ESS Tech, Inc. GWH

What this company does

The company designs and produces long-duration batteries predominantly using earth-abundant materials that it believes can be cycled over 20,000 times without capacity fade based on lab-scale results. Because the batteries are designed to operate using an electrolyte of primarily salt, iron and water, the company's products are environmentally sustainable and substantially recyclable or reusable. The company designs and builds this core technology, including battery stacks, electrolyte and electrolyte health management solutions, into a core power train that is then sold in its current product focus: the gigawatt-hour scale, fully configurable Energy Base and core power trains that can be assembled at the customer site into complete storage solutions. When comparing products on a lifetime levelized cost of storage (LCOS) basis, which is the total cost of the investment in an electricity storage technology divided by its cumulative delivered electricity, the company expects its batteries to be less expensive than lithium-ion alternatives for storage durations greater than eight hours.

Written from the business description in ESS Tech, Inc.'s annual report to the U.S. Securities and Exchange Commission, filed 5 March 2026. Every sentence was checked against that document before publication.