海藻酸钙基凝胶电解质用于纤维超级电容器的连续化制备

Calcium Alginate Based Gel Electrolyte for Continuous Preparation of Fiber Supercapacitor

溶液挤出法能够连续化制备纤维储能器件,设计与开发高离子电导率的凝胶电解质是实现纤维储能器件一体化挤出的关键.使用海藻酸钙作为聚合物骨架,制备出海藻酸钙/硝酸锂凝胶电解质,其离子电导率高达145.3 mS/cm,并通过溶液挤出法实现了纤维超级电容器的连续制备.基于该凝胶电解质构建的纤维超级电容器,其电压窗口最高可以达到1.8 V,并在0.05~2.00A/g电流密度下均可正常工作.当纤维超级电容器的充放电电流密度由0.05A/g增加到0.50A/g,容量保持率为99.7%.经过1000圈的充放电循环后,纤维超级电容器的容量保持率为99.3%.通过优化凝胶电解质组分、纤维电极直径、凝固浴的浓度和温度,纤维超级电容器的制备速度可以达到20 m/min,最终能够连续构建长度超过3000 m的纤维超级电容器,有望应用于可穿戴电子器件领域.

Solution-extrusion method enables effective continuous fabrication of fiber energy storage devices.The design and development of gel electrolytes with high ion conductivities are the key to producing these fiber energy storage devices in a single step.Here,calcium alginate was used as the gel electrolyte framework to prepare a high-concentration calcium alginate/lithium nitrate gel electrolyte,which exhibited a high ion conductivity of 145.3 mS/cm.This gel electrolyte was extruded together with electrode inks via a spinneret and solidified by a coagulation bath,enabling a direct and continuous fabrication of fiber supercapacitors.The fiber supercapacitors based on this gel electrolyte could maintain high stability upon 1.8 V and stably work under current densities ranging from 0.05 A/g to 2.0 A/g.The current density of the fiber supercapacitor was increased from 0.05 A/g to 0.5 A/g,and the discharge capacity retention rate of fiber supercapacitor reached 99.7%.The resulting fiber supercapacitor could preserve 99.3%of the initial capacity after 1000 cycles.By adjusting the composition of gel electrolyte,structure of fiber electrode,concentration and temperature of coagulation bath,we had achieved a production speed of 20 m/min for continuous fiber supercapacitors with lengths over 3000 meters.This fiber supercapacitor is expected to serve as a power source for wearable electronic devices.