Like other electronic products, home batteries go through rigorous testing before installation and use at your home or business. These tests are critical to determining the quality and performance of batteries under particular environmental stresses, as well as confirming they meet mandated government safety requirements. In this article, we’ll review the most common testing and certifications for home batteries on the market today. Find out what solar + storage costs in your area in 2023
Why is battery testing important?
Battery testing and certification is key to assuring both the quality and safety of home storage systems. A battery constantly has energy being cycled in and out of it, and that puts real strain on the chemical and mechanical systems that keep batteries functional and safe. Testing batteries and certifying them by internationally-recognized standards ensures you’re getting a high-quality product that will deliver when you need it most.
Common home battery testing & certification standards
While reviewing a home battery spec sheet, you’ll likely notice a bunch of acronyms and random numbers listed under safety and rating certifications – what do these mean? Below are some of the most common battery testing standards and certifications to look for when comparing home batteries.
UL: Underwriters Laboratories
One of the other most common acronyms you’ll see on a spec sheet related to battery certifications and testing is UL. This stands for Underwriters Laboratories, a global safety certification company based in the United States. They provide testing services and certifications for many different types of products, including electric appliances, industrial equipment, plastic materials, solar panels, and more.
UL 9540: Energy Storage Systems and Equipment
This certification is an overall certification for what UL calls “Energy Storage Systems” – ESS for short. A UL 9540 ESS has a UL 1973-certified battery pack (more details below), and a UL 1741-certified inverter (also more details below). It is designed to certify complete systems so you can be sure your battery setup is configured correctly and its parts all work in harmony.
UL 1741: Inverters, Converters, Controllers and Interconnection System Equipment for Use With Distributed Energy Resources
As we mentioned above, UL 1741 is an inverter-specific product safety standard. It lays out manufacturing and product testing requirements for inverters, with the goal of producing inverters that can more capably manage grid reliability functions and handle electric grid changes. Within the UL 1741 certification are several tests such as the anti-islanding test, which makes sure the inverter can disconnect from the grid when appropriate. This and several other testing protocols all attempt to ensure that inverters can operate during both normal and abnormal grid conditions.
UL 1973: Standard for Batteries for Use in Stationary, Vehicle Auxiliary Power and Light Electric Rail (LER) Applications
UL 1973 is the battery-specific version of UL 1741, in that it certifies the ability of a battery system to withstand normal and abnormal conditions. It specifically does not evaluate any performance or reliability measures of a battery.
UL 1642: Lithium Batteries
This standard by UL is a lithium battery-specific testing standard, and it tests the risk of fires and explosions (both very, very rare in batteries – partly due to standards like these!).
UL 2054: Household and Commercial batteries
UL 2054 is a general battery safety standard by UL. It contains 18 separate tests that products need to pass, including seven electrical tests, four mechanical tests, and even a fire exposure test. Specifically for lithium batteries, this standard defers any component cell level testing to UL 1642, mentioned above.
UL 62133: Safety Requirements for Portable Sealed Secondary Cells
UL 62133 is the Underwriters Laboratory version of IEC 62133, a globally-recognized battery safety standard by the International Electrochemical Commission (IEC for short). The IEC has many more solar panel certifications than battery certifications, but for many years, IEC 62133 was one of the most important battery standards out there. UL 62133 is essentially the same thing, just from a different company. It’s been suggested that UL 62133 may replace both UL 1642 and UL 2054 at some point, but we haven’t gotten there quite yet.
Find high-quality solar equipment on EnergySage
Are you shopping for solar and storage equipment that meets the above certifications and more? Head over to the EnergySage Buyer’s Guide where you can compare different types of equipment based on efficiencies, warranties, and more. On each product page, we’ve listed the passed tests and certifications for each battery so that you don’t have to dig through spec sheets! Once you’re ready to see offers from local installers, sign up on the EnergySage Marketplace to receive free, online solar quotes from local installers.