高比电容少层碳电极材料及高电压水基电解液的研究

Electrochemical capacitors represent an attractive technology for energy storage and mobile power supply, but are limited by relatively poor energy density by using economically viable materials and fabrication technologies. The electrode material and electrolyte are the key factors for the electrochemical capacitors. Based on our recent research results published on Science, our research proposal focuses on the mesoporous doped few-layer carbon and high-voltage electrolyte. The main content in the research proposal includes three points: (i) With a materials genome initiative, we will design and prepare porous few-layer doped carbon with a most extraordinary capacitance of 1000 F/g and withstand 30,000 charging/discharging cycles, and then summarize some relationships between the performance and its crystal structure and microstructure; (ii) We design a strategy to obtain high-voltage aqueous electrolyte with voltage over 2.5V, by adjusting and controlling electronic structure and ionic activity; (iii) Based on the quantitative structure-property relationship, we develop the ideal material with multi-pair redox reactions for pseudocapacitor through mixing monomers with single-pair redox, to deal with the problem of capacitance loss for pseudocapacitive material with a pronounced redox peak in symmetric electrochemical capacitor, and finally obtain the packaged electrochemical cells featuring a specific energy of over 40 Wh/kg.

超级电容器具有功率密度大、寿命长、安全可靠等特点，但其工作电压和能量密度过低，无法满足大规模储能需求。电极材料和电解液是决定其能量存储性能的关键。本项目在现有的研究基础之上，聚焦掺杂型多孔少层碳电极材料及其匹配的高电压水基电解液，主要开展的研究包括：（1）发展比电容大于1000 F/g、循环寿命大于30,000次的掺杂型多孔少层碳电极材料的结构-性能设计理论模拟方法与制备技术；通过储能电化学机理研究，揭示高能量和高功率的协同机制及动力学和热力学科学内涵；（2）经电子结构、离子活度及界面微观动力学调控，研发电压大于2.5 V的高电压水基电解液，突破水基电解液分解电压的热力学理论极限；（3）基于结构-性能关系，开发含有多对氧化还原反应的复合赝电容材料，获得具有理想电化学特性的电极材料及能量密度大于40 Wh/kg的验证型器件。

超级电容器具有功率密度大、寿命长、安全可靠等特点，但其能量密度过低，限制了其应用范围。电极材料和电解液是决定器件能量存储性能的关键。为此，本项目聚焦高容量高导电电极材料及其匹配的高电压水基电解液的设计制备，主要开展的研究包括：（1）提出了高容量高导电电极新材料的设计规则，发展了掺杂型多孔少层碳电极材料的结构-性能设计理论模拟方法与制备技术，研发电压大于2.5 V的高电压水基电解液；（2）建立了原子力显微镜-拉曼光谱联用、电化学石英晶体微天平这两类电化学储能机理原位表征新方法，揭示高能量和高功率的协同机制及动力学和热力学科学内涵；（3）基于结构-性能关系，开发低内阻器件结构，获得功率密度大于15 kW/kg、能量密度大于60 Wh/kg的新型储能验证器件，为下一代高能量和高功率储能器件的研发提供理论依据和技术支撑。