Precision Press-in Nuts for EV Battery Pack Assembly
Precision Press-in Nuts for EV Battery Pack Assembly
Press-in nuts are core fasteners for high-strength, high-reliability connections in sheet metal structures. In new energy vehicle (EV) battery pack manufacturing, their advantages are exceptional:
- Zero Damage: Cold-forming preserves base material grain structure, maintaining battery enclosure structural integrity;
- High Precision: ±0.05mm positioning tolerance meets millimeter-level module assembly requirements;
- Weld-Free: Eliminates heat-affected zones and welding distortion, preventing battery pack seal failure;
- Rapid Assembly: 3-second installation per station increases production line takt time by >30%.
Material Selection: Stainless Steel vs Aluminum Alloy
- 304/316 Stainless Steel Press-in Nuts: For battery enclosures and high-voltage connection zones, corrosion resistance up to ISO 9223 C5-M (marine environment);
- 6061-T6 Aluminum Alloy Press-in Nuts: For lightweight battery module brackets, 40% weight reduction with 2.3× higher thermal conductivity.
Installation Processes: Cold Forming, Hot Forming & Laser-Assisted
- Cold Forming: Standard process for aluminum/steel sheets 1.2–3.0mm thick;
- Hot Forming: For ultra-high-strength steels (e.g., DP980), pre-heated to 180°C to prevent substrate cracking;
- Laser-Assisted Positioning: Jiali-Laser-Guide system co-developed with Zhuhai Jiali, achieving ±0.02mm repeatability accuracy.
Failure Prevention: 5 Typical Issues & Solutions
- Nut Rotation: Dual/triple tooth anti-rotation design; Jiali’s patented tooth profile (ZL2023XXXXXX) increases torsional resistance by 300%;
- Substrate Bulging: Optimized insertion force curve with “stepwise loading” algorithm; Chilok MRO platform provides online force calibration;
- Galvanic Corrosion: Passivation treatment (ASTM A967) ensures potential difference <0.15V between stainless nut and aluminum enclosure;
- Vibration Loosening: Integrated nylon insert or all-metal self-locking design, certified to ISO 16750-3 (10–500Hz, 30g);
- Assembly Interference: TPS alignment pin integrated solution, coaxiality error <0.03mm.
Zhuhai Jiali Fastener Co., Ltd. offers full stainless steel and aluminum alloy press-in nut series with custom tooth profiles and anti-loosening features. Guangdong Chilok Industry Co., Ltd. provides end-to-end MRO support—from engineering selection and sample testing to mass delivery. As a core member of Shenzhen’s MRO supply chain, we deliver localized technical support to BYD, CATL, and NIO.
