New Energy Vehicle Battery Pack Fastening Solutions: Why are Combination Screws (such as Pan Head Screws with Washers) Specified?

The core of a new energy vehicle is the battery pack; it's not only the "heart" of the vehicle but also crucial for safety. In this precise and expensive component, every detail is critical—including those seemingly tiny screws. In recent years, combination screws (especially pan head screws with washers) have become the preferred battery pack fastening solution. What engineering wisdom lies behind this?

I. The Special Challenges of Battery Pack Fastening

Battery packs differ from traditional mechanical components, facing a unique working environment:

Continuous Vibration: Vibrations of different frequencies generated during vehicle operation may loosen fasteners.

Current Risk: Loose screws may generate electric arcs, causing serious safety accidents.

Thermal Expansion and Contraction: Temperature changes during battery charging and discharging affect connection stability.

Space Constraints: Compact designs require fasteners to simultaneously meet small size and high strength requirements.

Corrosion Resistance Requirements: Corrosive gases may be generated inside the battery pack.

These stringent conditions make ordinary screws unsuitable.

II. Superior Advantages of Combination Screws

1. Reliability of Integrated Design

Combination screws integrate the screw and washer in a single manufacturing process, eliminating the risk of separation under vibration inherent in traditional screw + washer combinations. This integrated structure ensures the washer remains in the correct position, providing a consistently stable anti-loosening effect.

2. Improved Assembly Efficiency

On automated production lines, combination screws reduce the number of parts, simplify the feeding system, and significantly increase assembly speed. For battery pack production lines producing hundreds of thousands of units annually, every second saved translates into considerable benefits.

3. Stable Contact Performance

The flat bottom surface of the pan head washer screw combined with the spring washer ensures uniform contact pressure. This design effectively disperses preload, preventing deformation of the connectors due to pressure concentration, while providing excellent electrical continuity.

4. Superior Anti-Loosening Performance

The spring washer element in the combination screw generates continuous elastic restoring force during tightening, effectively compensating for preload loss caused by vibration and temperature changes. This characteristic is crucial for battery pack safety.

III. Special Requirements for Materials and Processes Battery pack assembly screws not only feature a special design but also adhere to higher standards in materials and processes:

Material Selection: Typically made of 304 or 316 stainless steel, providing excellent corrosion resistance and appropriate strength.

Surface Treatment: Enhanced corrosion resistance through treatments such as galvanizing and Dacromet coating, while ensuring good electrical conductivity.

Precision Control: Thread precision reaches 6g level or higher, ensuring consistent and reliable fit.

Torque Consistency: Each batch of screws maintains a stable coefficient of friction, ensuring assembly quality.

IV. Nanning Aozhan's Professional Solutions In the field of new energy vehicle battery packs, where safety requirements are extremely high, Nanning Aozhan, with its professional technical strength, provides reliable assembly screw solutions for numerous clients.

Our product advantages are reflected in:

Professional Design: Structural design optimized for the specific needs of battery packs

Material Guarantee: Providing a complete material certification and traceability system

Rigorous Testing: Every batch of products undergoes vibration testing, salt spray testing, and torque testing

Customization Capability: We can provide personalized solutions according to customers' specific needs

We deeply understand the importance of battery pack safety, therefore we implement strict control over every aspect of the production process to ensure that every screw delivered meets the most stringent quality requirements.

V. Selection Recommendations

When selecting combination screws for battery packs, we recommend focusing on:

Verifying the supplier's quality management system certification

Requesting complete performance test reports

Considering the electrochemical compatibility of the screws and connecting materials

Assessing the supplier's technical support capabilities

If you are looking for a reliable fastening solution for your new energy vehicle battery packs, Nanning Aozhan is a partner you can trust. We invite you to contact us and let us provide the safest and most reliable connection guarantee for your battery pack with our professional combination screw products.