Carbon binder domain (CBD) consisting of conductive carbon and polymeric binder in composite electrode serves as a mixed electron and ion conductor owing to its porous nature. In this sense, CBD microstructure significantly affects ion and electron transport in the composite electrode, thereby governing overall electrochemical performance of batteries. Regardless of its critical roles in establishing conductive pathways, how the CBD microstructure depends on manufacturing processes and the dimension of conductive additives remains insufficiently understood due to the lack of quantitative micro-scale characterization. Here, we systematically investigate influence of manufacturing methods (wet vs. dry process) and conductive additives' dimension (0D vs. 1D) on CBD microstructure. Through quantitative micro-scale structural analysis, we decouple key microstructural characteristics, including CBD distribution, cathode active material (CAM)-CBD contact area, and pore connectivity. As a result, even in structures exhibiting relatively uniform CBD distribution and favorable pore network, insufficient CAM-CBD interfacial contact can lead to pronounced degradation in electrochemical performance. This finding highlights the importance of micro-scale analysis in understanding the relationship between microstructure and electrochemical performance. Finally, microstructure-resolved characterizations demonstrate that CBD microstructure is a decisive factor in electrochemical performance and provides a quantitative basis for microstructural engineering of high-performance lithium-ion batteries.