Method and device for judging the condition of secondary batteries and method for regenerating secondary batteries

• US 20050214633A1
• Filed: 05/18/2005
• Published: 09/29/2005
• Est. Priority Date: 08/10/1998
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Ito, Takashi, Minohara, Taketoshi, Nakamura, Kenji
• Granted Patent: US 7,235,326 B2
• Time in Patent Office: Days
• US Class Current: 429/49
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: H01M 10/4242 Regeneration of electrolyte or reactants
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The internal resistance related value which is related to the internal resistance of a secondary battery is compared with a previously obtained relation between the internal resistance related value and battery condition to judge the battery condition of the secondary battery. Since the internal resistance related value is a value related to the internal resistance which closely depends on the battery condition, the battery condition can be judged in detail based on the above relation. And the internal resistance related value can be obtained more speedily with a predetermined method. On the other hand, when the level of the degradation of a negative electrode is low, an electrolyte is supplemented, and when the level of the degradation of the negative electrode is high, a reducing agent is added to the electrolyte to regenerate the secondary battery. With this regenerating method, the performance of the negative electrode can be recovered without degrading a positive electrode.

Claims

1. A method for regenerating a secondary battery, characterized in that an electrolyte is only supplemented without performing a reducing treatment when the level of the degradation of a negative electrode is low, and said negative electrode is taken from a battery container and is subjected to a reducing treatment when the level of the degradation of said negative electrode is high.

2. A method as claimed in claim 1, wherein a negative electrode active material is mechanically separated from said negative electrode in a nonoxidized liquid, and is subjected to a reducing treatment.