锌-空气电池隔膜的关键作用及其最新研究进展

Critical Role and Recent Development of Separator in Zinc-Air Batteries

在化石能源日益短缺、资源消耗急剧增加的背景下,开发可再生的清洁能源,如太阳能和风能,变得尤为重要。然而,这些清洁能源供应不稳定,因此需要大规模能源转换和储存装置的发展。在这方面,锌-空气电池能量密度高、安全性好、成本低、易组装、对环境友好并且金属锌储量丰富,作为能源储存与转换器件有良好的发展前景,但在应用的过程中仍存在一些问题。其中,隔膜在锌-空气电池中起着隔离正负极,防止短路的重要作用,但关于锌-空气电池隔膜及其改性的研究较少。本文简要介绍了锌-空气电池的发展,以水系碱性锌-空气电池为例,阐述了其工作原理。文中通过理解电池各个组件可能导致电池失效的机制,重点分析了隔膜性能对整体电池性能的影响。其中包括隔膜的离子选择性、离子导电性、稳定性以及保水性等因素。这些因素在锌-空气电池中起到至关重要的作用,直接影响电池的效率、寿命和稳定性。此外,本文还对锌-空气电池隔膜未来发展方向进行了展望。随着科技的进步,锌-空气电池的隔膜材料可能会进行更多的改良和创新,以提高电池的性能和稳定性。对于清洁能源的推动,锌-空气电池在能源储存和转换领域有望发挥更大的作用。

Amidst widespread consumption and the scarcity of non-renewable fossil fuels,the advancement of clean energy sources like solar and wind energy holds immense significance.Nevertheless,these clean energy sources grapple with unstable power supply,underscoring the pressing need for the enhancement of largescale energy conversion and storage devices.Zinc-air batteries,boasting high energy density,safety,affordability,ease of assembly,eco-friendliness,and abundant zinc metal resources,exhibit promising potential as energy storage and conversion solutions.Nevertheless,various challenges persist in their application,including a limited cycle life and inadequate power density.Throughout the charge and discharge cycles,factors such as the dendritic growth of the zinc negative electrode,the formation of Zn O passivation layers,electrolyte evaporation,and side reactions involving the diffusion of zincate ions to the positive electrode collectively exert influence on the performance of zinc-air batteries.The separator plays a crucial role in zinc-air batteries by isolating the positive and negative electrodes to prevent short circuits,and these aforementioned issues can be resolved through optimization of the design.Until now,the commonly employed separators in zinc-air batteries can be categorized into various types:standard porous separators,anion exchange membranes,polymer gel electrolyte membranes,and composite membranes comprising diverse polymer compositions.Among these,within the context of separator research,porous separators of the polyolefin type are generally utilized in aqueous alkaline zinc-air batteries.Nevertheless,their pronounced hydrophobic nature results in markedly diminished ion conductivity.Conversely,gel-based solid-state or semisolid-state electrolyte membranes are tailored for flexible electronic device applications.This adaptation ensures that zincair batteries uphold favorable electrochemical performance even under deformation conditions,simultaneously addressing the challenge of electrolyte volatilization to a certain degree.Fundamental attributes of the separator,such as pore size,hydrophilicity,and other properties,significantly impact the battery's lifespan and charge/discharge performance.Nevertheless,research on separators and their modifications to enhance zinc-air battery performance,along with the underlying principles,lags behind other aspects of zinc-air battery research,presenting ample room for advancement.This review offers a concise overview of zinc-air battery development,using aqueous alkaline zinc-air batteries as an example to elucidate their operational principles.The objective is to grasp the challenges leading to battery failure in different components and to particularly analyze how separator performance influences overall battery efficiency.This includes aspects such as ion selectivity,ion conductivity,stability,and water retention of the separator.The overview is divided into two main sections:(1) elucidating the fundamental structure and operational principles of the zinc-air battery,and(2) comprehensively exploring the fundamental attributes of the separator and its pivotal function within the zinc-air battery.The research progress and perspective for the development of zinc-air battery separators are also discussed and anticipated.