本研究製備鋰離子混成電容器，合成奈米碳管/錫/銅複合材料作為負極材料，搭配活性炭做為正極材料及鋰氟磷酸有機電解液，量測其性質。研究重點在於奈米碳管/錫/銅複合材料製備及搭配，其提供電容器的高能量密度特徵。
負極活性材料製備必先將疏水奈米碳管進行表面氧化，在使用無電電鍍的方式鍍上錫銅，得到奈米碳管/錫/銅粉末；另一方面，表面氧化的程序雖然會使奈米碳管導電率下降，但若不進行表面氧化的程序，錫銅無法還原在奈米碳管上，因此適當的表面氧化程序是必須的。利用XPS分析-*貢獻，做調整後得到適當氧化後的奈米碳管保有一定的導電能力，此外顯微形貌分析顯示奈米碳管被電鍍錫銅均勻包覆，並比較奈米碳管以及預鋰化完成的奈米碳管/錫/銅材料差異。所得的奈米碳管/錫/銅電極預鋰化，第一圈電量極高但含有高成分的不可逆量，1600 mAh g-1，第二圈電量約630 mAh g-1，第三圈電量570 mAh g-1，不可逆電量用於建立電極電解質介面(SEI)， SEI層的建立有助於穩定鋰離子嵌入電極及電容器的充放電。
此鋰離子混成電容器的比能量與比功率值，使用等電流放電曲線，我們製作三種不同重量比(AC:CNT/Sn/Cu = 3:1, 1.5:1, 1:1)進行測試，由Ragone plot圖可看出其中正負極比例為1.5/1進行電化學測試會得到比較優秀的表現，並探討各比例下，不同電流正負極電壓隨時間變化，而後進行交流阻抗分析，1.5:1電容器之等效電阻(1kHz)為5.98Ω。
此外不論比例為何使用0.1 A g-1進行充放電都會得到大約90 Wh kg-1左右的能量密度，由於負極進行鋰化去鋰化反應速率相較正極緩慢，是充放電的速率決定步驟，因此使用CNT/Sn/Cu作為負極的鋰離子混合式電容器適用低電流密度進行充放電。我們採用電化學性質最佳的正負極重量比1.5/1進行voltage hold測試，維持在高電壓3.8V共100小時，一百小時後的電容保留率大約為85%。庫倫效率維持在95%以上。

In this study, lithium hybrid ion capacitors, consisting of a negative electrode of CNT/Sn/Cu composite and activated carbon positive electrode soaked in LiPF6/EC:DMC electrolyte, were prepared, starting from the CNT/Sn/Cu composite synthesis and ended with the capacitor performance measurements. The research efforts are focused on fabrication of the CNT/Sn/Cu anode and its mass balancing with AC. The CNT/Sn/Cu anode renders the capacitor feature of high energy.
On synthesis of CNT/Sn/Cu anode, the carbon nanotube surface has to be oxidized before electroless plating of tin and copper is executed, since the carbon surface is hydrophobic. On the other hand, the excessively oxidized surface conducts poorly. The oxidation conditions were adjusted to obtain the properly oxidized surface using the -* contributing of XPS spectra such that we maintained the CNT conductive capability at certain level. Microstructure analysis indicates the metallic tin and copper wrap the nanotube uniformly, and compares the morphological difference between the coated nanotubes and the lithiated nanotubes. The so-prepared electrode exhibits huge capacity, 1600 mAh g-1, that contains a large fraction of irreversibility in the first discharge cycle of prelithiation. The second cycle, 640 mAh g-1, and the third cycle 570 mAh g-1, are highly reversible. High reversibility in the first cycle is due to lithium consumed in building the solid-electrolyte interface (SEI). The SEI formation stabilizes the lithium intercalation and charge-discharge cycling.
Values of specific energy and power of the lithium hybrid ion capacitors are calculated, based on the galvanostatic discharge curves, with a AC:CNT/Sn/Cu mass ratio of 3:1, 1.5:1, 1:1. Ragone plots of these three cells show 1.5:1 is the best mass ratio in energy-power performance. We analyze the electrode potential variation with time for the three cells under different specific currents. The resistances of three cells are also measured with impedance spectroscopy. The equivalent resistance of 1.5:1 cell is 5.98Ω.
Regardless the mass ratios, these capacitor demonstrates storage capacity of 90.0 Wh kg-1 and 0.16 kW kg-1 at 0.1 A g-1. Since the anode mass loadings of three cells are the same, we infer that the cell performance is governed by the CNT/Sn/Cu electrode, which is reasonable since lithiation and delithiation is intrinsically slow compared with adsorption on double layer, hence rate-determining. We also measure the stability of 1.5:1 cell using the voltage hold method, which displays 85% retention in capacitance and over 95% coulombic efficiency in a period of 100 h.

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