·
Wed Aug 26 20:00:00 EDT 2020
· Chemistry of Materials
·
OSTI ID:2217338
A universal etching method for synthesizing high-performance single crystal cathode materials
Journal Article
·
Mon May 24 20:00:00 EDT 2021
· Nano Energy
·
OSTI ID:1787558
Design and Demonstration of Three-Electrode Pouch Cells for Lithium-Ion Batteries
Journal Article
·
Tue Jun 13 20:00:00 EDT 2017
· Journal of the Electrochemical Society
·
OSTI ID:1376322