Improved electrochemical performance and capacity fading mechanism of nano-sized LiMn0.9Fe0.1PO4 cathode modified by polyacene coating
Improved electrochemical performance and capacity fading mechanism of nano-sized LiMn0.9Fe0.1PO4 cathode modified by polyacene coating
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DOI：
10.1039/c4ta05900j
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发表时间：
2015
影响因子：
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通讯作者：
Liguang Wang;Pengjian Zuo;Geping Yin;Yulin Ma;Xinqun Cheng;C. Du;Yunzhi Gao
中科院分区：
文献类型：
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作者：
Liguang Wang;Pengjian Zuo;Geping Yin;Yulin Ma;Xinqun Cheng;C. Du;Yunzhi Gao
采用溶剂热法在水和乙醇的混合溶剂中制备了LiMn 1 − xFexPO 4（x = 0和0.1）纳米材料。LiMn0.9Fe0.1PO4-聚并苯（PAS）复合材料表现出高电导率（0.15 S cm−1），导致优异的倍率性能和良好的循环寿命。LiMn0.9Fe0.1PO4-PAS复合材料在0.1 C、1 C和10 C下的放电容量分别为161、141和107 mA h g−1。LiMn0.9Fe0.1PO4纳米片周围均匀分布的导电聚并苯增强了纳米尺寸的晶体颗粒的电子接触，并抑制了循环过程中与结构演变相关的锰溶解。具体而言，锰的溶解、电解质的分解和反位缺陷是影响橄榄石型铁掺杂磷酸锰锂正极材料容量退化的最重要因素。
Nano-sized LiMn1−xFexPO4 (x = 0 and 0.1) was prepared by a solvothermal method in a mixed solvent of water and ethanol. LiMn0.9Fe0.1PO4–polyacene (PAS) composite exhibits a high conductivity (0.15 S cm−1), resulting in an excellent rate performance and good cycle life. The LiMn0.9Fe0.1PO4–PAS composite delivers a discharge capacity of 161, 141, and 107 mA h g−1 at 0.1 C, 1 C and 10 C, respectively. The well-distributed conductive polyacene surrounding the LiMn0.9Fe0.1PO4 nanoplates enhances the electronic contact of the nanosized crystalline particles and suppresses the manganese dissolution related to the structure evolution during cycling. Specifically, the manganese dissolution, electrolyte decomposition and the antisite defects are the most significant factors that impact the capacity degradation of olivine iron-doped lithium manganese phosphate cathode materials.