Coating Line for Battery Separator Film

Stability without stress — designed for ultra-thin, microporous films

Separator films, especially those as thin as 6-9 µm, are highly sensitive to mechanical tension and surface contact. Our web handling architecture is engineered to eliminate stress points and ensure dimensional stability from unwinding to rewinding.

Our ultra-low tension design prevents film stretching, wrinkling, or deformation, while vacuum rollers and driven supports stabilize the web without touching the coated side — safeguarding delicate ceramic layers. Shaftless unwinders and rewinders with automated dual-direction splicing allow continuous production with precise tension control, ensuring operational uptime and consistent coating quality.

 Controlled thermal performance for high-speed ceramic coating lines 

Drying ceramic-coated separator films requires gentle yet efficient heat application, especially at high line speeds. Our systems use zoned temperature control, ensuring consistent drying of wet coatings without damaging the microporous structure. The preferred heating system of the customer can be used. 

With 4–5 customizable drying zones for each coating on top and bottom side, the system adapts to both speed and coating thickness, supporting production rates of up to 400 m/min. The Liftex™ hood system enables quick access for maintenance, reducing downtime. 

Micron-level precision, even at full-scale throughput 

Separator film performance depends on uniform coating thickness and porosity. The web guiding is optimized for full width coating without edge strips. Our coating modules use high performance micro-gravure ceramic coating systems with pressure chamber feeding that deliver tight layer control on both sides of the web at full production speed. The system ensures consistent 2 µm coating per side with clean edge hold. 

The result: a wrinkle-free, uniform separator with predictable electrochemical behavior. This precision improves line efficiency and reduces waste. 

Smarter lines that learn, adapt, and optimize in real time 

Process stability and traceability are non-negotiable in separator film manufacturing. Non-contact inline thickness measurement and surface inspection systems can be integrated to track coating quality continuously. IIoT integration is also available, providing real-time diagnostics, predictive maintenance alerts, and cloud-based remote support to keep your production lines optimized and downtime to a minimum. 

To support plant-wide efficiency, our systems can also integrate seamlessly with AMRs (Autonomous Mobile Robots) for automated roll transport and changeover, helping reduce manual handling and improving overall workflow speed and safety. 

Motorized dancers compensate dynamically for web tension fluctuations, which is essential for maintaining consistent coating layer thickness and mechanical stability, especially at varying speeds and across different roll diameters. 

Surface purity affects coating adhesion and downstream battery cell performance. Web cleaning equipment can be provided optionally in case it is needed. It uses ionized air jets or brushless systems to remove micro-particles, dust, or slurry residue from the substrate—without surface abrasion. 

High-resolution, non-contact laser or optical sensors monitor coating thickness in real-time across the full web width. Integrated into a closed-loop control system, it enables automatic correction for layer deviations—ensuring stable 2 µm ceramic coatings with sub-micron repeatability. 

Precision slitting units allow inline width control and edge trimming to specification. Automated or semi-automated splicing systems maintain web continuity during roll changes, significantly reducing material loss and downtime in high-speed production environments.

High-speed, digital marking heads apply batch IDs, quality status, or traceability data directly onto the separator film. Markings remain legible without affecting the substrate—simplifying compliance, quality assurance, and downstream cell assembly workflows. 

IIoT-based platform enables secure remote diagnostics, parameter tuning, and firmware updates. Real-time performance data and predictive analytics help reduce service response time, enable proactive maintenance, and ensure line availability across global sites.