Patent ID: 8348930

Claim:
A fluid delivery device, comprising: an electrochemical pump for transporting water, the electrochemical pump comprising an electrochemical pump product chamber configured to retain water transported by the electrochemical pump, an active electrode, an auxiliary electrode configured for ionic communication with the active electrode, an ion-exchange membrane positioned between the active electrode and the auxiliary electrode, wherein the ion-exchange membrane is configured to transport water by osmosis and electro-osmosis between the active electrode and the auxiliary electrode into the electrochemical pump product chamber, wherein one of the electrodes is located in the first chamber portion of the electrochemical pump product chamber, and the other electrode is located on an opposite side of the ion-exchange membrane; a reservoir configured to contain a fluid to be delivered; a displaceable member positioned between the electrochemical pump product chamber and the reservoir, wherein the displaceable member is responsive to the electrochemical pump transporting water into the electrochemical pump product chamber; and a diffuse membrane configured to generate increased pressure within the electrochemical pump product chamber, wherein the diffuse membrane is located within the electrochemical pump product chamber, wherein the diffuse membrane at least partially defines a first chamber portion and a second chamber portion within the electrochemical pump product chamber, and wherein the diffuse membrane comprises a substantially planar barrier with at least one hole therethrough having cross-sectional dimensions to prevent substantially all advection of water from the first chamber portion to the second chamber portion in the absence of electro-osmosis through the ion-exchange membrane.