Journal of the Korean Electrochemical Society (전기화학회지)

The Korean Electrochemical Society (한국전기화학회)
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Study on Electrochemical Performances of PEO-based Composite Electrolyte by Contents of Oxide Solid Electrolyte

산화물계 고체전해질 함량에 따른 PEO 기반 복합전해질 전기화학 성능 연구

  • Lee, Myeong Ju (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Kim, Ju Young (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Oh, Jimin (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Kim, Ju Mi (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Kim, Kwang Man (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Lee, Young-Gi (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI)) ;
  • Shin, Dong Ok (Multidisciplinary Sensor Research Group, Electronics and Telecommunications Research Institute (ETRI))
  • 이명주 (한국전자통신연구원융복합센서연구그룹) ;
  • 김주영 (한국전자통신연구원융복합센서연구그룹) ;
  • 오지민 (한국전자통신연구원융복합센서연구그룹) ;
  • 김주미 (한국전자통신연구원융복합센서연구그룹) ;
  • 김광만 (한국전자통신연구원융복합센서연구그룹) ;
  • 이영기 (한국전자통신연구원융복합센서연구그룹) ;
  • 신동옥 (한국전자통신연구원융복합센서연구그룹)
  • Received : 2018.10.25
  • Accepted : 2018.11.07
  • Published : 2018.11.30
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Abstract

Safety issues in Li-ion battery system have been prime concerns, as demands for power supply device applicable to wearable device, electrical vehicles and energy storage system have increased. To solve safety problems, promising strategy is to replace organic liquid electrolyte with non-flammable solid electrolyte, leading to the development of all-solid-state battery. However, relative low conductivity and high resistance from rigid solid-solid interface hinder a wide application of solid electrolyte. Composite electrolytes composed of organic and inorganic parts could be alternative solution, which in turn bring about the increase of conductivity and conformal contact at physically rough interfaces. In our study, composite electrolytes were prepared by combining poly(ethylene oxide)(PEO) and $Li_7La_3Zr_2O_{12}$ (LLZO). The crystallinity, morphology and electrochemical performances were investigated with the control of LLZO contents from 0 wt% to 50 wt%. From the results, it is concluded that optimum content and uniform dispersion of LLZO in polymer matrix are significant to improve overall conductivity of composite electrolyte.

웨어러블 디바이스, 전기자동차와 에너지저장시스템에 대한 전력 수요가 증가함에 따라 리튬이온 전지에 있어서 안전성은 가장 중요한 요소가 되었다. 이러한 문제를 해결하기 위해 가연성의 유기 액체전해질이 불연성의 고체전해질로 대체된 전고체 전지를 제조하려는 연구들이 진행되고 있다. 그러나 고체전해질은 자체 이온전도도가 상대적으로 낮고 전극/전해질 계면에서 높은 저항이 발생하므로 실질적인 활용에 제약이 있었다. 이에 유무기 소재로 구성된 복합전해질은 고체전해질의 단점을 극복할 수 있는 대안으로 떠오르고 있다. 본 연구에서는 PEO 전해질과 LLZO 고체전해질을 복합화하여 전해질을 제조하였고, LLZO 고체전해질 함량에 따라 결정성, 형상 및 전기화학 성능 분석을 진행하였다. 결과로부터 PEO 전해질 내에 LLZO 고체전해질의 최적 함량 및 균일한 분포가 전체 복합전해질의 이온전도도 향상에 중요한 요소임을 확인하였다.

Keywords

JHHHB@_2018_v21n4_80_f0001.png 이미지

Fig. 1. (a) SEM image and (b) size distribution of synthesized LLZO powder.

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Fig. 3. Optical images of as-prepared pure PEO and composite electrolyte films.

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Fig. 4. Cross-sectional SEM images and EDS mapping of pure PEO and composite electrolytes.

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Fig. 5. TGA analysis of composite electrolytes.

