Method and system to ensure full functionality of battery pack assembly using thermal imaging

• US 6,462,551 B1
• Filed: 01/18/2002
• Issued: 10/08/2002
• Est. Priority Date: 01/18/2002
• Status: Expired due to Fees

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Mellchar, Robert John, Coates, Calvin Edward
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/683,559
• Time in Patent Office: 263 Days
• Field of Search: 324/426, 324/431, 324/433, 324/437, 320/132, 320/150, 320/153
• US Class Current: 324/431
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: G01N 25/72 Investigating presence of flaws
• CPC Class Codes: G01R 31/3865 related to manufacture, e.g. testing after manufacture
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/4285 Testing apparatus
• 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 invention is a method and system to efficiently ensure functionality of a battery pack during assembly using thermal imaging. After individual battery modules are combined into sections, such as for a high voltage battery pack to power a traction motor for an electric vehicle, a power discharge test using thermal imaging is conducted on each section before combined to form the battery pack. This can determine whether any connections are loose or faulty based on the additional heat generated and detected at the site and allow them to be fixed during assembly. Further tests can include a comparison of voltage among the battery pack and each battery section and a means to adjust any battery pack that exceeds a predetermined voltage variation. The thermal image scan can obtain thermal radiation variation using infrared intensity data that can be digitized, processed, assigned color values, put on a visual display and recorded.

Claims

1. A system to ensure full functionality of a battery pack using thermal imaging, comprising:

at least two battery modules, the battery modules having electrode terminals;

a battery section comprising an electrical combination of the battery modules, the battery modules combined by a first set of connectors between an electrode terminal of one battery module to an electrode terminal of another battery module;

a system using a first thermal image scan of the battery section during a first power discharge test to determine whether the connections among the battery modules are within a first predetermined temperature tolerance;

a battery pack comprising an electrical combination of at least two battery sections, wherein a second set of connectors connect a terminal of one battery section to a terminal of another battery section;

a system using a second thermal image scan of the battery pack during a second power discharge test to determine whether the connections among the battery sections are within a second predetermined temperature tolerance; and

a means to fix any connections that exceed the first or second predetermined temperature threshold.

2. The system of claim 1 wherein the system further comprises a comparison of voltage among the battery pack and each battery section and a means to adjust any battery pack that exceeds a predetermined voltage variation.

3. The system of claim 1 wherein the battery module connections are combined in a series configuration.

4. The system of claim 1 wherein the battery module connections are combined in a parallel configuration.

5. The system of claim 1 wherein the thermal image scan comprises a means to obtain thermal radiation variation using infrared intensity data.

6. The system of claim 5 wherein infrared intensity data is digitized and processed so that infrared intensity values are assigned color values and put on a visual display.

7. A method of ensuring full functionality of a battery pack using thermal imaging during assembly, the steps comprising:

combining at least two battery modules to form a battery section by connecting the battery modules with a first set of connectors between an electrode terminal of one battery module to an electrode terminal of another battery module;

scanning a first thermal image of the battery section during a first power discharging test;

determining whether the connecting among all the battery modules within the battery section are within a first predetermined temperature tolerance;

fixing any connections not within the first predetermined temperature tolerance;

combining the battery sections to form a battery pack, by connecting the battery sections with a second set of connectors between an electrode terminal of one battery section to an electrode terminal of another battery section;

scanning a second thermal image of the battery pack during a second power discharging test;

determining whether the connecting among all the battery sections within the battery pack are within a second predetermined temperature tolerance; and

fixing any connections not within the second predetermined temperature tolerance.

8. The method of claim 7 wherein the system further comprises the step of comparing voltage output among the battery pack and each battery section and adjusting any battery pack that exceeds a predetermined voltage variation.

9. The method of claim 7 wherein the step of combining the battery modules occurs in a series configuration.

10. The method of claim 7 wherein the step of combining the battery modules occurs in a parallel configuration.

11. The method of claim 7 wherein scanning the first and second thermal image comprises the step of obtaining thermal radiation variation using infrared intensity data.

12. The method of claim 11 wherein the step of obtaining thermal radiation variation comprises the steps of digitizing and processing infrared intensity data, assigning color values to infrared intensity values, and displaying the colors visually.