# US 10,869,785 B2 · Liquid sensor for a diaper and method of manufacturing the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,869,785 B2 - Document ID: US10869785B2 - Status: Granted - Kind: B2 - Application number: 16/484,888 - Filed: 2018-02-08 - Published: 2019-12-12 - Granted: 2020-12-22 - Earliest claimed: 2017-02-09 - Assignees: Agency for Science, Technology and Research - Applicants: Agency for Science, Technology and Research - Inventors: Jackie Y. Ying; Guolin Xu; Rensheng Deng; Min Hu - Web page: https://patentgrep.com/patent/US10869785B2 ## CPC - A61F 13/42: with wetness indicator or alarm - G01N 27/27: Association of two or more measuring systems or cells, each measuring a different parameter, where the measurement results may be either used independently, the systems or cells being physically associated, or combined to produce a value for a further parameter - G01N 27/30: Electrodes, e.g. test electrodes; Half-cells (G01N27/414 takes precedence) - A61F 2013/424: {having an electronic device} - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract A liquid sensor for a diaper, and method of manufacturing the same are provided. The liquid sensor includes a plurality of electrochemical cells in series connection. Each of the plurality of electrochemical cells includes an anode, a cathode and a liquid-porous layer including an electrolyte solution. The liquid-porous layer electrically connects the anode to the cathode such that each cell has a respective predetermined potential difference across the cell. Two or more of the plurality of electrochemical cells are operable to be electrically connected by a liquid to form a single electrochemical cell having a potential difference lower than the sum of the predetermined potential differences of the two or more electrochemical cells. ## Claims ### Claim 1 A liquid sensor for a diaper, the liquid sensor comprising: a plurality of electrochemical cells in series connection, each of the plurality of electrochemical cells comprising: an anode; a cathode; and a liquid-porous layer comprising an electrolyte solution, the liquid-porous layer electrically connecting the anode to the cathode such that each cell has a respective predetermined potential difference across the cell; wherein: two or more of the plurality of electrochemical cells are operable to be electrically connected by a liquid to form a single electrochemical cell having a potential difference lower than the sum of the predetermined potential differences of the two or more electrochemical cells, the anode of each cell comprises a first end and a second end opposite the first end, wherein the liquid-porous layer of said cell is configured to enclose the first end, and the cathode of said cell comprises a hollow cylinder configured to at least partially surround the liquid-porous layer. ### Claim 2 (depends on 1) The liquid sensor of claim 1, further comprising a removable seal encapsulating each of the plurality of electrochemical cells, wherein the seal is gas impermeable. ### Claim 3 (depends on 1) The liquid sensor of claim 1, wherein the hollow cylinder comprises a plurality of holes formed thereon. ### Claim 4 (depends on 1) The liquid sensor of claim 1, wherein the second end of the anode of said cell is configured to be enclosed by a cathode of an adjacent electrochemical cell. ### Claim 5 (depends on 1) The liquid sensor of claim 1, further comprising a first conductor electrically connected to one end of the plurality of electrochemical cells and a second conductor electrically connected to another end of the plurality of electrochemical cells. ### Claim 6 (depends on 5) The liquid sensor of claim 5, further comprising a voltage sensor connected to the first and second conductors, the voltage sensor configured to measure a potential difference of the plurality of electrochemical cells. ### Claim 7 (depends on 1) The liquid sensor of claim 1, wherein the anode comprises aluminum or zinc, and wherein the cathode comprises copper or graphite. ### Claim 8 (depends on 1) The liquid sensor of claim 1, wherein the liquid porous material comprises one or more of a group consisting of: paper, cloth, polymeric absorbent and silica gel. ### Claim 9 (depends on 1) The liquid sensor of claim 1, wherein the plurality of electrochemical cells are spatially distributed over a urine collection area of the diaper. ### Claim 10 A method of manufacturing a liquid sensor, the method comprising: providing a plurality of electrochemical cells, each of the plurality of electrochemical cells comprising: an anode; a cathode; and a liquid-porous layer comprising an electrolyte solution, the liquid-porous layer electrically connecting the anode and the cathode such that each cell has a respective predetermined potential difference across the cell; and connecting the plurality of electrochemical cells in series connection; wherein: two or more of the plurality of electrochemical cells are electrically connectable by a liquid to form a single electrochemical cell having a potential difference lower than the sum of the predetermined potential differences of the two or more electrochemical cells; and, providing the plurality of electrochemical cells comprises: providing the anode of each cell, the anode having a first end and a second end opposite the first end; enclosing the first end of said cell with the liquid-porous layer; and at least partially surrounding the liquid-porous layer with the cathode of said cell, the cathode comprising a hollow cylinder having a plurality of holes formed thereon. ### Claim 11 (depends on 10) The method as claimed in claim 10, further comprising encapsulating each of the plurality of electrochemical cells with a removable seal, wherein the seal is gas impermeable. ### Claim 12 (depends on 10) The method as claimed in claim 10, wherein connecting the plurality of electrochemical cells comprises enclosing the second end of the anode of said cell with a cathode of an adjacent electrochemical cell. ### Claim 13 (depends on 10) The method as claimed in claim 10, further comprising electrically connecting a first conductor to one end of the plurality of electrochemical cells and a second conductor to another end of the plurality of electrochemical cells. ### Claim 14 (depends on 10) The method as claimed in claim 10, wherein the anode comprises aluminum or zinc, and wherein the cathode comprises copper or graphite. ### Claim 15 (depends on 10) The method as claimed in claim 10, wherein the liquid porous material comprises one or more of a group consisting of: paper, cloth, polymeric absorbent and silica gel. ### Claim 16 (depends on 1) A method of detecting wetness of a diaper, the method comprising: disposing the liquid sensor as claimed in claim 1 such that the plurality of electrochemical cells are spatially distributed over a urine collection area of the diaper; and detecting a reduction in an output voltage of the electrochemical cells. ### Claim 17 A liquid sensor for a diaper, the liquid sensor comprising: a plurality of electrochemical cells in series connection, each of the plurality of electrochemical cells comprising: an anode; a cathode; and a liquid-porous layer comprising an electrolyte solution, the liquid-porous layer electrically connecting the anode to the cathode such that each cell has a respective predetermined potential difference across the cell; wherein two or more of the plurality of electrochemical cells are operable to be electrically connected by a liquid to form a single electrochemical cell having a potential difference lower than the sum of the predetermined potential differences of the two or more electrochemical cells; and wherein the plurality of electrochemical cells are arranged laterally adjacent to each other to form a film, and wherein the film is disposed on an insulated substrate. ### Claim 18 A method of manufacturing a liquid sensor, the method comprising: providing a plurality of electrochemical cells, each of the plurality of electrochemical cells comprising: an anode; a cathode; and a liquid-porous layer comprising an electrolyte solution, the liquid-porous layer electrically connecting the anode and the cathode such that each cell has a respective predetermined potential difference across the cell; and connecting the plurality of electrochemical cells in series connection; wherein two or more of the plurality of electrochemical cells are electrically connectable by a liquid to form a single electrochemical cell having a potential difference lower than the sum of the predetermined potential differences of the two or more electrochemical cells; and wherein providing the plurality of electrochemical cells comprises: providing an insulated substrate; and disposing the plurality of electrochemical cells on the insulated substrate such that the plurality of electrochemical cells are arranged laterally adjacent to each other to form a film.