At Nexway EV, a professional manufacturer of
EV charging connectors, AC EV chargers, and charging accessories, we understand that housing design directly impacts product quality and user experience. The two most common housing molding methods in the industry are integrated (one-piece) and split (multi-piece) structures. Each approach presents unique material requirements, manufacturing challenges, and performance characteristics.
This article explores the differences between these two designs and provides guidance for selecting the optimal solution.
Integrated EV Charging Gun Housing: Designed for Complex Structures and High Durability
An integrated charging gun housing is manufactured as a single molded component, providing superior structural integrity and minimizing assembly-related risks. However, the complex mold design and injection molding process place higher demands on material performance.
Key Material Requirements
1. Excellent Weather Resistance and Temperature Performance
Outdoor charging connectors must withstand extreme environmental conditions, including temperatures ranging from -40°C to high-temperature operating environments, as well as prolonged UV exposure.
To prevent cracking, discoloration, and mechanical degradation, silicone-modified polycarbonate (Silicone-PC) materials are often preferred due to their:
- Outstanding UV resistance
- Low-temperature impact resistance down to -40°C
- Long-term weatherability
2. Low Internal Stress Characteristics
Polycarbonate materials can develop internal stress during injection molding. In integrated housing designs, the complex geometry can further amplify this issue.
By incorporating siloxane-PC copolymers, manufacturers can:
- Reduce molding stress
- Improve dimensional stability
- Enhance long-term durability
- Minimize the risk of stress cracking
3. Compliance and Safety Performance
Materials used in integrated charging connector housings should comply with international environmental and safety standards, including:
- RoHS
- REACH
- Halogen-Free (HF) requirements
- UL certification standards
Additionally, the housing material should provide:
- UL94 V-0 flame-retardant performance
- Stable electrical insulation
- High mechanical strength
- Reliable operational safety
Split EV Charging Gun Housing: Balancing Performance and Cost Efficiency
A split housing consists of multiple molded components assembled into the final charging connector. This design offers significant advantages in manufacturing flexibility and cost control.
Benefits of Split Housing Design
- Simpler individual component structures
- Reduced mold complexity
- Lower tooling investment
- Easier production scalability
- Improved manufacturing efficiency
Despite these advantages, split housings must still maintain the same outdoor performance and safety standards as integrated designs.
Key Material Requirements
1. Weather and Temperature Resistance Remain Essential
Split housings are also exposed to outdoor conditions throughout their service life.
Required material properties include:
- Resistance to temperatures as low as -40°C
- UV stability
- Weather resistance
- Long-term mechanical durability
Silicone-PC materials continue to be a preferred solution due to their balanced performance profile.
2. Cost-Effective Performance Optimization
Materials should provide:
- RoHS, REACH, and HF compliance
- UL94 V-0 flame retardancy
- Stable electrical properties
- Adequate mechanical strength
At the same time, optimized formulations help manufacturers maintain the cost advantages associated with split-housing production.
3. Multi-Mold Injection Compatibility
Because different housing sections are produced using separate molds, material flow characteristics become critical.
The material should offer:
- Excellent mold filling capability
- Stable processing behavior
- Consistent dimensional accuracy
- Reduced assembly tolerances
These factors help improve production efficiency and ensure reliable final assembly.
Comprehensive Testing Requirements for EV Charging Gun Housings
Whether using an integrated or split design, charging gun housings must pass rigorous validation tests to ensure long-term reliability and user safety.
Environmental Aging Test
Xenon arc weathering tests simulate years of outdoor exposure by combining:
- UV radiation
- Temperature cycling
- Humidity variations
- Water spray exposure
The testing process evaluates resistance to:
- Cracking
- Color fading
- Material degradation
- Mechanical performance loss
Mechanical Strength Test
High- and low-temperature crush testing verifies housing durability under extreme conditions.
Typical procedures include:
- 24-hour exposure at -40°C
- 24-hour exposure at 23°C
- Vehicle wheel crush testing under approximately 5000 N load
After testing, the connector housing must remain functional without significant deformation or damage.
Odor Evaluation
Non-metallic housing components, cables, plugs, and control boxes undergo odor testing to ensure a pleasant user experience and compliance with quality standards.
Electrical Tracking Resistance Test
According to relevant standards, the housing material must withstand electrical tracking tests without flashover or breakdown before completion of the required test cycles.
Heat Resistance Test
The housing must maintain its structural integrity when exposed to elevated temperatures.
Requirements include:
- No cracking or deformation
- No leakage of sealing materials onto live parts
- Clear and legible markings
- Stable mechanical performance
Glow-Wire and Fire Resistance Testing
To reduce fire risks during charging operations, housing materials undergo glow-wire and flammability testing.
Performance criteria include:
- No sustained flame
- No persistent glowing combustion
- No ignition of surrounding materials
- Compliance with UL94 V-0 standards
How to Select the Right Housing Material
Choosing the appropriate material requires balancing performance, manufacturing complexity, and cost objectives.
For Integrated Charging Gun Housings
Recommended materials include high-silicone or standard silicone-modified PC compounds that provide:
- Superior weather resistance
- Low internal stress
- Excellent low-temperature performance
- Reliable processing characteristics
These materials are particularly suitable for complex geometries and demanding outdoor applications.
For Split Charging Gun Housings
Material selection should consider:
- Number of molds involved
- Component complexity
- Cost targets
- Production volume
An optimized silicone-PC formulation can deliver:
- -40°C impact resistance
- UV protection
- Stable molding performance
- Cost-effective manufacturing
The Nexway EV Approach to Durable Charging Connector Design
As a dedicated supplier of EV charging connectors, Type 2 charging plugs, CCS2 charging connectors, and complete EV charging solutions, Nexway EV places strong emphasis on material selection, structural design, and rigorous product testing.
Whether developing integrated or split charging gun housings, selecting the right material system is essential for achieving:
- Long service life
- Outdoor durability
- Electrical safety
- Manufacturing efficiency
- Compliance with global standards
By understanding the strengths and limitations of each molding approach, manufacturers can build safer, more reliable charging products that meet the evolving demands of the global EV market.