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Fig. 7. Charge/discharge profiles of (a) pure PEO and (b) PEO-LLZO30 based LiFePO4/Li half-cell (0.2 C-rate @ 60℃). (c) Cycling performance of PEO-LLZO30 based LiFePO4 electrode(0.2 C-rate @ 60℃).

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Fig. 6. Nyquist plots of pure PEO and composite electrolytes.

JHHHB@_2018_v21n4_80_f0007.png 이미지

Fig. 2. XRD patterns of pure PEO, LLZO and composite electrolyte.

References

  1. P. G. Balakrishnan, R. Ramesh and T. Prem Kumar, 'Safety mechanisms in lithium-ion batteries' J. Power Sources, 155, 401-414 (2006). https://doi.org/10.1016/j.jpowsour.2005.12.002
  2. E.-H. Kil et al., 'Imprintable, bendable, and shapeconformable polymer electrolytes for versatile-shaped lithium-ion batteries' Adv. Mater., 25, 13-29 (2013). https://doi.org/10.1002/adma.201203567
  3. P. G. Bruce, S. A. Freunberger, L. J. Hardwick and J.-M. Tarascon, '$Li-O_2$ and Li-S batteries with high energy storage' Nat. Mater., 11, 20-29 (2011).
  4. F. Mizuno, A. Hayashi, K. Tadanaga and M. Tatsumisago, 'New, highly ion-conductive crystals precipitated from $Li_2S-P_2S_5$ glasses' Adv. Mater., 17, 91-921 (2005). https://doi.org/10.1002/adma.200306402
  5. A. Hayashi, S. Hama, T. Minami and M. Tatsumisago, 'Formation of superionic crystals from mechanically milled $Li_2S-P_2S_5$ glasses' Electrochem. Commun., 5, 111-114 (2003). https://doi.org/10.1016/S1388-2481(02)00555-6
  6. Y. Seino, T. Ota, K. Takada, A. Hayashi and M. Tatsumisago, 'A sulphide lithium super ion conductor is superior to liquid ion conductors for use in rechargeable batteries' Energy Environ. Sci., 7, 627-631 (2014). https://doi.org/10.1039/C3EE41655K
  7. A. Hayashi, K. Minami, S. Ujiie and M. Tatsumisago, 'Preparation and ionic conductivity of $Li_7P_3S_{11}-z$ glassceramic electrolytes' J. Non-Cryst. Solids, 356, 2670-2673 (2010). https://doi.org/10.1016/j.jnoncrysol.2010.04.048
  8. R. Kanno and M. Murayama, 'Lithium ionic conductor thio-LISICON: The $Li_2S\,GeS_2\,P_2S_5$ system' J. Electrochem. Soc., 148, A742-A746 (2001). https://doi.org/10.1149/1.1379028
  9. N. Kamaya et al., 'A lithium superionic conductor' Nat. Mater., 10, 682-686 (2011). https://doi.org/10.1038/nmat3066
  10. Y. Mo, S. P. Ong and G. Ceder, 'First principles study of the $Li_{10}GeP_2S_{12}$ lithium super ionic conductor material' Chem. Mater., 24, 15-17 (2012). https://doi.org/10.1021/cm203303y
  11. K. Takada, 'Progress and prospective of solid-state lithium batteries' Acta Mater., 61, 759-770 (2013). https://doi.org/10.1016/j.actamat.2012.10.034
  12. P. Birke, S. Scharner, R. A. Huggins and W. Weppner, 'Electrolytic stability limit and rapid lithium insertion in the fast-ion-conducting $Li_{0.29}La_{0.57}TiO_3$ perovskitetype compound' J. Electrochem. Soc., 144, L167- L169 (1997). https://doi.org/10.1149/1.1837713
  13. S. Stramare, V. Thangadurai and W. Weppner, 'Lithium Lanthanum Titanates: A review' Chem. Mater., 15, 3974-3990 (2003). https://doi.org/10.1021/cm0300516
