The application of liquid silicone in the field of new energy is constantly expanding. With its excellent physical and chemical properties, it provides important support for the performance improvement, safety assurance and reliability enhancement of new energy equipment. The following analyzes the application of liquid silicone from multiple new energy sub-sectors:
1. Lithium battery field
Battery packaging and insulation
As a packaging material, liquid silicone can form a flexible and dense protective layer, effectively isolating moisture, oxygen and impurities, and improving the weather resistance and safety of the battery. Its excellent insulation performance can prevent internal short circuits in the battery and ensure the stable operation of the battery in extreme environments such as high temperature and high humidity.
Thermal management and heat dissipation
Liquid silicone has high thermal conductivity (up to 1-3 W/m·K) and can be made into thermally conductive gaskets or potting glue to quickly transfer the heat generated by the battery to the heat dissipation system to avoid performance degradation or thermal runaway risks caused by local overheating.
Structural bonding and buffering
The elastic modulus of liquid silicone is adjustable (1-10 MPa), which can not only provide sufficient structural strength, but also absorb the volume change stress during battery charging and discharging, thereby extending the battery cycle life.
2. Photovoltaic module field
Edge sealing and moisture-proofing
Liquid silicone is used for sealing the frame of photovoltaic modules, which can replace traditional silicone glue. It has better UV aging resistance (no yellowing in 30 years), and no volatile organic compounds (VOC) are released after curing, which meets environmental protection requirements.
Junction box potting
Liquid silicone potting junction boxes can prevent water vapor intrusion, protect internal diodes and connectors, reduce PID (potential induced decay) risks, and improve long-term reliability of components.
Flexible connection
Liquid silicone can be made into flexible conductive tape for electrical connection between photovoltaic modules. Its flexibility can adapt to deformation during installation and reduce the risk of microcracks.
3. Hydrogen energy field
Fuel cell sealing
Liquid silicone is used for fuel cell stack sealing. It can withstand a wide temperature range of -40℃ to 120℃, and has excellent barrier properties to gases such as hydrogen and oxygen (permeability <1×10⁻¹⁴ cm³·cm/(cm²·s·Pa)), ensuring the airtightness of the stack.
Bipolar plate bonding
Liquid silicone can bond graphite bipolar plates and metal end plates, and its bonding strength can reach more than 5 MPa. It also has electrical insulation to prevent short circuits between bipolar plates.
Hydrogen storage bottle packaging
Liquid silicone is coated on the inner wall of the hydrogen storage bottle to form a dense protective layer to prevent hydrogen molecules from penetrating and extend the service life of the hydrogen storage bottle.
4. Wind energy field
Blade bonding and repair
Liquid silicone is used for bonding and repairing wind turbine blades. It has excellent fatigue resistance (up to 10⁷ cycles) and low shrinkage after curing (<0.1%), which can avoid stress concentration during blade operation.
Pitch bearing seal
The seal made of liquid silicone can withstand temperature changes from -30℃ to 80℃, and has good compatibility with grease to prevent bearing lubricant leakage.
5. Technical advantages of liquid silicone
Adjustable material properties: By adjusting the formula, the hardness (10-80 Shore A), viscosity (1000-100000 cps), curing speed (5-120 minutes) and other parameters can be customized.
Strong process compatibility: Supports multiple molding methods such as injection molding, coating, and potting, and adapts to the needs of automated production lines.
Environmental compliance: Complies with environmental regulations such as RoHS and REACH, and some products have passed UL94 V-0 flame retardant certification.
6. Application cases
Tesla Model 3 battery pack: Using liquid silicone potting technology to achieve IP67 waterproof level, while reducing the weight of the battery pack by 5%.
Longi Green Energy Photovoltaic Module: Using liquid silicone frame sealing, the module life is extended to more than 30 years, and the PID attenuation rate is less than 3%.
Toyota Mirai Fuel Cell: Liquid silicone seals the stack, and the airtightness reaches 1×10⁻⁶ Pa·m³/s, ensuring the stable operation of hydrogen fuel cells.
The application of liquid silicone in the field of new energy is developing from a single function to a multi-functional integration. In the future, with the further improvement of material performance (such as self-healing, conductivity, etc.), its application scenarios will be more extensive, providing key support for the lightweight, high efficiency and safety of new energy equipment.