Novel Supercapacitors with Ultrahigh Energy Densities

PI：Shaw，LeonProposal编号：1234976机构：康涅狄格大学标题：具有超高能量密度的新型超级电容器电动汽车和可再生能源的发展要求储能系统同时具有高能量密度和功率密度，以及优越的循环寿命和低成本。众所周知，电池通常提供高能量密度但具有低功率容量，而电容器通常具有高功率密度但具有低能量容量。然而，随着电动汽车的广泛市场渗透，特别是插电式混合动力汽车和所有电动汽车，长距离行驶需要高能量密度，而快速充电需要高功率密度。因此，现有的存储技术无法同时满足对高能量密度和高功率密度的日益增长的需求。本项目就是为了解决这些问题而提出的。在本项目中，将研究和开发新一代电化学电容器，也称为超级电容器(SCs)。通过电极结构的创新设计和制造，将建立组装SC的关键原则，使其具有与电池相当的比能量(~85Wh/kg)，同时具有超高倍率性能(即在几分钟内充放电)。当下一代电极化学和纳米结构设计出现时，这些基本原理可以在未来应用于构建具有更高比能量的干细胞。电极化学和纳米结构的最新进展表明，如果仅基于活性电极材料计算能量密度，那么具有与电池相似的高能量密度(例如，85Wh/kg)是可能的。然而，仅基于活性电极材料的高能量密度很难转化为具有类似高能量密度的组装器件。与锂离子电池一样，组装的SC除了电极外，还包括集流器、电解液、隔膜、粘合剂、连接器和封装。因此，组装的器件的能量密度通常比活性材料的能量密度低3到4倍或更多。本项目中提出的正负电极互穿的SCS将准确地解决这一具有挑战性的问题。由于电极结构的创新设计，可以使电极的厚度、宽度和高度尽可能大，直到电子传导性成为速率限制。有了这项变革性的技术，PI将把基于有源电极材料的高能量密度转换为用于组装设备的相当高的能量密度。该项目的广泛影响将体现在三个方面。首先，具有前所未有的能量密度和优越的倍率性能的新一代SC有望彻底改变储能领域，加快电动汽车的市场渗透和可再生能源的利用，使国家实现重大飞跃，确保S长期的能源安全和清洁的环境。其次，该项目将为一名研究生和许多本科生提供良好的能源储存和替代能源领域的教育和培训机会。第三，该项目将为有关纳米制造和替代能源的公共教育做出贡献。

PI: Shaw, LeonProposal Number: 1234976Institution: University of ConnecticutTitle: Novel Supercapacitors with Ultrahigh Energy DensitiesDevelopment of both electric vehicles and renewable energy requires energy storage systems that have high energy density and power density simultaneously with superior cycle life and low cost. It is well known that batteries typically provide high energy densities but with low power capacities, whereas capacitors normally have high power densities but with low energy capacities. However, for widespread market penetration of electric vehicles, particularly for plug-in hybrid vehicles and all electrical vehicles, high energy density is required for long driving distance, while high power density is needed for rapid recharge. Thus, the growing need for both high energy density and high power density cannot be met simultaneously with the existing storage technology. This project is proposed to solve these problems.In this project, a new generation of electrochemical capacitors, also termed supercapacitors (SCs), will be investigated and developed. Through innovative design and manufacturing of the electrode architecture, the key principles for making assembled SCs that have specific energy equivalent to those of batteries (~85 Wh/kg) while possessing ultrahigh rate performance (i.e., charging and discharging in a few minutes) will be established. These underlying principles can be applied in the future to construct SCs with even higher specific energies when the next-generation design of the electrode chemistry and nanostructure becomes available. Recent advancements in the electrode chemistry and nanostructure have revealed that SCs with high energy densities similar to those of batteries (e.g., 85 Wh/kg) are possible if the energy density is computed based on the active electrode materials alone. However, the high energy density based on the active electrode materials alone is very difficult to be translated into assembled devices with the similar high energy density. Assembled SCs, like Li-ion batteries, contain current collectors, electrolyte, separator, binder, connectors, and packaging, in addition to the electrodes. As a result, the energy density of an assembled device is typically lower than that of the active material by a factor of 3 to 4 or more. The proposed SCs in this project with interpenetrating positive and negative electrodes will solve this challenging problem precisely. Due to the innovative design of the electrode architecture, the thickness, width and height of electrodes can be made as large as possible until electronic conductivity becomes rate limiting. With this transformative technology, the PI will convert the high energy density based on the active electrode material into a comparable high energy density for an assembled device. The broad impact of this project will manifest in three fronts. First, the new generation SCs with unprecedented energy densities and superior rate performance are expected to revolutionize the field of energy storage and expedite the market penetration of electric vehicles and utilization of renewable energy, enabling major leaps to ensure our nation?s long-term energy security and a clean environment. Second, this project will provide excellent education and training opportunity to one graduate student and many undergraduate students in the areas of energy storage and alternative energy. Third, this project will make contributions to public education about nano-manufacturing and alternative energy.