LEAD-ACID BATTERY TEST METHOD

• US 3,857,087 A
• Filed: 04/12/1973
• Issued: 12/24/1974
• Est. Priority Date: 04/12/1973
• Status: Expired due to Term

• Current Assignee: David C. Jones
• Original Assignee: David C. Jones
• Inventors: Jones, David C.
• Primary Examiner(s): Smith, Alfred E.
• Assistant Examiner(s): Hille, Rolf
• Application Number:
  US05/350,434
• Time in Patent Office: 621 Days
• Field of Search: 324/29.5 320/48,14
• US Class Current: 320/130
• CPC Class Codes: G01R 31/379 for lead-acid batteries
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• 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 7/00711 with introduction of pulses during the charging process
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10S 320/13 Fault detection
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

A method is disclosed for testing a lead-acid battery using both transient discharging and transient charging separated by a period of time to allow the battery to recover from either ion depletion or ion adsorption. The transient charging is carried out to determine the current required to obtain a predetermined level of polarization of the battery electrodes and the transient discharging is carried out to obtain a detectable polarization (voltage change due to current flow). True measurement values for transient current and polarization are obtained and such values are compared against reference values to determine battery quality.

Claims

1. A method for testing a lead-acid battery, the steps comprising:

a. subjecting a battery to both transient discharging and transient charging separated by a period of time to allow the battery to recover from either ion depletion or ion adsorption, said transient charging being carried out to obtain a predetermined level of polarization of the battery electrodes and the transient discharging being carried out to obtain a voltage change due to current flow to determine the polarization resulting from discharging, b. at a predetermined time before the end of said transient charging, measure the transient current, c. at a predetermined time before the end of the discharging period, measure the transient voltage, and d. compare the difference between the starting voltage of the battery and the measured transient voltage, and compare the diffference between the transient current and a predetermined reference current, whereby if both the voltage difference is above a predetermined polarization reference value and the transient current is less than said predetermined reference current value, the battery can be deemed defective.

2. A method for testing a multiple cell lead electrode and acid electrolyte battery having a known starting voltage, the steps comprising:

a. discharge the battery for a time period sufficient to obtain a voltage change due to a discharging current flow through the lead-acid interface, b. determine a first transient voltage of the battery immediately before the end of the discharge period and subtract this first transient voltage from said starting voltage to determine if polarization of the battery electrodes resulting from said discharge is above a predetermined reference value, c. allow the battery electrodes to rest a period of time to recover ions depleted by said discharge, d. terminate said rest period by forcing a charging current into said battery for a period of time to obtain a predetermined voltage change due to a current flow across the lead-acid interface and substantially devoid of electrochemical side reactions, and e. immediately before the end of said charging period, measure the charging transient current required to obtain said predetermined voltage change, and f. compare the difference between the charging transient current and a reference current, whereby if the charging transient current is less than a reference current value, the battery is deemed defective.

3. The method as in claim 2, in which the battery comprises six cells and the starting voltage is at least greater than 10 volts.

4. The method as in claim 3, in which the discharging period is restricted to about 5 seconds.

5. The method as in claim 3, in which the rest period is restricted to about 30 seconds.

6. The method as in claim 3, in which said charging period is restricted to about 55 milli-seconds and the predetermined voltage change from said charging results in a polarization level of about 15 volts.

7. The method of claim 4, in which discharging of said battery is carried out through a resistance of about 0.03 ohms.