Highly Safe, Durable, Adaptable, and Flexible Fuel Cell Using Gel/Sponge Composite Material

Abstract

With the rapid development of portable and wearable electronics, safety concerns over flexible energy devices are inevitable. Therefore, it is important to develop energy supplies that are safe for use. In this work, a highly safe, durable, adaptable, and flexible air‐breathing direct methanol fuel cell (DMFC) is successfully prepared by synthesizing and applying a new composite material with agar gel and wood sponge, that is, a gel/sponge composite. The gel/sponge composite has a high absorption rate, high cyclic performance, high methanol absorption capacity, high energy content, and high flexibility. Moreover, the gel/sponge composite with 1.5% agar gel retains approximately 90% of the methanol solution at a pressure of 29.4 kPa, and the areal energy density of the proposed DMFC approaches 13.7 mWh cm−2. Both the single‐cell and stack of DMFC with the new composite material successfully survive a series of destructive tests, including needle penetration, cutting, and compression. Therefore, it is successfully demonstrated that absorbent materials can greatly boost the safety, adaptability, flexibility, and energy density of air‐breathing DMFCs. Furthermore, this concept shows promise in improving the safety of other fuel cells by using absorbent materials to solidify their gaseous or liquid fuels.

Materials-Driven Soft Wearable Bioelectronics for Connected Healthcare

“…The gel/sponge composite-based flexible fuel cell stack could not only provide a 13.7 mWh/cm 2 power density but also retained the air-breathed methanol fuel under a 29.4 kPa pressure without fuel leakage. The fuel cell architecture was safe and could survive under numerous severe conditions including needle penetration, angle cutting, edge cutting, bending, and compression . To address the ethanol-crossover-induced catalyst poisoning, which has been the main obstacle for high-performance flexible fuel cells, it is essential to develop a highly active ORR electrocatalyst in the cathode that cannot be poisoned by fuels.…”

Materials, components, assembly and performance of flexible polymer electrolyte membrane fuel cell: A review

“…6a) reaches to 722 Wh kg − 1 . To fabricate a safe and flexible DMFC system, Zou et al [92] developed an agar gel/wood sponge composite material as methanol container, which is flexible and adaptable and shows high absorption rate and capacity of methanol (1.5% agar gel could reserve about 90% of methanol solution at 29.4 kPa). Due to no need for air pumps, self-breathing PEMFC shows the advantage in the flexible energy suppliers.…”

Stacked Microfluidic Paper Ethanol Fuel Cell with a Variety of Rapidly Prototyped Electrodes: Optimization and Performance Investigation

“…[14] In addition, these cells require relatively inexpensive and non-noble metal electrodes such as nickel, silver, etc. [17,18] These electrode materials are due to the faster redox reaction kinetics than others. Methanol, ethanol, ethylene glycol, and isopropanol are the alcohols utilized as a fuel in the alcohol fuel cells because of their high energy densities, compared to hydrocarbons and gasoline.…”