Luo Xiansheng, Jiao Lifang, Chao Dongliang, Li Fujun, Wang Rui, Zhang Shilin, Ma Quanwei, Li Hongbao, Zhang Longhai, Zhang Chaofeng
Institutes of Physical Science and Information Technology, School of Materials Science and Engineering, Leibniz International Joint Research Centre of Materials Sciences of Anhui Province, Anhui University, Hefei, 230601, China.
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), State Key Laboratory of Advanced Chemical Power Sources, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China.
Angew Chem Int Ed Engl. 2025 Aug 26:e202514375. doi: 10.1002/anie.202514375.
Four-electron aqueous zinc-iodine batteries (4eAZIBs) with the successful I/I/I redox couples have emerged as a promising alternative for large-scale energy storage due to their high energy density. However, the practical application of these batteries, particularly in harsh environments, is hindered by the poor reversibility of Zn plating/stripping processes and the instability of I species in conventional aqueous electrolytes. Here, we design a multi-component hybrid electrolyte composed of Zn(ClO), ZnCl, glycerol (Gly), and polyvinyl alcohol (PVA) to enable highly reversible operation of 4eAZIBs across a wide temperature range. Theoretical calculations, molecular dynamics simulations, and spectral analyses reveal that Gly and PVA synergistically modify the intrinsic hydrogen bond network and effectively reduce the content of active water molecules, thereby enhancing the plating/stripping behavior of Zn, suppressing the hydrolysis of I, and lowering the freezing point of the electrolyte. Moreover, the PVA-containing dual-salt system reduces the Gibbs free energy of the I/I/I reaction, facilitating enhanced stability of the 4eAZIBs even under low chloride concentrations. Consequently, the Zn||I full cells using this system exhibit a remarkable lifespan of 15 000 cycles with a capacity attenuation of 0.15% per hundred cycles, and along with excellent performance over a wide temperature range from -50 to 40 °C.
具有成功的I/I/I氧化还原对的四电子水系锌碘电池（4eAZIBs）因其高能量密度已成为大规模储能的一种有前景的替代方案。然而，这些电池的实际应用，特别是在恶劣环境中，受到锌镀层/剥离过程的可逆性差以及传统水系电解质中碘物种的不稳定性的阻碍。在此，我们设计了一种由Zn(ClO)、ZnCl、甘油（Gly）和聚乙烯醇（PVA）组成的多组分混合电解质，以实现4eAZIBs在宽温度范围内的高度可逆运行。理论计算、分子动力学模拟和光谱分析表明，Gly和PVA协同修饰了固有的氢键网络，并有效降低了活性水分子的含量，从而增强了锌的镀层/剥离行为，抑制了碘的水解，并降低了电解质的冰点。此外，含PVA的双盐体系降低了I/I/I反应的吉布斯自由能，即使在低氯化物浓度下也有助于提高4eAZIBs的稳定性。因此，使用该体系的Zn||I全电池表现出15000次循环的显著寿命，每百次循环的容量衰减为0.15%，并且在-50至40°C的宽温度范围内具有优异的性能。
