A well-controlled cracks and gliding-free single-crystal Ni-rich cathode for long-cycle-life lithium-ion batteries

• Published in: Journal of alloys and compounds 2022-11, Vol.924, p.166375, Article 166375
• Main Authors: Saleem, Adil, Hussain, Arshad, Ashfaq, M. Zeeshan, Javed, Muhammad Sufyan, Rauf, Sajid, Hussain, M. Muzammal, Saad, Ali, Shen, Jun, Majeed, Muhammad K., Iqbal, Rashid
• Format: Article
• Language: English
• Subjects: Additives; Cathodes; Commercialization; Controlled cracks; Cracks; Cycles; Density functional theory; Electrode materials; Gliding; Grain size; Ion diffusion; Lattice gliding/micro-cracks; Lithium; Lithium-ion batteries; Microcracks; Production methods; Rechargeable batteries; Reliability engineering; Single crystal cathode; Single crystals; Structural reliability; Structural stability
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.166375

Single-crystalline (SC) high energy nickel (Ni)-rich cathodes play a key role as a potential cathode material in lithium-ion batteries (LIBs) to address the challenges in a hierarchical structure of their secondary particles by decreasing phase boundaries and materials surfaces. The SC LiNi0.78Mn0.12Co0.1O2 (SC-NMC78) cathode with primary particles of several micron-sized particles are developed and thoroughly investigated in this study, demonstrating superior cycling performance, along with significantly enhanced structural reliability after long-term cycling. The improved SC-NMC78 has an octahedral SC morphology with a modest grain size, which reduces the lithium-ion diffusion route and enhances structural stability. The SC-NMC78 offers a high discharge capacity of 175 and 155 mAh g−1 at 0.2 and 1 C, respectively, and better capacity retention of 132 mAh g−1 after 200 cycles at 1 C as a cathode in LIBs. The cycled SC-NMC78 particles exhibited no lattice gliding and micro-cracks, demonstrating that the SC shape may substantially reduce anisotropic micro-strain. This efficient, repeatable, and customizable method for producing SC Ni-rich cathodes without any additives should accelerate their commercialization. The density functional theory also proved that the low global hardness of Ni2+ in SC-NMC78 and optimized content of Ni/Li exchange were well-consistent with the experimental findings. [Display omitted] •The SC-NMC78 with 1–3 µm diameter is developed and systematically investigated for the first time.•SC-NMC78 effectively mitigates undesired side interactions and significantly prevents lattice gliding and micro-cracks.•The as-obtained cathode shows excellent capacity retention and thermal stability.•The intrinsic advantages of single-crystalline architecture are clearly unraveled.