Electrochemical Cell Mimics Battery to Capture CO2 More Efficiently

Researchers in Delaware, collaborating with the Israeli company Ripair, have developed an electrochemical cell that functions similarly to a battery to capture carbon dioxide (CO2) directly from the air. This Direct Air Capture (DAC) technology aims to reduce the cost and energy required for CO2 separation, a significant challenge due to the gas's low concentration in the atmosphere.

Unlike conventional DAC methods that use heat to release captured CO2, this new approach alters the electrical state of the cell. Nickel hydroxide electrodes and an ion-conducting membrane are at the core of the system. By changing the electrical charge, the chemistry shifts, moving the gas from one part of the system to another without the need for extensive heating and cooling cycles.

A prototype cell measuring 25 square centimeters operated for approximately 5,000 hours, exceeding six months of continuous use. The researchers also demonstrated a larger array of nine cells, each 300 square centimeters. Durability is a critical factor in DAC technology, as materials can degrade quickly under constant operation.

The economic advantage lies in reduced energy consumption. Traditional DAC systems rely heavily on heat, which is costly, especially when aiming to remove millions of tons of CO2. The electrochemical method replaces some of that heat-dependent energy with electricity, allowing for more direct integration with renewable energy sources.

Ripair, a company from Zichron Yaakov, Israel, is a key partner in this research, with four of its personnel listed as co-authors on the study. For startups in this field, demonstrating long-term operational reliability is crucial for scaling up from laboratory to industrial production.

Despite this advancement, DAC technology is still far from widespread industrial application. Current facilities are small relative to global emissions, and the cost per ton of captured CO2 remains high. Leading companies aim for costs in the hundreds of dollars per ton, with a goal of reducing it further. The new electrochemical system must prove its effectiveness at an industrial scale, handling real-world airflows, maintenance, and equipment costs. If successful, this battery-like cell could significantly lower a major expense in the carbon capture economy.