Which Laboratory Can Process Lithium Battery EN 50604-1 Certification?

The European Committee for Standardization (CEN) released the new edition of the standard for Electrically Power Assisted Cycles (EPAC), EN 15194:2017+A1:2023, on August 23, 2023, which will become mandatory starting August 23, 2025. The battery testing requirements in the new standard have removed the reference to the EN 62133 standard, establishing the new EN 50604-1 as the sole criterion for the safety requirements of EPAC battery usage. EN 50604-1 is a safety requirement standard applicable to secondary lithium batteries for Light Electric Vehicles (LEVs).

Product Scope

EN 50604-1 Scope of Application:

Removable (including built-in) lithium-ion battery (pack) systems intended for LEVs within the following classifications:

• Voltage Class A: Maximum operating voltage ≤ 30V a.c. (rms) / ≤ 60V d.c.

• Voltage Class B: Maximum voltage between 60V d.c. and 200V d.c.

According to the standard requirements, the Battery Management System (BMS) should be able to protect the battery system from damage, monitor and extend its service life, maintain its functional state, and evaluate and control the cells, cell blocks, and battery to ensure they operate under the conditions specified by the cell manufacturer.

The EN 50604-1 standard primarily evaluates the product from 5 perspectives: physical safety, environmental tolerance, scenario simulation, electrical safety, and system protection. The specific test items and requirements are as follows:

Mechanical Tests

• Vibration Test: By simulating the vibration conditions of the vehicle during driving, this tests the performance of the battery in a vibrating environment. It requires that within the specified frequency range, amplitude, and vibration duration, the battery should not experience mechanical damage, loose electrical connections, or internal short circuits, and all performance indicators must comply with specified limits.

• Mechanical Shock Test: Simulates the shocks a battery might suffer during transportation, installation, or use, such as collisions and drops. The battery must maintain structural integrity without rupture or leakage under shocks of varying directions and intensities, and its electrical performance must still meet requirements after the shock.

• Drop Test: The battery is freely dropped from a specific height onto a designated surface to check for changes to its casing, internal structure, and electrical performance. It typically requires that after multiple drop tests, the battery shows no obvious external damage, no internal cell displacement or short circuits, and can still charge and discharge normally.

• Test for Thermoplastic Materials Exposed to Sunlight: Evaluates the performance changes of thermoplastic components that may be exposed to sunlight under prolonged illumination and high temperatures. These materials are required not to exhibit deformation, embrittlement, fading, or other issues that could affect battery safety and performance after a certain period of light and heat exposure.

Climatic Tests

• Condensation (Dewing) Test: Simulates condensation phenomena on the battery under different temperature and humidity environments to check the battery's sealing and moisture-proof performance. After the test, there should be no moisture intrusion inside the battery, and the electrical insulation performance should meet requirements to prevent short circuits and corrosion caused by condensation.

• Thermal Shock Cycling Test: Subjects the battery to rapid cycles between high and low temperatures to test its adaptability and reliability under extreme temperature variations. After the specified number of thermal shock cycles, the battery must maintain good performance, with indicators such as capacity retention, internal resistance changes, and charge/discharge efficiency remaining within specified ranges.

Simulation Tests

• Crush Test: Simulates situations where the battery is involved in a vehicle accident or subjected to external crushing forces to test its crush resistance. When subjected to the specified crushing force, the battery must not catch fire, explode, or leak, and the deformation of the casing should not affect its normal use and safety.

• Water Immersion Test: The battery is immersed in water at a certain depth for a specified time to check its waterproof performance and electrical safety. After immersion, the battery should function normally without short circuits or electrical leakage, and parameters such as insulation resistance should meet requirements.

• Over-temperature Condition Test: Places the battery in a high-temperature environment exceeding its normal operating temperature range to evaluate its performance and safety under over-temperature conditions. After the test, the battery should not experience dangerous situations like thermal runaway, fire, or explosion, and changes in various performance indicators should be within allowable limits.

• Low-temperature Condition Test: Places the battery in a low-temperature environment to test its charge/discharge performance and starting performance under cold conditions. The battery is required to still output a certain current at low temperatures to meet the vehicle's starting and operating needs. Furthermore, after low-temperature cycle testing, the battery's capacity degradation should not exceed the specified value.

Electrical Tests

• Short Circuit Test: Directly shorts the positive and negative terminals of the battery to test the current and voltage changes, as well as the response time and effectiveness of the protection device under short-circuit conditions. During the test, the battery should promptly trigger the short-circuit protection device to cut off the circuit, preventing dangers like overheating and fire caused by excessive current. Once the short circuit is removed, the battery should resume normal operation or meet relevant safety requirements.

System Function Tests

• Overcharge Protection Test: Overcharges the battery to verify the overcharge protection function of the Battery Management System (BMS). When the charging voltage exceeds the set overcharge protection threshold, the protection device should act immediately to stop charging, preventing the battery from being damaged or causing a safety accident due to overcharging.

• Over-discharge Protection Test: Discharges the battery excessively below the set over-discharge voltage limit to check the BMS's over-discharge protection function. The protection must take effect in a timely manner to prevent deep discharge, thereby protecting the battery's lifespan and safety.

• Thermal Control / Cooling Failure Test: Simulates the failure of the battery's thermal management system to monitor the battery's performance and safety in a high-temperature environment. Upon thermal control or cooling failure, the battery should be able to prevent thermal runaway through its own protection mechanisms, such as reducing the charge/discharge current or cutting off the circuit.

• Deep Discharge Protection Test: Verifies the protection capabilities of the BMS during deep discharge of the battery, ensuring the battery does not suffer irreversible damage that would affect its performance and lifespan due to excessive discharge.

Certification Process

1. Determine Requirements and Prepare: Clarify the applicable scope of the product, understand the standard requirements, and prepare relevant product documentation.

2. Product Design and Manufacturing: Design and manufacture the product according to the standard.

3. Product Testing: Send samples to a qualified laboratory for testing in accordance with the standard.

4. Prepare Documentation: Simultaneously prepare technical documents, such as product specifications.

5. Submit Application: Submit the application and documentation to the certification body.

6. Review and Evaluation: The certification body reviews the documents and test reports, which may include an on-site audit.

7. Rectification (if applicable): If the product does not meet the requirements, make rectifications and retest.

8. Obtain Certificate: Upon passing the review, the certificate is issued, and the product can carry the ce mark.