For high-precision slot-die coating of NMP-based cathode slurries, a precise screw pump (specifically a Progressive Cavity Pump) is often considered superior to a peristaltic pump for industrial or high-end R&D. While peristaltic pumps are easier to clean, screw pumps provide a pulseless, continuous flow that is critical for eliminating "chatter marks" (thickness ripples) on your electrodes at higher coating speeds.

A screw pump consists of a single-helix metallic rotor and a double-helix elastic stator. As the rotor turns inside the stator, it creates a series of sealed "cavities" that move from the suction side to the discharge side. (1) Volumetric Precision: The amount of slurry delivered is directly proportional to the rotation speed. (2) Pulseless Delivery: Unlike peristaltic or piston pumps, the geometry of the cavities ensures that the displaced volume is constant. This results in an incredibly smooth "coating bead" at the slot-die lip.

References:

H. Lee, et al., Design and Assembly of a Thin-Film-Based Micro Pump for a Micro-slot Die, International Journal of Precision Engineering and Manufacturing, 2020, 21, 2335–2344

X. Ding, et al., A review of the operating limits in slot die coating processes, AICHE J., 2016, 62, 2508-2524.