| 高性能二次锂硫电池正极材料的研究 |
| 朱绍银
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| 2016-08
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关键词 | 表面修饰
正极材料
凝胶电解质
穿梭效应
锂硫电池
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学科分类 | 能源材料
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报告类别 | 专题报告
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中文摘要 | The cells performance of second lithium-sulfur batteries was determined by the cathode properties to a large extent. Therefore, it is necessary to improve the electrochemical performance of cathode materials for lithium-sulfur batteries. Herein, we mainly try to improve the electrochemical properties of cathode materials through the reasonable design and modification of cathodes components (such as carbon materials, binder), and try to establish the structure-function relationship between structure modification and electrochemical properties. Solutions presented in this article are summarized as follows:
1. An activated carbon with enriched amine groups was prepared by carbonizing the polyimide wastes. The prepared cathodes basing on the carbon/sulfur composites have an excellent electrochemical performance at low temperature. Under the condition of -20 °C, the specific capacity of 368 mAh g-1 (0.5 C) was achieved after 100 cycles. At the room temperature (25 °C), the as-prepared cathodes show the retained specific capacity of 620 mAh g-1 (0.5 C) after 350 cycles with a low capacity-decay rate (0.071% per cycle). The excellent electrochemical performance at low temperature and room temperature is mainly attributed to the enriched amine groups with good chemical adsorption to polysulfides.
2. In order to decrease the crystallization properties inside polymers as gel hosts of polymer gel electrolyte, a small molecule gel with flexible design and no crystallization was synthesized to prepare small molecule gel electrolyte (sGE). The primary possibility as electrolyte materials in lithium-sulfur batteries was explored. The prepared small molecule gel electrolyte shows an ionic conductivity of 6.43×10 -3 Scm-1 at room temperature. The prepared cathode with this small molecule gel electrolyte shows a discharge capacity of 1008 mAh g-1 (0.1 C) in primary cells. |
英文摘要 | 锂硫电池正极材料的性能在很大程度上决定着二次锂硫电池的电池性能,因此研究如何提高锂硫电池正极材料的电化学性能具有重要的科学意义和应用价值。本论文主要通过对正极材料各组分(如碳材料、粘结剂)的合理设计及改性来提高正极材料整体的电化学性能,并建立材料的结构改性与电化学性能之间的构效关系。
本文的主要结论:
1. 以聚酰亚胺废料为原料制备了一种富含胺基的活性炭材料,用其制备的碳硫复合材料作为锂硫电池正极具有优异的低温电化学性能。在-20℃条件下,循环100圈之后仍保持368 mAh g-1(0.5C)的容量。室温25℃条件下,制备的硫正极表现出良好的循环可逆性,循环350圈之后能保有620 mAh g-1(0.5C)的容量,每一圈的容量衰减为0.071%。该正极优异的低温和常温电化学性能主要归因于材料表面丰富的胺基对聚硫阴离子起到了良好的化学吸附作用。
2. 为了消除聚合物凝胶电解质中聚合物自身的结晶特性,我们制备了一种小分子凝胶电解质材料,初步探索了有机小分子凝胶作为锂硫电池电解质材料的可能性。制备的小分子凝胶电解质在常温下具有6.43×10-3 S cm-1的离子电导率,用其制备的一次锂硫电池正极的放电容量也有1008 mAh g-1(0.1 C)。 |
文献类型 | 研究报告
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条目标识符 | http://ir.qibebt.ac.cn/handle/337004/9808
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专题 | 先进界面技术研究组
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推荐引用方式 GB/T 7714 |
朱绍银. 高性能二次锂硫电池正极材料的研究. 2016.
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文件名:
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高性能二次锂硫电池正极材料的研究.pdf
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Adobe PDF
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