Complementary dual-doping of LiNi0.8Co0.1Mn0.1O2 cathode enhances ion-diffusion and stability for Li-ion batteries

• Published in: Chinese chemical letters 2023-06, Vol.34 (6), p.107718-582, Article 107718
• Main Authors: Wang, Zhihong, Zhu, Huawei, Yu, Haifeng, Zhang, Tao, Hu, Yanjie, Jiang, Hao, Li, Chunzhong
• Format: Article
• Language: English
• Subjects: Cycling stability; Dual-doping; High power; Li-ion batteries; LiNi0.8Co0.1Mn0.1O2
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2022.07.061

The Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) layered cathodes endow Li-ion batteries (LIBs) with high energy density. However, they usually suffer from limited ion-diffusion and structural instability during cycling. Although doping strategy can effectively alleviate these issues, the coupling effects of multi-element doping and the corresponding performance enhancement mechanism have been yet unclear. Here, we report a Zr/Ti dual-doped NCM811 cathode material (ZT-NCM811), in which Zr-ion is doped into both transition metal (TM) layers and lithium layers and Ti-ion is only distributed in TM layers. The dual-doping can effectively enhance crystal structure stability via inhibiting the lattice collapse along c-axis and decreasing the Li/Ni disorder. Meantime, the lattice oxygen escape is also greatly reduced due to the presence of stronger Zr-O and Ti-O bonds, further mitigating the crystal surface parasitic reactions with electrolyte. The resultant ZT-NCM811 exhibits high specific capacity of 124 mAh/g at even 10 C, much higher than undoped and single-doped NCM811, and a retention of 98.8% at 1 C after 100 cycles. The assembled ZT-NCM811/graphite full cell also delivers superior battery performances and durability. Graphical Abstract. [Display omitted] .