(Invited) Electrochemistry’s Role in Current and Future Environmental Control and Life Support Systems

Abstract

The current Environmental Control and Life Support System (ECLSS) Oxygen Generation System (OGS) onboard the International Space Station (ISS) utilizes electrochemistry in order to generate oxygen consumed by the crew. The OGS consists of two major components, the Oxygen Generation Assembly (OGA) and the Carbon Dioxide Reduction System (CDRS). The OGA electrolyzes water to produce oxygen (O2) and hydrogen (H2). Oxygen is released into the cabin for crew consumption, and the hydrogen byproduct is recycled back to the CDRS, which utilizes the H2 to generate the water for OGA from metabolic carbon dioxide (CO2). As exploration of our solar system progresses, development of technologies to limit earth reliance is vital. The current state of the art (SOA) O2 recovery system is capable of recovering approximately 50% of O2 from metabolic CO2. For future long duration missions, the target recovery goal is 90% with a minimum of 75% recovery is required. To help reach this goal, several investigations are underway that involve electrochemical processes. These processes are utilized for several different applications, such as electrodeposition of O2 recovery fouled catalyst, the development of an advanced microfluidic electrochemical reactor, and a hydrogen separator that utilizes electrochemical techniques to recover H2 from a methane post processor. These electrochemical approaches address different issues that future ECLSS OGSs face but share one common end goal, maximizing O2 recovery for long duration missions. Here, we will discuss the electrochemical aspects of both current and future ECLS Systems and how the development of these technologies may aide in future long duration life support systems.