Versatile Power-to-Water Battery for Energy Storage, Atmospheric Water Harvesting, and Humidity Control

Abstract

We present a novel power-to-water (P2W) battery that can store electricity as thermal energy and discharge it as a heat source for hygroscopic solution desorption. The battery can work in two scenarios: atmospheric water harvesting (AWH) and dehumidification. The involvement of high-grade energy and sophisticated design enables better sorption kinetics and storage density. A proof-of-concept prototype verified the feasibility and achieved a record-breaking water production rate of more than 10.2 g (L device h) −1 . Also, the battery can achieve a round-trip efficiency of 90% for AWH and 68% for dehumidification in large-scale storage. The inexpensive storage medium contributes to a very low cost per energy (∼20 $ kWh −1 ) which means that P2W batteries excel in short-and long-duration storage. The long-term transient performance studies demonstrate impressive competitiveness over the traditional AWH and vapor-compression dehumidification systems. P2W provides new directions for the development of versatile, scalable, repeatable, and sustainable energy storage systems.

Recyclable and Degradable Biomass-Based Water Vapor Sorbents for Efficient Atmospheric Water Harvesting

“…Advanced sorbents, such as zeolites, porous carbon, metal–organic frameworks (MOFs), − covalent organic frameworks (COFs), − polymers, − hygroscopic salts, and hybrid sorbents, − have been developed in recent years. In addition, the applications of water vapor sorbents have been extended much beyond freshwater production, including, but not limited to, heat transformation, − dehumidification, − and power generation. , As the need for SAWH sorbents grows, the production of sorbents is expected to increase sharply in the future. However, environmental concerns from sorbent preparation and disposal have been largely overlooked thus far.…”