摘要
为研究聚乙烯(PE)隔膜的特性与锂离子电池针刺安全性的关系,选择20μm厚的隔膜A(韩国产)、隔膜B(河北产)和隔膜C(江苏产),通过SEM、拉伸强度、透气度和热收缩等方法,进行基本的物理性能对比,发现断裂伸长率是主要差别。隔膜A、隔膜B和隔膜C的纵向(MD)伸长率分别为100.8%、161.7%和115.3%;横向(TD)伸长率分别为79.8%、123.7%和124.2%。制备的软包装锂离子电池均通过了针刺测试。分析针刺过程中的电压降及对比针刺后隔膜孔的大小可知,隔膜A、隔膜B和隔膜C制备的电池的平均电压降分别为0.673 mV、0.143 mV和0.170 mV,隔膜A制备的电池的电压降最大,且隔膜A的针刺孔较大。这表明,隔膜的断裂伸长率越大,电池的针刺安全性越好。
In order to study the relation between properties of polyethylene(PE)separator and nail penetration safety performance of Li-ion battery,basic physical properties of three kinds of 20μm separators(separator A was made in Korea,separator B was made in Hebei,separator C was made in Jiangsu)were tested by SEM,tensile strength,Gurley,thermal shrinkage methods.It was found that the elongation was the main difference.The machine direction(MD)elongations of separator A,separator B and separator C were 100.8%,161.7%and 115.3%,respectively.The transverse direction(TD)elongations were 79.8%,123.7%and 124.2%,respectively.The prepared pouch Li-ion batteries all passed the nail penetration test.The voltage drops in the process of nail penetration test were analyzed and the size of needle puncture hole after nail penetration test were compared,it could be seen that the average voltage drop of the battery prepared by separator A,separator B and separator C were 0.673 mV,0.143 mV and 0.170 mV,respectively.The voltage drop of the battery prepared by separator A was the biggest and its nail puncture hole was larger.It was showed that the greater breaking elongation of the separator,the better safety of the battery for nail penetration.
作者
袁园
张道振
彭波
许梦清
YUAN Yuan;ZHANG Dao-zhen;PENG Bo;XU Meng-qing(Wanxiang A123 Systems Asia Co.,Ltd.,Hangzhou,Zhejiang 311215,China)
出处
《电池》
CAS
北大核心
2021年第5期486-489,共4页
Battery Bimonthly
关键词
锂离子电池
隔膜
安全性
针刺
断裂伸长率
Li-ion battery
separator
safety performance
nail penetration
breaking elongation
