储能科学与技术 ›› 2017, Vol. 6 ›› Issue (S1): 15-.doi: 10.12028/j.issn.2095-4239.2017.0129

• 特约文章 • 上一篇    下一篇

硬碳包覆人造石墨作为锂离子电池负极材料的快充性能评价

吴敏昌1,喻宁波1,乔永民1,孙方静2,张  洁1   

  1. 1上海杉杉科技有限公司,上海 201209;2上海第二工业大学,上海 201209
  • 收稿日期:2017-07-24 修回日期:2017-08-30 出版日期:2017-10-01 发布日期:2017-10-01
  • 通讯作者: 张洁,博士,工程师,主要研究方向为高容量锂离子电极材料及电解液的匹配,E-mail:zhang.jie@shanshantech.com。
  • 作者简介:吴敏昌(1978—),男,硕士,工程师,主要研究方向为锂离子电池的负极材料,E-mail:wu.minchang@shanshantech.com
  • 基金资助:
    上海市青年科技英才扬帆计划资助(17YF1413500)

The evaluation of fast-charging performance of hard carbon coating artificial graphite for lithium-ion batteries

WU Minchang1, YU Ningbo1, QIAO Yongmin1, SUN Fangjing2, ZHANG Jie1   

  1. 1 Shanghai Shanshan Tech. Co., Ltd, Shanghai 201209, China; 2 Shanghai Polytechnic University, Shanghai 201209, China
  • Received:2017-07-24 Revised:2017-08-30 Online:2017-10-01 Published:2017-10-01

摘要: 电动汽车及混合动力汽车的发展对锂离子电池的功率特性提出了更高的要求。目前商业化的锂离子电池负极材料以石墨为主。然而石墨材料的层间距较小(0.335 nm),锂的扩散受到限制,不利于大电流充电。因此,制备和评价具有快充能力的石墨负极材料将有力推动锂离子电池在电动汽车中的应用。本文选择了一种小粒径(约6.7 μm)人造石墨,通过包覆硬碳进一步提高材料的快充性能。采用SEM、BET等表征材料的物理指标。考察材料首次充放电曲线、倍率、电化学阻抗和锂离子扩散系数等,评价硬碳包覆对快充性能的影响。

关键词: 锂离子电池, 人造石墨, 表面包覆, 快充

Abstract:

With the development of electric vehicles (EVs) and hybrid electric vehicles (HEVs), the high-power lithium-ion battery is urgently needed. Nowadays, the commercial anode material is still mainly occupied by graphite. When charging in high-rate, the diffusion of lithium is greatly restricted because of the small interlayer distance (0.335 nm) of graphite, leading to a inferior high-rate charge performance. Therefore, the preparation and evaluation of fast-charging graphite will promote the application of lithium-ion battery in the EVs or HEVs. In this paper, a kind of artificial graphite with a diameter~6.7 μm is modified by coated with hard carbon to improve the fast-charging performances. The physical properties of uncoated and coated materials are characterized by SEM and BET. And the initial charge/discharge, rate, EIS and GITT were applied to evaluate the impact of hard carbon layer on the fast-charging performances.

Key words: lithium-ion battery, artificial graphite, surface coating, fast-charging