Combination of 3D current collectors and in situ polymerized electrolytes enabling high-mass-loading cathodes for solid-state lithium batteries
Combination of 3D current collectors and in situ polymerized electrolytes enabling high-mass-loading cathodes for solid-state lithium batteries
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DOI：
10.1063/5.0147529
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发表时间：
2023-05
影响因子：
4
通讯作者：
Qi-Chang Sun;M. Tufail;Wenkai Li;N. Zhao;Z. Bi;Xiangxin Guo
中科院分区：
文献类型：
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作者：
Qi-Chang Sun;M. Tufail;Wenkai Li;N. Zhao;Z. Bi;Xiangxin Guo
固态锂电池具有较高的理论能量密度和较高的安全性，是未来很有发展前景的储能设备。然而，SSLBS的实际能量密度受到阴极材料的有限质量负载的严重制约，这与厚阴极内部电荷转移的迟缓有关。在本工作中，通过引入三维电导集电器和聚合物电解液的原位固化，实现了高质量负极的固态电池。3D碳毡的多孔式电子集电体可容纳流动的阴极浆料，极大地增加了阴极材料的负载。随后，原位固化的聚合物电解质确保了阴极内的共形离子传导通道，并在阴极/电解液界面形成了紧密而灵活的接触。采用这种方法制备的LiFePO4/石榴石/Li电池正极容量为159.4 mg cm−2，在30°C和0.1C下循环100次后，首次放电容量为159.4 mAHg−1，容量保持率为92.1%，负极质量负载量高达27.8 mg cm−2，面积容量约为4.2mAhcm−2。
Solid-state lithium batteries (SSLBs) are promising energy storage devices in the future due to their high theoretical energy density and enhanced safety. However, the practical energy density of SSLBs is severely constrained by the limited mass loading of cathode materials, which is related to sluggish charge transfer inside the thick cathodes. In this work, the solid-state batteries with high-mass-loading cathodes are realized by introduction of three-dimensional (3D) electronic-conductivity current collectors and in situ solidification of polymer electrolytes. The porous electronic current collectors of 3D carbon felts accommodate the flowing cathode slurry with considerably increased loading of cathode materials. Subsequently, the in situ solidified polymer electrolytes ensure conformal ionic conducting channels inside the cathodes, along with the formation of intimate and flexible contacts at cathode/electrolyte interfaces. In this way, the solid-state LiFePO4/garnet/Li batteries with cathode loading of 6.2 mg cm−2 show an initial discharge capacity of 159.4 mAh g−1 and a capacity retention of 92.1% after 100 cycles at 30 °C and 0.1 C. Furthermore, the cathode mass loading as high as 27.8 mg cm−2 is achieved with a corresponding areal capacity of approximately 4.2 mAh cm−2. This work proposes a promising unique cathode architecture for solid-state lithium batteries with high mass loading of the cathode.