Battery Certifications Explained for Solar Installers

For solar installers, battery selection is not only about capacity and price. Battery certifications also affect system safety, approvals, insurance, and long-term project reliability.

This guide explains why battery certifications matter, what UL certification means, UL vs. CE differences, and the key lithium battery standards installers should know for solar energy storage systems.

Why Battery Certifications Matter for Solar Installers?

For commercial solar energy storage projects, battery certifications are often an important requirement during the project approval process. Compared with residential systems, commercial projects typically involve higher energy demands, stricter safety regulations, and more complex compliance requirements.

Certified lithium batteries for solar storage can help installers:

• Meet local electrical codes and energy storage system safety standards;
  
• Provide certification documents, test reports, and technical documentation required for project approval;
  
• Simplify the AHJ (Authority Having Jurisdiction) review process;
  
• Reduce the risk of project delays caused by non-compliant battery products.

For example, in some commercial battery storage projects, developers, engineering companies, or regulatory authorities may require battery systems to comply with safety standards such as UL and IEC certifications to ensure the system design, installation, and operation meet required safety guidelines.

Therefore, selecting certified batteries for solar energy storage not only improves system reliability but also helps solar installers complete commercial projects more smoothly, from approval to final installation.

Common Battery Certifications for Solar Installers

When selecting batteries, solar installers often ask: what are the common battery certifications? Different certifications cover different needs, and they are not interchangeable. Knowing these marks helps you decide whether a battery is suitable for residential or commercial energy storage projects.

The battery certifications installers see most often include:

1. UL1973

A safety certification for stationary and residential energy storage lithium batteries—and one of the most common requirements in North American projects. Many installers prefer UL certified lithium batteries, especially UL1973-certified home batteries.

For example, PowMr’s 100Ah 51.2V Stackable Lithium Battery (SKU: POW-LIO48100-3UL) is designed for residential energy storage with UL1973 certification, making it a practical option for installers specifying certified home battery systems.

2. UN38.3
Focused on lithium battery transport safety. It is not the same as a home installation safety certification. Having UN38.3 only means the battery meets shipping requirements—it does not replace UL1973.

3. IEC 62619
An international standard often used for industrial and commercial stationary storage batteries. It appears frequently in export and commercial project specs.

4. CE

CE compliance is a conformity mark for entering the EU market. It matters for European projects, but CE is not the same as UL, and the two cannot replace each other.

5. UL9540 / UL9540A
These relate more to complete energy storage systems than to single battery modules. They are not a day-to-day substitute when choosing a battery, but they may come up in larger energy storage system(ESS) projects.

For solar installers, match the certification to the job: prioritize UL1973 for North American residential storage, UN38.3 for shipping, CE for Europe, and IEC 62619 for many commercial projects. 

What Is UL Certification?

UL certification means a product has been tested to relevant safety standards from UL (Underwriters Laboratories) in the U.S. For solar installers and energy storage projects, it usually means the battery or electrical product has gone through third-party safety evaluation—not just a manufacturer’s self-declaration.

UL focuses on how safely a product performs in real use, including risks such as electric shock, overheating, overcharge, and short circuit. For lithium batteries, a commonly referenced standard for residential and stationary storage is UL1973. So when customers ask whether a battery is among UL certified lithium batteries, installers should clarify: do they mean UL in general, or a specific storage standard such as UL1973?

Key UL Battery Standards for Solar Energy Storage

Do Batteries Need to Be UL Certified?

Not always. Lithium batteries do not need UL certification in every country or every use case. Whether it is required depends on the project market, installation type, and whether inspection, insurance, or tender requirements apply.

For solar installers and homeowners, the better question is not simply “Does this battery need UL?” but: Will this project require UL certified lithium batteries?

When UL is usually needed?

• North American residential or stationary storage projects, where installers, inspectors, and insurers often ask for UL1973
  
• Grid-tied or home backup systems that need permitting / inspection
  
• Bid documents, EPC specs, or distributor catalogs that explicitly require UL
  
• Customer contracts that call for third-party safety certified batteries

UL vs. CE: Key Differences Between Lithium Battery Certifications

When buying or installing a lithium battery, many people treat UL certification and CE compliance as the same thing. Both relate to safety and compliance, but they differ in nature, market focus, and legal meaning—and they cannot replace each other.

Key differences at a glance