Li-Mn-Al-O锂离子正极材料的合成及其性能

来源期刊：中南大学学报(自然科学版)2006年第5期

论文作者：李义兵 陈白珍 胡拥军 李改变 陈亚 金基明

文章页码：913 - 918

关键词：掺铝;单斜; Li₂MnO₃;复相;电化学性能

Key words：doping Al; monoclinic; Li₂MnO₃; complex phase; electrochemical performance

摘    要：以Mn₂O₃, Al(NO₃)₃·9H₂O和LiOH·H₂O为原料,采用固相合成法制备掺铝锰酸锂材料。研究结果表明:掺铝样品是一种复相,物相组成为尖晶石LiMn₂O₄和单斜型Li₂MnO₃;掺铝后材料颗粒粒度变小,晶体形状为类球形;该材料性能介于层状LiMnO₂和尖晶石LiMn₂O₄性能之间,当掺铝量为0.1时,最高容量可达197mA·h·g^-1,循环20次后,容量还高于在190 mA·h·g^-1;掺铝可提高材料的电导率,促进锂离子在电极中的迁移,提高材料电化学性能。

Abstract: Doping Al lithium manganese oxides were prepared using Mn₂O₃, Al(NO₃)₃·9H₂O and LiOH·H₂O as raw materials by solid-state method. The results show that the phase of Aldoped samples is a complex phase, such as spinel LiMn₂O₄ and monoclinic Li₂MnO₃. The grain sizes of doping Al sample become small and its crystal shape is a quasi-sphere compared with layered LiMnO₂, respectively. The highest discharge capacity is 197 mA·h·g^-1and can retain above 190 mA·h·g^-1at the 20th cycle when doping Al amount is 0.1. Doping Al can increase material conductance, then accelerate transfer of Li-ion in the electrodes, and improve the electrochemical performance of materials.