Stack-type enzyme biofuel cell using a cellulose nanofiber sheet to absorb lactic acid from human sweat as fuel

摘要

An enzymatic biofuel cell (BFC) that uses lactic acid in human sweat as fuel to generate electricity is an attractive power source for wearable devices. A BFC capable of generating electricity with human sweat has been developed. It comprised a flexible tattoo seal type battery with silver oxide vapor deposited on a flexible material and conductive carbon nanotubes printed on it. The anode and cathode in this battery were arranged in a plane (planar type). This work proposes a thin laminated enzymatic BFC by inserting a cellulose nanofiber (CNF) sheet between two electrodes to absorb human sweat (stack-type). Optimization of the anode and changing the arrangement of electrodes from planar to stack type improved the output and battery life. The stack type is 43.20 μW / cm~2 at 180 mV, which is 1.25 times the maximum power density of the planar type.