Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6603262 | Electrochimica Acta | 2018 | 8 Pages |
Abstract
The sol-freeze-drying method is successfully applied to tune the structure of Co-free Li-rich Mn-based layered material (Li1.2Mn0.6Ni0.2O2). The structure, morphology and electrochemical performances of the tuned materials are compared with its counterpart prepared by traditional sol-gel method. The results confirm that sol-freeze-drying method is an effective approach to homogenize the transition metal distribution in Li1.2Mn0.6Ni0.2O2 without surface segregation of Ni. The specific capacity of Li1.2Mn0.6Ni0.2O2 synthesized by sol-free-drying method is 232â¯mAh gâ1 after 100 cycles at 0.2C with 96% of initial discharge capacity retained. It is much higher than the 182â¯mAh gâ1 of Li1.2Mn0.6Ni0.2O2 prepared by sol-gel method with poor capacity retention of 79%. Li1.2Mn0.6Ni0.2O2 synthesized by sol-free-drying method delivers the capacities of 252, 220, 192, 148, and 84â¯mAh gâ1 at rates of 0.1C, 0.5C, 1C, 2C, and 5C, respectively. Besides, impedance spectroscopy shows that the charge-transfer resistance of Li1.2Mn0.6Ni0.2O2 synthesized by sol-free-drying method after 20 cycles increases from 43â¯Î© to 51â¯Î©, which is much lower than that of Li1.2Mn0.6Ni0.2O2 prepared by sol-gel method from 42â¯Î© to 78â¯Î©.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
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Authors
Puheng Yang, Honglei Li, Xin Wei, Shichao Zhang, Yalan Xing,