本研究以水熱法合成不同形貌之磷酸鋰錳奈米粒子，並成功以鈷離子與鎂離子取代錳離子改變電化學性質，亦以X-射線繞射分析(XRD)與掃描式電子顯微鏡(SEM)進行特性分析，以循環伏安法和循環壽命測試電化學性質。反應物濃度與界面活性劑濃度皆會影響粒子大小與形狀，最窄之針狀粒子寬度約為15 nm。在充放電速率為0.1 C下，未摻雜之磷酸鋰錳比電容量最佳可達73.8 mAh/g，10%鈷離子摻雜情況提升比電容量至121.1 mAh/g，五十圈穩定度為42.1%。欲提升穩定度，進一步以鈷離子與鎂離子共摻雜，15%鈷和5%鎂取代可將五十圈之穩定度提升至81.7%，比電容量為110.9 mAh/g。

In this research, lithium manganese phosphate nanoparticles of different morphologies were synthesized by solvothermal processes. Effects of manganese ions substituted by cobalt ions and magnesium ions were also investigated. The structure and morphology information were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The electrochemical properties of these materials were analyzed using cyclic voltammetry and cycling life test.
The particle size and shape were affected by concentration of both reactants and surfactants. The needle-like shape particles were the narrowest ones, approximately 15 nm in width.
At the charging and discharging rate of 0.1 C, non-doped lithium manganese phosphate nanoparticles had a discharge capacity of 73.8 mAh/g, while doped with 10% cobalt ions, the discharge capacity was improved to 121.1 mAh/g, and the capacity retention after 50 cycles was 42.1%.
The effects of LiMnPO4 co-doped with Co2+ and Mg2+ were also investigated. The sample with 15% cobalt ions and 5% magnesium ions had the largest improvement in retention of 81.7% after 50 cycles, and the discharge capacity was 110.9 mAh/g.

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