Process Flow, Installation Standards, and Daily Operation and Maintenance Manual for Complete Waste Lithium Battery Dry Stripping Production Lines

I. Overview

A complete waste lithium battery electrode dry stripping and recovery production line does not run with a single stripping host alone, but consists of six modules working together: battery safety shredding section, material buffer feeding section, core dry stripping and dissociation section, multi-stage winnowing and magnetic separation purification section, powder enclosed collection and dust removal section, and intelligent PLC total control system. As the core heart of the entire production line, the dry stripping host must be matched with upstream and downstream auxiliary machines to keep stripping efficiency, metal purity, and equipment service life stable in the long term. This article comprehensively sorts out the complete process chain, on-site installation hard specifications, and graded maintenance details to help equipment users reduce failure rates and improve electrode stripping pass rates.

II. Complete Process Flow of the Whole Dry Stripping Production Line

1. Battery Safety Shredding Pretreatment Section

After retired lithium batteries are insulated, discharged, and disassembled, the whole cells are sent to an inert-gas-protected dual-shaft shredder, which shears and crushes them into 3-5 cm regular strip electrodes in an oxygen-free environment, completely eliminating the risks of cell short circuit fire and electrolyte splash throughout. The uniform material after shredding lays the foundation for stable stripping at the back end. The shredder discharge port is equipped with an enclosed screw conveyor with no dust leakage.

2. Enclosed Buffer and Quantitative Air-Lock Feeding Section

The shredded electrodes fall into an enclosed silo, equipped with high and low level sound and light alarms to remind operators to replenish material. The variable-frequency loss-in-weight screw feeder at the bottom of the silo feeds at a uniform speed, and the rotary air-lock valve at the discharge port blocks the negative-pressure back-suction of the back-end fan, preventing material back-spray and uneven feeding, keeping the stripping host load constant and avoiding blockage and choking faults.

3. Core Dissociation Section of the Dry Stripping Host

The electrodes smoothly enter the differential-speed pressure roller group of the dry stripping machine, and the surface lithium battery active powder is stripped by extrusion, shearing, and kneading. The remaining adhered material enters the lower impact dissociation chamber for secondary beating and depowdering, completing the thorough separation of copper-aluminum metal and black mass. The operator adjusts the roller gap and speed difference through the electric control cabinet to adapt to electrode materials of different hardness and bonding strength.

4. Multi-Stage Winnowing and Magnetic Separation Deep Purification Section

The mixed material after stripping enters the gravity settling winnowing box: heavy copper foil and aluminum foil automatically fall and are collected; light black mass is taken away by negative-pressure airflow. The sorted metal material then passes through a drum magnetic separator to remove iron impurities, ensuring copper-aluminum metal purity. The lithium battery powder passes through a secondary cyclone collector, and coarse particles automatically return to the stripping host for cyclic reprocessing.

5. Dust Removal Purification and Powder Collection Section

The end of the whole system circulating air is connected to a pulse bag dust collector, capturing ultrafine floating lithium battery powder in the pipe, with clean air discharged up to standard. The collected black mass is loaded into FIBCs through an enclosed discharge valve throughout, with no manual contact and no dust flying.

6. Integrated Intelligent Electric Control System

The main control cabinet integrates the start and stop, variable-frequency speed regulation, and fault monitoring functions of the shredder, stripping host, feeder, induced fan, and magnetic separator, displaying host current, bearing temperature, and vibration values in real time. In case of over-temperature, overload, or blockage, it automatically alarms and stops, and supports connection to the plant DCS system for remote management.

III. Key On-Site Installation Specifications (Avoid 80% of Later Failures)

Equipment Foundation and Shock Absorption Fixing

The dry stripping host is placed on a thickened steel structure platform or reinforced concrete load-bearing foundation, leveled with a level and foundation bolts tightened. The induced fan and shredder are separately equipped with shock-absorbing pads to reduce vibration transmission during operation, protecting the main shaft bearing and roller seal, greatly reducing bearing wear probability. A maintenance space of ≥1 meter is reserved on the hydraulic open-cover side of the host for later chamber cleaning.

