2025-07-17   Lankwitzer

UV Coating Technology: Breaking Through PET Blue Film

 Limitations and Leading Battery Safety Upgrades

In lithium-ion battery manufacturing, insulation coating is a critical component for ensuring battery safety and durability. Although traditional 

technologies like PET blue film are widely used, they still suffer from inefficiency and insufficient adhesion. With the rapid development of new

 energy vehicles toward high-voltage and high-energy-density systems, these conventional methods can no longer meet the safety requirements 

of next-generation batteries.  

As an industry technology pioneer, BMW has taken the lead in applying Lankwitzer (Germany) UV coating technology to battery insulation, 

achieving a more environmentally friendly and higher-quality insulation solution while enhancing production efficiency.  

Why Did BMW Choose UV Coating Technology?  

Electric vehicles demand higher standards for lightweighting, corrosion resistance, and insulation performance. 

UV coating technology delivers:  

① Ultra-Fast Curing: Cures within seconds (1-3 sec) under UV light, significantly shortening production cycles and improving output.  

② Superior Adhesion: Compatible with metals, plastics, and composite materials, ensuring long-term coating durability.  

③ Excellent Weather Resistance: Resists UV aging and chemical corrosion, making it ideal for high-voltage components like battery packs and motors.  

Why Can’t Traditional PET Blue Film Meet Next-Gen Battery Needs?

① Safety Limits:  

With the adoption of 800V high-voltage fast-charging technology, battery systems require insulation materials with higher dielectric strength. 

However, PET film typically only withstands up to 2500V, posing insulation failure risks. Additionally, China’s mandatory standard GB 38031-2025 

stipulates that battery pack insulation resistance must be ≥100 Ω/V. Traditional blue film solutions degrade over time due to aging and edge warping,

 making compliance difficult.  

② Structural Weaknesses:  

Next-gen battery designs (e.g., CTP, CTB, CTC) integrate cells directly into battery packs or vehicle chassis, requiring shear strength of 9-15MPa.

 However, PET film's pressure-sensitive adhesive (PSA) only provides 0.5-2MPa bonding strength. Under mechanical stress, the film is prone to 

delamination or cohesive failure, increasing short-circuit and thermal runaway risks. In contrast, UV coating forms chemical bonds with battery

 substrates, achieving >10MPa shear strength-perfect for advanced battery structures.  The Future of Battery Insulation  as energy density continues to rise, 

UV coating technology is becoming the standard solution for premium batteries due to its outstanding electrical, mechanical, and process advantages.

This innovation not only addresses current safety concerns but also provides headroom for future 1000V+ ultra-high-voltage platforms

Choosing UV Coating Means Choosing: 

With BMW and other industry leaders adopting this technology, UV coating is reshaping the roadmap for battery insulation, driving the entire industry 

toward safer and more efficient solutions.