Prismatic Cell Insulation Film Wrapping Machine | TOB-SFCA-300

Automatic Prismatic Battery Cell Insulation Film Wrapping Machine

Product Overview and Ideal Applications

The TOB-SFCA-300 is an automatic prismatic battery cell insulation film wrapping machine that applies insulation film to finished prismatic aluminum-shell lithium-ion battery cells. The wrapping step is a critical quality and safety operation in prismatic cell production: the insulation film electrically insulates the aluminum casing, prevents short circuits if cells contact one another or a metal fixture inside a module, and provides a clean, uniform appearance that identifies the finished product.

The TOB-SFCA-300 performs the complete wrapping sequence automatically: conveyor-belt cell feeding, insulation film unwinding, loop wrapping of the cell body, folding of the top and bottom edges, and conveyor-belt unloading. The machine is designed to handle a wide range of prismatic cell sizes—cell width from 115 mm to 300 mm, cell height from 90 mm to 200 mm, and cell thickness from 25 mm to 45 mm—covering most commercial prismatic cell formats from energy-storage and EV applications down to smaller consumer formats.

The system is built on a welded square-tube frame with a profile-and-acrylic enclosure, and it integrates eight functional modules: rack and enclosure, main electrical wiring, feeding, unwinding, wrapping, loop-wrapping side folding, top and bottom folding, and unloading. A servo-controlled traverse robot loads the cell into the wrapping station, the unwinding module feeds the insulation film with automatic web guiding and tension control, the wrapping module presses the film onto the bottom and both large faces, and the folding modules complete the top and bottom edges before the finished cell is transferred to the unloading belt. Each machine is operated by one person per shift.

Ideal for:

• Prismatic aluminum-shell cell production lines that require the insulation film wrapping step to be fully automated after formation and capacity grading.
• Energy-storage and EV cell manufacturers processing large-format prismatic cells (up to 300 mm wide) where manual wrapping is physically demanding and inconsistent.
• Pilot and small-series production facilities that need a single operator per shift to manage an automatic wrapping station.
• Cell manufacturers whose quality system requires documented, repeatable wrapping quality, MES data upload for film consumption, and strict particle and scratch control on the cell surface.

Where the Insulation Film Wrapping Step Fits in Prismatic Cell Production

In the manufacturing flow for a prismatic aluminum-shell cell, film wrapping occurs after cell assembly, formation, degassing, and capacity grading, and immediately before final inspection and module assembly. The sequence is:

1. Cell assembly – Electrode stacking or winding, tab welding, insertion into the aluminum shell, electrolyte filling, and sealing.
2. Formation and grading – First charge and discharge, SEI formation, capacity measurement, and cell sorting.
3. Degassing and final sealing – Removal of formation gases and hermetic closure.
4. Insulation film wrapping (the TOB-SFCA-300's role) – Application of the insulation film to the cell body and edges.
5. Final inspection and module assembly – Visual check, OCV verification, and pack integration.

The insulation film serves two purposes. Functionally, it prevents the electrically live aluminum casing from contacting other cells or conductive parts within the module, reducing the risk of external short circuits. Commercially, it provides a consistent, professional finish and a surface on which the cell model and traceability information can be printed.

The TOB-SFCA-300 integrates into this chain as a self-contained, one-operator station. The operator loads cells onto the feeding belt, and the machine automatically conveys, wraps, folds, and unloads the finished cells. The PLC-based control system supports three operating modes—automatic, manual, and maintenance—with manual mode allowing individual operation of each moving part for setup, and maintenance mode locking the moving parts for safe servicing. The servo drivers communicate over the EtherCAT bus, providing fast response and strong anti-interference performance in the production environment.