Pipeline Sealing and Anti-Blocking Design

All powder conveying pipe flanges are equipped with high-temperature-resistant rubber gaskets to eliminate air and powder leakage. The pneumatic conveying pipe is set with a downward slope, the elbow uses a thickened wear-resistant elbow, and a purge and cleaning interface is reserved at the lowest point of the pipe for regular compressed air to clean powder deposits and prevent lithium battery black mass from moisture caking and blocking the air duct.

Electrical Explosion-Proof and Anti-Static Specifications

Lithium battery powder is a flammable and explosive dust. Explosion-proof workshops must use explosion-proof motors, explosion-proof electrical boxes, and flame-retardant cables. All metal pipes and equipment bodies are reliably grounded to eliminate static accumulation. Spark detection and temperature sensors are independently wired, away from power strong-current lines, to avoid signal interference and false alarms.

The Fan Air Volume System Must Not Be Privately Modified

The fan pressure, air volume, and classification air duct are all calibrated by the manufacturer's fluid mechanics at the factory. The fan impeller and variable-frequency parameters must not be privately changed on site, otherwise it will cause sorting imbalance, black mass mixing into metal material, and dust escape.

IV. Graded Inspection and Maintenance Details of the Dry Stripping Machine

(1) Simple Inspection 5 Minutes Before Daily Start-Up

Check that the shredder and stripping host chambers have no foreign matter jamming and the silo has sufficient material; check all flanges, pipes, and air-lock valves for powder or air leakage; the electric control cabinet self-checks power-on, confirming temperature, vibration, and current parameters are within the normal range; jog test the motor steering and listen for abnormal noise or friction jamming in the host.

(2) Immediate Maintenance After Each Shift Stop

Start the pipeline compressed air purge system to empty residual lithium battery powder in the air duct and cyclone separator; check the pulse blowing solenoid valve of the dust collector, clean the ash hopper accumulation, and check whether the filter bag is blinded or damaged; record the shift stripping efficiency, metal discharge purity, and equipment operating current, and establish an operation ledger.

(3) Weekly Routine Maintenance Items

Open the hydraulic flip cover of the host, clean the caked powder adhered in the stripping chamber, check the wear of the roller surface and hammer head; slight wear can continue to be used by adjusting the roller gap, and replace immediately if wear exceeds the limit; add high-temperature-resistant grease to the main shaft and classification wheel bearings; tighten foundation bolts and pipe flange screws to eliminate loosening hazards during operation; test the flexibility of the air-lock discharge valve and magnetic drum, and clean internal jammed material.

(4) Monthly Deep Overhaul Maintenance

Disassemble and check the roller oil seal and end cover seal, replace aged seals to prevent dust from entering the bearing and causing seizure; calibrate the dynamic balance of the fan impeller, check the belt tightness and wear; check all filter bags of the dust collector, replace damaged filter bags, and clean the box dust; calibrate the weighing sensor of the loss-in-weight feeder to stabilize the host stripping load with accurate feeding measurement.

(5) Notes for Long-Term Shutdown and Sealing

When the factory is shut down seasonally or the equipment is shut down for a long time for major repair, the stripping chamber, all conveying pipes, and dust collector internal lithium battery powder must be emptied, the chamber interior wiped and dried, the main power turned off, and the equipment overall covered for dust and moisture protection to avoid residual powder absorbing moisture and corroding the roller body and inner chamber.

V. Core Taboo Points for Operation and Maintenance

Original factory customized wear-resistant rollers and alloy hammers must be used; non-standard accessories will cause dynamic balance imbalance, reduced stripping precision, and accelerated wear. Long-term overload operation beyond rated capacity is strictly prohibited to prevent motor overheating and burnout and main shaft deformation and fracture. The incoming cell must be fully discharged and disassembled; intact cells with voltage must never be directly put into the shredder to eliminate fire and explosion safety accidents. Operators must receive professional safety and operation training from the manufacturer and must not arbitrarily modify core variable-frequency parameters or remove safety protection interlocks.

The long-term stable operation of the waste lithium battery dry stripping production line relies on scientific complete process layout, standardized on-site installation construction, and normalized graded maintenance management. Strictly implementing the inspection and maintenance system can not only continuously ensure the electrode stripping rate and copper-aluminum metal recovery rate meet standards stably, but also minimize the frequency of wear-part replacement and reduce unplanned shutdown losses, allowing the whole dry lithium battery recovery production line to operate safely, efficiently, and at low cost continuously, escorting the enterprise's lithium battery resource recovery project.