Battery status monitoring apparatus and method

• US 20060273763A1
• Filed: 03/23/2004
• Published: 12/07/2006
• Est. Priority Date: 03/31/2003
• Status: Abandoned Application

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: Arai, Youichi, Miyazaki, Yoshiya
• Application Number:
  US10/551,385
• Publication Number:
  US 20060273763A1
• Time in Patent Office: Days
• US Class Current: 320/133
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• 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

Abstract

A microcomputer 23 monitors the battery condition by detecting a first deterioration degree caused by increase of an internal resistance of a battery 13 and a second deterioration degree caused by inactivation of an activation material in the battery 13 based on outputs of a current sensor 15 and a voltage sensor 17.

Claims

1. A battery condition monitor for monitoring a condition of a battery, comprising:

a first deterioration detector for detecting a first deterioration degree cause by increase of an internal resistance of the battery; and

a second deterioration detector for detecting a second deterioration degree caused by decrease of active material of the battery to cause decrease of a charge capacity of the battery,

wherein the condition of the battery is monitored based on the first deterioration degree and the second deterioration degree.

2. The battery condition monitor according to claim 1, wherein the first deterioration detector obtains a direct-current resistance of the battery based on a discharge current and terminal voltage of the battery detected in a high-rate discharging, and obtains a saturated polarization, as a saturated value of a voltage drop by the internal resistance other than the direct-current resistance, based on the discharge current and the terminal voltage of the battery detected in discharging, and the direct-current resistance of the battery, and detects the first deterioration degree based on the direct-current resistance and the saturated polarization.

3. The battery condition monitor according to claim 1, wherein the second deterioration detector detects the second deterioration based on a decreasing value of the charge capacity at full-charge of the battery at any time corresponding to the charge capacity at full-charge of a new battery.

5. The battery condition monitor according to claim 2, wherein the second deterioration detector detects the second deterioration based on a decreasing value of the charge capacity at full-charge of the battery at any time corresponding to the charge capacity at full-charge of a new battery.

4. A method of monitoring a battery condition comprising a step of monitoring the battery condition based on a first deterioration degree caused by increase of an internal resistance of the battery and a second deterioration degree indicating a decreasing value of active material of the battery to cause decrease of a charge capacity of the battery.