Porous electrode primary battery having state of charge sensing electrode

• US 4,126,735 A
• Filed: 10/21/1977
• Issued: 11/21/1978
• Est. Priority Date: 10/21/1977
• Status: Expired due to Term

• Current Assignee: United States Of America As Represented By The Secretary Of The Air Force
• Original Assignee: United States Of America As Represented By The Secretary Of The Air Force
• Inventors: Fritts, David H.
• Primary Examiner(s): LeFevour, Charles F.
• Application Number:
  US05/844,162
• Time in Patent Office: 396 Days
• Field of Search: 429/91-93, 429/178, 429/233, 429/218
• US Class Current: 429/91
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 50/569 Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals battery terminal connectors with integrated measuring arrangements G01R31/364
• CPC Class Codes: H01M 6/14 Cells with non-aqueous electrolyte
• CPC Class Codes: H01M 6/50 Methods or arrangements for servicing or maintenance, e.g. for maintaining operating temperature constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 6/5005 Auxiliary electrodes
• CPC Class Codes: H01M 6/5044 Cells or batteries structurally combined with cell condition indicating means
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

In a porous electrode primary battery a sensing grid is positioned in a cell on or near the surface of the porous cathode facing the separator and anode. The voltage measured between this sensing grid and the conventional cathode current collector grid is a function of the current distribution within the electrode which is continuously changing as the battery discharges, thus the measured voltage is indicative of the state of charge of the particular cell having the sensing grid and for a battery containing cooperatively connected cells, the state of the battery in general.

Claims

1. The improvement in a porous electrode primary battery comprising a cell having a porous carbon cathode with a surface and an electrical connector, an anode with a surface, a separator separating the said cathode and anode positioned adjacent and between the said cathode surface and the said anode surface, the said improvement to provide, while underload, a means for determining the state of charge of the said battery, comprising:

a voltage sensing grid positioned in the said porous cathode near the said surface of the cathode adjacent the said separator and means for measuring the voltage between the said voltage sensing grid and the said cathode electrical connector.

2. The improvement in a porous electrode primary battery comprising a cell having a porous carbon cathode with an electrical connection and an adjoining anode, the said improvement for determining the state of charge of the said battery while connected to a load, comprising:

a voltage sensing grid, having a connection tab, positioned in the said porous cathode near the surface adjacent the said adjoining anode for sensing the voltage potential at the location of said sensing grid relative to the cathode connection potential, whereby the magnitude of said potential is proportional to the said state of charge.

3. The structure as claimed in claim 2 wherein the said cathode has a surface adjoining the said anode and the said voltage sensing grid is positioned just below the said surface of the cathode.