电极制备工艺对褐藻多孔碳双电层电容性能的影响

摘要

To study the possible changes in the electrical double-layer capacitance ( EDLC ) of materials during electrode processing, effects of carbon particle size and electrode pressure on the electrical double-layer capacitors (EDLCs) were studied using brown algae as porous carbon precursors. The carbon powder was ground and sieved into five groups with different particle size distributions, and then used as electrodes. The following electrochemical tests including charge-discharge curves and cyclic voltammetry show that the specific capacitance of the electrodes notably increases with the decrease of carbon particle size, and peaks at 10 MPa with the increase of pressure. Under the conditions of this paper, the parameters of carbon particle size less than 25 μm and processing pressure of 10 MPa ( correspondingly, the real pressure added on electrodes is around 619 MPa) provides the best capacitive performance among all the samples.%为探究电极制备过程对材料双电层电容可能带来的变化,以褐藻为前驱体制备多孔碳,研究了电容测试过程中碳颗粒尺寸和电极制片压力两种工艺参数对其双电层电容性能的影响规律.通过将多孔碳粉末严格筛分成5组不同的尺寸,分别制成电极并测试其充放电性能和循环伏安曲线,得到比电容随颗粒尺寸变化的规律;再选取优化尺寸的多孔碳,在4种不同的压力下制成电极片,进而研究了不同制片压力对电极电容的影响规律.研究表明,在微米级,所制电极的比电容随碳颗粒尺寸的减小显著增加,同时随制片压力的增大,比电容先增大后减小.本实验条件下,碳颗粒尺寸小于25 μm、制片压力为10 MPa(对应电极片所受真实压强约619 MPa)时,得到的电极片具有最高的比电容值.