On July 1, 2026, GB 38031-2025, known as the “strictest battery safety mandate in history,” officially took effect. The thermal runaway propagation test has been upgraded from a “5-minute escape” requirement to “no fire, no explosion for 2 hours,” raising the bar for power battery safety standards once again.

High safety relies not only on materials and design but also critically on consistency control throughout the manufacturing process. For a roll of electrode, from coating to calendering and slitting, the minute deviations generated at each process step are progressively magnified and ultimately impact the safety of the entire pack. As a result, inline measurement is becoming a key enabler for extending quality control to the front end of manufacturing.

Inline Inspection Solutions for Two Critical Processes: Coating and Calendering/Slitting

Electrode manufacturing is the source of power battery consistency. Coating defines the shape, while calendering and slitting finalize it—these two sequential processes together determine the ultimate quality of the electrode.

Coating: From “Spot Inspection” to “Full-Process Monitoring”

With the continuous advancement of high-speed coating, wide-format electrodes, and high areal density batteries, traditional spot inspection methods can no longer meet the demands of high-consistency manufacturing in terms of inspection coverage, substrate fluctuation, and the ability to identify micro-defects such as missing foil.

Coating Process Applications

① ② ④ Areal Density Measurement(Positive/Negative Electrode Substrate, A/B-Side Dry & Wet Coating)

③ ⑤ Edge Thickness Measurement(Integrated Areal Density Gauge & Laser/X-ray Thickness Gauge)

⑥ ⑦ CCD Dimensional Inspection(A/B-Side Dry & Wet Coating Dimensions, Coating Edge Alignment)

⑧ CCD Surface Defect Inspection(A/B Side)

To address these challenges, MANST has built an inline measurement solution covering key inspection points including wet/dry film areal density, dry film thickness, simultaneous A/B side inspection, edge inspection, and CCD visual inspection, enabling full-process quality monitoring of the coating operation.

Among these, the 100% full-inspection areal density gauge achieves complete full-area coverage. Through multi-station synchronous measurement, it simultaneously monitors wet/dry film areal density and substrate thickness with a synchronization accuracy of ±2 mm, accurately outputting the net coating areal density and effectively eliminating measurement errors caused by substrate fluctuation.

Furthermore, based on multi-parameter correlation analysis, the system feeds inspection data back to the slot-die control system in real time, realizing an intelligent closed loop of “real-time inspection—deviation analysis—real-time adjustment” and transforming process adjustments from experience-driven to data-driven.

Calendering and Slitting: From “Quality Verification” to “Closed-Loop Control”

After drying, calendering, winding/unwinding, and slitting, the electrode’s thickness, dimensions, and edge condition may still change; therefore, the calendering and slitting process bears the important responsibility of final quality verification.

Calendering & Slitting Process Applications

① Laser/X-ray Inspection System(Electrode Thickness, Areal Density & Edge Thinning after Calendering)

② ③ CCD Vision Inspection(Positive/Negative Electrode Surface Defects & Slitting Dimensions)

As electrode thickness control enters the micron-level era, traditional inspection methods can no longer satisfy the requirements of high-speed, wide-format production lines. To address issues such as thickness variation, roller deformation, slitting burrs, and dimensional deviations, MANST employs laser/radiation inline thickness measurement systems and CCD visual inspection systems to achieve simultaneous online inspection of thickness, dimensions, and appearance defects.

The laser inline thickness gauge offers a measurement accuracy of ±0.3 μm and a minimum resolution of 0.01 μm. Real-time thickness data feedback forms a closed-loop control that automatically adjusts roll gap, rolling force, and bending cylinder pressure. Meanwhile, the CCD vision system simultaneously performs edge position, slitting dimension, and surface defect inspection, and automatically carries out dimensional correction, providing stable and reliable electrode quality assurance for subsequent processes such as winding and stacking.

From Single-Point Inspection to a Full-Process Closed-Loop Control System

Centered on the two critical processes of coating and calendering/slitting, MANST has achieved interconnectivity of inspection data. The system uses CCD visual inspection to perform online detection of edge position, coating boundary, surface defects, and slitting dimensions, and automatically completes dimensional deviation analysis and correction control. The NG tag linkage function can mark abnormal products in real time, providing a reliable basis for subsequent precise rejection and quality traceability.

At the same time, all inspection data can be connected to the MES, enabling integrated management of inspection data, process parameters, and production information. It supports full-process quality traceability, statistical analysis such as CPK and MAX/MIN, and continuous process optimization, while integrating data analysis and measurement system analysis (MSA) tools. This provides a solid data foundation for AI-based quality inspection and smart factory construction.

From monitoring coating quality at the source to verifying electrode quality at the end, inline measurement upgrades quality management from “post-process inspection” to “in-process control,” driving power battery manufacturing toward greater stability, efficiency, and traceability.

Empowering High-Quality Manufacturing with Full-Process Quality Measurement

MANST’s inline measurement solutions are already stably deployed in multiple leading domestic power battery manufacturers, covering critical manufacturing steps such as high-speed coating and calendering/slitting (calendering and slitting), and delivering full-process quality assurance for the production of high-energy-density, fast-charging, and energy storage batteries.

From “post-process inspection” to “full-process controllability,” inline measurement is reshaping the quality control paradigm for power batteries. With its one-stop measurement solution covering the entire coating and calendering/slitting processes, MANST is building a solid first line of defense for battery safety at the manufacturing stage.

Looking ahead, MANST will continue to focus on the critical processes of electrode manufacturing. Through its one-stop inline measurement solution that spans the entire process, the company helps customers build a more stable, efficient, and traceable quality management system, providing reliable support for the high-quality development of power batteries.