层次孔结构双功能碳负极材料的制备及性能

在500～900℃的活化温度下,以酚醛树脂为碳源,采用模板-物理活化联合法制备系列超级电容电池用层次孔结构双功能碳负极材料。借助扫描电镜、透射电镜及比表面积测试仪分析材料的物理结构,组装模拟电容器和对锂半电池,利用恒流充放电法及循环伏安法考察其电化学行为。结果表明:制备的层次孔结构碳材料具有较大的中微孔结构和局域石墨微晶结构;在LiPF6/EC+DMC和Et4NBF4/AN两种电解液中均表现出良好的电化学性能;其中以活化温度为600℃时制备的碳材料性能最优,其锂离子半电池可逆容量达到611.2 mA.h/g(0.2C),50次循环效率为74%,6C倍率下稳定可逆容量仍高达223 mA.h/g,模拟电容器比电容高达143 F/g(0.1 A/g),且倍率性能优异。

Preparation and properties of hierarchical porous graphitization carbon anode

A series of hierarchical porous graphitization carbon(HPGC) anode materials were synthesized for super lithium ion capacitor(SLIC) using phenolic resin as carbon precursor through physical activation-templating combined methods between 500-900 ℃.The structure of HPGC was investigated by SEM,TEM and nitrogen adsorption.The electric double layer capacitor and half-cell were fabricated to investigate the electrochemical performances of HPGC anode materials by charge-discharge of constant current and potential-sweep cyclic voltammetry.The results show that the macro-meso-microporous pore-size distribution and graphite microcrystalline structure of HPGC.The HPGC anodes exhibit good performance in both LiPF6/EC+DMC and Et4NBF4/AN electrolyte.The carbon material obtained at 600 ℃(HPGC-600) has the optimal electrochemical performance.The reversible charge capacity reaches 611.2 mA-h/g(0.2C),and the rate of capacity retention is 74% after 50 cycles.The reversible capacity at 6C is 225 mA-h/g.The capacitance of HPGC in capacitor reaches 143 F/g(0.1 A/g),and the rate performance is good.