Method for checking a storage battery

• US 4,044,300 A
• Filed: 06/24/1976
• Issued: 08/23/1977
• Est. Priority Date: 06/24/1975
• Status: Expired due to Term

• Current Assignee: Compagnie Europeenne d'Accumulateurs, S.A.
• Original Assignee: Compagnie Europeenne d'Accumulateurs, S.A.
• Inventors: Lasserre, Pierre, Dupuis, Jean-Michel
• Primary Examiner(s): Rolinec, Rudolph V.
• Assistant Examiner(s): Tokar, Michael J.
• Application Number:
  US05/699,401
• Time in Patent Office: 425 Days
• Field of Search: 320/48, 320/15, 320/18, 320/31, 324/29.5, 324/30 R
• US Class Current: 324/434
• CPC Class Codes: G01R 31/379 for lead-acid batteries
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: G07C 3/14 Quality control systems
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 6/5011 for several cells simultaneously or successively
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• 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: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

A method of checking a storage battery with series-connected cells comprises the steps of:

Passing a charging current pulse through the battery,

Measuring an elementary transient voltage at the terminals of each storage cell; and

Comparing elementary transient voltages with the average transient voltage of the said storage cells (total transient voltage divided by the number of storage cells).

The battery is rejected if the absolute value of the difference between the said average transient voltage and one of the elementary transient voltages, when the difference maintains a constant sign, becomes higher than a predetermined threshold and, when the difference changes signs, if the sum of the maximum absolute values of the differences in constant sign becomes higher than a predetermined threshold. Application: checking lead-acid storage batteries when they come off the production line.

Claims

1. A method of checking a storage battery with series-connected cells comprising the following steps:

passing a charging current pulse through the battery;

measuring elementary transient voltages at the terminals of each storage cell; and

measuring a total transient voltage and dividing the total voltage by the number of storage cells to obtain an average transient voltage,

comparing the elementary transient voltages with the average transient voltage of said storage cells; and

providing a battery reject signal as a result of said comparing if the absolute value of the difference between said transient voltage and one of the elementary transient voltages, becomes higher than a predetermined threshold.

2. The method according to claim 1, wherein said elementary transient voltage measuring step comprises taking point measurements of the transient voltages at a first instant at the beginning of the charge current pulse, after approximately one second and at a second instant in substantially the middle part of said pulse.

3. The method according to claim 2, wherein the battery reject signal is provided if the difference resulting from the second embodiment is greater than a predetermined threshold when the differences resulting from the first and from the second measurement are positive.

4. The method according to claim 2, wherein the battery reject signal is provided if the absolute value of the difference resulting from the first measurement is greater than a predetermined threshold when the differences resulting from the first and from the second measurement are negative.

5. The method according to claim 2, wherein the battery reject signal is provided if the sum of the absolute values of said differences is greater than a predetermined threshold when the differences resulting from the first and from the second measurement have opposite signs.

6. The method according to claim 1, wherein the step of passing a charge current pulse comprises passing a charge current square wave pulse whose intensity is a few amperes and which last a few seconds.

7. The method according to claim 1, wherein the step of passing a charge current pulse comprises passing a current charge pulse which has an intensity which increases in proportion to time and is in the order of a few amperes.

8. A device for checking a storage battery with series connected cells, said device comprising:

means for passing a charging current pulse through the battery,

means for measuring elementary transient voltages at the terminals of each storage cell, and means for measuring a total transient voltage and dividing the total voltage by the number of storage cells to obtain an average transient voltage,

means for comparing the elementary transient voltages with the average transient voltage of the storage cells and for providing a battery reject signal as a result of said comparing if the absolute value of the difference between said average transient voltage and one of the elementary transient voltages, becomes higher than a predetermined threshold.