Method and a device for determining gas generation with electrodes in contact with electrolytes

• US 4,034,279 A
• Filed: 12/22/1975
• Issued: 07/05/1977
• Est. Priority Date: 07/13/1973
• Status: Expired due to Term

• Current Assignee: Boliden AB
• Original Assignee: Boliden AB
• Inventors: Nilsson, Bruno Yngve
• Primary Examiner(s): Hickey, Robert J.
• Application Number:
  US05/643,162
• Time in Patent Office: 561 Days
• Field of Search: 320/20, 320/21, 320/35, 320/36, 320/39, 320/40, 320/46
• US Class Current: 320/161
• CPC Class Codes: G01R 31/378 specially adapted for the type of battery or accumulator
• 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: H02J 7/00718 in response to charge current gradient
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

A method and a device for determining the charging condition of electric accumulators, wherein the potential variations at the electrolyte-electrode interface are time differentiated in order to determine the degree of gas development in said accumulators.

Claims

1. A method for controlling the charging condition of an electric accumulator, characterized by the steps of determining the resistance fluctuations at an electrolyte-electrode interface due to the gas generation by time differentiating the terminal voltage, rectifying and filtering the differentiated voltage to obtain a D.C. voltage, the level of which being a measure of the intensity of the gas generation process, sensing said level and governing the value of the charging current in response to the sensed level.

2. A device for controlling the charging condition of an electric accumulator, comprising a first and a second differentiator arranged to double differentiate the terminal voltage of the accumulator, a rectifier and a filter coupled in series and supplied by said second differentiator and adapted to deliver a D.C. voltage which is a measure of the intensity of the gas generation process in the accumulator, a comparator supplied by said D.C. voltage and being arranged to sense the level of said D.C. voltage, and means to govern the charging apparatus in response to the sensed level to reduce the charging current in order to maintain a low constant gas generation level in the accumulator during continued charging.