Heating system for a battery module and method of heating the battery module

• US 8,974,928 B2
• Filed: 06/30/2011
• Issued: 03/10/2015
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Robertson, David C.
• Primary Examiner(s): D'Aniello, Nicholas P
• Application Number:
  US13/173,277
• Publication Number:
  US 20130004803A1
• Time in Patent Office: 1,349 Days
• Field of Search: 429/62, 429/50
• US Class Current: 429/50
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/615 Heating or keeping warm
• CPC Class Codes: H01M 10/633 characterised by algorithms, flow charts, software details or the like
• CPC Class Codes: H01M 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 10/6571 Resistive heaters arrangements for heating the battery by its resistance to the internal current H01M10/637
• 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 heating system and a method for heating a battery module are provided. The method includes generating a first signal indicative of a first voltage level being output by a first battery cell group, and generating a second signal indicative of a second voltage level being output by a second battery cell group. The method includes generating a temperature signal indicative of a temperature level of at least one of the first battery cell group and the second battery cell group. If the temperature level is less than a threshold temperature level, and the first battery cell group is not electrically balanced with the second battery cell group then the method includes selecting one of the first and second battery cell groups to be at least partially discharged through a resistor to generate heat energy in the resistor.

Claims

1. A heating system for a battery module, the battery module having first and second battery cell groups, comprising:

a first voltage sensor being coupled to first and second nodes of the first battery cell group, the first battery cell group having a first battery cell and a second battery cell, the first battery cell having a first positive terminal and a first negative terminal, the second battery cell having a second positive terminal and a second negative terminal, the first and second positive terminals being coupled to the first node, the first and second negative terminals being coupled to the second node, the first voltage sensor configured to generate a first signal indicative of a first voltage level being output by the first battery cell group between the first and second nodes;

a second voltage sensor being coupled to third and fourth nodes of the second battery cell group, the third node being coupled to the second node, the second battery cell group having a third battery cell and a fourth battery cell, the third battery cell having a third positive terminal and a third negative terminal, the fourth battery cell having a fourth positive terminal and a fourth negative terminal, the third and fourth positive terminals being coupled to the third node, the third and fourth negative terminals being coupled to the fourth node, the second voltage sensor configured to generate a second signal indicative of a second voltage level being output by the second battery cell group between the third and fourth nodes;

a series combination of a first switch and a first resistor being electrically coupled in series between the first node and the second node, the first resistor being electrically coupled in parallel to the first battery cell group when the first switch has a first operational position;

a series combination of a second switch and a second resistor being electrically coupled in series between the third node and the fourth node, the second resistor being electrically coupled in parallel to the second battery cell group when the second switch has a first operational position;

a temperature sensor configured to generate a temperature signal indicative of a temperature level of at least one of the first battery cell group and the second battery cell group;

a computer being operably coupled to the first voltage sensor, the second voltage sensor, and the temperature sensor such that the computer receives the first signal, the second signal, and the temperature signal, respectively;

the computer being further operably coupled to the first switch and the second switch;

the computer being programmed to determine if the first battery cell group is electrically balanced with the second battery cell group based on the first and second signals;

the computer being further programmed to select one of the first and second battery cell groups to be at least partially discharged, if the temperature level is less than a threshold temperature level, and the first battery cell group is not electrically balanced with the second battery cell group;

the computer being further programmed to generate a first control signal to induce the second switch to have the first operational position to at least partially discharge the second battery cell group through the second resistor to generate heat energy in the second resistor, if the second battery cell group is selected; and

the computer being further programmed to generate a second control signal to turn on a fan to distribute the heat energy in the battery module to increase the temperature level of the battery module.

2. The heating system of claim 1, wherein the computer being further programmed to select one of the first and second battery cell groups comprises the computer being programmed to select the second battery cell group if the first voltage level is less than the second voltage level based on the first and second signals.

