Participated · Series B · Oct 2021

H2, Inc. is an industry-leading vanadium flow battery (VFB) developer and manufacturer based in Seoul, South Korea. The company produces the EnerFLOW 500 series for 4-hour applications, the EnerFLOW 600 series for 8+ hour applications (incorporating its HYPERSTRUCTURE technology), and UL-certified 5000-series VFB stacks. H2 raised $16 million in bridge funding finalized in the second half of 2024, bringing total accumulated funding to $77 million. Proceeds will be used primarily to construct the K2 Plant, which will expand manufacturing capacity to 1.2 GWh per annum and is scheduled to begin operations in 2026. The K2 Plant will triple the current K1 Plant capacity (330 MWh/year) and support mass production of H2's flagship products. The company has secured land for the K2 Plant and plans first deployment of EnerFLOW 640 units in Spain's 8.8 MWh VFB project in mid-2025. H2 develops and manufactures flow battery systems and cell stacks, including its container-type EnerFLOW430 (270 kWh) and cabinet-type EnerFLOW330 (50 kWh). EnerFLOW430 uses proprietary ‘FLEXMODULE’ technology to enable duration options from 4 to 10 hours in a standardized modular product. The company recently secured UL 1973 certification for its cell stack model 5266, a key step toward overseas market entry. In late 2020 an EnerFLOW430-based 1.1 MWh system was commissioned at a Korea East-West Power (EWP) facility in Ulsan and has operated under the REC scheme; it is described as the only commercially operating non-lithium battery installation running under REC in Korea. H2 plans to use new capital to expand manufacturing capacity and automation, targeting a 330 MWh production capacity in the first phase of its near-term expansion. The company is led by Founder and CEO Dr. Shin Han and intends to expand into overseas markets such as the US and other regions.