Abstract: Supercapacitor is a new type of green energy storage device with high power density,long life cycle,and wide range of working temperatures. However,its energy density is quite low and is less than 1/10 of the advanced lithium ion batteries are. The low energy density of traditional supercapacitors is the main reason of their limted applications. For the traditional supercapacitor,the elements limiting the energy density include that:①only the surface materials of the electrode is used for the reaction;②the potential of electrode continuously changes during the charge and discharge processes;③the ions in the electrolyte get consumed during the charge process. As a result,reducing the consumption of ion in the electrolyte and improving the capacity of electrode become the effective measures to solve the problem of low energy density. And it includes the hybrid structure and lithium ion structure. Since the negative electrode can work as the source of lithium,lithium ion battery can choose much more different positive electrode materials and open the new gate for the researches.

Key words: supercapacitor, energy density, electrolyte, capacity, lithium-ion supercapacitor

摘要： 介绍了超级电容器是一种新型的绿色能量存储装置，具有高功率、良好循环寿命和工作温度范围广等优点，但是其能量密度较低，甚至达不到新型锂离子电池能量密度的十分之一，成为了限制超级电容器应用的主要问题。文章指出传统超级电容器能量密度限制因素包括：仅电极表面活性物质参与反应，电极电势充放电过程中会不断变化，以及充电过程中电解液离子的消耗等。减少电解液中离子的消耗与提升电极容量成为了解决能量密度较低的有效措施，目前研究的重点包括采用混合型结构、锂离子型结构的超级电容器等。文章指出锂离子电容器结合了传统双电层电容器和锂离子电池的优势，在保持高功率密度的同时提升了能量密度，是一种极具发展前景的混动和纯电动汽车电源。由于预嵌锂的负极也可作为锂的来源，因而锂离子电池可以选择更多的正极材料，从而开启了锂离子电池研究的新大门。

关键词: 超级电容器, 能量密度, 电解液, 容量, 锂离子超级电容器