Meaning
Process parameter that defines the mass of wet slurry deposited per unit area on the current collector foil using a precision slot-die head. In battery electrode manufacturing, maintaining a uniform slot-die coating density is necessary to achieve consistent cell capacity and balanced electrochemical performance. This parameter is monitored continuously during the roll to roll coating process, and even minor variations can lead to substantial imbalances in the finished battery cell pack.
Thickness Control
Slurry flow rate and line speed must be synchronized to achieve the target electrode weight. The thickness control of the coating process uses real time beta-gauge or laser thickness sensors to measure deviation. Prompt adjustments to the pump speed prevent thin or heavy spots on the foil.
Quality Control
Electrode loading deviations can cause uneven current distribution and localized lithium plating. The quality control of the coating process prevents these defects by enforcing narrow tolerance bands for the dry coating weight. Consistent coating weight ensures uniform current density across the electrode sheet.
Process Output
Roll quality and cell yields are directly influenced by the stability of the coating deposition. The process output of the coating line determines the throughput of the entire electrode manufacturing facility. Minimizing startup waste and coating variations maximizes the utilization of raw materials.
