SECONDARY BATTERY STATE DETECTION DEVICE AND SECONDARY BATTERY STATE DETECTION METHOD

• US 20140347059A1
• Filed: 08/01/2014
• Published: 11/27/2014
• Est. Priority Date: 03/03/2012
• Status: Active Grant

• Current Assignee: Furukawa Automotive Systems Incorporated (Furukawa Electric Company Limited), Furukawa Electric Company Limited
• Original Assignee: Furukawa Automotive Systems Incorporated (Furukawa Electric Company Limited), Furukawa Electric Company Limited
• Inventors: SATO, Etsuzo, SUGIMURA, Takezo, WATANABE, Yuichi
• Granted Patent: US 10,451,683 B2
• Time in Patent Office: Days
• US Class Current: 324/430
• CPC Class Codes: F02N 11/0862 characterised by the electrical power supply means, e.g. battery
• CPC Class Codes: G01R 31/3647 for determining the ability of a battery to perform a critical function, e.g. cranking
• CPC Class Codes: G01R 31/387 Determining ampere-hour charge capacity or SoC
• 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 10/48 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: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/005 Detection of state of health [SOH]
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

To accurately determine whether an engine can be started while accurately detecting a degree of deterioration of a secondary battery, in a secondary battery state detecting device detecting a state of a secondary battery mounted on a vehicle, a measurement unit measures a value of an internal resistance of the secondary battery at an engine stop time. An estimation unit estimates a value of a diffusion resistance resulting from diffusion of an ion generated at an electrolytic solution of the secondary battery by supplying electric power to a starter motor at a starting time of the engine. A calculation unit calculates a starting voltage being a voltage for the starting of the engine from a resistance value obtained by adding the value of the diffusion resistance estimated by the estimation unit to the value of the internal resistance measured by the measurement unit.

Claims

1. A secondary battery state detecting device detecting a state of a secondary battery mounted on a vehicle, comprising:

a measurement unit measuring a value of an internal resistance of the secondary battery at an engine stop time;

an estimation unit estimating a value of a diffusion resistance resulting from diffusion of an ion generated at an electrolytic solution of the secondary battery by supplying electric power to a starter motor at a starting time of the engine; and

a calculation unit calculating a starting voltage being a voltage required for the starting of the engine from a resistance value obtained by adding the value of the diffusion resistance estimated by the estimation unit to the value of the internal resistance measured by the measurement unit, a starting current flowing when the engine is started, and a voltage before starting of the secondary battery.

2. The secondary battery state detecting device according to claim 1,

wherein the estimation unit estimates the value of the diffusion resistance based on a discharge current, a discharge time at the starting time of the engine, and a temperature of the secondary battery.

3. The secondary battery state detecting device according to claim 2,

wherein the estimation unit estimates the value of the diffusion resistance by setting at least one of the discharge current, the discharge time, and the temperature of the secondary battery as a fixed value, and setting the others as variable values, and an obtained value of the diffusion resistance is corrected based on a parameter which is set as the fixed value.

4. The secondary battery state detecting device according to claim 3,

wherein the estimation unit sets the temperature as the fixed value, the discharge current and the discharge time as the variable values, estimates the value of the diffusion resistance based on the discharge current and the discharge time at a predetermined temperature, and corrects the value of the estimated diffusion resistance based on an actually measured temperature of the secondary battery.

5. A secondary battery state detecting method detecting a state of a secondary battery mounted on a vehicle, comprising:

a measurement step measuring a value of an internal resistance of the secondary battery at an engine stop time;

an estimation step estimating a value of a diffusion resistance resulting from diffusion of an ion generated at an electrolytic solution of the secondary battery by supplying electric power to a starter motor at a starting time of the engine; and

a calculation step calculating a starting voltage being a voltage required for the starting of the engine from a resistance value obtained by adding the value of the diffusion resistance estimated at the estimation step to the value of the internal resistance measured at the measurement step, a starting current flowing when the engine is started, and a voltage before starting of the secondary battery.