Lithium-ion Battery Separator

A lithium-ion battery separator is one of the important internal parts of a lithium battery structure. Its main function is to separate the positive and negative electrodes of the battery to prevent the two electrodes from touching or short-circuiting. It also enables the passage of electrolyte ions. Its performance determines the interfacial structure and internal resistance of the battery, which directly affect the battery's capacity, cycle, and safety performance. Toyohashi Chemical can adjust the characteristics of the diaphragm and realize customized production according to the development needs of battery customers.

Performance Characteristics

Dry Separator

Classification Features Microstructure
Dry Separator High performance, tear-resistant 10-25μm
⸺ Multi-component technology
Note: The above test data is for reference only, it can be customized to meet specific requirements.
Inspection Items Unit Standard Value
Model KSG10 KSG12 KSS14 KSG16 KSG20 KSG25
Physical Properties Thickness μm 10 12 14 16 20 25
Breathability s/100ml 180 200 250 280 260 350
Puncture Strength gf 250 300 350 400 420 450
Area Density g/m² 5.6 6.7 7.8 8.7 11.3 13.5
Porosity % 38 38 38 40 38 40
105℃/1h Thermal Shrinkage MD % 1.5 1.5 1.5 1.5 1.5 1.5
105℃/1h Thermal Shrinkage TD % 0.3 0.3 0.3 0.3 0.3 0.3
MD Tensile Strength kgf/cm² 1800 1800 2000 1800 1600 1800
TD Tensile Strength kgf/cm² 160 160 160 160 160 160

Wet Separator

Classification Features Microstructure
Wet Separator Fin-shaped modification, high strength 4~12μm
⸺ Low melting point material
A 7-meter wide separator production line, for higher production efficiency
Note: The above test data is for reference only and can be customized to meet special requirements.
Inspection Items Unit Standard Value
Model KWS05
High strength		 KWS07
High strength		 KWG09
General		 KWH09
High porosity and low air permeability		 KWG12
General		 KWG14
General		 KWG16
General		 KWG20
General
Physical Properties Thickness μm 5 7 9 9 12 14 16 20
Breathability s/100ml 140 140 160 60 180 160 170 180
Porosity % 35 37 39 50 40 42 43 44
MD Tensile Strength kgf/cm² 3200 2800 2800 2000 2800 2500 2500 2200
TD Tensile Strength kgf/cm² 3100 2800 2800 1700 2500 2200 2200 1900
Area density g/m² 3.1 4.2 5.2 4.3 6.8 7.7 8.7 10.6
MD Break Elongation Rate % 85 95 105 98 110 115 115 120
105℃/1h Heat Shrinkage MD % 2 2 2 2 2 2 2 2
105℃/1h Heat Shrinkage TD % 1 1 1 0.5 1 1 1 1

Ceramic Coating Film

Classification Features Microstructure
Ceramic Coating High Heat Resistant CCS Coating 150℃→180℃
Coating Thickness 2~3μm
Low Humidity CCS Coating 800ppm→＜500ppm
Coating Thickness 2~3μm
Note: The above test data is for reference only and can be customized to meet special requirements.
Product Category Performance Aluminum Oxide Coating Bemite Coating
General Low Thermal Contraction Resistance to Humidity and Heat General Low Thermal Contraction Resistance to Humidity and Heat
Single-Sided 2u Coating
△Breathability: ~20 seconds		 Humidity Moisture/ppm 400-600 900-1300 600-800 300-500 800-1100 400-700
Heat Shrinkage <3% at 130℃/1 hour Y Y Y Y Y Y
Heat Shrinkage <5% at 150℃/1 hour - Y - - Y -
Single-Sided 3u Coating
△Breathability: ~30 seconds		 Humidity Moisture/ppm 500-800 1200-1600 900-1100 350-550 1000-1400 500-800
Heat Shrinkage <3% at 130℃/1 hour Y Y Y Y Y Y
Heat Shrinkage <5% at 150℃/1 hour - Y Y - Y Y
Double-Sided 2-3u Coating
△Breathability: ~40 seconds		 Humidity Moisture/ppm 600-900 1600-2200 1000-1400 400-600 1100-1600 600-1000
Heat Shrinkage <3% at 130℃/1 hour Y Y Y Y Y Y
Heat Shrinkage <5% at 150℃/1 hour - Y Y - Y Y

Polymer Coated Film

Classification Features Microstructure
Polymer Coating Water-based PVDF
Low Cost
Oil-based PVDF
High Adhesiveness
Width Speed Upgrade
Cost Optimization
Note: The above test data is for reference only and can be customized to fit specific requirements.
Performance Unit Water-based PVDF Spray Oil-based PVDF
3+2+7+2+3
2-Ceramic
3-PVDF		 5+9+3+5
3-Ceramic
5-PVDF		 9+3+3
3-Ceramic
3-PVDF		 2+5+2
2-Mix Coating		 2+7+2
2-Mix Coating		 1+7+2+1
2-Ceramic
1-PVDF
Model KWG07C22P33 KWG09C03P55 KWG09C03P03 KWG05M22 KWG07M22 KWG07C02U11
Thickness μm 175（10 layers） 220（10 layers） 150 (10 layers) 8 10 11
Breathability s/100ml 220 200 200 140 160 170
Total density g/m² 10.5 12 11 5.7 7.1 9.5
The density of the adhesive layer g/m² 1.2 1.6 0.6 2.6 2.6 1.4

The main uses of lithium-ion battery separators.

In the structure of lithium-ion batteries, the separator is one of the internal components, playing a very crucial role. Lithium-ion batteries can be used in various fields such as electric vehicles, communications, energy storage, data centers, aerospace, electric boats, mobile power sources, smart homes, and electric tools.