Development of Design Model of Electric Double-Layer Capacitors as All-Purpose Energy Recovery Devices for Reducing COィイD22ィエD2 Emission

作为减少CO2D22排放的通用能量回收装置的双电层电容器设计模型的开发

• 批准号: 10555266
• 负责人: MIYAHARA Minoru
• 金额: $ 5.06万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10555266/
• 关键词: Activated Carbon; Electric Double Layer Capacitor; Charge; discharge; Energy Recovery; Nernst-Planck Equation; Nanopores; Electric Capacity

Electric double-layer capacitor (EDLC) is expected to stand as an all-purpose energy recovery device for reducing carbon dioxide emissions. For reasonable and reliable use of the EDLC with activated carbon electrodes, a model for describing both equilibrium and kinetic characteristics of the EDLC must be established. This research project pursued charging/discharging behavior of EDLC and obtained the following results.1.Characterization : Employing nitrogen adsorption, we determined pore-sizes, micropore volumes, micropore surface area of high-surface-area activated carbons with different degree of activation. Pore sizes ranged form 0.6-1.0 nm, which compare with the sizes of hydrated ions in aqueous solution.2.Equilibrium : Static capacities -- not the apparent ones by constant current charge measurement -- of EDLC's composed of activated carbons with various pore characteristics and with various surface characteristics were measured successfully by monitoring electric current after p … More otential disturbance. The carbons employed were found to have significantly larger capacities than those of activated carbon fibers with similar surface areas. This characteristics are thought to come from the random nature of the interior surface of the alkali-activated carbons used.3.Kinetics : Transient processes of charging/discharging EDLC was successfully measured with on-line based experimental system constructed in this study. We succeeded in modeling the charging/discharging behavior. The model employed the Nernst-Planck equation for describing anions and cations, and included electric resistance of the carbon electrodes. The time constants obtained through the analysis showed that a small difference in pore diameter near the size of hydrated ions drastically changes the mobility of the ions probably because of steric disturbance in the movement of ions. Further, it was made possible to predict the effect of various resistances onto the total performance of the charge/discharge ability of capacitors.Through all the above study, a model for predicting performance of EDLC based both on equilibrium and kinetic characteristics has been successfully established, and showed usefulness as a design tool for activated carbon EDLC. Less

双电层电容器（EDLC）有望成为减少二氧化碳排放的通用能量回收装置。为了合理可靠地使用活性炭电极双电层电容器，必须建立一个描述双电层电容器平衡和动力学特性的模型。本研究对双电层电容器的充放电行为进行了研究，得到了以下结果：1.表征：采用氮气吸附法测定了不同活化程度的高比表面积活性炭的孔径、孔容、比表面积。2.平衡：采用恒电流充电法，通过对不同孔特征和表面特征活性炭的放电后电流的监测，成功地测定了由不同孔特征和表面特征活性炭组成的双电层电容器的静态电容，而不是恒电流充电法测得的表观电容 ...更多信息 潜在的干扰所采用的碳被发现具有显着更大的容量比那些具有类似的表面积的活性炭纤维。这种特性被认为是来自于所使用的碱活性炭的内表面的随机性质。3.动力学：本研究构建的基于在线的实验系统成功地测量了双电层电容器充/放电的瞬态过程。我们成功地模拟了充电/放电行为。该模型采用能斯特-普朗克方程描述阴离子和阳离子，并包括碳电极的电阻。通过分析获得的时间常数表明，水合离子尺寸附近孔径的微小差异会极大地改变离子的迁移率，这可能是由于离子运动的空间干扰。通过以上研究，成功地建立了基于平衡特性和动力学特性的双电层电容器性能预测模型，为活性炭双电层电容器的设计提供了有用的工具。少