Pei Fei, Huang Yimeng, Wu Lin, Zhou Shiyuan, Kang Qi, Lin Wenjie, Liao Yaqi, Zhang Yi, Huang Kai, Shen Yue, Yuan Lixia, Sun Shi-Gang, Li Zhen, Huang Yunhui
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
Adv Mater. 2024 Dec;36(49):e2409269. doi: 10.1002/adma.202409269. Epub 2024 Oct 24.
Utilizing solid-state polymer electrolytes (SPEs) in high-voltage Li-metal batteries is a promising strategy for achieving high energy density and safety. However, the SPEs face the challenges such as undesirable mechanical strength, low ionic conductivity and incompatible high-voltage interface. Here, a novel crosslinked poly(ether-urethane)-based SPE with a molecular cross-linked structure is fabricated to create high-throughput Li transport pathway. The amino-modified Zr-porphyrin-based metal-organic frameworks (ZrMOF) are introduced as multisite cross-linking nodes and polymer chain extenders. The abundant ether/ketonic-oxygen and Lewis acid sites in the SPE achieve high Li conductivity (5.7 × 10 S cm at 30 °C) and Li transference number (0.84). The interpenetrating cross-linked structure of SPE with robust mechanical strength results in a record cycle life of 8000 h in Li||Li symmetric cell. The high structural stability of ZrMOF and abundant electron-withdrawing urethane/ureido groups in the SPE with high oxidation potential (5.1 V) enables a discharge capacity of 182 mAh g at 0.3 C over 500 cycles in a LiNiCoMnO||Li cell. Remarkably, a high energy density of 446 Wh kg in a 1.5-Ah pouch cell is obtained with high loading cathode (≈4 mAh cm), demonstrating a great prospect of the current SPE for practical application in solid-state, high-voltage Li-metal batteries.
在高压锂金属电池中使用固态聚合物电解质（SPEs）是实现高能量密度和安全性的一种有前景的策略。然而，SPEs面临着诸如机械强度不理想、离子电导率低以及与高压界面不相容等挑战。在此，制备了一种具有分子交联结构的新型基于聚（醚 - 聚氨酯）的SPE，以创建高通量锂传输通道。引入氨基改性的基于锆卟啉的金属有机框架（ZrMOF）作为多位点交联节点和聚合物扩链剂。SPE中丰富的醚/酮基氧和路易斯酸位点实现了高锂电导率（30°C时为5.7×10 S cm）和锂迁移数（0.84）。具有强大机械强度的SPE互穿交联结构在锂||锂对称电池中实现了创纪录的8000小时循环寿命。ZrMOF的高结构稳定性以及SPE中具有高氧化电位（5.1 V）的丰富吸电子聚氨酯/脲基使锂镍钴锰氧化物||锂电池在0.3 C下500次循环中放电容量达到182 mAh g。值得注意的是，在高负载阴极（≈4 mAh cm）的1.5 Ah软包电池中获得了446 Wh kg的高能量密度，证明了当前SPE在固态高压锂金属电池实际应用中的巨大前景。
