SAX Power

About SAX Power

SAX Power GmbH, founded in 2019 by Lei Shen and headquartered in Erbach, Germany, operates as a manufacturer of advanced battery storage systems. The company's technology originated from a partnership with Deutsche Bahn, where it developed control systems for converter stations in the German rail power grid. SAX Power has since applied this expertise to the broader energy storage market, targeting homeowners and businesses across Europe looking to increase energy independence.

The company generates revenue through the direct sale of its energy storage systems, which are suitable for both new photovoltaic installations and retrofitting existing ones. The business model is centered on the sale of its core products, the SAX Power Home series, with potential for additional revenue from app-based services for remote monitoring and future updates. A funding round in October 2025, led by Yotta Capital Partners, raised EUR 10 million to scale production and expand its product range.

SAX Power's core product is a lithium-iron-phosphate (LFP) battery storage system featuring a patented technology that integrates the inverter function directly into the battery. This design eliminates the need for a separate, external inverter, which can reduce the system's size and weight by approximately 30%. Key features include a digital cell control system that converts DC power from sources like solar panels directly into AC power, achieving a high efficiency of 99%. The technology employs a unique cell balancing method that extends battery lifespan by up to 40% and allows for modular expansion; for instance, the SAX Power Home system can be expanded by connecting up to three modules. Safety is a significant aspect of the design, which uses cobalt-free cells and incorporates a rapid cell shutdown mechanism that can switch off the unit in milliseconds.