Advanced Concentration Gradient Cathode Material with Two‐Slope for High‐Energy and Safe Lithium Batteries

Li[Ni0.65Co0.13Mn0.22]O2 cathode with two-sloped full concentration gradient (TSFCG), maximizing the Ni content in the inner part of the particle and the Mn content near the particle surface, is synthesized via a specially designed batch-type reactor. The cathode delivers a discharge capacity of 200 mAh g−1 (4.3 V cutoff) with excellent capacity retention of 88% after 1500 cycles in a full-cell configuration. Overall electrochemical performance of the TSFCG cathode is benchmarked against conventional cathode (CC) with same composition and commercially available Li[Ni0.8Co0.15Al0.05]O2 (NCA). The TSFCG cathode exhibits the best cycling stability, rate capability, and thermal stability of the three electrodes. Transmission electron microscopy analysis of the cycled TSFCG, CC, and NCA cathodes shows that the TSFCG electrode maintains both its mechanical and structural integrity whereas the NCA electrode nearly pulverizes due to the strain during cycling.

[1]  Chong Seung Yoon,et al.  Nanostructured high-energy cathode materials for advanced lithium batteries. , 2012, Nature materials.

[2]  Yang-Kook Sun,et al.  Synthesis and characterization of Li[(Ni0.8Co0.1Mn0.1)0.8(Ni0.5Mn0.5)0.2]O2 with the microscale core-shell structure as the positive electrode material for lithium batteries. , 2005, Journal of the American Chemical Society.

[3]  Yang‐Kook Sun,et al.  Synthetic optimization of Li[Ni 1/3Co 1/3Mn 1/3]O 2 via co-precipitation , 2004 .

[4]  Xiao‐Qing Yang,et al.  INVESTIGATION OF THE LOCAL STRUCTURE OF THE LINI0.5MN0.5O2 CATHODE MATERIAL DURING ELECTROCHEMICAL CYCLING BY X-RAY ABSORPTION AND NMR SPECTROSCOPY , 2002 .

[5]  Yangang Sun,et al.  Comparison of nanorod-structured Li[Ni0.54 Co0.16 Mn0.30 ]O2 with conventional cathode materials for Li-ion batteries. , 2014, ChemSusChem.

[6]  Chester G. Motloch,et al.  Power fade and capacity fade resulting from cycle-life testing of Advanced Technology Development Program lithium-ion batteries , 2003 .

[7]  Chong Seung Yoon,et al.  Improvement of long-term cycling performance of Li[Ni0.8Co0.15Al0.05]O2 by AlF3 coating , 2013 .

[8]  Hajime Arai,et al.  Electrochemical and thermal behavior of LiNi1-zMzO2 (M = Co, Mn, Ti) , 1997 .

[9]  G. L. Henriksen,et al.  Aluminum-doped lithium nickel cobalt oxide electrodes for high-power lithium-ion batteries , 2004 .

[10]  Ilias Belharouak,et al.  High-energy cathode material for long-life and safe lithium batteries. , 2009, Nature materials.

[11]  Robert Kostecki,et al.  Local-probe studies of degradation of composite LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} cathodes in high-power lithium-ion cells , 2004 .

[12]  Daniel P. Abraham,et al.  Surface changes on LiNi0.8Co0.2O2 particles during testing of high-power lithium-ion cells , 2002 .

[13]  Y. Meng,et al.  Cation Ordering in Layered O3 Li[NixLi1/3-2x/3Mn2/3-x/3]O2 (0 ≤ x ≤ 1/2) Compounds , 2005 .

[14]  Chong Seung Yoon,et al.  Cathode Material with Nanorod Structure—An Application for Advanced High-Energy and Safe Lithium Batteries , 2013 .

[15]  Ilias Belharouak,et al.  Safety characteristics of Li(Ni0.8Co0.15Al0.05)O2 and Li(Ni1/3Co1/3Mn1/3)O2 , 2006 .

[16]  J. Shim,et al.  Electrochemical analysis for cycle performance and capacity fading of a lithium-ion battery cycled at elevated temperature , 2002 .

[17]  Y. Ukyo,et al.  Performance of LiNiCoO2 materials for advanced lithium-ion batteries , 2005 .

[18]  Yang‐Kook Sun,et al.  Improvement of cycling performance of Li1.1Mn1.9O4 at 60 °C by NiO addition for Li-ion secondary batteries , 2006 .

[19]  J. Dahn,et al.  Thermal stability of LixCoO2, LixNiO2 and λ-MnO2 and consequences for the safety of Li-ion cells , 1994 .