磺酸型聚乙烯亚胺单离子导体聚合物电解质的制备及其电化学性能研究

A Novel Sulfonic Polyethyleneimine Single-Ion Conductive Polymer Electrolyte for Lithium-Ion Battery

通过胺基与双键官能团的迈克尔加成反应将2-丙烯酰胺基-2-甲基丙磺酸锂(AMPSLi)接枝到聚乙烯亚胺(PEI)链上,对PEI进行功能化改性制备磺酸型单离子导体PEI-AMPSLi,再与聚丙烯腈(PAN)通过静电纺丝制备纳米纤维膜。纳米纤维膜吸收电解液后得到单离子导体聚合物电解质,经热交联处理的聚合物电解质具有10.69 MPa的拉伸强度,其室温离子电导率为2.91 mS/cm,锂离子迁移数为0.89,电化学窗口为5.45(vs.Li/Li^(+))。在LiNi_(0.8)Co_(0.1)Mn_(0.1O2)/石墨全电池中用作聚合物电解质时,0.5 C倍率电流循环时初始放电容量为171 mA·h/g,200次循环后容量保持率为77.6%。

A novel single-ion conductive polymer salt(PEI-AMPSLi)was synthesized via a Michael addition reaction between the amino groups of polyethylenimine(PEI)and double bond of lithium 2-acrylamido-2-methylpropanesulfonic acid(AMPSLi).Then the PEI-AMPSLi and polyacrylonitrile(PAN)were blended by the electrospinning technique to obtain the nanofiber membrane of PEI-AMPSLi.The corresponding crosslinked single-ion conductive polymer electrolyte were obtained after activating the electrospun nanofiber membrane infiltrated with carbonate liquid electrolyte.The PAN/PEI-AMPSLi electrolyte exhibited a decent tensile strength of 10.69 MPa,high ionic conductivity up to 2.91 mS/cm at room-temperature and high lithium-ion transference number of 0.89.Its electrochemical stability window reached up to 5.45 V(vs.Li/Li^(+)).This single ion conductor gel polymer electrolyte(PAN/PEI-AMPSLi)was applicated in the high energy density battery of LiNi_(0.8)Co_(0.1)Mn_(0.1O2)/graphite,delivering an initial discharge capacity of 171 mA·h/g at 0.5 C with a capacity retention of 77.6%after 200 cycles.