Precise Dancer Control in Battery Cell Manufacturing

The electrode and separator films are wound on rollers and are assembled via calendering during the production of battery cells. This is a high-speed and intermittent operation that requires precise interaction between each component. This process requires the tension of the film web to be as constant as possible. A guide roller with a spring mechanism, known as a dancer, compensates for fluctuations and helps to maintain the web tension. The dancer's movement should be as smooth as possible around a central position. Continuous measurement of the dancer position provides important data about the process and the potential need for corrections or maintenance.

The dancer's movement is measured continuously and at a high resolution. The measurement is noncontact and has a high level of reliability. The strength and frequency of fluctuations, and any deviation from the average center position, is accurately recorded.

A metal pin is attached to the dancer. It acts as a damping element that moves along the PMI120-F90 inductive positioning system. The sensor detects these movements in a noncontact manner and with a high degree of precision. This accurately measures the dancer's movement within 0.1 millimeter, and outputs the current position in real time.

Technical Features

• Parameterizable measuring range 0 – 120 mm
• Switch point parameterization via IO-Link
• Versions with analog output and up to three switching outputs
• Repeat accuracy: ± 0.1 mm
• Resolution: 50 µm
• Degree of protection: IP67/IP69K

The PMI120-F90 inductive positioning system has no moving parts and is therefore wear-free. It is resistant to contamination and vibration. The device is available with IO-Link interface as an option. IO-Link communication allows for especially easy parameterization; in addition to the highly accurate measured values, data can be called up for use in integrated diagnostics and process optimization.

• Precise, continuous measurement of the dancer position
• Sensor with no moving parts for noncontact and wear-free measurement
• Resistant to vibration and contamination
• Optional IO-Link for simple parameterization and continuous diagnostics