BATTERY PACK, ENERGY STORAGE SYSTEM INCLUDING BATTERY PACK, AND METHOD OF CHARGING BATTERY PACK

• US 20150108950A1
• Filed: 02/24/2014
• Published: 04/23/2015
• Est. Priority Date: 10/22/2013
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Yun, Han-Seok
• Granted Patent: US 9,401,616 B2
• Time in Patent Office: Days
• US Class Current: 320/134
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• 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 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H01M 50/202 Casings or frames around the primary casing of a single cell or a single battery
• CPC Class Codes: H01M 50/204 Racks, modules or packs for multiple batteries or multiple cells
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery pack including: a battery including a battery cell; a temperature sensor for detecting a temperature of the battery; a cell voltage measuring unit for measuring a cell voltage of the battery cell and generating cell voltage data including a cell voltage value; a temperature measuring unit coupled to the temperature sensor, the temperature measuring unit being for generating temperature data including a temperature value corresponding to the temperature of the battery detected by the temperature sensor; and a control unit for determining a maximum charging current value (MCCV) of a charging current for charging the battery based on the cell voltage data and the temperature data. The control unit is for transmitting the MCCV to a charging apparatus for supplying the charging current to the battery pack. The charging apparatus is for controlling the charging current supplied to the battery pack to have a value below the MCCV.

Claims

1. A battery pack comprising:

a battery comprising at least one battery cell;

at least one temperature sensor configured to detect a temperature of the battery;

a cell voltage measuring unit configured to measure a cell voltage of the at least one battery cell and to generate cell voltage data comprising at least one cell voltage value;

a temperature measuring unit coupled to the at least one temperature sensor, the temperature measuring unit being configured to generate temperature data comprising at least one temperature value corresponding to the temperature of the battery detected by the at least one temperature sensor; and

a control unit configured to determine a maximum charging current value (MCCV) of a charging current for charging the battery based on the cell voltage data and the temperature data wherein the control unit is configured to transmit the MCCV to a charging apparatus configured to supply the charging current to the battery pack, and

wherein the charging apparatus is configured to control the charging current supplied to the battery pack to have a value below the MCCV.

2. The battery pack of claim 1, wherein the control unit is configured to determine a first MCCV based on the at least one cell voltage value, and to determine the MCCV based on the first MCCV.

3. The battery pack of claim 2, wherein the control unit is configured to:

determine a minimum cell voltage value among the at least one cell voltage value; and

determine the first MCCV based on the minimum cell voltage value according to first relationship data defining a correlation between the first MCCV and the minimum cell voltage value.

4. The battery pack of claim 3, wherein the control unit is configured to:

determine a first value as the first MCCV when the minimum cell voltage value is smaller than a first cell voltage threshold value;

determine a second value greater than the first value as the first MCCV when the minimum cell voltage value is greater than a second cell voltage threshold value, which is greater than the first cell voltage threshold value by a hysteresis margin; and

determine one of the first value or the second value as the first MCCV according to whether the minimum cell voltage value is increasing or decreasing when the minimum cell voltage value is greater than the first cell voltage threshold value and smaller than the second cell voltage threshold value.

5. The battery pack of claim 3, wherein the control unit is configured to:

determine a first value as the first MCCV when the minimum cell voltage value is smaller than a first cell voltage threshold value for a preset time period;

determine a second value greater than the first value as the first MCCV when the minimum cell voltage value is greater than a second cell voltage threshold value, which is greater than the first cell voltage threshold value by a hysteresis margin, for the preset time period; and

determine one of the first value or the second value as the first MCCV according to whether the minimum cell voltage value is increasing or decreasing when the minimum cell voltage value is greater than the first cell voltage threshold value and smaller than the second cell voltage threshold value for the preset time period.

6. The battery pack of claim 1, wherein the control unit is configured to:

determine a second MCCV based on the at least one temperature value; and

determine the MCCV based on the second MCCV.

