Application of an electroosmotic (EO) pump in power electronics cooling and in the direct methanol fuel cell (DMFC) of a portable system

In this paper we present a study on the integration of the hydraulic circuit of the thermal cooling system of a portable power electronic device (like laptops) with the one which reforms a direct methanol fuel cell DMFC that is supplying power to this portable electronic system. This integration is done via a porous electroosmotic (EO) pump. The theory of the EO pumping, the analytical study and a modelling of this phenomenon in a porous medium are presented. A design of porous EO pump has been fabricated with a sintered pure silica disk. The pump has been tested with various liquids: deionised (DI) water, 10% methanol, 100% methanol and NaCl electrolyte for various conductivities. The pump generates until 30 ml/min and 0.3 Atm and it works under applied voltage between 25 V to 200 V. The power consumed by the pump is less than 1 W. The EO pump works without any noise and no bubbles were observed in the hydraulic circuit. The realized porous EO pump can be used to cool 100 W of power generated by the power electronic components with a forced convection without evaporation and 200 W with evaporation. It can be used to reform direct methanol fuel cell DMFC for various concentrations of methanol up to 100%.