A flexible micro direct methanol fuel cells array based on FPCB

Abstract

In recent years, flexible electronic technology has developed rapidly, of which flexible energy devices hold an important seat that determines the system’s capacity. In this study, we demonstrate an integrated direct methanol fuel cells (µDMFCs) array in a flexible form factor. The device contains 12 individual cells that reside on a flexible printed circuit board to enable flexibility. Each cell was designed as an energy-supply electronic component. Buckle-type end plates were implemented to replace the traditional bolts-and-nuts end plates, reducing the dead weight and volume of the device while increasing its energy density. A Polydimethylsiloxane cover on the anode side was designed to encapsulate the µDMFCs array and act as a reservoir for the methanol solution. The open-circuit voltage of the µDMFCs array is configurable can reach up to 6 V with serial connections. In the configuration containing 2 groups of 6 cells in series, the device reached a maximum power density of 7.5 mW/cm2 in its original state and up to 10 mW/cm2 during bending. This novel and practical design of µDMFCs array can greatly promote the application of µDMFCs on flexible and wearable electronics.