Scale-up and control the voltage of sediment microbial fuel cell for charging a cell phone.

In this research, a power management system (PMS) has been developed to charge a cell phone battery based on sediment microbial fuel cells (SMFCs). The single SMFC produces a voltage of 1.16 V, which is too low for practical application. The voltage is increased by connecting several SMFCs in series or parallel, but the voltage reversal occurs when it is directly connected to the load. To prevent the voltage reversal, the super capacitor is first charged by the five different stack SMFCs and the charged super capacitor is used to provide the input power to a PMS. This PMS increases and regulates the input voltage of stack SMFCs up to 5.02 V for charging a cell phone battery. The charging and discharging times of the super capacitors have been investigated with five different stack SMFCs. In all five stack SMFCs, only module-5 provides power to PMS for long periods (13 min). Further, the cell phone battery is continuously charged using the two parallel-connected stack SMFCs similar to the module-5. The battery has been fully charged in 26 h using 72 SMFCs. The charged battery is used to perform for three purposes; voice calling, music playing and LED strip lighting. This study is informative for the application of SMFC in an off-grid location.