本研究使用迴流法合成出各種不同金屬基的磷酸鋰金屬鹽前驅物，再經熱處理使相變化成橄欖石結構的磷酸鋰基金屬鹽粉末。不同金屬基的前驅物有著不同的形貌，其中LiFePO4前驅物及LiFe0.5Mn0.5PO4前驅物為花瓣片狀，LiMnPO4前驅物為立體連續絲綢片狀，LiFe0.4Mn0.4Ni0.2PO4前驅物為矩形片狀。本研究特別深入分析未知的LiMnPO4前驅物組成相，發現片狀前驅物之任意局部區域皆為多種晶相與非晶相共存。
橄欖石結構的磷酸鋰基金屬鹽有著電子導電性質不佳及鋰離子傳輸能力低的缺點，本研究磷酸鋰基金屬鹽粉末的特殊片狀結構可以縮短鋰離子的傳輸路徑，預期應可改善鋰離子傳輸特性。
此外，本研究使用不同碳源包碳以改善LiFe0.5Mn0.5PO4的電子導電性，未最佳化蔗糖包碳的LiFe0.5Mn0.5PO4在0.1 C放電電流下有接近150 mAh/g的放電比電容表現，達到理論比電容的88 %。而PS+GO包碳可以更有效地增加LiFe0.5Mn0.5PO4的導電性質，降低極化效應，使在大充放電流情況下表現較好。且發現LiFe0.5Mn0.5PO4的放電曲線為三個放電斜坡，而非兩水平放電平台，顯示其放電機制並非為獨立的磷酸鋰鐵及磷酸鋰錳兩區分別放電，而是在同時含有鐵錳元素的LiFe1-xMnxPO4進行鋰離子的嵌入脫出。

Various nano-flake precursors of transition metal lithium orthophosphates were successfully prepared by chemical reflux method in this study. The precursors can be transformed into LiXxYyZzPO4 (where x+y+z=1) with olivine structure via annealing. Different precursors have different shapes. LiFePO4 precursor and LiFe0.5Mn0.5PO4 precursor are flower-like flake shape, LiMnPO4 precursor is 3D continuous silk-like flake shape, and LiFe0.4Mn0.4Ni0.2PO4 precursor is rectangular or square sheet. LiMnPO4 precursor was characterized with various instruments.The results showed that every local area of LiMnPO4 precursor is composed of various kinds of crystals as well as amorphous phase.
The shortcomings of the transition metal lithium orthophosphates include poor electronic conductivity and low ionic transport. The nano-sheet shape in this study can shorten the lithium ion transport path to enhance the deintercalation/intercalation of lithium ions.
In this study, carbon coating with different carbon sources was used to improve the electronic conductivity.The battery assembled with sucrose coated, which was not optimized, LiFe0.5Mn0.5PO4 could deliver around 150 mAh/g at 0.1 C discharge rate.This value reached ~88% of the theoretical capacity. Carbon coating with PS+GO could further improve the electronic conductivity of LiFe0.5Mn0.5PO4 and reduce the polarization effect so as to enhance capacity performance at large discharging rate. In addition, the characteristic discharging curve showed three slopes rather than two plateau-areas indicated discharging is not resulted solely from LiFePO4 and LiMnPO4 independently.The lithium ions should be inserted to/extracted from the LiFe1-xMnxPO4 powder containing both Fe and Mn.

摘要 I
Abstract II
目錄 III
表目錄 V
圖目錄 VI
第一章 緒論 1
1.1 前言 1
1.2 鋰離子電池相關電化學原理 3
1.2.1 鋰離子電池充放電工作原理 3
1.2.2 磷酸鋰鐵錳之相關電化學分析理論 4
1.3 研究架構及想法 12
第二章 文獻回顧 14
2.1 鋰離子電池簡介及不同過渡金屬之磷酸鋰基金屬鹽的特性比較 14
2.2 磷酸鋰鐵錳之特性及放電相變理論 20
2.3 磷酸鋰基金屬鹽改質方式 26
2.3.1 縮小粒徑尺寸降低鋰離子傳輸路徑 26
2.3.2 包覆導電碳增加導電度 36
第三章 實驗方法 48
3.1 磷酸鋰基金屬鹽前驅物合成 48
3.2 前驅物球磨包碳及熱處理製備磷酸鋰基金屬鹽 48
3.3 電池製作 49
3.4 材料分析及鑑定 51
3.4.1 X光繞射儀 51
3.4.2 場發射掃描式電子顯微鏡配備元素微分析系統(Field Emission Scanning Electron Microscope with EDS) 52
3.4.3 拉曼光譜儀 52
3.4.4 場發射掃描穿透式球差修正電子顯微鏡 53
3.4.5 感應耦合電漿放射光譜儀 53
3.4.6 電池測試 53
3.5 實驗架構流程 54
3.6 實驗藥品 55
3.7 實驗儀器及設備 56
第四章 結果與討論 57
4.1 前驅物材料分析鑑定 57
4.1.1 前驅物SEM分析 57
4.1.2 前驅物XRD繞射圖 61
4.1.3 磷酸鋰錳前驅物TEM分析 89
4.2 無另行包碳之橄欖石結構磷酸鋰基金屬鹽粉末分析 99
4.2.1 橄欖石結構磷酸鋰基金屬鹽粉末SEM分析 99
4.2.2 橄欖石結構磷酸鋰基金屬鹽粉末XRD分析 102
4.2.3 橄欖石結構磷酸鋰基金屬鹽及其前驅物粉末ICP分析 105
4.2.4 TEM分析–鋰離子通道方向(b軸) 108
4.2.5 磷酸鋰鐵錳EDS分析 113
4.3 不同包碳碳源之LiFe0.5Mn0.5PO4比較 115
4.3.1 Raman光譜分析結果 115
4.3.2 SEM形貌比較 117
4.3.3 XRD繞射圖譜比較 120
4.3.4 TEM碳膜觀察分析 120
4.4 電池測試結果分析(LiFe0.5Mn0.5PO4) 123
4.4.1 LiFe0.5Mn0.5PO4 － 未最佳化蔗糖包碳 124
4.4.2 LiFe0.5Mn0.5PO4 － PS+GO包碳 127
4.5 兩種磷酸鋰鹽前驅物混合燒結與單一前驅物燒結之磷酸鋰鐵錳的比較 130
第五章 結論 132
第六章 參考文獻 133

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