【摘要】：雙電層電容器(Electric Double Layer Capacitor,EDLC)是一種高效儲能元件。用于EDLC的電極材料多種多樣,其中煤基活性炭是最主要,效果最好的電極材料。將低階煤基無灰煤應(yīng)用于EDLC電極材料的制備中,既可以為低階煤的利用提供新途徑,又可以排除灰分對電容器性能的影響,提高EDLC的質(zhì)量比容量(以下簡稱比電容),能量密度等電化學(xué)性能。對無灰煤基活性炭的制備工藝與活性炭(ACs)孔結(jié)構(gòu)、電化學(xué)性能之間的關(guān)系進(jìn)行了系統(tǒng)的考察。通過對比原煤基活性炭(Coal-ACs)與無灰煤基活性炭(HPC-ACs)的各項參數(shù),分析了灰分對于ACs孔結(jié)構(gòu)和電化學(xué)性能的影響;以直接活化法和炭化-活化法分別制備ACs,通過調(diào)整制備過程中活化溫度(AT)、活化時間(At)、堿煤比(K/C)、炭化時間(Ct)和炭化溫度(CT)等工藝參數(shù),分析了制備條件對ACs孔結(jié)構(gòu)和電化學(xué)性能的影響。探討了比表面積、中孔率與孔徑分布對ACs比電容的影響。結(jié)果表明:無灰煤是制備EDLC電極材料的優(yōu)質(zhì)原料。以低階煤基無灰煤為原料所制備ACs灰分僅為0.36%,其比電容和倍率性均高于原煤基活性炭。改變ACs的制備條件可獲得不同孔徑分布的ACs。褐煤基無灰煤在AT為600℃,At為1.5 h,K/C為3:1的制備條件下,可獲得比表面積1473 m2/g,孔徑集中在0.58~0.73 nm之間的微孔活性炭。將該ACs用于EDLC中,其比電容和能量密度分別高達(dá)373.44 F/g和33.73 Wh/kg,且具有良好的倍率性,經(jīng)1000次循環(huán)后,比電容仍能維持在80%以上。炭化工藝對HPC-ACs的比表面積和孔徑分布有一定影響,但對其電化學(xué)性能的提高并不明顯。
[Abstract]:Double layer Capacitor (Electric Double Layer) is an efficient energy storage element. The electrode materials used for EDLC are various, among which coal-based activated carbon is the most important and most effective electrode material. The application of low-rank coal-base ashless coal to the preparation of EDLC electrode material can not only provide a new way for the utilization of low-rank coal, but also eliminate the influence of ash content on the performance of capacitor. Improve the mass specific capacity of EDLC (hereinafter referred to as specific capacitance), energy density and other electrochemical properties. The relationship between the preparation process of coal-free activated carbon and the pore structure and electrochemical performance of activated carbon (ACs) was systematically investigated. By comparing the parameters of raw coal based activated carbon (Coal-ACs) and ashless coal based activated carbon (HPC-ACs), the influence of ash on the pore structure and electrochemical performance of ACs was analyzed. Acs were prepared by direct activation method and carbonization activation method respectively. The activation temperature (AT), activation time (At), alkali coal ratio (K / C), carbonization time (Ct) and carbonization temperature (CT) were adjusted during the preparation process. The effects of preparation conditions on pore structure and electrochemical properties of ACs were analyzed. The effects of specific surface area, mesopore ratio and pore size distribution on the specific capacitance of ACs were discussed. The results show that ashless coal is a good raw material for the preparation of EDLC electrode materials. The ash content of ACs prepared from low-rank coal-free coal is only 0.36, and its specific capacitance and ratio are higher than that of raw coal-based activated carbon. ACS with different pore size distribution can be obtained by changing the preparation conditions of ACs. The activated carbon with a specific surface area of 1473 m2 / g and a pore size of 0.58 ~ 0.73 nm can be obtained from lignite-based ash free coal at an AT of 600 鈩，

本文編號：2152171