Light electric vehicles, especially e-bikes, are gaining immense popularity. As more people hop onto the ebikes, there’s a growing concern about their safety. The main concern is the lithium-ion batteries that power these bikes. They offer impressive performance, but there’s a looming fear about their potential to catch fire.
To address these concerns, the UL 2271 standard came into the picture. Batteries that earn this certification undergo rigorous testing and prove their mettle against a series of tough challenges. For consumers, this means one thing: peace of mind. Knowing that the battery propelling you forward has met strict safety standards makes an immense difference.
In this article, we’ll get into the details of the UL 2271 standard, the safety tests a battery goes into, and how this UL 2271 battery certification will elevate the safety of Maxfoot bikes.
What is UL 2271 Certification?
Underwriters Laboratories (UL) is a global safety certification organization based in Northbrook, Illinois. It was founded in 1894 as the Underwriters Electrical Bureau and later became widely recognized as Underwriters Laboratories. With a presence in 46 countries, UL has been at the forefront of setting safety standards for numerous electrical products. Products certified by UL proudly display their unique logo.
In 2013, UL introduced the UL2271 standard. It was aimed at batteries used in light electric vehicles i.e. e-scooters, ebikes, wheelchairs, golf cars, lawnmowers, etc. This standard was the result of collaborative efforts from a technical committee comprising representatives from organizations like LG Chemical, Du Pont, NASA, Ford, General Motors, the US Army, and Transport Canada, among others. The standard was revised in 2018, and a second was introduced, which further refined the safety criteria.
UL2271 certification evaluates the entirety of a battery, from its individual components to its overall construction. Firstly, it tests the battery enclosure's resistance to factors like impact, heat, flame, and water. Then, it ensures the battery’s wiring is properly wiring designed to avoid issues strain, and unintentional shorting. Finally, there are multiple mechanical tests to check its physical endurance.
For a battery to earn the UL2271 certification, it must successfully pass all the tests (listed in the section) without exploding, catching fire, leaking, presenting an electric shock risk, or losing any protective controls.
UL2271 Standard: Safety, Labelling, and Transportation Requirements
The UL 2271 standard is a comprehensive 67-page document copyrighted by Underwriters Laboratories. It needs to be purchased from UL. However, for the sake of clarity and understanding, we can categorize the contents of this standard into three primary sections: safety tests, labeling, and transportation.
Safety Tests Required for UL 2271 Certification
To ensure the highest standards of safety, batteries seeking UL 2271 certification are subjected to a comprehensive set of tests.
The first category focuses on the battery’s electrical integrity. Tests in this group include overcharge, short circuit, overdischarge, and isolation resistance. These tests make sure that the battery can handle various electrical stressors without malfunctioning.
Here’s a detail of those tests, what and how they evaluate battery,
Assesses the battery's resilience to overcharge due to a single fault in the charging control circuitry.
Evaluates the battery's ability to withstand a short circuit. A fully charged battery is short-circuited by connecting its terminals with a resistance of ≤ 20 m2.
Tests the battery's endurance against over-discharge under a protection circuitry fault. The battery is subjected to a constant discharging current as specified by the manufacturer.
Isolation Resistance Test
Determines the insulation's capability to isolate hazardous voltage circuits from the battery's accessible conductive parts and checks for non-hygroscopic insulation.
Next, the battery undergoes a series of mechanical evaluations. These tests, which include vibration, shock, crush, and drop assessments, determine the battery's resilience to physical stress and potential damage.
Vibration Endurance Test
Assesses the battery's durability against vibrations typical in an LEV. The test follows the ISO 12405-1 standard or a manufacturer-specified profile. The battery undergoes random vibrations along three perpendicular axes.
Determines if the battery can withstand mechanical shocks common in LEV usage. Shocks are applied in all spatial directions, depending on the battery shape.
Evaluates hazards when the battery is accidentally dropped during user handling. The battery is dropped thrice from a height of 1.0 m onto a concrete surface.
Assesses the battery's resilience to crushing forces, simulating vehicle accidents. This is done for on-road LEVs. The battery is crushed between surfaces with specific configurations.
Lastly, the battery is exposed to different environmental conditions. Water exposure tests and thermal cycling evaluations are conducted to ascertain the battery's performance and durability under varying environmental conditions.
