Battery management system

• US 20070090802A1
• Filed: 10/19/2006
• Published: 04/26/2007
• Est. Priority Date: 10/20/2005
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Seo, Se-Wook
• Granted Patent: US 7,602,144 B2
• Time in Patent Office: Days
• US Class Current: 320/128
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 58/14 Preventing excessive discharging
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/3828 using current integration
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• 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
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

The present invention relates to a battery management system for securely maintaining battery charging capacity and precisely measuring a battery pack voltage. The battery management system, which is coupled to a battery including a plurality of battery cells as one battery pack, includes a sensing stabilization unit, a relay, a battery pack voltage measurement signal generating unit, and an analog/digital (A/D) converter. The sensing stabilization unit includes a first and a second signal lines electrically coupled to a first and a second terminals of the battery, respectively, and maintains a stable potential difference between the first and second signal lines. The relay is turned on in response to a control signal, and transmits the potential difference between the first and second signal lines. The battery pack voltage measurement signal generating unit outputs a predetermined level of battery pack voltage measurement signal that is produced based on the potential difference between the first and second signal lines. The AID converter receives the battery pack voltage measurement signal and converts it into a digital signal.

Claims

1. A battery management system coupled to a battery, comprising:

a sensing stabilization unit including a first signal line and a second signal line coupled to a first terminal and a second terminal of the battery, respectively, the sensing stabilization unit maintaining a stable potential difference between the first signal line and the second signal line;

a battery pack voltage measurement signal generating unit coupled to the sensing stabilization unit, and outputting a battery pack voltage measurement signal that is produced based on the potential difference between the first signal line and the second signal line; and

an analog/digital (A/D) converter coupled to the battery pack voltage measurement signal generating unit, and receiving the battery pack voltage measurement signal and converting the battery pack voltage measurement signal into a digital signal.

2. The battery management system of claim 1, further comprising a current controlling unit coupled to the first signal line and the second signal line of the sensing stabilization unit, and coupled to the battery pack voltage measurement signal generating unit, the current controlling unit controlling amounts of currents flowing to the battery pack voltage measurement signal generating unit.

3. The battery management system of claim 2, comprised of the current controlling unit including:

a first resistor coupled to the first signal line; and

a second resistor coupled to the second signal line.

4. The battery management system of claim 1, further comprising a noise eliminating unit coupled to the battery pack voltage measurement signal generating unit, and eliminating a noise in the battery pack voltage measurement signal of the battery pack voltage measurement signal generating unit.

5. The battery management system of claim 1, comprised of the battery including a plurality of battery cells.

6. A battery management system coupled to a battery including a plurality of battery cells in a battery pack, comprising:

a control signal generator for generating a control signal, the control signal generator generating an on-level control signal when the battery management system is turned on;

a cell voltage measuring unit coupled to the battery, and measuring voltages of the plurality of the battery cells and outputting a plurality of cell voltage measurement signals;

a battery pack voltage measuring unit coupled to the battery and coupled to the control signal generator, the battery pack voltage measuring unit receiving the control signal from the control signal generator and measuring a battery pack voltage of the battery, the battery pack voltage measuring unit outputting a battery pack voltage measurement signal;

a battery pack current measuring unit coupled to the battery, and measuring a battery pack current of the battery and outputting a battery pack current measurement signal; and

an analog/digital converter receiving the cell voltage measurement signals, the battery pack voltage measurement signal, and the battery pack current measurement signal, the analog/digital converter converting the cell voltage measurement signals, the battery pack voltage measurement signal, and the battery pack current measurement signal to digital signals, respectively.

7. The battery management system of claim 6, comprised of the battery pack voltage measuring unit including:

a relay being turned on when the relay receives an on-level control signal from the control signal generator, the relay transmitting a potential difference between a first output terminal and a second output terminal of the battery; and

a battery pack voltage measurement signal generating unit coupled to the relay, and generating a battery pack voltage measurement signal produced based on the potential difference transmitted by the relay.

8. The battery management system of claim 7, comprised of the battery pack voltage measuring unit including:

a first resistor coupled to the first output terminal of the battery and coupled to a first input terminal of the relay; and

a second resistor coupled to the second output terminal of the battery and coupled to a second input terminal of the relay.

9. The battery management system of claim 7, comprised of the battery pack voltage measurement signal generating unit including an inverting differential amplifier for generating the battery pack voltage measurement signal.

10. The battery management system of claim 7, comprised of the relay not transmitting the potential difference between a first output terminal and a second output terminal of the battery when the battery management system is turned off.