Effect of slurry preparation process on electrochemical performances of LiCoO2 composite electrode

Abstract The slurries comprising LiCoO 2 powder, carbon, and polymeric binder are prepared by two different mixing processes, and their rheological properties are compared. In the multi-step process, the solvent is added into solid mixture in stepwise, whereas the total amount at once in the one-step process. The former process gives the slurry that is more suitable for electrode preparation with fluid-like behavior and more uniform dispersion of solid ingredients as compared to those prepared from the letter. In the composite electrode prepared from the former, the LiCoO 2 and carbon particles are homogeneously distributed without agglomeration. Indebted to this favorable feature, this electrode exhibits a better electrochemical performance for cyclability and rate capability. It is very likely that the contact resistance and charge transfer resistance for lithiation/de-lithiation are smaller in the former electrode due to the homogeneous distribution of LiCoO 2 and carbon particles, which leads to a less significant electrode polarization.