GB29743.2-2025
Motor vehicle coolant—Part 2: Electric vehicle coolant
机动车冷却液 第2部分：电动汽车冷却液
GB 29743.2-2025 is a current mandatory Chinese national standard for Motor vehicle coolant—Part 2: Electric vehicle coolant. It appears in the Electronics compliance cluster with a product safety focus and has an implementation date of Oct 1, 2025.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
This standard applies to the production, inspection, and use of electric vehicle coolants formulated with ethylene glycol as the antifreeze base. It is specifically designed for the power battery thermal management systems in battery electric vehicles (BEVs), fuel cell electric vehicles (FCEVs), and hybrid electric vehicles (HEVs) with independent thermal circuits and B-class voltage. It does not cover coolants for internal combustion engines, which are addressed in GB 29743.1.
Technical requirements
The standard classifies EV coolants into concentrates (EVC-I) and prediluted solutions (EVC-II) based on ethylene glycol formulations. It mandates general requirements for appearance, color, and odor, ensuring the fluid is a clear, transparent liquid without precipitates or irritating smells. For physicochemical properties, the standard specifies critical parameters including density, freezing point, boiling point, and pH levels. It also sets strict limits on electrical conductivity, chloride, sulfate, and borate content to prevent corrosion and electrical hazards in high-voltage EV systems. Manufacturers must ensure the coolant does not adversely affect automotive organic coatings. Regarding performance requirements, the standard outlines rigorous criteria for static and circulating corrosion protection across various metals like copper, brass, steel, and cast aluminum. It also dictates rubber material compatibility with EPDM and silicone rubbers, alongside requirements for foam tendency and thermal/storage stability.
Testing methods
The standard references several specialized testing procedures. Conductivity testing is detailed in Appendix A to ensure low electrical conductivity. Static corrosion tests (Appendix B) and circulating bench corrosion tests (Appendix C) evaluate the coolant's ability to protect metal components over extended periods. Rubber compatibility tests (Appendix D) measure changes in volume, hardness, and tensile strength of elastomer materials. Additionally, standard methods from SH/T and GB/T series are referenced for measuring density, freezing/boiling points, and foam characteristics.
FAQs
What products are regulated under GB 29743.2-2025?
It regulates electric vehicle coolants based on ethylene glycol, specifically for power battery thermal management systems in BEVs, FCEVs, and certain HEVs.
How does GB 29743.2 differ from GB 29743.1?
GB 29743.1 covers coolants for traditional internal combustion engine vehicles, whereas GB 29743.2 specifically addresses the unique requirements of EV coolants, including strict electrical conductivity limits.
What are the key performance tests required for EV coolants?
Key tests include static and circulating corrosion tests, rubber compatibility with EPDM and silicone, foam tendency, and high-temperature stability.
The summary above provides a high-level overview of GB 29743.2-2025. To ensure complete compliance for your EV thermal management products entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 29743.2-2025 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Product
- CCS
- R16
- ICS
- 03.220.20
- Competent department
- Ministry of Transport
- Technical committee
- National Technical Committee on Automobile Maintenance and Repair of Standardization Administration of China