Application of Two-Parts A B Silicone Adhesives in PV Modules (Including BIPV Modules)
I. Bonding of Core Components in PV Modules
1. Structural Bonding of Module Frames with Glass/Backsheets
Applicable Components: Bonding and fixing of aluminum alloy frames of crystalline silicon/thin-film modules with front tempered glass and backsheets (PET/TPT composite backsheets, glass backsheets).
Bonding Purpose: Replaces traditional mechanical buckles or screws to achieve "seamless bonding", enhancing module integrity, wind load/impact resistance, and improving waterproof sealing performance to prevent moisture intrusion into the module, which may cause solar cell failure.
Technical Requirements:
Bonding Strength: Tensile shear strength ≥ 0.8MPa (aluminum-glass interface), meeting module wind uplift resistance test (≥ -11kPa);
Weather Resistance: Withstands high and low temperature cycling from -60℃ to 120℃, with performance attenuation ≤ 10% after 5000 hours of UV aging;
Displacement Capacity: Elongation rate ≥ 300%, adapting to deformation caused by thermal expansion and contraction of modules (avoiding frame cracking).
2. Edge Sealing and Structural Enhancement of Dual-Glass Modules
Applicable Components: Bonding and sealing of the four edges of dual-glass PV modules (tempered glass on both front and back sides).
Bonding Purpose: Dual-glass modules have no backsheets, so two-component silicone adhesives are required to achieve the dual functions of "structural bonding + sealing protection". They prevent rainwater and sand from entering the module, enhance the connection strength between glass and frames (or joints of frameless modules), and avoid stress concentration cracking at glass edges.
Application Scenarios: Large-scale ground-mounted PV power plants, BIPV curtain walls/roofs (especially in extreme environments such as coastal areas and high altitudes). Dual-glass modules are relatively heavy (usually ≥ 20kg/㎡), requiring sufficient bonding force from two-component silicone adhesives for support.
3. Bonding and Fixing of Junction Boxes with Module Backsheets
Applicable Components: Bonding of module junction boxes (including lead cables) with backsheets.
Bonding Purpose: Junction boxes are the core of electrical connections in modules. High-strength bonding ensures they do not fall off or shift during transportation, installation, and use. Meanwhile, it seals the gap between junction boxes and backsheets to prevent moisture intrusion leading to short circuits.
Technical Points: Compatible with backsheet materials (e.g., PVDF, PET), with peel strength ≥ 1.5N/mm after bonding, and excellent damp-heat resistance (no debonding after 1000 hours in 85℃/85% RH environment).
II. Bonding of BIPV Modules with Building Structures
1. Structural Bonding of Module Subframes with Main Building Frames
Applicable Components: Bonding of aluminum alloy subframes of BIPV modules with main steel/aluminum alloy frames of buildings in hidden-frame/semi-hidden-frame BIPV curtain walls.
Bonding Purpose: Realizes "inlaid" fixing of BIPV modules, replacing traditional mechanical connectors to ensure the overall flatness of the curtain wall (no visible screws/buckles). It also bears module dead weight, wind load, seismic load, etc., ensuring building structural safety.
Typical Scenarios: Curtain walls of office buildings, skylights of large commercial complexes. Modules are relatively large (common sizes: 1.6m×1.0m, 2.0m×1.2m), requiring two-component silicone adhesives to disperse loads and avoid local stress concentration.
2. Bonding of PV Tiles/Building-Material-Integrated Modules with Building Substrates
Applicable Components: Bonding of BIPV PV tiles with concrete roofs and metal roofs (color steel plates, aluminum-magnesium-manganese plates); fixing of PV wall panels with building wall substrates.
Bonding Purpose: PV tiles/wall panels directly replace traditional building materials. Two-component silicone adhesives achieve "integrated bonding" with building substrates, ensuring wind uplift resistance and dead weight resistance (single PV tile weight ≥ 5kg, requiring bonding strength ≥ 0.6MPa). It also seals splicing gaps to prevent water leakage.
3. Splicing and Fixing of Special-Shaped Modules
Applicable Components: Joints of curved/special-shaped BIPV modules (e.g., domes, special-shaped curtain walls) or customized connections of non-standard size modules.
Bonding Purpose: Traditional mechanical fixing cannot achieve tight fitting of special-shaped modules. Two-component silicone adhesives adapt to the bonding needs of complex curved surfaces, filling irregular gaps (gap width adjustable from 1-10mm) while maintaining bonding strength and sealing performance.
III. Bonding of Special Functional Components (High-End/Customized Modules)
1. Integrated Bonding of Modules with Energy Storage Modules
Applicable Components: Bonding and fixing of energy storage modules (lithium battery modules integrated on the back of modules) with module backsheets/frames in PV modules with energy storage functions.
Bonding Purpose: Ensures stable connection between energy storage modules and PV modules, withstanding vibration (during transportation) and temperature changes (heat generation from energy storage modules). It also has certain thermal conductivity and buffer performance to avoid local overheating.
2. Special Bonding for PID-Resistant Modules
Applicable Components: Bonding of frames with glass/backsheets in PID (Potential Induced Degradation)-resistant modules, or fixing of internal insulation layers in modules.
Bonding Purpose: Two-component silicone adhesives can improve insulation performance by adding special fillers (e.g., MgAl-LDHs), reducing the risk of leakage between module frames and solar cells, delaying PID attenuation, and extending module service life (≥ 30 years).
IV. Inapplicable Scenarios for Two-Component Silicone Adhesives
Bonding of solar cells with glass inside modules (EVA/POE film is required instead of silicone adhesive);
Temporary fixing or light-load scenarios (e.g., temporary splicing of small-size modules, where one-component silicone adhesive is sufficient);
Direct bonding with polyolefin materials (e.g., PE, PP) (surface activation treatment is required first, otherwise bonding strength is insufficient).
