Zhang Xiang, You Zijian, Cui Yuming, Lv Zhiqiang, Xu Yanbin, Yang Zhenglong
School of Materials Science and Engineering, Ludong University, Yantai 264025, China.
School of Energy Power and Electrical Engineering, Ludong University, Yantai 264025, China.
Langmuir. 2025 Sep 16;41(36):24833-24840. doi: 10.1021/acs.langmuir.5c03346. Epub 2025 Sep 4.
Increasing the mass loading of active materials offers significant potential for enhancing the energy density of flexible lithium-ion batteries on the system scale. However, this approach is hindered by the impeded Li diffusion kinetics and insufficient mechanical flexibility. To address this, we developed a tricontinuous sponge-like LiFePO-based flexible cathode using an ethanol-induced phase separation technique. The continuous sponge-like micromesopores enhance electrolyte permeation and shorten the Li diffusion pathway and resistance while a continuous dual-scale electron-transporting network ensures excellent electron transport. Besides, a continuous PVDF-HFP network forms an integrated flexible porous electrode skeleton. This synergistic tricontinuous network simultaneously boosts charge transport efficiency and mechanical resilience, even under ultrahigh mass loading. Consequently, the cathode achieves a favorable mass loading of 14 mg cm, delivering exceptional rate performances (159.85 mAh g at 0.2C and 120.14 mAh g at 2C) and cycling stability (79.93% capacity retention after 140 cycles at 1C). Remarkably, at an ultrahigh mass loading of 114 mg cm, it attains a record areal capacity of 13.69 mAh cm. This study offers a promising strategy for optimizing ultrahigh-mass-loading flexible electrodes, paving the way for advanced flexible lithium-ion batteries to practical applications.
在系统层面上，增加活性材料的质量负载量为提高柔性锂离子电池的能量密度提供了巨大潜力。然而，这种方法受到锂扩散动力学受阻和机械柔韧性不足的阻碍。为了解决这个问题，我们使用乙醇诱导相分离技术开发了一种基于磷酸铁锂的三连续海绵状柔性阴极。连续的海绵状微介孔增强了电解质的渗透，缩短了锂的扩散路径和电阻，同时连续的双尺度电子传输网络确保了优异的电子传输。此外，连续的聚偏氟乙烯-六氟丙烯网络形成了一个集成的柔性多孔电极骨架。这种协同的三连续网络即使在超高质量负载下也能同时提高电荷传输效率和机械弹性。因此，该阴极实现了14 mg cm的良好质量负载，展现出优异的倍率性能（0.2C时为159.85 mAh g，2C时为120.14 mAh g）和循环稳定性（1C下140次循环后容量保持率为79.93%）。值得注意的是，在114 mg cm的超高质量负载下，它实现了13.69 mAh cm的创纪录面积容量。这项研究为优化超高质量负载柔性电极提供了一种有前景的策略，为先进的柔性锂离子电池走向实际应用铺平了道路。
