30 mm Twin Screw Laboratory Screw Elements for Battery Slurry Mixing Applications

The customer uses a 30 mm twin screw laboratory extruder for lithium battery electrode slurry development, focusing on small-scale formulation testing and process validation.

The key requirements include:

• Unstable dispersion behavior in battery slurry testing
• Rapid wear of screw elements under high shear conditions
• Poor repeatability between different experimental batches

The goal was to develop a screw element system suitable for laboratory-scale extrusion that improves process stability and experimental repeatability.

Battery slurry contains conductive carbon, active materials, and binder systems. Under high shear conditions, these particles continuously impact the screw surface, leading to accelerated wear.

Although this is a 30 mm laboratory extruder, the operating conditions simulate industrial environments:

• High rotational speed
• Continuous experimental operation
• Frequent material changeovers

This requires higher consistency of screw performance.

Conventional screw elements may experience:

• Geometric wear over time
• Reduced shear efficiency
• Fluctuating dispersion performance

resulting in inconsistent experimental results.

The screw system was reconfigured based on the 30 mm laboratory extruder structure:

• Optimized conveying sections
• Reinforced mixing zones
• Redefined dispersion areas

This improves functional separation across different process sections.

A specially developed alloy material system was applied, focusing on:

• Enhanced abrasion resistance
• Improved corrosion resistance
• Structural stability under continuous operation

This ensures reliable performance under battery slurry processing conditions.

Manufacturing processes include:

• CNC precision machining
• Heat treatment control
• Secondary dimensional correction

• Coordinate Measuring Machine (CMM)
• Diameter and length verification
• Spline fit inspection

• Chemical composition analysis
• Hardness testing
• Microstructure evaluation

• Laboratory extruder assembly test
• Rotation stability check
• Meshing condition verification

During battery slurry mixing tests, the screw system demonstrated:

• More stable dispersion behavior
• Improved experimental repeatability
• Controlled wear behavior
• Better batch-to-batch consistency

Overall process variability was significantly reduced, making the system suitable for formulation development and process validation.

This project addresses key challenges in 30 mm laboratory twin screw extruders used for battery slurry processing, including dispersion instability, rapid wear, and poor repeatability.

Through optimized screw design, special alloy materials, and precision manufacturing control, the system achieved improved process stability and controlled wear performance.

This solution is suitable for laboratory and pilot-scale lithium battery material development.

Battery slurry contains conductive carbon, active particles, and binder systems. Under high shear conditions, these materials cause continuous abrasive wear and require high consistency in dispersion and repeatability.

Main reasons include:

• Severe abrasive particle wear
• Long-term high shear operation
• Insufficient wear resistance
• Degradation of mixing efficiency over time

These factors reduce experimental consistency.

In this case, special alloy materials improve:

• Abrasion resistance
• Structural stability
• Long-term operational consistency
• Reduction in data variation

Laboratory screw systems focus on:

• Process repeatability
• Material testing accuracy
• Flexible formulation switching
• Small-scale validation

Industrial systems focus more on continuous production capacity.

Key factors include:

• Consistent screw geometry
• Stable wear-resistant materials
• High machining accuracy (CNC + CMM inspection)

Wear can lead to:

• Reduced shear efficiency
• Unstable dispersion performance
• Batch-to-batch variation
• Loss of process reproducibility