How the Automatic Prismatic Battery Cell Insulation Film Wrapping System Operates

The TOB-SFCA-300 executes the wrapping process through a coordinated sequence of servo-driven modules, as described in the equipment specification:

1. Cell feeding: The cell is placed on the feeding belt and conveyed to the wrapping station. The feeding module includes an adjustable pull-strap design with polyurethane double-layer rubber-coated guide rollers, an anti-rear-collision sensor, and a brush-and-dust-collection box mounted under the pull strap for automatic cleaning. A servo-controlled traverse robot—designed with a flexible arm, dual sensors to prevent cell tilting, and power/gas cut-off protection—transfers the cell into the wrapping station. All parts that contact the cell are made of non-metallic materials, and the positioning blocks are chamfered to prevent scratches.

2. Insulation film unwinding: The insulation film, supplied on a roll with a release liner, is loaded onto the unwinding air shaft. The release liner and the film are separated: the film passes through a buffer roller, is corrected by the automatic web-guiding system (correction response ≤ 0.5 s, deviation ≤ ±0.5 mm), passes through a static eliminator, and reaches the film-pulling position. The release liner is rewound by a motor-and-brake winding mechanism. The unwinding shaft is designed to withstand a load of > 30 kg without bending, and the film roll diameter is ≥ 420 mm with a maximum width ≥ 330 mm. The unwinding tension is controlled by a servo mechanism and is adjustable, and a material sensor provides a low-film warning.

3. Loop wrapping: The cell is pushed into the wrapping station, guided by bottom rollers inclined at 1–2° and positioned by single-side guide wheels with a positioning accuracy of ±0.2 mm. The upper and lower pressure rollers—each driven by an independent servo motor with a positioning accuracy of 0.02 mm—press the two large faces of the cell while the film is wrapped around the bottom surface and both large faces. A film-pulling rod, servo-controlled with a positioning accuracy of ±0.2 mm, rotates 10–30° during pulling to increase the pulling area and prevent film peeling. After the wrapping is complete, the film is cut by a rodless cylinder (stroke ≥ 400 mm) with guide-rail guidance; the cutter is fitted with a safety protective cover. The top pushing block is designed to avoid the poles and the explosion-proof valve.

4. Loop wrapping side folding: The side folding module uses upper and lower folding side rollers, together with material detection and positioning mechanisms, to complete the wrap on the side edges of the cell body.

5. Top and bottom folding: The cell arrives at the bottom of the folding station and is first precisely positioned (accuracy ±0.2 mm), then pressed and fixed on all five sides—left and right, front and back, and the top surface. The pressing area exceeds 2/3 of the large-face area of the cell. The folding sequence is: first the short edges of the top and bottom are folded simultaneously, then the long edges of the top and bottom. The folding blocks are driven by cylinders with guide-rail guidance, and the stroke of the folding blocks is adjustable. During folding, the cell is held stationary with no rotational angle deviation, and no dents, scratches, or deformation are permitted.

6. Unloading: After the wrapped prismatic cell is picked up by a servo-controlled traverse mechanism, it is placed onto the unloading belt. The unloading module includes adjustable pull-strap stops, polyurethane guide rollers (diameter 20 ± 2 mm), an anti-rear-collision sensor, and a brush-and-dust-collection box for automatic cleaning. The belt for each individual cell can operate independently, and the pull-strap height is 850 ± 10 mm. A flat conveyor belt connects the unloading station to downstream equipment.

Control system features:

• Servo drivers communicate over the EtherCAT bus for fast response and strong anti-interference.
• 10 % of the host computer's I/O points are reserved for future expansion; at least 8 I/O points and one expansion-module space are reserved in the PLC.
• The PLC has at least two Ethernet ports—one for MES integration and one for central control-system integration—with remote-control functionality.
• The user interface supports three-level password access control, recipe and production-data statistics, and historical alarm-information recording.
• The system is divided into automatic, manual, and maintenance modes. Manual mode allows individual operation of each moving part; maintenance mode locks the moving parts for safety.
• The robotic arm is a flexible design with photoelectric and torque-based anti-fool-proofing. After a flexible-arm alarm is triggered, the gripper and other mechanisms do not deform or break, and power/gas cut-off mechanisms prevent the cell from falling.
• The host computer statistically analyzes material feeding/unloading capacity and waiting time, with data stored for at least one month.

