Different types of pre-lithiated hard carbon as negative electrode material for lithium-ion capacitors
Different types of pre-lithiated hard carbon as negative electrode material for lithium-ion capacitors
复制标题
DOI：
10.1016/j.electacta.2015.11.055
复制
发表时间：
2016-01-01
影响因子：
6.6
通讯作者：
Shi, Zhiqiang
中科院分区：
文献类型：
--
作者：
Zhang, Jin;Liu, Xifeng;Shi, Zhiqiang
锂离子电容器（LIC）由活性炭（AC）阴极和预锂化硬碳（HC）阳极组装而成。本文研究了两种具有不同物理和电化学性能的碳氢材料作为锂离子电池负极材料。与球形HC相比，不规则HC在充放电过程中表现出明显的锂离子嵌入平台。不规则HC嵌锂平台的存在对HC负极和AC正极的电化学行为有很大影响。通过恒流充放电、交流阻抗测试和循环性能测试，研究了工作电位范围对LIC-SH和LIC-IH电化学性能的影响。由于锂离子嵌入平台的存在，不规则HC负极的充放电电位范围低于球形HC电极，有利于AC正极的充分利用。要实现LIC电化学性能的优化，必须控制LIC的工作电位范围。LIC-IH在2.0-4.0 V工作电位范围内表现出最佳的电化学性能，能量密度高达85.7 Wh kg（1），功率密度高达7.6 kW kg（1）（以两电极活性物质质量计），5000次循环后容量保持率约为96.0%。(C)2015爱思唯尔有限公司版权所有。
Lithium-ion capacitors (LICs) are assembled with activated carbon (AC) cathode and pre-lithiated hard carbon (HC) anode. Two kinds of HC materials with different physical and electrochemical behaviors have been investigated as the negative electrodes for LIC. Compared with spherical HC, the irregular HC shows a distinct lithium ion intercalation plateau in the charge-discharge process. The existence of lithium ion intercalation plateau for irregular HC greatly affects the electrochemical behavior of HC negative electrode and AC positive electrode. The effect of working potential range on the electrochemical performance of LIC-SH and LIC-IH is investigated by the galvanostatic charging-discharging, electrochemical impedance tests and cycle performance testing. The charge-discharge potential range of the irregular HC negative electrode is lower than the spherical HC electrode due to the existence of lithium ion intercalation plateau, which is conducive to the sufficient utilization of the AC positive electrode. The working potential range of LIC should be controlled to realize the optimization of electrochemical performance of LIC. LIC-IH at the working potential range of 2.0-4.0 V exhibits the optimal electrochemical performance, high energy density up to 85.7 Wh kg (1) and power density as high as 7.6 kW kg (1) (based on active material mass of two electrodes), excellent capacity retention about 96.0% after 5000 cycles. (C) 2015 Elsevier Ltd. All rights reserved.