With the rapid development of the new energy vehicle market, as a core component for energy transmission, the cost control and optimization of high-voltage wiring harnesses have become the key for automakers to enhance their competitiveness. Wire harness experts conduct an analysis from three dimensions: cost structure, quotation process, and cost reduction strategies. By integrating industry practice and technological innovation, they systematically expound the full life cycle management methods for EV high-voltage wire harnesses.

I. In-depth Analysis of High-Voltage Wiring Harness Costs

(1) Cost composition model

The total cost of HV wiring harnesses consists of material costs (73.8%), processing fees (14.7%), packaging and transportation fees (2%), and management fees (9.5%). Among them, the proportion of material costs is the highest, specifically including:

1. High-voltage connectors (55%) : They are responsible for electrical connection and signal transmission. The price difference between foreign brands (such as TE) and domestic brands (such as Luxshare) can reach 30%.

2. High-voltage cables (35%) : Copper conductor materials are dominant, with a cross-sectional area range of 16-150mm². The cost increases exponentially with the increase in wire diameter. Take a 50mm² cable as an example, the cost per meter is approximately 50 to 80 yuan.

3. Coating materials (6%) : including corrugated tubes, heat shrink tubes, etc., with a temperature resistance grade of over 150℃. Although the cost proportion is low, it affects the protective performance.

4. Other auxiliary materials (4%) : Shielding layer (aluminum foil + braided copper mesh), guard plate, etc. The material selection directly affects the EMC performance.

(II) Cost-sensitive factors

1. Wiring harness length: After the fast charging wiring harness length of a certain model was optimized from 4 meters to 2.5 meters, the cost decreased by 260 yuan.

2. Number of connectors: The high-voltage system architecture has been optimized to reduce 4 connectors, which can save 730 yuan in costs.

3. Process complexity: Replacing the crimping process with ultrasonic welding can increase efficiency by 15%, but the equipment investment increases by 20%.

Ii. Quotation Process and Key Control Points for High-Voltage Wiring Harnesses

(1) Standardized quotation process

In the requirements confirmation stage, obtain the vehicle's electrical schematic diagram, 3D wiring diagram and technical parameters (voltage level, current load, etc.).

2. Clearly define core indicators such as protection level (IP67/IP6K9K) and EMC shielding effectiveness (≥85%).

3. Use CATIA for 3D wiring simulation to avoid mechanical interference and optimize the path, reducing the length of the wiring harness by 10% to 15%.

4. Select the connector model (such as HVP800 series) and cable specification to form a BOM list.

5. Cost accounting Model:

5.1 Material cost: Calculated based on the unit price of cables (such as 70 yuan per meter for 50mm² copper cables) and the unit price of connectors (approximately 150 yuan per set for domestic products).

5.2 Processing fees: Priced by process, including crimping (0.5 yuan per point), shielding treatment (1.2 yuan per meter), etc.

5.3 Additional charges: Packaging and transportation (3-5 yuan per set), testing and certification (for example, QC/T 1037 testing fee is approximately 5,000 yuan per batch).

6. Comprehensive quotation output

6.1 Provide itemized quotations and reserve a margin of 5% to 10% for engineering changes.

(II) Key Links in Cost Control

1. Design collaboration: Conduct joint reviews with the original equipment manufacturer to avoid redundant functional designs (such as combining HVH and PTC functions to save 1.5m of wiring harnesses).

2. Supplier Management: Establish a certification system for domestic connectors (such as Ebusbar) to replace TE, reducing procurement costs by 25%.

3. Process validation: Through DOE tests, the crimping parameters (pressure of 3-5 tons, holding time of 0.5 seconds) were optimized, increasing the yield to 99.5%.

Iii. Systematic Cost Reduction Plans and Practical Cases

(1) Optimization of high-voltage system architecture

Module integration: Integrate the PDU (high-voltage distribution box) with the IPU (inverter), reducing 1.5m 50mm² cables and 2 pairs of φ8mm terminals, and lowering the cost by approximately 400 yuan per set.

Function integration: Merge the HVH (battery heating) and PTC (occupant heating) circuits, saving 1.5m of 3mm² wiring harnesses and 2 pairs of connectors, reducing costs by 130 yuan.

(2) Wiring harness layout and material optimization

Topology reconfiguration: The fast charging port was moved from the rear side panel to the front fender, and the length of the wiring harness was shortened from 4m to 2.5m, reducing the cost by 260 yuan.

Scientific selection of wire diameter: Based on thermal simulation (ΔT≤55K) and current-carrying capacity calculation, the fast-charging cable has been optimized from 70mm² to 50mm², reducing the cost per vehicle by 200 yuan.

Domestic substitution: Luxshare HVP800 connectors are adopted to replace TE products of the same specification, reducing the unit price from 220 yuan to 150 yuan, a decrease of 32%.

(3) Innovation in production processes

Automation upgrade: The introduction of a six-axis robot wiring system reduces manual intervention, increasing production efficiency by 40% and lowering labor costs by 25%.

Platform-based design: Unify the opening size of battery pack panels, be compatible with TE and Luxshare connectors, and reduce mold costs by 50%.

(4) Cost reduction through supply chain collaboration

VAVE Value Project: Jointly developed an integrated charging socket with suppliers, reducing one set of flange molds and cutting costs by 8 yuan per piece.

Large-scale procurement: Through platform-based design, the number of connector types has been reduced from 200 to 6, and the procurement cost has decreased by 18%.

Iv. Future Trends and Technological Outlook

Material innovation: Explore alternative solutions to aluminum wires. Although the cross-sectional area needs to be increased by 30%, the weight can be reduced by 45% and the cost by 50%. Anti-oxidation coating process is required.

Intelligent detection: By applying machine vision and AI algorithms to achieve online detection of terminal crimping quality, the defect detection rate has been increased to 99.8%.

Industry standardization: Promote the unification of connector interfaces (such as Tesla's announcement of six standard interfaces), reducing compatibility costs by more than 20%.

V. Expert Summary

The cost management of high-voltage wiring harnesses for new energy vehicles is a systematic project that requires collaborative optimization from multiple dimensions including design, manufacturing, and supply chain. Through strategies such as architecture integration, domestic substitution, and process upgrading, the cost of a single set of wiring harnesses can be reduced by 15% to 20%. In the future, with the innovation of materials and the application of intelligent technologies, high-voltage wiring harnesses will continue to evolve towards lightweight and high integration, providing stronger cost competitiveness for the popularization of new energy vehicles.

(Note: The data and cases in this article are based on publicly available industry research. The specific parameters are subject to the actual project.)