A Novel Blending Adhesive in the Fabrication of the Composite Cathode for Lithium-Ion Batteries

Graphical Positive addition : A novel ionized oligomer that is synthesized by neutralizing acrylic-grafted epoxy resin with lithium hydroxide is introduced with PVdF as an additive to form a blending adhesive. The morphology, physical, and electrochemical properties of the composite electrodes are tested and discussed in detail. In this paper, a novel adhesive prepared by blending lithium-ion functionalized epoxy resin (ionized oligomer) with poly(vinylidenedifluoride) (PVdF) is used to fabricate the cathode electrode of LiCoO 2 . The properties of the blending adhesive are studied by Fourier transform infrared spectroscopy, differential scanning calorimeter, and thermogravimetric analysis, and the morphology and performance of the composite cathodes are characterized by using X-ray photoelectron spectroscopy (XPS), scanning and transmission electron microscopy, electrochemical impedance spectroscopy, and galvanostatic charge-discharge. With the blended ionized oligomer, the crystallinity behavior of PVdF is decreased effectively, which will be beneficial to the movement of conducting ions. An appropriate amount of ionized oligomer effectively improves the conductivity and charge-transfer capability of the cathode material. When the amount of ionized oligomer to the PVdF binder is 10 wt%, the LiCoO 2 -based composite cathode delivers the highest charge−discharge capacity (178 mAh g −1 ) and the capacity retention is up to 82.2 % after 100 cycles.