摘要锂硫电池由于其高理论能量密度(2567 Wh/kg)和其高比容量(1675 mAh/g),低成本,以及对环境无污染等特点,被认为是最具前景能量储存器件之一。但是目前Li-S电池的实际应用还有许多困难,例如:硫本体材料的导电性非常差,其放电产物(Li2S / Li2S2)的利用率非常低;其次,长链多硫化锂(Li2Sn,4≤n≤8)在反应中易溶于电解液,溶解的多硫化锂在循环过程中容易迁移至负极材料表面,使负极锂腐蚀的同时,还造成电池的自放电现象,造成的穿梭效应严重制约了锂硫电池的发展。为了改善以上的问题,提高锂硫电池的循环稳定性,本文采用改进了的humans法和热处理制备氧化石墨烯,化学法制备多硫化钠,在石墨烯/碳纳米管(GO/CNT)表层负载活性硫(GO/CNT/S),以GO/CNT为下层,GO和GO/CNT/S为上层进行抽膜。以GO/CNT为间层,防止Li2Sn的穿梭。极大地提高了硫的循环稳定性能。41063
毕业论文关键词:碳纳米管 石墨烯 薄膜 柔性 锂硫电池
The preparation of carbon - sulfur composite film material and its lithium storage performance study
Abstract
Lithium-sulfur batteries because of its high theoretical energy density (2567 Wh / kg) and its high specific capacity (1675 mAh / g), low cost, and environmental pollution, etc., is considered one of the most promising energy storage device. But now the practical application of Li-S battery there are many difficulties, such as: sulfur-conductive body material is very poor, the discharge product (Li2S / Li2S2) utilization rate is very low; secondly, lithium polysulfide long chain (Li2Sn, 4 ≤n≤8) in the reaction is soluble in the electrolyte, lithium sulfide dissolved in the multi-cycle process is easy to migrate to the surface of the negative electrode material, the lithium negative electrode corrosion, while also causing the battery self-discharge phenomenon caused serious effects shuttle It restricted the development of lithium-sulfur battery. In order to improve the above problems and improve the cycling stability of lithium-sulfur batteries, paper, humans improved method and heat treatment for preparing graphene oxide, chemically prepared sodium polysulfide, graphene / carbon nanotube (GO/CNT) surface load active sulfur (GO/CNT/S), in order to GO/CNT is lower, GO and GO/CNT/S was evacuated for the upper membrane. In GO/CNT interlayer prevents Li2Sn shuttle. Greatly improve the cycle stability of sulfur.
Key words: carbon nanotubes graphene oxide flexible porous hybrid film
目录
摘要-Ⅰ
Abstract--Ⅱ
目录-Ⅲ图清单Ⅵ
1 前言-1
2 实验部分-3
2.1实验试剂 -3
2.2仪器设备 -3
2.3实验步骤 -3
3 结果与结论-5
4结论9
参考文献10
致谢13
图清单
图序号 图名称 页码
图1 CCS薄膜示意图 5
图2 CCS薄膜及其柔性的光学图 6
图3 CCS薄膜材料作为锂硫电池正极材料的循环伏安曲线图 7
图4 CCS薄膜电极材料的充放电曲线 7
图5 CCS薄膜电极在多次循环过程中的容量变化情况及其相应的库伦 8
1前言
由于人口与经济的增长和生活方式的进步,能源的需求稳步增长,能源使用量也相应的增加,环境污染和化石燃料的使用也越来越严重。为了减轻这些问题,减少我们对化石燃料的依赖,发展清洁能源和新型的能源储存体系是解决能源问题和环境问题的一个有效手段,例如太阳能和风能。然而太阳能和风能是间歇的,因此,通过可再生能源制备电子储存器是必不可少的。充电电池是电子储存器最可行的选择之一。目前,铅酸电池、镍镉电池、镍氢电池、锂离子电池广泛的应用于各种程序中,例如便捷式电子设备、电动汽车、航天飞行器以及电网运输等方面。随着便捷式电子功能变得更加复杂和对电动车的需要,相应的可再生能源的储存也需要逐渐增加,先进的充电电池也需要发展。其中重要的参数是成本、能源、循环寿命、安全和环境兼容性。 碳硫复合薄膜材料的制备及其储锂性能研究:http://www.751com.cn/huaxue/lunwen_40997.html