3. The heating system of claim 1, wherein the computer being further programmed to select one of the first and second battery cell groups comprises the computer being programmed to select the second battery cell group if a first state-of-charge of the first battery cell group is less than a second state-of-charge of the second battery cell group.

4. The heating system of claim 1, wherein the computer being further programmed to select one of the first and second battery cell groups comprises the computer being programmed to select the first battery cell group if the first voltage level is greater than the second voltage level based on the first and second signals.

5. The heating system of claim 1, wherein the computer being further programmed to select one of the first and second battery cell groups comprises the computer being programmed to select the first battery cell group if a first state-of-charge of the first battery cell group is greater than a second state-of-charge of the second battery cell group.

6. The heating system of claim 1, wherein the computer being further programmed to determine if the temperature signal indicates that the temperature level is greater than or equal to the threshold temperature level,

the computer being further programmed to stop generating the first control signal to induce the second switch to have a second operational position to stop discharging the second battery cell group through the second resistor, if the temperature level is greater than or equal to the threshold temperature level;

and

the computer being further programmed to stop generating the second control signal to turn off the fan.

7. The heating system of claim 1, wherein the computer being further programmed to generate a third control signal to induce the first switch to have the first operational position to at least partially discharge the first battery cell group through the first resistor, if the temperature level is less than the threshold temperature level and the first battery cell group is selected.

8. The heating system of claim 1, wherein

the computer being programmed to generate a third control signal to induce the second switch to have the first operational position to at least partially discharge the second battery cell group through the second resistor to generate heat energy in the second resistor, if both the first battery cell group is electrically balanced with the second battery cell group, and the temperature level is less than the threshold temperature level;

the computer being further programmed to generate a fourth control signal to induce the first switch to have the first operational position to at least partially discharge the first battery cell group through the first resistor to generate heat energy in the first resistor, if both the first battery cell group is electrically balanced with the second battery cell group, and the temperature level is less than the threshold temperature level; and

the computer being further programmed to generate a fifth control signal to turn on the fan to distribute the heat energy from the first and second resistors in the battery module to increase the temperature level of the battery module.

9. The heating system of claim 1, further comprising:

a housing enclosing the first and second resistors, the temperature sensor, the first and second voltage sensors, and the first and second switches therein; and

the computer being disposed outside of the housing.

10. A heating system for a battery module, the battery module having first and second battery cell groups, comprising:

a first voltage sensor being coupled to first and second nodes of the first battery cell group, the first battery cell group having a first battery cell and a second battery cell, the first battery cell having a first positive terminal and a first negative terminal, the second battery cell having a second positive terminal and a second negative terminal, the first and second positive terminals being coupled to the first node, the first and second negative terminals being coupled to the second node, the first voltage sensor configured to generate a first signal indicative of a first voltage level being output by the first battery cell group between the first and second nodes;

a second voltage sensor being coupled to third and fourth nodes of the second battery cell group, the third node being coupled to the second node, the second battery cell group having a third battery cell and a fourth battery cell, the third battery cell having a third positive terminal and a third negative terminal, the fourth battery cell having a fourth positive terminal and a fourth negative terminal, the third and fourth positive terminals being coupled to the third node, the third and fourth negative terminals being coupled to the fourth node, the second voltage sensor configured to generate a second signal indicative of a second voltage level being output by the second battery cell group between the third and fourth nodes;

a series combination of a first switch and a first resistor being electrically coupled in series the first node and the second node, the first resistor being electrically coupled in parallel to the first battery cell group when the first switch has a first operational position;

a series combination of a second switch and a second resistor being electrically coupled in series between the third node and the fourth node, the second resistor being electrically coupled in parallel to the second battery cell group when the second switch has a first operational position;

a temperature sensor configured to generate a temperature signal indicative of a temperature level of at least one of the first battery cell group and the second battery cell group;

a computer being operably coupled to the first voltage sensor, the second voltage sensor, and the temperature sensor such that the computer receives the first signal, the second signal, and the temperature signal, respectively;

the computer being further operably coupled to the first switch and the second switch;

the computer being programmed to select the second battery cell group to be at least partially discharged, if both the second voltage level is greater than the first voltage level, and the temperature level is less than a threshold temperature level;

the computer being further programmed to generate a first control signal to induce the second switch to have the first operational position to at least partially discharge the second battery cell group through the second resistor to generate heat energy in the second resistor, if the second battery cell group is selected; and

the computer being further programmed to generate a second control signal to turn on a fan to distribute the heat energy in the battery module to increase the temperature level of the battery module.

