A novel steel concrete composite vessel (SCCV) technology has been developed as a cost-effective solution for stationary high-pressure gaseous hydrogen storage applications. SCCV technology is flexible to meet different pressure levels and storage capacities. SCCV has layered steel vessel wall and strategically placed vent holes to solve the safety concerns of hydrogen embrittlement (HE) problem for high-strength steel by design. A demonstration vessel capable of storing approximately 90 kg gaseous hydrogen at 6250 psi (43 MPa) has been designed and fabricated to demonstrate the SCCV technical feasibility. Hydrotest and cyclic hydrogen pressure test are used to validate both constructability and...