依據歐盟施行的個人資料保護法，我們致力於保護您的個人資料並提供您對個人資料的掌握。
按一下「全部接受」，代表您允許我們置放 Cookie 來提升您在本網站上的使用體驗、協助我們分析網站效能和使用狀況，以及讓我們投放相關聯的行銷內容。您可以在下方管理 Cookie 設定。 按一下「確認」即代表您同意採用目前的設定。
blog
Technical Blogs
Markets
【EV Battery Safety & Coolant Selection】Key Takeaways from ECE-R100-2 Certification via Recent Electric Bus Fire Incidents
【EV Battery Safety & Coolant Selection】Key Takeaways from ECE-R100-2 Certification via Recent Electric Bus Fire Incidents
On June 16, 2025, reports of an "electric bus catching fire shortly after leaving the factory" rapidly sent ripples through the industry. While the specific cause is still under investigation, the incident serves as a stark reminder for the sector to remain vigilant regarding EV battery safety and thermal management mechanisms. In the current era of rapid electrification, thermal runaway has emerged as a risk that cannot be ignored. From structural engineering to material selection, every nuance can dictate the safety of both passengers and the vehicle. This is precisely why, since 2016, the European Union has mandated that all M1 (passenger cars) and N1 (light commercial vehicles) category electric vehicles must achieve ECE-R100-2 Revision 2 certification.
Coolants and ECE-R100-2 Rev 2 Safety Certification
ECE-R100-2 Revision 2 is a type-approval regulation established by the United Nations Economic Commission for Europe (UNECE) for electric vehicles and their high-voltage propulsion systems, specifically known as REESS (Rechargeable Energy Storage Systems). Since July 2016, this regulation has officially become a mandatory prerequisite for all battery electric vehicles (BEVs) seeking road-legal status in the European market.
Core Testing Requirements of ECE-R100-2 Rev 2 (9 Essential Tests)
The following tests are specifically designed for Battery Packs and Battery Management Systems (BMS) to ensure operational safety under both routine usage and extreme scenarios:
- Vibration Test: A sinusoidal sweep from 7–50 Hz for three hours to simulate real-world driving vibrations.
- Thermal Shock and Cycling: Alternating cycles between temperatures of +60°C and –40°C (repeated 5 times).
- Mechanical Shock: Simulates the acceleration/deceleration conditions typical of vehicle collisions.
- Mechanical Integrity (Crush): Subjecting the pack to compressive forces up to 10 tons (100 kN) to test structural endurance.
- Fire Resistance: Exposure to diesel fuel flames for ≥ 2 minutes (while 70 seconds at temperatures reaching 700°C is also common in international standards).
- External Short Circuit Protection: A controlled short circuit lasting over 1 hour to verify the effectiveness of protection mechanisms.
- Overcharge Protection: Continuous charging until the BMS triggers a disconnect, preventing short circuits or cell damage.
- Over-discharge Protection: Discharging to the predefined cutoff point to prevent electronic failure caused by deep discharge.
- Over-temperature Protection: Verification of temperature control during continuous high-current charging and discharging cycles.
Objectives and Regulatory Scope
Objective
To ensure that Lithium-ion battery packs remain stable and do not pose a hazard to the vehicle or its passengers under a wide range of extreme conditions—including vibration, thermal fluctuations, collisions, fire, short circuits, overcharging, over-discharging, and high-temperature environments.
Scope
The regulation is applicable to Category M1 (passenger vehicles with up to 9 seats) and Category N1 (commercial vehicles with a maximum gross weight of 3.5 tons). Since 2016, compliance has been mandatory for all new vehicle models; vehicles that fail to meet these standards are prohibited from legal operation on European roads.
Strategic Benefits
Upon achieving certification, battery pack manufacturers can independently apply for REESS type-approval. This decouples the battery from full-vehicle-level verification, significantly streamlining the process for global market distribution and supply chain integration.
The Intersection of Coolants and ECE-R100-2 Rev 2 Safety Certification
While coolants are not the primary subjects of ECE-R100-2 testing (which specifically targets REESS), they exert a profound indirect influence on certification compliance and overall test success rates. This is particularly evident in critical performance areas such as thermal management, thermal runaway mitigation, and the suppression of fire propagation.
| Category | Associated Tests | Coolant Requirements |
|---|---|---|
| Thermal Shock & Propagation (e.g., Thermal Cycling, High Temp, Heat Spread) |
|
|
| Flame & Thermal Runaway Propagation (Focus of Rev.3) |
|
|
| Dielectric Role in Short Circuit & Overcharge Tests |
|
|
| Cooling Circuit Reliability in Mechanical Tests |
|
|
Technical Selection Criteria for Coolants under ECE-R100-2 Rev 2:
| Item | Evaluation Metric | Recommended Values / Materials |
|---|---|---|
| Conductivity | Initial conductivity < 10⁻⁹ S/cm | PFPE, Novec, Galden HT, Fluorinert |
| Flash Point | No flash point or > 150°C | Water-based or fluorinated fluids |
| Chemical Stability | Non-reactive with Copper (Cu), Aluminum (Al), PC, PET | PFPE, 矽油 |
| Thermal Stability | Heat resistance > 150°C | PFPE Galden>Mineral Oil |
| Toxicity & Corrosivity | REACH/RoHS Compliance | PFPE (Generally non-toxic and non-corrosive) |
Conclusion: The Relationship Between Coolants and ECE-R100-2 Rev 2 Certification
| Property Type | Impact on Certification |
|---|---|
| Thermal Stability | Ensures success in high-temperature and thermal cycling tests. |
| Flame Resistance | Mitigates fire source propagation during thermal runaway events. |
| Dielectric Properties | Facilitates compliance with short-circuit and overcharge protection standards. |
| System Integrity | Guarantees no leakage occurs under vibration or collision stress. |
Latest Developments (ECE-R100-3 Rev 3)
Rev 3 has been in effect since September 2023, will become mandatory in 2025, and is set for full enforcement by 2030. It introduces even more stringent requirements, such as "Thermal Propagation" testing, specifically aimed at preventing the cascading spread of thermal runaway throughout the battery system.
For product technical documents (TDS, MSDS), sample requests, or business collaboration opportunities, please feel free to contact us:
Yamabala Industry Co., Ltd.
📍 Address: No. 11, Ln. 83, Longshou St., Taoyuan City 330, Taiwan
📞 Phone: +886-3-3789595
📠 Fax: +886-3-3701722
🌐 Website: http://yamabala.com
📧 Email: assistant@yamabala.com