화학공학소재연구정보센터
Applied Chemistry for Engineering, Vol.28, No.5, 534-538, October, 2017
석유계 피치를 사용한 리튬전지 음극소재의 전기화학적 특성
Electrochemical Characteristics of Lithium Battery Anode Materials Using Petroleum Pitches
E-mail:
초록
본 연구에서는 PFO (pyrolyzed fuel oil)의 개질을 통해 탄소전구체(피치)를 제조한 후, 유기용매를 통한 분자량 조절을 하고 탄화하여 음극소재를 제조하였다. 리튬이차전지 음극소재의 전기화학적 특성은 석유계 피치를 사용하여 조사되었다. 사용된 세 종류의 피치는 3903, 4001, 4002이며, 각 PFO를 390 ℃ 3 h, 400 ℃ 1 h, 400 ℃ 2 h 열처리 하여 제조하였다. 제조된 헥산 불용성 피치의 물리적 특성은 XRD, TGA, GPC, SEM으로 분석되었다. 음극소재로서의 피치의 전기 화학적 특성은 충.방전, 순환전압전류, 임피던스, 속도 테스트를 통해 조사되었다. 4001 피치를 통하여 제조된 음극소재와 LiPF6 (EC : DMC = 1 : 1 vol%, VC 3 wt%)를 사용하여 제조한 반쪽 전지는 향상된 초기용량(310 mAh/g)을 보였으며, 초기 효율(82%), 2 C/0.1 C 속도특성(90%), 용량 유지율 85%의 특성을 보였다. 본 연구에서 제조된 피치는 사이클 특성과 속도특성이 향상됨을 알 수 있었다.
In this study, the molecular weight controlled pitches derived from pyrolyzed fuel oil (PFO) were prepared using solvent extraction and were carbonized. Electrochemical characteristics of lithium battery anode materials were investigated using these petroleum pitches. Three pitch samples prepared by the thermal reaction were 3903 (at 390 ℃ for 3 h), 4001 (at 400 ℃ for 1 h) and 4002 (at 400 ℃ for 2 h). The prepared hexane insoluble pitches were analysed by XRD, TGA, SEM and Gel permeation Chromatography (GPC). The electrochemical characteristics of the PFO-derived pitch as an anode material were investigated by constant current charge/discharge, cyclic voltammetry and electrochemical impedance tests. The coin cell using pitch (4001) and the electrolyte of LiPF6 in organic solvents (EC : DMC = 1 : 1 vol%, VC 3 wt%) has better initial capacity (310 mAh/g) than that of other pitch coin cells. Also, this carbon anode showd a high initial efficiency of 82%, retention rate capability at 2 C/0.1 C of 90% and cycle retention of 85%. It was found that modified pitches improved the cycling and rate capacity performance.
  1. Park JY, Jung MZ, Lee JD, Appl. Chem. Eng., 26(1), 80 (2015)
  2. Xu B, Qian D, Wang Z, Meng YS, Mater. Sci. Eng., 73, 51 (2012)
  3. Eom K, Joshi T, Bordes A, Do I, Fuller TF, J. Power Sources, 249, 118 (2014)
  4. Ko HS, Choi JE, Lee JD, Appl. Chem. Eng., 25(6), 592 (2014)
  5. Wang HQ, Yang GH, Cui LS, Li ZS, Yan ZX, Zhang XH, Huang YG, Li QY, J. Mater. Chem., 3, 21298 (2015)
  6. Wang LY, Bai X, Wu Y, Lun N, Qi YX, Bai YJ, Electrochim. Acta, 212, 155 (2016)
  7. Kim JG, Kim JH, Song BJ, Jeon YP, Lee CW, Lee YS, Im JS, Fuel, 167, 25 (2016)
  8. Cristadoro A, Kulkarni SU, Burgess WA, Cervo EG, Rader HJ, Mullen K, Bruce DA, Thies MC, Carbon, 47, 2358 (2009)
  9. Kim JG, Liu F, Lee CW, Lee YS, Im JS, Solid State Sci., 34, 38 (2014)
  10. Jo YN, Park MS, Lee EY, Kim JG, Houg KJ, Lee SI, Jeong HY, Ryu GH, Lee Z, Kim YJ, Electrochim. Acta, 146, 630 (2014)
  11. Jo YN, Lee EY, Park MS, Hong KJ, Lee SI, Jeong HY, Lee Z, Oh SM, Kim YJ, J. Korean Electrochem. Soc., 15, 207 (2012)
  12. Dahn JR, Zheng T, Liu YH, Xue JS, Science, 270(5236), 590 (1995)
  13. Kobayashi N, Inden Y, Endo M, J. Power Sources, 326, 235 (2016)
  14. Yoon S, Kim H, Oh SM, J. Power Sources, 94(1), 68 (2001)
  15. Kim KJ, Lee TS, Kim HG, Lim SH, Lee SM, Electrochim. Acta, 135, 27 (2014)
  16. Han YJ, Kim J, Yeo JS, An JC, Hong IP, Nakabayashi K, Miyawaki J, Jung JD, Yoon SH, Carbon, 94, 432 (2015)
  17. Kim JG, Kim JH, Song BJ, Lee CW, Im JS, J. Ind. Eng. Chem., 36, 293 (2016)
  18. Chung DW, Shearing PR, Brandon NP, Harris SJ, Garcia RE, J. Electrochem. Soc., 161, 422 (2014)
  19. Kim BH, Kim JH, Kim JG, Im JS, Lee CW, Kim S, J. Ind. Eng. Chem., 45, 99 (2017)