Technical Specifications

Bare Cell Product Specifications

Equipment Process Flow

Overall Dimensions

Operator Configuration

Equipment Functional Modules (single unit, subject to actual design)

Key Technical Requirements of the Wrapping Modules

The following key parameters define the precision and quality of the TOB-SFCA-300's wrapping operation, as specified for each module.

Unwinding Module

Wrapping Module

Fold Top and Bottom Module

General Equipment Requirements

Major Electrical Components and Parts Brands

The following table lists the specified brands for the major components of the TOB-SFCA-300. (For delivery considerations, the supplier reserves the right to select equivalent brands of the same level according to market supply without notifying the customer.)

Equipment Supply List

Control System Specifications

Engineering FAQ

Q1: What cell formats can the TOB-SFCA-300 wrap?

The TOB-SFCA-300 is designed for prismatic aluminum-shell cells with a cell width of 115–300 mm, cell height of 90–200 mm, and cell thickness of 25–45 mm. Changeover between sizes within this range is handled through the adjustable guide-wheel width (hand-crank), the adjustable pull-strap stops, and the recipe system on the touch-screen HMI. Tooling adjustments for a specific cell model are performed in manual mode.

Q2: How does the machine ensure that the insulation film does not peel or wrinkle during wrapping?

Three design features address film quality. First, the unwinding module maintains a servo-controlled, adjustable tension on the film and corrects web deviation to ≤ ±0.5 mm with a response time of ≤ 0.5 s, so the film approaches the wrapping station straight and flat. Second, the film-pulling rod rotates 10–30° during pulling, increasing the pulling area and preventing film peeling. Third, the upper and lower pressure rollers, each driven by an independent servo with 0.02 mm positioning accuracy, press the film evenly onto the cell body before the folding step.

Q3: How is the insulation film material consumption tracked?

The wrapping module uploads the film material consumption to the MES system. In addition, a material sensor provides a low-film warning, and a material-usage early-warning function alerts the operator before the roll runs out. This data supports production-cost tracking and consumables planning.

Q4: What happens if there is a power or gas supply interruption during operation?

The TOB-SFCA-300 is equipped with power and gas cut-off protection. The robotic arm is designed so that in the event of a power or gas interruption, the battery cells will not fall out and be damaged. When power or gas is restored, the equipment resumes its interlocked, safe operating sequence. The control system also logs the event in the historical alarm records.

Q5: How does the equipment prevent particle contamination of the cell surface?

The TOB-SFCA-300 is designed around strict particle-control requirements. All relatively sliding parts are connected by guide rails or cylinders, eliminating sliding friction; a dust-collection box is installed below the moving parts to capture wear debris; the parts that contact the cell are made of non-metallic materials, with PEEK/PP/POM blocks used at the positioning contact points; and copper, nickel, zinc, and cadmium materials are prohibited within the product passage area. The equipment operates in a Class 10000 environment as specified.

Ready to automate the insulation film wrapping step in your prismatic cell production line? Request a quotation for the TOB-SFCA-300, including a compatibility review for your specific cell dimensions and tray configuration. Our production-equipment engineers can provide a technical proposal and installation-layout recommendation.

tob.amy@tobmachine.com| +86 181 2071 5609

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• Manual Film Wrapping Machine for Prismatic Cells (TOB-MBFW-300) — A manually operated insulation film wrapping workstation for prismatic aluminum-shell cells. Complements the TOB-SFCA-300 by providing a flexible, low-cost wrapping solution for low-volume production, prototype builds, or rework, where an automatic machine is not justified.

• Prismatic Aluminum Case Battery PET Film Wrapping Machine — A PET film wrapping machine for prismatic aluminum-case batteries. Provides an alternative film-wrapping platform for production lines using PET insulation film instead of the film configuration of the TOB-SFCA-300, or for facilities requiring a different throughput configuration.