Battery Separator Films

Excellent Product Quality in the Production of Battery Separator Films

Coperion has vast experience and has handled many projects, from R&D lab scale up to complete production lines, for all major battery components, i.e. compounding of cathode and anode materials, separators for lead-acid batteries and lately an increasing number of separators for Li-ion batteries.

The separator is a key component of every Li-ion battery, which is located between the anode and cathode and separates those two electrodes from each other to prevent internal short circuits, which at worst can lead to a fire or even an explosion. Hence, the separator plays an important role, when it comes to battery safety and reliability. Most battery separators are currently made out of polyolefins, where Coperion’s twin screw extruder systems have gained years of experience. Due to comprehensive engineering know-how, customized screw design and high process reliability Coperion systems ensure excellent quality of the final product.

Your benefits at a glance

  • Comprehensive engineering and process know-how in the production of battery components
  • High-end twin-screw extruders
  • Best in class reliability
  • Various formulations tested in our lab tests
  • High mixing performance, homogeneity
  • Highest throughput rates with high quality levels ensures optimum product quality
  • Maximum economic efficiency
  • Versatility

For large-scale commercial production of microporous separators for Li-ion batteries there are two basic manufacturing processes. The so called wet process (with up to 70% oil) and dry process, both covered and distributed by Coperion. Especially the very demanding wet process requires precise machinery and feeding equipment to meet the narrow quality tolerances the market is looking for. Formulations with different levels of oil and polymers (PP/PE/UHMWPE) have been successfully tested in our lab to provide machines for various throughput rates and have been supplied to customers.

Coperion also plays a major part in turnkey stretching lines and works together with renowned companies for the production of battery separator films. We provide first-class feeding equipment and high-end twin screw extruders as excellent core components for these systems. Coperion inside – for highly sophisticated separators. With Coperion extruders and feeding equipment, film lines are able to combine highest output rates with high quality levels and best in class reliability. Coperion’s constant endeavor to increase the throughput of separator film lines makes Li-ion batteries more economic.

Typical Applications

  • Automotive (electric vehicles)  
  • Consumer electronics: Laptop computers / mobile phones / tablet PCs / cameras
  • Large scale stationary power devices
  • High power applications, tools, etc.

Comprehensive product range

Coperion twin screw extruder ZSK 82 Mc18

Compounding Machines and Extruders

With its specific torque of 18 Nm/cm3, the ZSK Mc18 twin screw extruder impresses with its extremely high throughput rates, optimum product quality and maximum economic efficiency and the the ideal solutions for the production of battery separator films.

ZSK Mc18 Twin Screw Extruder

High-accuracy Feeding Solutions

Coperion K-Tron feeders are characterized by their high accuracy and reliability. With extensive expertise and a wide range of feeding solutions, Coperion K-Tron offers the right feeder for every application. 

With precise control and information about the bulk solids being fed, you benefit not only from adherence to the exact recipe, but also from reduced maintenance and less downtime. The result is a stable process with reduced costs.

Feeding Solutions
Coperion Service


With our comprehensive range of services Coperion and Coperion K-Tron are able to ensure maximum productivity and operational reliability of your compounding lines.

Comprehensive range of services

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