  14. H. Nakano, K. Dokko, M. Hara, Y. Isshiki and K. Kanamura, 'Three-dimensionally ordered composite electrode between $LiMn_2O_4$ and $Li_{1.5}Al_{0.5}Ti_{1.5}(PO_4)_3$' Ionics, 14, 173-177 (2008). https://doi.org/10.1007/s11581-007-0180-1
  15. R. Murugan, V. Thangadurai and W. Weppner, 'Fast lithium ion conduction in garnet-type $Li_7La_3Zr_2O_{12}$' Angew. Chem. Int. Ed., 46, 7778-7781 (2007). https://doi.org/10.1002/anie.200701144
  16. F. Croce, G. B. Appetecchi, L. Persi and B. Scrosati, 'Nanocomposite polymer electrolytes for lithium batteries' Nature, 394, 456-458 (1988).
  17. S. Liu, N. Imanishi, T. Zhang, A. Hirano, Y. Takeda, O. Yamamoto and J. Yang, 'Effect of nano-silica filler in polymer electrolyte on Li dendrite formation in Li/ poly(ethylene oxide)-$Li(CF_3SO_2)_2N/Li$' J. Power Sources, 195, 6847-6853 (2010). https://doi.org/10.1016/j.jpowsour.2010.04.027
  18. W. Liu, N. Liu, J. Sun, P.-C. Hsu, Y. Li, H.-W. Lee and Y. Cui, 'Ionic conductivity enhancement of polymer electrolytes with ceramic nanowire fillers' Nano Lett., 15, 2740-2745 (2015). https://doi.org/10.1021/acs.nanolett.5b00600
  19. H. Zhai, P. Xu, M. Ning, Q. Cheng, J. Mandal and Y. Yang, 'A flexible solid composite electrolyte with vertically aligned and connected ion-conducting nanoparticles for lithium batteries' Nano Lett., 17, 3182- 3187 (2017). https://doi.org/10.1021/acs.nanolett.7b00715
  20. J. Zheng, M. Tang and Y.-Y. Hu, 'Lithium ion pathway within $Li_7La_3Zr_2O_{12}$-polyethylene oxide composite electrolytes' Angew. Chem. Int. Ed., 55, 12538-12542 (2016). https://doi.org/10.1002/anie.201607539
  21. J. L. Allen, J. Wolfenstine, E. Rangasamy and J. Sakamoto, 'Effect of substitution (Ta, Al, Ga) on the conductivity of $Li_7La_3Zr_2O_{12}$' J. Power Sources, 206, 315-319 (2012). https://doi.org/10.1016/j.jpowsour.2012.01.131
  22. D. O. Shin, K. Oh, K. M. Kim, K.-Y. Park, B. Lee, Y.- G. Lee and K. Kang, 'Synergistic multi-doping effects on the $Li_7La_3Zr_2O_{12}$ solid electrolyte for fast lithium ion conduction' Sic. Rep., 18053 (2015).
  23. R. Murugan, V. Thangadurai, and W. Weppner, 'Fast lithium ion conduction in garnet-type $Li_7La_3Zr_2O_{12}$ ' Angew. Chem. Int. Ed., 46, 7778-7781 (2007). https://doi.org/10.1002/anie.200701144
  24. S. H.-S. Cheng, K.-Q. He, Y. Liu, J.-W. Zha, M. Kamruzzaman, R. L.-W. Ma, Z.-M. Dang, R. K. Y. Li and C. Y. Chung, 'Electrochemical performance of allsolid- state lithium batteries using inorganic lithium garnets particulate reinforced $PEO/LiClO_4$ electrolyte' Electrochim. Acta, 253, 430-438 (2017). https://doi.org/10.1016/j.electacta.2017.08.162
  25. J.-H. Choi, C.-H. Lee, J.-H. Yu, C.-H. Doh and S.-M. Lee, 'Enhancement of ionic conductivity of composite membranes for all-solid-state lithium rechargeable batteries incorporating tetragonal $Li_7La_3Zr_2O_{12}$ into a polyethylene oxide matrix' J. Powere Sources, 274, 458- 463 (2015). https://doi.org/10.1016/j.jpowsour.2014.10.078