| 引用本文: | 曾莹莹,郭秀艳,陈海辉,马国金.锰酸锂表面掺杂TiO2的工艺及性能测试[J].材料科学与工艺,2019,27(2):84-89.DOI:10.11951/j.issn.1005-0299.20170167. |
| ZENG Yingying,GUO Xiuyan,CHEN Haihui,MA Guojin.Preparation and performance test of surface-TiO2-doped lithium manganate[J].Materials Science and Technology,2019,27(2):84-89.DOI:10.11951/j.issn.1005-0299.20170167. |
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| 摘要: |
| 尖晶石锰酸锂电池容量衰减是限制其大规模应用的瓶颈问题，抑制锰溶解是减少其容量衰减的重要措施之一.本文以MnCO3和Li2CO3为原料，采用球磨结合高温固化的方法制备了尖晶石LiMn2O4原材料，采用溶胶-凝胶法实现对尖晶石锰酸锂进行表面包覆二氧化钛.将包覆后材料经过高温长时间煅烧，使得金属钛离子能扩散到锰酸锂颗粒材料表层中，形成LiTixMn2-xO4尖晶石结构薄层.通过对锰酸锂在高温电解液中的溶解对比性试验，给出掺杂薄层作用的直接证据，并对全电池高温环境下电化学循环性能进行了对比测试.结果表明，锰酸锂颗粒表面涂覆TiO2后，经过750 ℃煅烧6 h，实现了在尖晶石LiMn2O4表面形成了LiMn2-xTixO4掺杂薄层，其形态、结构均与LiMn2O4类似.表面掺杂TiO2工艺能够显著抑制LiMn2O4高温环境下的锰离子溶解，提高锰酸锂电池的使用寿命和高温性能. |
| 关键词: 尖晶石锰酸锂 容量衰减 锰离子溶解 二氧化钛掺杂表层 高温性能 |
| DOI：10.11951/j.issn.1005-0299.20170167 |
| 分类号:TM911.4 |
| 文献标识码:A |
| 基金项目:国家自然科学基金资助项目(6,5)；江西省科技厅科技计划项目(20161BBE50052)；江西省教育厅科技计划项目(GJJ150775). |
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| Preparation and performance test of surface-TiO2-doped lithium manganate |
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ZENG Yingying1, GUO Xiuyan1, CHEN Haihui2, MA Guojin3
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(1.School of Mechanical & Electrical Engineering, Jinggangshan University, Ji′an 343009, China; 2.School of Chemistry & Chemical Engineering, Jinggangshan University, Ji′an 343009, China; 3.School of Building Engineering, Jinggangshan University, Ji′an 343009, China)
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| Abstract: |
| Capacity fading of spinel lithium manganate-based batteries is a bottleneck that constrains their large-scale application, so restraining the dissolution of Mn has become a key measurement to reduce capacity fading. In this study, the spinel LiMn2O4 material was prepared by the procedures of wet grinding and high temperature solidification using MnCO3 and Li2CO3 as raw materials. The surface of the spinel LiMn2O4 was coated with TiO2 using sol-gel method, and the modified material was calcinated at high temperature for a long time, so that the metal titanium ions could diffuse into the surface layer of the spinel LiMn2O4, forming a layer of LiTixMn2-xO4. The experiment at elevated temperature provided direct evidence for the effects of modification and calcination, and the electrochemical cycle performances of the whole cell with doped LiMn2O4 or pristine LiMn2O4 cathodes at high temperature were tested and compared. Results show that after the LiMn2O4 was coated by TiO2 on the surface and calcined at 750 ℃ for 6 h, the LiMn2-xTixO4 thin layer on the surface of spinel LiMn2O4 was successfully realized, whose morphology and structure were similar to those of LiMn2O4, which greatly reduced phase segregation or separation. The surface doped TiO2 process can significantly suppress the dissolution of manganese ions from LiMn2O4 cathode in high temperature environment, as well as improve the service life and elevated temperature performance of lithium manganese oxide batteries. |
| Key words: spinel lithium manganate capacity fade manganese ion dissolution TiO2-Doped surface layer elevated temperature performance |
