Rocket Lab Corporation (NASDAQ: RKLB), based in Long Beach, California, said on Sept. 8, 2026, that it has released IMM Apex, a solar cell for space applications that eliminates the use of germanium substrates. The company said the cell has a beginning-of-life solar conversion efficiency of 31.5% and reduces cell mass by 40% compared with conventional multi-junction solar cells. IMM Apex is designed as a drop-in replacement for existing solar cell products, allowing integration into current systems without retooling, and Rocket Lab said optimized manufacturing processes enable production in multi-100-kilowatt volumes.
The product addresses supply chain constraints and rising material costs associated with germanium, which Rocket Lab described as a critical mineral used in conventional space solar cells produced over the past three decades. The company said IMM Apex underwent more than a decade of testing and qualification and is available now. Brad Clevenger, President of Rocket Lab USA, said, "IMM Apex delivers exceptional performance while addressing real-world challenges like rising material costs and supply chain constraints."
The release builds on Rocket Lab’s earlier IMM cell technology, which powered NASA’s Ingenuity Mars Helicopter and has been used in satellites for more than a decade. More than 1,100 satellites currently in orbit use Rocket Lab solar products, and the company has supplied space-grade solar technology to programs including the James Webb Space Telescope and NASA’s Artemis lunar explorations. Rocket Lab provides launch services, spacecraft, payloads and satellite components for commercial, government and national security markets; its Electron rocket serves the orbital small rocket market, while its Neutron launch vehicle is in development.
