ESS Partners with Alsym Energy to Deliver 8.5 GWh of Non-Lithium Battery Energy Storage Solutions
ESS and Alsym Energy will supply 8.5 GWh of sodium-ion batteries to expand ESS’s storage portfolio beyond long-duration systems, targeting short- and medium-duration applications with safer, lower-cost alternatives to lithium-ion.
ESS Tech and Alsym Energy have agreed to integrate 8.5 GWh of sodium-ion cells and modules into ESS’s offerings, marking the company’s entry into short- and medium-duration battery energy storage markets traditionally dominated by lithium-ion systems. The collaboration leverages Alsym’s non-flammable sodium-ion technology, which eliminates thermal runaway risks and reduces reliance on complex HVAC systems, lowering total cost of ownership for customers. ESS’s existing Energy Base® iron flow platform serves long-duration storage needs, while the new sodium-ion solution addresses high-power, fast-cycling applications where rapid response is critical. Together, the two technologies aim to provide a unified, non-lithium storage platform for utilities, independent power producers, data centers, and commercial customers seeking safer, more sustainable alternatives.
Alsym Energy’s sodium-ion Na-Series batteries use non-foreign sourced materials and a proprietary AI-driven development platform to achieve high round-trip efficiency and fast charge-discharge cycles without requiring extensive fire suppression infrastructure. The technology’s thermal stability and wide operating temperature range simplify deployment, reducing system complexity and operational costs compared to lithium-ion alternatives. ESS will integrate these modules into its grid-scale storage systems, expanding its addressable market to include applications such as renewable energy firming and daily energy shifting. The partnership underscores a shift toward supply-secure, cost-effective storage solutions that prioritize safety and scalability across diverse use cases.
ESS CEO Drew Buckley highlighted the complementary nature of sodium-ion and iron flow technologies, noting that Alsym’s Na-Series excels in short- to medium-duration applications requiring high power and rapid cycling, while ESS’s Energy Base® platform remains optimal for 8–24 hour long-duration storage. Randall Selesky, ESS Chief Commercial Officer, emphasized the strategic milestone of offering a full-spectrum, non-lithium storage portfolio that meets customer needs without compromising performance or economics. The combined platform targets utilities, IPPs, data centers, and commercial customers seeking American-made, flexible solutions for grid stability and renewable energy integration.
Alsym Energy CEO Mukesh Chatter emphasized the urgency of scaling alternatives to lithium-ion to meet growing energy storage demand, positioning the partnership as a response to industry needs for high-performance, inherently safe, and supply-resilient solutions. The collaboration integrates Alsym’s Na-Series with ESS’s systems expertise to deliver grid-scale storage that maximizes renewable energy value while addressing safety and cost challenges. The combined offering aims to support a broad range of applications, from data centers to utility grids, with a focus on future-proof, sustainable energy storage infrastructure.