Method and system for monitoring the status of battery cells

• US 10,151,801 B2
• Filed: 06/02/2014
• Issued: 12/11/2018
• Est. Priority Date: 06/02/2014
• Status: Active Grant

• Current Assignee: Volvo Truck Corporation (AB Volvo)
• Original Assignee: Volvo Truck Corporation (AB Volvo)
• Inventors: Gelso, Esteban, Hellgren, Jonas
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): Curtis, Sean
• Application Number:
  US15/307,726
• Publication Number:
  US 20170074945A1
• Time in Patent Office: 1,653 Days
• Field of Search: 324426
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• 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: G01R 31/3646 for indicating electrical conditions or variables, e.g. visual or audible indicators
• 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: 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: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 50/569 Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals battery terminal connectors with integrated measuring arrangements G01R31/364
• 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

A method for monitoring the status of a plurality of connected battery cells in a battery pack includes: arranging the battery cells in at least two groups of cells; connecting the groups of cells to a sensor unit; and providing a measurement of at least one parameter indicative of the state of operation of the battery pack by the sensor unit. The method further includes arranging the groups of cells in a manner so that at least two of the groups include two or more cells and at least two of the groups overlap so that a cell forms part of the overlapping groups; and connecting the sensor unit to the groups; and wherein the number of groups is less than the number of cells.

Claims

1. A method for monitoring the status of a plurality of connected battery cells in a battery pack, the method comprising:

—

arranging the battery cells in at least two groups of cells;

—

connecting each one of the groups of cells to a corresponding sensor forming part of a sensor unit; and

—

providing a measurement of at least one parameter indicative of the state of operation of the battery pack by means of the sensor unit;

—

arranging the groups of cells in a manner so that;

—

at least two of the groups comprise two or more cells, and—

at least two of the groups overlap so that a cell forms part of the overlapping groups; and

—

connecting each sensor of the sensor unit to each one of the corresponding groups for estimating a measurement of the parameter for each one of the groups; and

wherein—

the number of groups is less than the number of cells.

2. A method according to claim 1, comprising:

—

arranging the groups of cells in a manner so that it fulfills the relationship;

number of groups−

number of cells/2≥

1.

3. A method according to claim 1 comprising:

—

using the sensors for measuring at least one parameter related to the state of operation of the battery cells, the parameter being at least one of the following;

the battery current (I);

the terminal voltage (V) of at least one cell; and

the temperature (T) of at least one cell.

4. A method according to claim 3, comprising:

—

estimating, based on the measured parameter, at least one of the following properties of each battery cell or groups of cells;

—

the state of charge;

—

the cell capacity; and

—

the resistance.

5. A method according to claim 1, comprising:

—

generating an indication of a fault in the event that the result of the measurement deviates from an expected value.

10. A computer comprising a program for performing the method steps of claim 1 when the program is run on the computer.

11. A non-transitory computer readable medium carrying a computer program for performing the steps of claim 1 when the program product is run on a computer.

12. A control unit for monitoring the status of a plurality of connected battery cells in a battery pack, the control unit being configured to perform the steps of the method according to claim 1.

6. A battery management system for monitoring the status of a plurality of connected battery cells in a battery pack, comprising:

—

a plurality of battery cells which are arranged in at least two groups of cells;

—

a sensor unit connected to the groups so that each one of the groups is connected to a corresponding sensor forming part of the sensor unit;

the sensor unit being configured for providing a measurement of at least one, parameter indicative of the state of operation of the battery pack; and

—

a control unit connected to the sensor unit;

—

an arrangement of the groups of cells wherein;

—

at least two of the groups comprise two or more cells, and—

at least two of the groups overlap so that a cell forms part of the overlapping groups; and

—

a connection between the each sensor of the sensor unit and each one of the corresponding groups for estimating a measurement of the parameter for each one of the groups;

wherein—

the number of groups is less than the number of cells.

7. A system according to claim 6, the sensors are configured for measuring at least one parameter related to the state of operation of the battery cells, the parameter being at least one of the following:

the battery current (I);

the terminal voltage (V) of at least one cell; and

the temperature (T) of at least one cell.

8. A system according to claim 6, the control unit is configured for generating an indication of a fault in the event that the result of the measurement deviates from an expected value.

9. A vehicle comprising a battery management system according to claim 6.