Wet Process Separator 9μm

Product Overview

Huizhou BestGemo New Energy presents the Wet Process Lithium Battery Separator in a 9-micron thickness, a polyethylene (PE) base film engineered specifically for power and energy-storage lithium battery applications. This separator is produced using the wet process method, which yields a uniform microporous structure that balances high ionic conductivity with robust mechanical integrity. As a general-purpose base film, it is designed to meet the core performance demands of modern battery cells, providing a reliable physical and electrochemical barrier between the anode and cathode.

The 9μm variant offers a well-balanced profile for manufacturers seeking a combination of energy density and mechanical robustness. Its slightly thinner construction compared to 12μm and above allows for higher volumetric energy density, while still maintaining sufficient tensile strength for reliable high-speed winding and cell assembly. Each roll is produced under stringent process controls to deliver consistent porosity and permeability, ensuring predictable electrolyte wetting and ionic transport across the entire electrode surface. The 9μm thickness is a versatile choice for applications where space is at a premium but durability cannot be compromised.

Key Features

• High ionic conductivity enabled by a uniform porosity of 40±4%, facilitating efficient lithium-ion transport and reduced internal resistance.
• Robust mechanical strength with MD tensile strength of 1,500 to 3,000 MPa and TD tensile strength of 1,300 to 2,800 MPa, supporting high-speed winding and cell assembly without tearing even at this thinner gauge.
• Controlled thermal shrinkage of ≤3% (MD) and ≤2% (TD) at 90°C, contributing to electrode alignment stability and reducing the risk of internal short circuits during thermal exposure.
• Optimized air permeability ranging from 130 to 210 sec/100cc, ensuring balanced gas exchange during formation and consistent electrolyte penetration.
• Precise 9μm thickness with a corresponding square weight within the range of 4.2 to 10.7 g/m², enabling accurate cell design tuning for high-energy-density applications.
• Polyethylene wet-process base film chemistry that delivers intrinsic chemical stability against common liquid electrolytes and additives.

Technical Specifications

Applications

This 9μm wet-process separator is a dedicated solution for power lithium batteries—such as those used in electric vehicles, hybrid vehicles, and high-rate power tools—as well as for energy-storage batteries deployed in stationary grid storage, uninterruptible power supplies, and renewable energy integration systems. The 9μm thickness is particularly well-suited for applications where maximizing energy density within a constrained cell volume is a priority, such as in compact EV battery packs or slim portable power stations. Its balanced performance profile makes it suitable for cells that require reliable cycling, moderate to high discharge rates, and consistent thermal behavior.

• Electric vehicle (EV) and hybrid electric vehicle (HEV) battery cells where space efficiency is critical.
• Utility-scale and residential stationary energy storage systems.
• High-rate discharge power battery packs for industrial equipment.
• Backup power and load-leveling battery modules for commercial facilities.
• Portable power stations and solar-plus-storage configurations.

Quality Assurance

• Strict quality management is applied throughout each production stage, from raw material intake to slitting and final packaging.
• Every batch undergoes full inspection prior to shipment, including verification of thickness, porosity, permeability, tensile strength, and thermal shrinkage against stated specifications.
• Technical support is available to assist with product selection, application guidance, and troubleshooting during cell assembly trials.
• Samples are available upon request for internal evaluation and compatibility testing before volume procurement.

OEM/ODM Customization

Huizhou BestGemo New Energy offers flexible customization for the Wet Process Lithium Battery Separator to align with varying battery design requirements. Finished width can be tailored to a customer’s precise needs, whether for narrow prismatic cells or wide pouch formats. Additionally, while 9μm is the standard offering for this variant, we can adjust square weight and air permeability within the stated ranges to meet specific performance targets. Our engineering team will work with you to specify the correct parameters based on your cell chemistry, electrode coating, and assembly equipment, ensuring the separator integrates seamlessly into your production line.