γ射线辐照交联原位固态化阻燃锂离子电池  

In situ solidification of flame-retardant lithium-ion batteries by γ-ray irradiation

作　　者：沈秀[1] 曾月劲 李睿洋 李佳霖 李伟[1] 张鹏[1] 赵金保[1] SHEN Xiu;ZENG Yuejing;LI Ruiyang;LI Jialin;LI Wei;ZHANG Peng;ZHAO Jinbao(Xiamen University,Xiamen 361005,Fujian,China)

机构地区：[1]厦门大学,福建厦门361005

出　　处：《储能科学与技术》2022年第6期1816-1821,共6页Energy Storage Science and Technology

摘　　要：电离辐射是一种高能辐射,其能量可以达到MeV级别,如此高的能量可以将原本稳定的分子或原子电离或激发,进而产生离子、自由电子、自由基等活性中间体引发共聚、接枝、交联等化学反应。本研究利用了强穿透性和极高能量的γ射线,辐照锂电池,使其由液态原位固化为凝胶态。探讨了相同辐照剂量的γ射线,对不同组分的前驱体溶液的固化程度、离子电导率、电化学窗口等的影响。利用静电纺丝,制备了含有聚磷酸铵阻燃剂的无纺布,将该阻燃多孔膜作为辐照前驱体溶液的基体,进一步为电池的安全性提供保障。结果显示,成功固化的凝胶电解质,其离子电导率可达2.5×10^(-4) S/cm。由拆解后锂片的扫描电镜图发现,原位固化的凝胶电解质对锂枝晶的生长具有一定的抑制作用。组装的磷酸铁锂半电池,室温0.05 C活化后0.5 C循环100圈,放电比容量保持在144.8 mAh/g,容量保持率为97.5%。采用高能γ射线原位辐照交联的固态化锂离子电池,具有不漏液、高离子电导率、阻燃、抑制锂枝晶等特点。本研究有助于推动动力锂离子电池的进一步产业化应用和发展。Ionizing radiation is a type of high-energy radiation with a maximum energy of MeV.This high energy can ionize or excite initially stable molecules or atoms,generating ions,free electrons,free radicals,and other active intermediates to initiate copolymerization,grafting,and chemical reactions such as cross-linking.In this study,a liquid lithium battery was irradiated and solidified into a gel state lithium battery in situ using a strong penetrating and extremely high energyγ-ray.The effects of the same irradiation dose ofγ-ray on the curing degree,ionic conductivity,and electrochemical window of precursor solutions with various components were discussed.A nonwoven membrane containing ammonium polyphosphate flame retardant was prepared using electrospinning,and the flame retardant porous film was used as the matrix of the irradiated precursor solution,providing additional assurance for the battery's safety.The results show that the successfully cured gel electrolyte has an ionic conductivity of 2.5×10^(-4) S/cm.The in-situ solidified gel electrolyte has a certain inhibitory effect on the growth of lithium dendrites,according to scanning electron microscope images of the disassembled lithium anode.The assembled lithium iron phosphate half-battery was activated at 0.05℃at room temperature and cycled for 100 cycles at 0.5℃,and the discharge specific capacity remains at 144.8 mAh/g,with a capacity retention rate of 97.5%.The solidified lithium-ion battery is cross-linked by high-energyγ-ray in-situ irradiation and has no leakage,high ionic conductivity,flame retardancy,and lithium dendrites inhibition.This study will aid in the advancement of industrial applications and the development of high-capacity lithium-ion batteries.

关 键 词：锂离子电池 Γ射线辐照 原位固态化 阻燃 

分 类 号：TM911[电气工程—电力电子与电力传动]