11. The heating system of claim 10, wherein:

the computer being further programmed to select the first battery cell group to be at least partially discharged, if both the first voltage level is greater than the second voltage level, and the temperature level is less than the threshold temperature level; and

the computer being further programmed to generate a third control signal to induce the first switch to have the first operational position to at least partially discharge the first battery cell group through the first resistor to generate heat energy in the first resistor, if the first battery cell group is selected.

12. The heating system of claim 10, further comprising:

a housing enclosing the first and second resistors, the temperature sensor, the first and second voltage sensors, and the first and second switches therein; and

the computer being disposed outside of the housing.

13. A heating system for a battery module, the battery module having first and second battery cell groups, comprising:

a first voltage sensor being coupled to first and second nodes of the first battery cell group, the first battery cell group having a first battery cell and a second battery cell, the first battery cell having a first positive terminal and a first negative terminal, the second battery cell having a second positive terminal and a second negative terminal, the first and second positive terminals being coupled to the first node, the first and second negative terminals being coupled to the second node, the first voltage sensor configured to generate a first signal indicative of a first voltage level being output by the first battery cell group between the first and second nodes;

a second voltage sensor being coupled to third and fourth nodes of the second battery cell group, the third node being coupled to the second node, the second battery cell group having a third battery cell and a fourth battery cell, the third battery cell having a third positive terminal and a third negative terminal, the fourth battery cell having a fourth positive terminal and a fourth negative terminal, the third and fourth positive terminals being coupled to the third node, the third and fourth negative terminals being coupled to the fourth node, the second voltage sensor configured to generate a second signal indicative of a second voltage level being output by the second battery cell group between the third and fourth nodes;

a series combination of a first switch and a first resistor being electrically coupled in series between the first node and the second node, the first resistor being electrically coupled in parallel to the first battery cell group when the first switch has a first operational position;

a series combination of a second switch and a second resistor being electrically coupled in series between the third node and the fourth node, the second resistor being electrically coupled in parallel to the second battery cell group when the second switch has a first operational position;

a temperature sensor configured to generate a temperature signal indicative of a temperature level of at least one of the first battery cell group and the second battery cell group;

a computer being operably coupled to the first voltage sensor, the second voltage sensor, and the temperature sensor such that the computer receives the first signal, the second signal, and the temperature signal, respectively;

the computer being further operably coupled to the first switch and the second switch;

the computer being programmed to determine a first state-of-charge of first battery cell group based on the first voltage level, the second state-of-charge of the second battery cell group based on the second voltage level;

the computer being further programmed to select the second battery cell group to be at least partially discharged, if both the second state-of-charge is greater than the first state-of-charge, and the temperature level is less than a threshold temperature level;

the computer being further programmed to generate a first control signal to induce the second switch to have the first operational position to at least partially discharge the second battery cell group through the second resistor to generate heat energy in the second resistor, if the second battery cell group is selected; and

the computer being further programmed to generate a second control signal to turn on a fan to distribute the heat energy in the battery module to increase the temperature level of the battery module.

14. The heating system of claim 13, wherein:

the computer being further programmed to select the first battery cell group to be at least partially discharged, if both the first state-of-charge is greater than the second state-of-charge, and the temperature level is less than the threshold temperature level; and

the computer being further programmed to generate a third control signal to induce the first switch to have the first operational position to at least partially discharge the first battery cell group through the first resistor to generate heat energy in the first resistor, if the first battery cell group is selected.