Battaglia Alicia M, Pahlavanlu Paniz, Grignon Eloi, An So Young, Seferos Dwight S
Department of Chemistry, University of Toronto, 80 Street George Street, Toronto, Ontario M5S 3H6, Canada.
Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada.
ACS Appl Mater Interfaces. 2022 Sep 21;14(37):42298-42307. doi: 10.1021/acsami.2c10070. Epub 2022 Sep 9.
Organic electrodes are promising candidates for next-generation lithium-ion batteries due to their low cost and sustainable nature; however, they often suffer from very low conductivity and active material loadings. The conventional binder used in organic-based Li-ion batteries is poly(vinylidene fluoride) (PVDF), yet it is electrochemically inactive and thus occupies volume and mass without storing energy. Here, we report an organic mixed ionic-electronic conducting polymer, poly[norbornene-1,2-bis(C(O)OPEDOT)]--[norbornene-1,2-bis-(C(O)PEG)] denoted PEDOT--PEG for simplicity, as a cathode binder to address the aforementioned issues. The polymer contains a poly(3,4-ethylenedioxythiophene) (PEDOT) functionality to provide electronic conductivity, as well as poly(ethylene glycol) (PEG) chains to impart ionic conductivity to the cathode composite. We compare electrodes containing a perylene diimide (PDI) active material, conductive carbon, and a polymeric binder (either PVDF or PEDOT--PEG) with different weight ratios to study the impact of active material loading and type of binder on the performance of the cell. The lithium-ion cells prepared with the PEDOT--PEG polymer binder result in higher capacities and decreased impedance at all active material loadings compared to cathodes prepared with the PVDF-containing electrodes, demonstrating potential as a new binder to achieve higher active material loadings in organic electrodes. The strategy of preparing these polymers should be broadly applicable to other classes of mixed polymer conductors.
有机电极因其低成本和可持续性，是下一代锂离子电池很有前景的候选材料；然而，它们常常存在电导率极低和活性材料负载量低的问题。用于有机基锂离子电池的传统粘结剂是聚偏二氟乙烯（PVDF），但它是电化学惰性的，因此占据体积和质量却不储存能量。在此，我们报道一种有机混合离子 - 电子导电聚合物，聚[降冰片烯 - 1,2 - 双（C(O)OPEDOT）] - - [降冰片烯 - 1,2 - 双（C(O)PEG）]，为简便起见记为PEDOT - - PEG，作为一种阴极粘结剂来解决上述问题。该聚合物含有聚（3,4 - 乙撑二氧噻吩）（PEDOT）官能团以提供电子导电性，以及聚乙二醇（PEG）链以赋予阴极复合材料离子导电性。我们比较含有苝二酰亚胺（PDI）活性材料、导电碳和具有不同重量比的聚合物粘结剂（PVDF或PEDOT - - PEG）的电极，以研究活性材料负载量和粘结剂类型对电池性能的影响。与用含PVDF电极制备的阴极相比，用PEDOT - - PEG聚合物粘结剂制备的锂离子电池在所有活性材料负载量下都具有更高的容量和更低的阻抗，证明其作为一种新型粘结剂在有机电极中实现更高活性材料负载量的潜力。制备这些聚合物的策略应广泛适用于其他类别的混合聚合物导体。
