Coffee Machine LSR Silicone Food Safety Compliance

NEV Battery Pack LSR Silicone Sealing Solutions

The battery pack of a new energy vehicle is the core component of the entire vehicle, and its safety, sealing performance, and thermal management capabilities directly determine the vehicle range and reliability. LSR silicone sealing components serve three critical functions in battery packs: IP protection, thermal management, and electrical insulation.

I. Core Challenges in Battery Pack Sealing

1. IP Protection Rating

• Battery packs require IP67 or IP68 protection
• Prevent water, dust, and salt spray intrusion causing battery short circuits
• Continuous effectiveness during vehicle wading and car washing

2. Thermal Management Needs

• Battery operating temperature window: 15-35°C, outside this range affects performance and lifespan
• Battery temperature during charge/discharge can reach 60°C; thermal runaway exceeds 150°C
• Seals must withstand -40°C to 150°C wide temperature range

3. Electrical Safety

• Battery pack internal voltage 400-800V, seals must meet insulation requirements
• Dielectric strength ≥ 20 kV/mm, volume resistivity ≥ 1×10¹⁵ Ω·cm
• Flame retardancy UL94 V-0, reducing thermal runaway spread risk

4. Mechanical Loading

• Fastening bolt compression on sealing strip, compression 15-30%
• Driving vibration and impact loads without seal failure
• Cell swelling force: cell expansion during charge/discharge cycles requires seal compensation

II. LSR Sealing Solution Design

1. Battery Pack Lid Seal

• Rectangular cross-section seal strip along lid perimeter
• Compression design 20-25%, ensuring seal contact pressure ≥ 1.5 N/mm
• LSR hardness Shore A 40-50, balancing sealing performance and compression set
• In-mold one-piece forming, no joints, eliminating traditional rubber strip splice leakage points

2. Inter-Module Seals

• Flexible gaskets compensating for manufacturing tolerances between modules
• Thickness 2-5mm, uniform gap filling after compression
• Thermally conductive LSR (1.0-3.0 W/m·K), combined sealing and heat conduction

3. Junction Box/BDU Seals

• Precision seals mating with connector housings
• Multi-chamber design isolating signal and power cable seals
• Dielectric strength and flame retardancy as primary specifications

4. Explosion-Proof Valve Seals

• Waterproof breathable membrane + LSR seal ring combination
• Pressure relief during thermal runaway, water blocking during normal operation
• Valve opening pressure: 2-10 kPa (designable)

III. Material Property Requirements

IV. Manufacturing and Quality Control

1. In-Mold Forming

• Battery pack lid seals up to 2-4 meters, one-piece in-mold forming
• Mold precision ±0.05mm, ensuring seal cross-section consistency
• Vulcanization: 170°C × 60-90 seconds

2. Metal Insert Overmolding

• Junction box seals often include metal inserts
• Insert preheated to 150°C, ensuring strong LSR bond
• Pull test: insert-to-LSR bond strength ≥ 50N

3. Dimensional Inspection

• Seal cross-section optical inspection
• Compression force vs. deformation curve measurement
• Critical dimensions CPK ≥ 1.33

4. Seal Integrity Verification

• Air tightness test: 0.5 bar positive pressure for 5 minutes, leak rate ≤ 0.1 mL/min
• IP67 immersion test: 1m depth for 30 minutes, no water ingress
• Post thermal cycling seal integrity re-verification

NEV battery pack LSR sealing solutions are the critical safeguard for battery safety and reliability, requiring systematic control across the entire chain from materials through design to manufacturing.