Battery Slitting Machine Precision Control & Failure FAQs（slitting, pole piece cutting, burr, blade wear）

A battery slitting machine is key front-end process equipment for lithium-ion cell manufacturing. It slits wide cathode/anode electrode mother rolls (after coating, drying and calendering) into narrow electrode strips of specified width, to match the dimensions required for subsequent winding or stacking procedures. Slitting quality directly impacts internal resistance, safety and cycle life of finished batteries.

The large electrode roll is unwound steadily under constant tension. A set of upper and bottom circular rotary knives perform shear cutting to split the wide sheet into multiple narrow strips. After slitting, the narrow electrodes are wound into individual small rolls with consistent tension for transfer to winding or stacking stations.

Poor slitting produces burrs, uneven edge dimensions, curling and edge cracks. Tiny metal burrs may pierce the separator during winding/stacking and trigger internal short circuits; inconsistent width causes misalignment during winding, leading to poor cell consistency and safety hazards.

Slitting width quantity and dimension, linear running speed, unwinding/rewinding tension, knife clearance, blade overlap amount, knife shaft pressure, edge trimming allowance and electrostatic elimination intensity. Different recipes are stored for cathode, anode and various electrode specifications.

Cathode (aluminum foil substrate) is harder, requiring stricter knife clearance control to avoid burrs; Anode (copper foil substrate) is softer and prone to wrinkling, demanding more stable tension and lower cutting speed. Anode generally needs slightly larger edge trimming to remove fragile coating edges.

1. Tangential shear slitting: Most widely used, stable cutting quality for standard electrodes

2. Crush slitting: For ultra-thin electrodes, reduces burr generation

3. Vertical shear slitting: Suitable for thick high-compaction electrodes with high hardness

Metal foil burrs, coating peeling off edges, uneven strip width, electrode curling/waviness, scratches on electrode surface, slanting cutting, rewinding deviation, static adhesion and foil wrinkling.

Dull cutting blades, excessive or insufficient knife clearance, uneven blade overlap, unstable running tension, vibration during high-speed operation, worn knife shafts and contaminated blade surfaces with electrode powder residues.

Friction during unwinding and cutting generates static electricity on electrode surfaces. Static attracts dust and electrode powder, contaminates the cutting edge, aggravates burr formation, and may even cause electrostatic breakdown hazards; ion fans and static bars are adopted to neutralize static charges continuously.

Precision closed-loop tension maintains consistent tension throughout unwinding, cutting and rewinding. Over-tension stretches and deforms the thin metal foil; insufficient tension leads to sheet wandering, slanting cuts and irregular rewinding rolls.

The two marginal areas of the wide mother roll have uneven coating and rough edges. Edge trimming cuts off these defective margins to guarantee uniform coating and smooth edges for all narrow electrode strips, greatly lowering the short-circuit risk of finished cells.

Yes. Operators adjust the quantity and position of circular knives on the knife shaft, reset tension, speed and clearance parameters via the HMI, and call pre-stored process recipes. Large width spans require repositioning the entire knife assembly.

Online CCD vision inspection modules are configured to continuously detect burr height, edge flatness and width deviation. Unqualified electrodes are marked; sampling offline microscope detection is conducted regularly to measure burr height accurately.

Clearance refers to the horizontal gap between upper and lower blades; overlap means vertical insertion depth. Too large clearance creates coarse burrs; too small clearance accelerates blade wear and causes edge coating crushing. Accurate matching ensures clean shear cutting.

EPC (Edge Position Control) tracks electrode edges in real time and automatically corrects the unwinding/rewinding deviation, ensuring neatly wound narrow electrode rolls without staggering layers, convenient for automatic feeding in subsequent winding processes.

The machine uploads production batch number, slitting width, running speed, tension data, cumulative output, CCD defect records, blade usage time and equipment alarms to MES. All electrode slitting data is bound with batch codes for full front-end traceability.

Full safety covers for rotating knife shafts, safety gratings, multiple emergency stop buttons, overload protection for rewinding shafts, tension break alarm, dust collection system for fallen electrode powder and anti-static protection.

Blade wear leading to burr surge, unstable tension causing wrinkling, EPC tracking failure resulting in winding misalignment, static elimination failure with dust adhesion, knife shaft vibration, uneven rewinding roll tightness and CCD image abnormal alarms.

Daily: Clean blades and dust box, check static bars and EPC operation, remove electrode powder residues

Weekly: Inspect blade sharpness, calibrate tension parameters, clean vision lens

Monthly: Adjust knife clearance and overlap, check knife shaft parallelism

Quarterly: Replace worn blades, overhaul transmission systems, back up process recipes

Applicable maximum electrode width, cutting quantity per pass, maximum operating speed, burr control accuracy requirement, equipped online CCD inspection, EPC & tension control precision, anti-static configuration, blade material durability, MES communication interface and adaptability for both cathode and anode.