Polymers for water and energy systems
Clean water and energy are inextricably linked in a symbiotic relationship whereby clean water is needed to produce energy and energy is needed to produce clean water. Access to reliable energy and clean water have been identified as two of the top 10 problems facing humanity in the coming decades. As the effects of climate change and population growth contribute to the rising global demand for water, current water supplies will continue to be stressed. The growing need for access to clean water has led to an increased interest in nontraditional water sources such as municipal wastewater, brackish groundwater, seawater, and produced water from the oil and gas industry. Unlocking the potential of these water sources can lead to water reuse in agricultural, industrial, and energy production applications, which in turn can decrease the stresses placed on potable water sources. Additionally, many of these wastewater streams offer a unique opportunity for resource recovery, such as Li⁺ extraction from produced water that can in turn be used to produce the batteries needed to facilitate the transition to electrification of the economy. As the world transitions from fossil-fuels based energy generation and transportation to utilizing intermittent renewable energy technology such as solar and wind, there is a growing need for improved energy storage. Although no one technology can completely solve all the issues associated with this transition, lithium-ion batteries represent a promising technology that can be utilized for both grid-level storage and as the main component of electric vehicles. While state-of- the-art lithium-ion batteries have experienced significant technological improvements that have led to higher energy density, lower costs, and high cycle life, significant improvements are still necessary for a fully electric future. The promise of a highly energy dense, high cycle life, safe, and fast charging lithium-ion battery is theoretically possible if the anode material of the battery is replaced with metallic lithium, creating a solid-state battery. This change in anode material necessitates the development of an electrolyte material with different physical properties than the currently utilized small molecules electrolytes in today’s lithium-ion batteries. Polymeric materials have shown promise as potential electrolyte material in these solid-state batteries, though there is still significant work needed to understand the structure-property relationships in these materials to better optimize their Li⁺ conduction.