GB/T 33341-2025 in English

Background and Significance of the GB/T 33341-2025 Standard Revision

GB/T 33341-2025, "Electric Vehicle Quick-Swap Battery Box Rack," serves as a key national standard replacing the 2016 version, marking a new stage in the standardized and regularized development of electric vehicle battery swapping technology in my country. Proposed and coordinated by the China Electricity Council, the standard was co-drafted by over 30 organizations, including Shanghai Qiyuanxin Power Technology Co., Ltd., reflecting the consensus of all sectors of the industry and technological development trends.

This revision, primarily driven by the rapid development and technological iteration needs of electric vehicle battery swapping technology, has made structural adjustments to the 2016 version of the standard and updated its technical content. Important sections have been added, including interchangeability requirements, structural types, mechanical requirements, test methods, and inspection rules, while some outdated technical requirements have been deleted, bringing the standard more in line with current technological developments and market demands.

Main technical changes and updates

Compared with the 2016 version, GB/T 33341-2025 has made significant adjustments to the technical content:

Detailed Explanation of Key Technical Requirements

Specifications for Environmental Operating Conditions

Chapter 4 of the standard specifies the environmental operating conditions for battery racks: ambient temperature -20°C to +65°C, daily average maximum relative humidity of 95% and monthly average maximum relative humidity of 90% with no condensation on the surface, and altitude not exceeding 2000m (if exceeding this, the requirements of GB/T16935.1-2023 must be met). These conditions ensure the safe and reliable operation of battery racks in most climates.

General Technical Requirements

Chapter 5 specifies general requirements for battery racks, including seven aspects: general requirements, battery rack connectors, wiring harnesses, grounding, clearance and creepage distances, insulation resistance, and dielectric strength.

General requirements include: limit guide function, anti-misplugging capability, electrical communication connection function with the charger, in-place status detection function, drainage function, automatic dust cover function, and safe transfer and transportation carrying capacity. These functional requirements ensure the safety, reliability and efficiency of the battery swap process.

Connector requirements clearly stipulate that they should comply with Chapter 7 of GB/T32879-2025, including electrical connectors and liquid connectors, providing a standardized interface for battery swap connections.

Wiring harness requirements include low-voltage wiring harnesses complying with QC/T29106-2014, power line pressure resistance and flame retardant and fire resistance complying with GB/T19666-2019, as well as independent bundling and isolation of power lines and low-voltage lines, and anti-interference measures for signal lines.

Grounding requirements stipulate that the connection impedance of the outer frame, electrical components, and connector metal casings must not exceed 0.1Ω, the diameter of the grounding bolt must be no less than 8mm, and grounding markings must be provided to ensure personnel safety and equipment protection.

Interchangeability Requirements and Structural Types

Core Interchangeability Requirements

Chapter 6 first proposed interchangeability requirements for battery box racks: battery box racks of the same type must be interchangeable; electrical connector interface signal definitions must be consistent; the cooling medium for liquid connectors must be 50% ethylene glycol and 50% water; and the load-bearing surface of commercial vehicle battery box racks must be flat. These requirements lay the foundation for the large-scale and networked development of battery swapping facilities.

Structural type standardization

The standard specifies the battery box frame structure types of commercial vehicles and passenger vehicles in detail through 8 appendices:

This standardized structural design not only ensures uniformity of basic interfaces but also provides room for technological innovation among different companies.

Mechanical Requirements and Test Verification

Mechanical Performance Indicators

Chapter 8 specifies the mechanical requirements for battery box racks for commercial and passenger vehicles: the clearance between the guide mechanism and the battery box must not exceed 5mm; high-strength bolt connections must comply with GB/T1231 requirements; after mechanical impact testing, the appearance must be free of cracks, connectors must not loosen or deform, and insulation resistance must meet requirements.

Test Method System

Chapter 9 establishes a comprehensive test method system, including general tests, connector tests, wiring harness tests, grounding tests, clearance and creepage distance tests, insulation resistance tests, dielectric strength tests, interchangeability tests, structural type tests, and mechanical impact tests.

The mechanical shock test has different requirements for commercial vehicles (vertical acceleration 1g) and passenger vehicles (horizontal acceleration 0.3g + vertical acceleration 0.15g), reflecting the actual needs of vehicle model differentiation.

Inspection Rules and Quality Assurance

Chapter 10 stipulates two types of inspections: type inspection and factory inspection, and clarifies the inspection items and qualification criteria. Type inspection is aimed at situations such as new product finalization, major process changes, and resumption of production, while factory inspection ensures the quality consistency of each product.

Inspection items include 10 categories: general test, connector test, wiring harness test, grounding test, electrical safety test, interchangeability test, structural type test and mechanical shock test, forming a complete quality verification system.

Labeling, Packaging, Transportation, and Storage Requirements

Chapter 11 specifies labeling requirements for battery boxes and racks (including safety warning labels and product nameplates), packaging and transportation requirements (rainproof, handle with care), and storage requirements (connector protection, rain-free and corrosion-free location). These requirements ensure that product quality is maintained throughout the entire product lifecycle.

Standard Implementation Recommendations and Application Guidance

Implementation Recommendations for Design and Manufacturing

Manufacturers should strictly adhere to the requirements of the standard when designing and manufacturing their products, paying particular attention to achieving interchangeability. It is recommended to establish a standardized module library to improve the versatility and interchangeability of components. When designing structures, refer to the structural types in the appendix to ensure that interface dimensions and tolerances meet standard requirements.

Implementation Recommendations for Testing and Certification

Testing organizations should establish comprehensive testing capabilities in accordance with the test methods in Chapter 9, particularly for key items such as mechanical impact testing, insulation resistance testing, and dielectric strength testing. It is recommended to develop special testing tooling and equipment to improve testing efficiency and accuracy.

Implementation recommendations for the use and maintenance link

Operating units should select and maintain equipment in accordance with standard requirements, and regularly check key indicators such as grounding reliability, connector status, and insulation performance. Connectors should be well protected during storage to prevent environmental factors from damaging the equipment.

Recommendations for standardization development

It is recommended that industry organizations carry out unified certification work based on this standard to promote the interconnection and interoperability of battery swapping facilities. At the same time, continue to track technological development, initiate standard revision work in a timely manner, and maintain the advancement and applicability of the standard.

The implementation of GB/T 33341-2025 will greatly promote the standardized development of battery swapping technology for electric vehicles in my country, provide technical support for the large-scale promotion and application of battery swapping models, help form a unified and open battery swapping service market, and promote the high-quality development of the new energy vehicle industry.