陰離子嵌入碳材於非對稱超高電容器之研究

A study on anions intercalation into carbons for asymmetric supercapacitors

黃銘鋼(Huang, MingGang)

指導教授 ： 胡啟章

國立清華大學/工學院/化學工程學系/碩士(2015年)

摘要

摘 要
本論文旨在研究陰離子嵌入碳材的電化學行為，基於此儲能機制設計非對稱超高電容器。
第一部份，將應用在燃料電池中作氣體擴散層的碳紙(GDL25BC)作為電極，用於研究陰離子嵌入碳材的電化學行為。搭建三電極測試系統和電解液體系，測定碳紙正極上的電化學反應並與材料分析結果做比對。我們得到的結論：1.碳紙(GDL25BC)通過陰離子嵌入儲能是高比容量且倍率性好的電極材料；2. 碳紙(GDL25BC)經滾壓處理，可以製成可繞式電極。3.可繞式碳紙電極高倍率循環穩定性好。
第二部份，通過商業石墨型碳材的陰離子嵌入行為研究得出：1.陰離子嵌入行為需在高石墨結晶度碳材中才發生，軟碳並不可行；2.顆粒尺寸會影響電極的電荷傳輸阻抗（Rct）和Warhurg擴散阻抗，大粒徑的材料其倍率性能制約很大。3.中間相碳微球（MCMB）既有高結晶度，又擁有非晶相炭峰。這些非晶相炭使得電解質更好地在電極中擴散傳輸，電極的倍率性能得到極大改善。
第三部份，依據上述結論選擇蠕蟲結構的膨脹石墨作為新型正極，並對膨脹石墨做熱處理、超聲波振蕩、瀝青碳包覆和酚醛樹脂包覆改性處理。得到性能最佳的EG-600Up（膨脹石墨經600℃處理，超聲波振蕩4h ，75%瀝青碳包覆），具有高倍率性能（3A/g）及充放電穩定性 (500cycle，95.7% 容量保持)。將此材料作為正極，活性炭負極，溶有四氟硼酸四乙基銨（TEABF4）的碳酸丙烯酯(PC)作電解液組裝成非對稱超高電容器（AC/EG-600Up）。此電容器的電能量密度和功率密度可達： 51.47Wh/kg，10.12kW/kg。

關鍵字

超級電容器 ； 非對稱 ； 陰離子嵌入

並列摘要

Abstract
The thesis aims at studying the electrochemical behavior of anion intercalation into carbon materials and designing the asymmetric supercapacitors based on this energy storage mechanism.
The first part introduces using carbon paper (GDL25BC), which is a gas diffusion layer in fuel cell, as an electrode for studying the electrochemical behavior of the anion intercalation. A three-electrode test system with electrolytes system was established and comparaed the electrochemical reaction on the carbon paper positive electrode with results of material analysis in this section. In conclusion: 1. Anion intercalation type carbon paper (GDL25BC) is a high specific capacity and good rate-performance electrode; 2.Carbon paper (GDL25BC) by the rolling process, can be made to flexible electrode. 3. It has a high rate performance and good cycling stability.
The second part demonstrates comparing the electrochemical behavior of anion intercalation into commercial graphitic carbons. In summary: 1. Anion intercalation need occur at graphitic carbon materials with a high crystallinity degree, so that the soft carbon is not allowed; 2 Particle size affects on the electrode through charge transfer impedance (Rct) and Warburg diffusion impedance, a large particle size material greatly restricts its rate performance. 3. Mesosphere carbon microbeads (MCMB) has a high crystallinity degree, but also amorphous carbon peak. These amorphous carbon promote electrolyte diffusion transfer in the electrode, so that the electrode performance ratio has been greatly improved.
In the third part, worms-like type expanded graphite was selected as new cathode based on the above conclusions. Modify expanded graphite by heat treatment, ultrasonic vibration, pitch carbon coated and phenolic resin coated. Get the best performance sample EG-600Up (expanded graphite treated treatment at 600 ℃, ultrasonic oscillation 4h, 75% pitch coated), it has a high rate capability (3A / g) and discharge stability (500cycle, retention 95.7%). Assembled asymmetric supercapcitors (AC /EG-600Up) which activated carbons as a negative electrode, EG-600Up as a positive electrode, measured in TEABF4 solving in propylene carbonate (PC). It has a good performance on energy density and power density: 51.47Wh / kg, 10.12kW / kg.

並列關鍵字

Supercapacitor ； Asymmetric ； Anion intercalation

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