7. The battery pack of claim 6, wherein the control unit is configured to:

determine a minimum temperature value among the at least one temperature value; and

determine the second MCCV based on the minimum temperature value according to second relationship data defining a correlation between the second MCCV and the minimum temperature value.

8. The battery pack of claim 7, wherein the control unit is configured to:

determine a first value as the second MCCV when the minimum temperature value is smaller than a first temperature threshold value;

determine a second value greater than the first value as the second MCCV when the minimum temperature value is greater than a second temperature threshold value, which is greater than the first temperature threshold value by a hysteresis margin; and

determine one of the first value or the second value as the second MCCV according to whether the minimum temperature value is increasing or decreasing when the minimum temperature value is greater than the first temperature threshold value and smaller than the second temperature threshold value.

9. The battery pack of claim 7, wherein the control unit is configured to:

determine a first value as the second MCCV when the minimum temperature value is smaller than a first temperature threshold value for a preset time period;

determine a second value greater than the first value as the second MCCV when the minimum temperature value is greater than a second temperature threshold value, which is greater than the first temperature threshold value by a hysteresis margin, for the preset time period; and

determine one of the first value or the second value as the second MCCV according to whether the minimum temperature value is increasing or decreasing when the minimum temperature value is greater than the first temperature threshold value and smaller than the second temperature threshold value for the preset time period.

10. The battery pack of claim 1, wherein the control unit is configured to determine a first MCCV based on the at least one cell voltage value, to determine a second MCCV based on the at least one temperature value, and to determine a smaller one between the first MCCV and the second MCCV as the MCCV.

11. An energy storage system comprising:

a battery system comprising a battery comprising at least one battery cell and a battery management unit configured to control charging and discharging of the battery; and

a power conversion system (PCS) comprising a power converting apparatus configured to convert power between a power generation system, a grid, and the battery system and an integrated controller configured to control the power converting apparatus,

wherein the battery management unit comprises;

a cell voltage measuring unit configured to measure a cell voltage of the at least one battery cell and to generate cell voltage data comprising at least one cell voltage value;

a temperature measuring unit configured to generate temperature data comprising at least one temperature value corresponding to a temperature of the battery detected by at least one temperature sensor in the battery; and

a control unit configured to determine a maximum charging current value (MCCV) of a charging current for charging the battery based on the cell voltage data and the temperature data and to transmit the MCCV to the integrated controller,

wherein the integrated controller is configured to receive the MCCV from the battery management unit and control the power converting apparatus to supply the charging current having a value below the MCCV to the battery system.

12. The energy storage system of claim 11, wherein the control unit is configured to determine a first MCCV based on the at least one cell voltage value, to determine a second MCCV based on the at least one temperature value, and to determine a smaller one between the first MCCV and the second MCCV as the MCCV.

13. The energy storage system of claim 12, wherein the control unit is configured to:

determine a minimum cell voltage value among the at least one cell voltage value; and

determine the first MCCV based on the minimum cell voltage value according to first relationship data defining a correlation between the first MCCV and the minimum cell voltage value.

14. The energy storage system of claim 12, wherein the control unit is configured to:

determine a minimum temperature value among the at least one temperature value; and

determine the second MCCV based on the minimum temperature value according to second relationship data defining a correlation between the second MCCV and the minimum temperature value.

15. A method of charging a battery pack comprising a battery comprising at least one battery cell, the method comprising:

measuring a cell voltage of the at least one battery cell;

generating cell voltage data comprising at least one cell voltage value corresponding to the cell voltage;

generating temperature data comprising at least one temperature value corresponding to a temperature of the battery measured by at least one temperature sensor;

determining a maximum charging current value (MCCV) of a charging current for charging the battery based on the cell voltage data and the temperature data

transmitting the MCCV to a charging apparatus coupled to the battery pack; and

supplying the charging current having a value below the MCCV from the charging apparatus.

16. The method of claim 15, wherein the determining of the MCCV comprises:

determining a first MCCV based on the at least one cell voltage value;

determining a second MCCV based on the at least one temperature value; and

determining a smaller one between the first MCCV and the second MCCV as the MCCV.