Li Juan, Jin Qi, Yin Fei, Zhu Chuncheng, Zhang Xitian, Zhang Zhiguo
Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University Harbin 150025 People's Republic of China
Condensed Mater Science and Technology Institute, Department of Physics, Harbin Institute of Technology Harbin 150001 People's Republic of China.
RSC Adv. 2020 Nov 4;10(66):40276-40283. doi: 10.1039/d0ra06380k. eCollection 2020 Nov 2.
Lithium-sulfur (Li-S) batteries have attracted much attention due to their high theoretical energy density, environmental friendliness, and low cost. However, the practical application of Li-S batteries is impeded by a severe shuttle effect. Using polar and conductive materials to prepare a modified separator as the second collector is an effective strategy to solve the shuttle effect. Herein, a TiCT -PEDOT:PSS hybrid for modifying PP separators is successfully fabricated. In this hybrid, PEDOT:PSS can effectively prevent TiCT nanosheets from restacking and enhance the electrical conductivity of Li-S batteries, thereby promoting fast Li/electron transport and improving the sulfur utilization. Meanwhile, the introduction of TiCT -PEDOT:PSS makes TiCT nanosheets effectively anchor polysulfide, thus inhibiting the shuttle effect. As a result, Li-S cells with TiCT -PEDOT:PSS modified-separators exhibit superior performances, including a high discharge capacity of 1241.4 mA h g at 0.2C, a long cycling stability, and a low decay rate of 0.030% per cycle at 0.5C for 1000 cycles.
锂硫（Li-S）电池因其高理论能量密度、环境友好性和低成本而备受关注。然而，锂硫电池的实际应用受到严重的穿梭效应的阻碍。使用极性和导电材料制备改性隔膜作为第二集流体是解决穿梭效应的有效策略。在此，成功制备了一种用于改性聚丙烯隔膜的TiCT -聚（3,4-乙撑二氧噻吩）：聚苯乙烯磺酸盐（PEDOT:PSS）复合材料。在这种复合材料中，PEDOT:PSS可以有效防止TiCT纳米片重新堆叠，并提高锂硫电池的电导率，从而促进锂/电子的快速传输并提高硫的利用率。同时，TiCT -PEDOT:PSS的引入使TiCT纳米片能够有效锚定多硫化物，从而抑制穿梭效应。结果，采用TiCT -PEDOT:PSS改性隔膜的锂硫电池表现出优异的性能，包括在0.2C时具有1241.4 mA h g的高放电容量、长循环稳定性以及在0.5C下循环1000次时每循环0.030%的低衰减率。
