Development of High-performance Electric Double Layr Capacitor for Recovering/Reusing Inertia Energy of Heavy Vehicles

为了实现混合动力柴油车搭载活性炭电极制成的双层电电容器（EDLC）作为惯性能量回收装置，从而显著降低环境污染，我们对该电容器进行了静态和动态性能测试。研究总结如下：1。实验系统：我们开发了一套实验系统和一种方法，可以分别获得EDLC的静态和动态特性，这是常用的恒流充放电方法无法做到的。静态性能：测定了几种具有不同孔隙特征和不同表面特征的活性炭组成的EDLC的静态容量。比表面积的增加并不直接导致静态容量的线性增加。相反，表面积对容量只有轻微的影响。另一方面，表面氧化基团显著增加了静态钙离子的稳定性。动态性能：采用包含各种碳和电解质组合的“有效电导率”的模型，测量和分析了EDLC充放电的瞬态过程。当电极孔径超过0.7nm时，有效电导率显著提高。这一结果表明，当孔径在0.7nm左右时，离子以水合状态移动，当孔径小于临界孔径时，离子的移动受到孔几何结构的空间阻碍。从而发现并证实了电极碳孔隙特性的重要性。综合性能：适用于快速充放电的EDLC应具有0.8-0.9nm的孔径和表面氧化基团。较高的激活度只会使静态容量略有增加，而较低的激活度会导致动态责任的急剧下降。然而，人们必须注意活性炭表面氧化基团的稳定性，这方面的细节到目前为止还没有明确。少

Aiming at realizing a hybrid diesel car equipped with electric double layr capacitor (EDLC) made of activated carbon electrodes as an inertia energy recovery device, which can reduce environmental pollution significantly, we examined performance of the capacitor both for static and dynamic nature. Summary of the research follows below.1.Experimental system : We developed an experimental system and a method to obtain static and dynamic nature of EDLC separately, which cannot be made with the constant-current charge-discharge method of common use.2.Static performance : Static capacities of EDLC's composed of several activated carbons with various pore characteristics and with various surface characteristics were measured. Increase in specific surface area did not directly result in a linear increase in static capacity. Rather, the surface area showed only a slight influence to the capacity. On the other hand, it was the surface oxide groups that gave significant increase in the static ca … More pacity.3.Dynamic performance : Transient processes of charging/discharging EDLC was measured and analyzed with a model that includes an "effective conductivity" for various combinations of carbons and electrolytes. The effective conductivity was found to increase significantly if the pore width of electrode exceeded ca.0.7nm. This result implies that ionic species move as their hydrated states, whose sizes are around 0.7nm, and that the movement of the ionic species are sterically hindered by pore geometry if the pore width is smaller than a critical size. The crucial importance of pore characteristics of electrode carbon was thus found and confirmed.4.Total performance : The EDLC suitable for rapid charge/discharge should have pore width of 0.8-0.9nm and surface oxide groups. Higher degree of activation would give only slight increase in static capacity, and lower degree of activation would result in a drastic decrease in dynamic responsibility. One has to, however, pay attention to the stability of surface oxide groups on activated carbon, detail of which has not been clarified so far. Less