Understanding Electrochemical Performance Enhancement with Quaternary NCMA Cathode Materials
Shengde Dong1,2, Fang Liu1, Yue Leng1,2
1College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 20, 2023
Summary
Aluminum-doped nickel-rich cathode materials (NCMA) show improved mechanical strength and electrochemical performance in lithium-ion batteries compared to standard nickel-rich cathode materials (NCM). This enhancement reduces structural damage from microcracks, boosting battery longevity.
Area of Science:
- Materials Science
- Electrochemistry
- Solid-state Chemistry
Background:
- Nickel-rich cathode materials are crucial for high-performance lithium-ion batteries.
- Microcrack-induced structural damage limits the practical application of these materials.
- Developing strategies to enhance mechanical stability is essential for improving battery cycle life.
Purpose of the Study:
- To synthesize and evaluate aluminum-doped nickel-rich cathode materials (NCMA) for lithium-ion batteries.
- To investigate the effect of aluminum doping on the structural integrity and electrochemical performance of Ni-rich cathodes.
- To understand the mechanism by which aluminum doping mitigates microcrack formation.
Main Methods:
- Synthesis of LiNi0.8Co0.1Mn0.1O2 (NCM) and Li(Ni0.8Co0.1Mn0.1)0.98Al0.02O2 (NCMA) via high-temperature solid-phase method.
- Electrochemical testing to assess discharge capacity and cycle retention.
- Atomic force microscopy (AFM) to measure mechanical properties (DMT modulus).
- Density functional theory (DFT) calculations to analyze structural changes and bonding.
Main Results:
- NCMA demonstrated superior electrochemical performance with a discharge capacity of 141.6 mAh g-1 and 74.92% cycle retention after 300 cycles at 1 C, compared to NCM (109.7 mAh g-1, 61.22% retention).
- Atomic force microscopy revealed a higher Derjaguin-Muller-Toporov (DMT) modulus for NCMA, indicating enhanced mechanical strength.
- DFT calculations confirmed that aluminum doping stabilizes the NCMA structure by mitigating anisotropic lattice changes during delithiation, attributed to stronger Al-O bonds.
Conclusions:
- Aluminum doping significantly enhances the mechanical stability and electrochemical performance of Ni-rich cathode materials.
- The improved structural integrity and reduced microcrack formation in NCMA contribute to superior cycle life in lithium-ion batteries.
- This study highlights aluminum doping as an effective strategy for developing robust and long-lasting Ni-rich cathodes.