Water Exposure Test
Tests the battery’s ability to withstand water exposure during activities like cleaning or outdoor storage. The test follows the IEC 60529 standard, for protection against water (IPX3) or higher ratings specified by the manufacturer.
Thermal Cycling Test
Evaluates the battery’s endurance against rapid temperature changes, such as moving from a cold environment to a heated one.
Note: Apart from these some general tests are also performed, however, since our main goal was to provide just quick insights, we have mentioned the tests that were purely relevant for ebike batteries.
Labelling Requirement for UL 2271
To achieve certification under the UL 2271 standard, a battery must prominently display the following details on its label:
Manufacturer Details: Name and address.
Manufacture Date: The date when the battery was produced.
Serial Number: Unique identifier for each battery.
- Type of battery
- Maximum charge current
- Maximum discharge current
- Maximum charge voltage
- Minimum discharge voltage
- Cycle of life
- Calendar life
Warranty: Duration of the warranty period.
Origin: Country where the battery was manufactured.
Certification Logos: The UL logo to signify certification.
Additionally, the UL2271 standard mandates the inclusion of a temperature warning on the battery label. It should caution against exposing the battery to temperatures exceeding 140°F (60°C) or dropping below -4°F (-20°C).
Furthermore, the UL 2271 standard encompasses a Label Performance Test. This test is designed to assess the durability and adherence of a label that hasn't undergone prior evaluation. The procedure involves a water rubbing test, where the label is manually rubbed for 15 seconds using a cloth drenched in water. Subsequently, the label is rubbed for another 15 seconds with a cloth soaked in petroleum spirit.
Transportation Requirements of UL 2271
Lithium-ion batteries for Light Electric Vehicles (LEVs) must follow transportation guidelines set by the United Nations (UN), International Maritime Organization (IMO), and International Air Transport Association (IATA). Key requirements include:
- Proper shipping labels on batteries.
- Use of approved containers for transportation
Why Do You Need To Buy E-Bikes With UL Certified Batteries?
In the US, UL 2271 is not a mandatory certification for ebikes but for e-scooter. However, we suggest that ebike business should prioritize it as they present a multitude of advantages to the potential ebike riders:
UL 2271 certification means batteries undergo thorough testing. This minimizes the chance of battery-related accidents. Riders benefit from a safer journey, while businesses face fewer recalls and potential liabilities.
When riders are aware that their ebike battery adheres to the strict UL 2271 standards, they can ride with confidence.
The certification assesses the battery's resilience under various scenarios, which can lead to extended battery longevity. So, riders benefit from prolonged battery performance, and businesses gain commendations for product durability.
UL 2271-certified batteries comply with global transportation guidelines. This eases the shipping process for businesses, and riders can expect timely deliveries without regulatory delays.
What UL2271 Certification Means for Businesses?
The benefits of this certification are mutual as businesses can equally benefit from it in the long run. For instance, when businesses sell UL-certified products, they are actually emphasizing their commitment to safety and quality.
When businesses invest in e-bikes for commercial use, they naturally choose models that prioritize safety. This certification amplifies a business's image as a reliable partner.
In the e-bike market, trust is also crucial. The UL2271 certification puts a stamp seal on this trust. Consumers recognize the certification as a symbol of safety and quality.
UL Certification Stages: How Business Acquire It?
We have covered the safety test requirements. But you should also be aware of how ebike businesses get this certification; and the steps and stages they have to undergo for getting certified.
- Application Submission: Manufacturers submit an application to UL-certified labs for evaluation, mentioning all battery specs and intended use of the battery
- Preliminary Review:UL experts review the application information. An initial series of tests are conducted to gauge the battery's alignment with established safety standards.
- In-depth Sample Testing: Samples (18 to 20) sent by manufacturers undergo a rigorous testing regimen that we discussed earlier.
- Manufacturing FacilityEvaluation: The UL team also visits the production facility to verify safety and quality adherence.
- Sustained Compliance: After certification, manufacturers have to consistently meet UL standards to keep the certification.
UL2271 and Maxfoot's Commitment
In recent months, we have diligently pursued the UL 2271 certification. Today, we are thrilled to share that the upcoming Maxfoot ebike model/s will feature UL-certified batteries. This is our dedication to delivering safer, more durable, and eco-conscious ebikes. Prepare for the next generation of secure ebikes!