Glass seals join electrolysis stacks with secure hermetic bonds
During production of the SOXE stack, the glass powder is melted to form a bond between the ceramic electrolyte and metal interconnect of the cell. The sealing glass is formulated to match the exact coefficient of thermal expansion of the metals and ceramics, creating an uncompromising hermetic seal that remains stable even when temperatures shift. Furthermore, the interconnectors of the cells that are switched in series as part of a stack, are electrically insulated by the alkaline-free glass, even at high temperatures.
“The extreme temperatures and high forces present a special challenge for the MOXIE,” explains Dr. Jens Suffner, Technical Sales Manager at SCHOTT Electronic Packaging. “Many types of glass turn soft and elastic at temperatures of 500 °C and higher.” To prevent this, SCHOTT uses special sealing glasses with defined crystalline phases. This keeps the glass seal gas-tight and in place with sufficient strength, even under the harsh conditions present on Mars.
With MOXIE being successful, it might revolutionize human exploration on Mars. The breathable air needed for a manned space mission could be directly generated on site. The created oxygen will also be used as the oxidant for the production of rocket fuel. This would solve an essential part of the challenge for enabling a return flight. So far, the road to the red planet has been viewed as a one-way street.