In lithium battery manufacturing, burr control is critical. Excessive burr on electrode sheets (cathode/anode) can cause:

• Internal short circuits

• Poor winding quality

• Separator damage

• Reduced battery lifespan

• Safety risks

Controlling burr during slitting directly improves battery performance, yield rate, and safety compliance.

Below are the most effective methods to reduce burr in lithium battery slitting.

Use High-Precision Slitting Blades

✔ Choose the Right Blade Material

Ceramic Blades (Zirconia)

• Extremely sharp edge

• Excellent wear resistance

• Low friction

• Ideal for ultra-thin aluminum & copper foil (6–12 μm)

Tungsten Carbide Blades

• Strong and impact-resistant

• Suitable for high-speed production

• More tolerant to machine vibration

 For ultra-high precision battery foil cutting, ceramic blades often produce less burr and dust.

 Improve Edge Grinding Quality

• Edge tolerance: ±0.003–0.005 mm

• Mirror-polished cutting edge

• Uniform bevel angle

• No micro-chipping

A poorly ground blade is the #1 cause of burr formation.

 Optimize Blade Clearance (Top & Bottom Knife Gap)

Improper clearance creates tearing instead of clean shearing.

Recommended:

• Gap = 5–10% of material thickness

• Fine adjustment for copper vs aluminum foil

• Regular gap calibration

Too large gap → tearing & burr
Too small gap → blade wear & overheating

 Control Blade Sharpness & Replacement Cycle

Even the best blade creates burr when worn.

Implement:

• Scheduled blade inspection

• Replace before visible burr appears

• Monitor edge radius growth

For lithium battery slitting:

• Edge radius should remain extremely small (< 2–3 μm)

Do NOT wait until cutting quality drops severely.

 Improve Machine Stability

Machine vibration directly increases burr.

Check:

• Shaft runout (should be minimal)

• Bearing condition

• Blade alignment

• Dynamic balance of circular blades

Unstable rotation causes uneven shear and foil edge tearing.

 Optimize Slitting Speed

Too high speed increases:

• Heat generation

• Foil deformation

• Dust production

• Burr formation

Find the balance between:

• Production efficiency

• Cutting quality

Test different RPM ranges for optimal performance.

 Maintain Proper Tension Control

Incorrect foil tension leads to:

• Wrinkling

• Stretching

• Edge distortion

• Secondary burr formation

Maintain:

• Stable unwind tension

• Even rewinding pressure

• Precise tension monitoring system

 Reduce Dust & Particle Accumulation

Metal dust can worsen burr problems.

Implement:

• Air knife cleaning

• Vacuum dust removal

• Clean blade surfaces regularly

Clean production = stable slitting performance.

 Use the Right Bevel Design

Common edge types:

• Single bevel

• Double bevel

• Compound bevel

For lithium battery foil:

• Fine single-bevel or optimized compound bevel reduces burr

• Edge angle must match foil hardness

Improper bevel angle causes material extrusion instead of shearing.

 Monitor Material Quality

Poor foil quality causes burr regardless of blade quality.

Check:

• Foil thickness uniformity

• Coating adhesion

• Surface defects

• Hardness consistency

Even perfect blades cannot fix unstable raw material.

 Quick Summary: Burr Reduction Checklist

 Final Recommendation

For lithium battery electrode slitting, the best results typically come from:

✔ High-precision ceramic circular blades
✔ Tight clearance control
✔ Stable machine alignment
✔ Strict blade replacement cycle

Reducing burr is not about one factor — it’s about system optimization.