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Innovative Application of Plastic Fasteners in New Energy Vehicle Battery Pack Structures

As the new energy vehicle (NEV) industry grows explosively, demand for lightweight, high-reliability battery pack structures continues to surge. Traditional metal fasteners face three bottlenecks in battery packs: high density increases vehicle weight, electrochemical corrosion risks short circuits, and mismatched thermal expansion coefficients cause connection failure. Zhuhai Jiali Hardware Co., Ltd. leverages its 15-year R&D experience in plastic fasteners to introduce a plastic material system into NEV battery pack structures for the first time—achieving a technological leap from 'weight reduction' to 'efficiency enhancement'.

I. Dual-Thread Anti-Loosening Principle

This solution adopts an 'upper nut (standard thread) + lower nut (reverse thread)' dual-thread locking mechanism:

• Step 1: The lower nut contacts the mating part first, establishing initial clamping force
• Step 2: The upper nut continues tightening, applying axial pressure to the lower nut, causing its threads to elastically deform
• Step 3: Even under severe vibration, the counterforce generated by elastic deformation prevents thread loosening

II. Standard Installation Procedure (4-Step)

1. Cleaning: Thoroughly clean mating surfaces and bolt threads with acetone to remove oil, rust, and old sealant.

2. Placement: Install the lower nut as a pair on the battery pack housing, ensuring it contacts the mating part first.

3. Tightening: Use a calibrated torque wrench in three stages:

• Stage 1: 50% recommended torque → initial clamping by lower nut
• Stage 2: 75% recommended torque → upper nut compresses lower nut
• Stage 3: 100% recommended torque → final locking

4. Marking: After tightening, draw a straight line with permanent marker across the nut edge and mating part. Misalignment indicates loosening and requires immediate re-tightening.

III. Recommended Torque Values (ISO 898-1 Class 10.9)

This solution supports full-size M6–M24 bolts. Recommended torque values are:

• M6: 12.0 N·m
• M8: 32.0 N·m
• M10: 65.0 N·m
• M12: 112.0 N·m
• M16: 280.0 N·m
• M20: 560.0 N·m
• M24: 960.0 N·m

Conclusion

The cross-domain collaboration between plastic fasteners and NEV battery packs is not simple material transplantation—it's deep evolution driven by real customer scenarios. Jiali will continue investing in AI selection engines, digital twin simulation, and green supply chain construction to make fastener procurement for China's NEV industry more efficient, reliable, and sustainable.