Onboard Battery Management Device

• US 20090051364A1
• Filed: 03/28/2006
• Published: 02/26/2009
• Est. Priority Date: 03/30/2005
• Status: Active Grant

• Current Assignee: PCN Corp. (CMIC Holdings Co., Ltd.)
• Original Assignee: PCN Corp. (CMIC Holdings Co., Ltd.)
• Inventors: Homma, Sumio, Ishida, Koroku, Homma, Shigeki, Homma, Toshiko, Kawakami, Takahiro, Kaneko, Futao
• Granted Patent: US 7,898,263 B2
• Time in Patent Office: Days
• US Class Current: 324/430
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• 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: 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 7/0048 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: H02J 7/14 for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery management device is provided for accurately measuring in a simple manner the internal resistance (reciprocal of conductance) of a battery that serves as the determination reference of the deterioration level of a battery without the application of an AC voltage to the battery while the battery remains onboard, and determining and displaying the deterioration level of the onboard battery. The onboard battery management device has sensors 2 and 3 for measuring terminal voltage and current of an onboard battery 1; a computation processor 6 for determining the deterioration level of a battery (as well as for calculating and determining the internal resistance on the basis of the measured value); and a display unit 7 of the battery state, wherein the internal resistance is determined based on an AC voltage component and an AC electric current component that are calculated by performing differential processing or subtractive processing on the voltage value and electric current value of the onboard battery during engine operation measured without the application of an AC signal from a sensor terminal; and the DC component, the low-frequency component, and the high-frequency component are removed using a filter circuit to determine the deterioration level.

Claims

1. An onboard battery management device for managing the deterioration level of an onboard battery during engine operation, the device comprising:

sensors for measuring terminal voltage and terminal current of an onboard battery;

a computation processor for calculating and determining internal resistance on the basis of said measured value and determining the deterioration level of a battery; and

a display unit of the battery state provided in a viewable location from the driver'"'"'s seat, wherein

the internal resistance is determined based on an AC voltage component and an AC electric current component that are calculated by performing differential processing and subtractive processing on the voltage value and electric current value of the onboard battery during engine operation measured by sampling several times per second to several thousand times per second without the application of an AC signal from a sensor terminal during engine operation; and

the internal resistance is converted to the internal resistance, i.e. static resistance value, prior to engine startup when the battery is not operating using a conversion formula established in advance based on data, is furthermore converted to cold cranking amperage that is based on said static resistance value, and the deterioration level of the battery is determined based on the cold cranking amperage.

3. The onboard battery management device according to claim 1, wherein differential processing or subtractive processing is performed while the voltage value and the electric current value of the onboard battery are measured during engine operation, a low frequency component at a prescribed level or lower is removed, and a high frequency component at a prescribed level or higher is removed by smoothing to determine the internal resistance based on a specified AC voltage component and an AC electric current component.

7. The onboard battery management device according to any of claims 1 through 5, comprising temperature sensors, wherein the charging state of the battery during engine operation is determined by the generated voltage of the temperature-corrected battery, and an onboard battery charging state display function for displaying the charging state is provided.

2. An onboard battery management device,

for managing the deterioration level of an onboard battery during engine operation, the device comprising:

sensors for measuring terminal voltage and terminal current of an onboard battery;

a computation processor for calculating and determining internal resistance on the basis of said measured value and determining the deterioration level of a battery; and

a display unit of the battery state provided in a viewable location from the driver'"'"'s seat, wherein

the internal resistance is determined based on an AC voltage component and an AC electric current component that are specified by passing a voltage value and electric current value of the onboard battery at the time of engine startup through a filter circuit to remove a low frequency component and a high frequency component without the application of an AC signal from a sensor terminal during engine operation; and

the internal resistance is converted to the internal resistance, i.e., static resistance, prior to engine startup when the battery is not operating using a conversion formula established in advance based on data, is furthermore converted to cold cranking amperage that is based on the static resistance value, and the deterioration level of the battery is determined based on the cold cranking amperage.

4. The onboard battery management device according to claim 2, wherein the voltage value and the electric current value of the onboard battery are measured during engine operation while being passed through a band pass filter circuit or a high-pass filter circuit, whereby a DC component and a low frequency component of several hertz or lower are removed, and a high frequency component at a prescribed level or higher is removed by a low-pass filter circuit to determine the internal resistance on the basis of a specified AC voltage component and AC electric current component.

5. An onboard battery management device, for managing the deterioration level of an onboard battery during engine operation, the device comprising:

sensors for measuring terminal voltage and terminal current of an onboard battery;

a computation processor for calculating internal resistance on the basis of said measured value, and determining the deterioration level of a battery; and

a display unit of the battery state provided in a viewable location from the driver'"'"'s seat, wherein

the internal resistance of the battery is calculated and determined based on voltage that has decreased due to drive current and starter drive current during vehicle startup, and the internal resistance is converted to the internal resistance, i.e., static resistance, prior to engine startup when the battery is not operating using a conversion formula established in advance based on data, is furthermore converted to cold cranking amperage that is based on the static resistance value, and the deterioration level of the battery is determined based on the cold cranking amperage.

6. (canceled)

8. (canceled)