本實驗將使用溶膠凝膠法(Sol-gel Process)進行高熵氧化物　(Co0.2Cu0.2Mg0.2Ni0.2Zn0. 2O)粉體之製備，並進一步作為鋰離子電池之負極材料進行研究。此製程技術常使用於合成陶瓷粉末，該技術具有粒徑均勻等優點，能有利於電極材料之應用。本研究將利用溶膠凝膠法製備之高熵氧化物(Co0.2Cu0.2Mg0.2Ni0.2Zn0.2O)進行鋰離子電池負極材料之應用，並探討高熵氧化物的電化學性能表現與各金屬陽離子與材料之關聯性，透過簡單地改變元素組成來進行電化學性質之測試。
在鋰離子電池實作成果方面，本研究開發之高熵氧化物負極材料，經鋰離子半電池之測試，在50mAh g-1之電流下，其電容值將可達到600 mAh g-1。此外，透過改變高熵氧化物之組成陽離子可進一步證實熵穩定作用對於電池容量而言能帶來顯著之好處，並大幅提高了循環穩定性。另外也進一步結合LNMO之高電壓正極進行全電池之測試，證明高熵氧化物未來將具備替代現今鋰離子電池電極材料之潛力。

In this study, sol-gel method will be used to prepare high entropy oxide (Co0.2Cu0.2Mg0.2Ni0.2Zn0.2O) powder, and will be further studied as an anode material for lithium-ion batteries. Sol-gel method is often used to synthesize powders. This fabrication process not only has the advantages of uniform particle size, but also suitable for the application of electrode materials. This study uses the high entropy oxide (Co0.2Cu0.2Mg0.2Ni0.2Zn0.2O) powder prepared by the sol-gel method for the application of lithium ion battery anode materials, and discuss the electrochemical performance of high entropy oxides and the correlation between metal cations and materials, and test the electrochemical properties by simply changing the composition of the elements.
In terms of the results of the performance of lithium-ion batteries, the high entropy oxide anode material developed in this research has been tested by a lithium-ion half-cell, and its capacity reaches 600 mAh g-1 at a current of 50 mAh g-1. In addition, by changing the cation composition of the high entropy oxide, it can be further confirmed that entropy stability brings significant benefits to battery capacity and greatly improves cycle stability. In addition, high-voltage cathode (LMNO) was further used to test the battery system, which proved that the high entropy oxide will have the potential to replace current lithium-ion battery electrode materials in the future.

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