Improvement of Lithium‐Ion Battery Performance by Two‐Layered Slot–Die Coating Operation

Abstract

The cathode and anode electrodes in lithium‐ion batteries typically contain a significant proportion of particles and binders. During the electrode drying process, high temperature will lead to the binder migration phenomenon. Uneven particle/binder distribution can cause poor adhesion between coating and substrate, disruption of conductive paths, and decrease in electrode performance. In this study, a two‐layered cathode was designed by using separate compositions of slurry ingredients in each layer, as produced by means of a simultaneous multilayer coating method. The two‐layered cathode with the top layer containing less binder than the bottom layer yielded a better particle/binder distribution in the final structure under high‐temperature drying. A battery made with the two‐layered cathode appeared to give a better overall performance.

High‐Speed Coating of Primer Layer for Li‐Ion Battery Electrodes by Using Slot‐Die Coating

“…[1][2][3][4][5][6] To handle the insufficient adhesion problem at low binder content, some approaches use multilayer electrodes with binder and additive gradients. [7][8][9][10] One approach, which is used in this work, is to apply a very thin primer layer to the current collector to significantly improve the adhesive force in combination with a low binder content in the active layer (see Figure 1). Several works have already addressed the properties of primers in battery electrodes.…”

Three‐dimensional simulation of transport processes within blended electrodes on the particle scale

“…These slurries are in the following to be fed to the coating unit according to the desired stratification. An example for this approach can be found in experimental studies of Liu et al, who used a simultaneous slot‐die coating process to fabricate electrodes consisting of two layers containing different kinds of conductive additives, namely graphite and carbon black.…”

Analysis of microstructural effects in multi-layer lithium-ion battery cathodes

“…In future work, it would be interesting to focus on the spatial distribution of these additives, which are not visible using the tomographic imaging procedure described in the present paper. E.g., in [40], the usage of multi-layer electrodes with a different amount of binder in the slurry for the top layer than for the bottom layer resulted in a preferable binder distribution in the overall electrode.…”