Li/MnO_(2)一次电池用纸基隔膜的制备和性能研究

Study on Preparation and Properties of Paper-based Separator for Li/MnO_(2) Primary Battery

本研究以天丝纤维为原料,通过打浆获得原纤化天丝纤维,采用湿法成形技术制备了原纤化天丝隔膜并应用于Li/MnO_(2)一次电池,对比探讨了不同原纤化程度天丝纤维隔膜和熔喷无纺布隔膜的微观形貌、孔隙结构和电化学性能。结果表明,原纤化程度的增加使隔膜表面细小纤维覆盖主干纤维,同时孔隙率从76.3%降到67.3%,Gurley值从3.30 s增加到10.1 s,平均孔径从0.79μm降到0.35μm,电池欧姆阻抗R_(Ω)从1.55Ω增加到1.94Ω,电池放电电压平台和比容量明显降低。相比于熔喷无纺布隔膜,天丝隔膜厚度较小,平均孔径较小且孔径分布均匀,离子阻抗较低,放电性能稳定。

In this study,tencel fibers were used as raw materials to obtain fibrillated tencel fibers by pulping.By wet forming process,the separators made by fibrillated tencel fibers were applied to Li/MnO_(2) primary battery.The micromorphology,pore structure,and electrochemical properties of tencel separator with different fibrinization degrees and melt-blown non-woven fabric separator were investigated and com‐pared.The results showed that the increase of fibrinization degree made the diaphragm surface fine fibers covering the backbone fibers.With the increase of fibrinization degree,the porosity of the separator decreased from 76.3%to 67.3%,the Gurley value of the separator in‐creased from 3.30 s to 10.1 s,the average pore size of the separator decreased from 0.79μm to 0.35μm,and the ohmic impedance of the battery increased from 1.55Ωto 1.94Ω.Besides,the battery discharge voltgae platform and specific capacity were reduced significantly.Compared with melt-blown non-woven separator,tencel separator had smaller thickness,smaller average pore size and uniform pore size dis‐tribution,lower ionic impedance and stable discharge performance.