Battery Thermal Management System

• US 20190312323A1
• Filed: 06/21/2019
• Published: 10/10/2019
• Est. Priority Date: 11/04/2015
• Status: Active Grant

• Current Assignee: Boston Dynamics, Inc. (SoftBank Group Corp.)
• Original Assignee: Boston Dynamics, Inc. (SoftBank Group Corp.)
• Inventors: Dellon, Brian Todd, Saunders, John Aaron
• Granted Patent: US 11,121,421 B2
• Time in Patent Office: Days
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• CPC Class Codes: H01M 10/6552 Closed pipes transferring heat by thermal conductivity or phase transition, e.g. heat pipes
• CPC Class Codes: H01M 10/6569 Fluids undergoing a liquid-gas phase change or transition, e.g. evaporation or condensation heat pipes H01M10/6552
• CPC Class Codes: H01M 50/213 adapted for cells having curved cross-section, e.g. round or elliptic H01M50/209, H01M50/216 take precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

An example system is disclosed for thermal management of batteries. The system may include a cell bank that includes first and second cell frame sections, a heat bus, and thermal interface material. The first and second cell frame sections may define opposite surfaces of the cell bank. Each cell frame section may include recesses to align battery cells for welding and provided conductive connections between the cells to create a string of cells with a combined power output. Each recess may include a divider between the battery cells to preload the cells against a thermal junction during assembly. The heat bus may be provided between the cell frame sections. The heat bus may include heat pipes that extend between the battery cells and across the cell frame sections. The thermal interface material may be positioned to transfer heat from the cells to the heat pipes at their thermal junction.

Claims

1. A power supply device comprising:

an enclosure; and

one or more cell banks housed within the enclosure, each cell bank comprising;

a first cell frame section defining a first surface of the cell bank and including a plurality of recesses to align battery cells;

a second cell frame section defining a second surface of the cell bank opposite to the first surface of the cell bank and aligning the battery cells in conjunction with the first cell frame section, at least one of the first cell frame section or the second cell frame section comprising conductive connectors for the battery cells, the conductive connectors configured to generate a combined power output for the battery cells;

one or more portions of thermal interface material contacting the battery cells to transfer heat from the battery cells;

a vapor chamber located between and spaced apart from the first cell frame section and the second cell frame section, the vapor chamber forming a serpentine path extending between the battery cells, and, along the serpentine path, the vapor chamber contacts the one or more portions of thermal interface material promoting heat transfer from the battery cells to the vapor chamber; and

a spring configured to generate a spring force against at least one of the battery cells along the serpentine path of the vapor chamber, the spring force causing the vapor chamber to increase contact with the one or more portions of the thermal interface material.

2. The power supply device of claim 1, wherein the spring increases the spring force against the at least one battery cell when one or more battery cells of the cell bank swells during operation of the battery cells.

3. The power supply device of claim 1, wherein each battery cell comprises a respective portion of thermal interface material to transfer heat from a respective battery cell, the heat generated during operation of the respective battery cell.

4. The power supply device of claim 3, wherein a first respective portion of thermal interface material disposed on a surface of a first respective battery cell faces a second respective portion of thermal interface material disposed on a surface of a second respective battery cell adjacent to the first respective battery cell.

5. The power supply device of claim 1, wherein each respective recess of the plurality of recesses for the first cell frame corresponds to a single battery cell.

6. The power supply device of claim 1, wherein the plurality of recesses align the battery cells with weld straps at the first cell frame section or the second cell frame section, the weld straps defining the conductive connector.

7. The power supply device of claim 1, wherein the serpentine path of the vapor chamber (i) contacts a first surface of a first battery cell of the battery cells, (ii) does not contact the first battery cell as the serpentine path extends between the first battery cell and an adjacent second battery cell of the battery cells, and (iii) contacts a second surface of the adjacent second battery cell, the second surface of the adjacent second battery cell opposite the first surface of the first battery cell.

8. The power supply device of claim 1, wherein the recesses of the first cell frame section align the battery cells of a respective cell bank in a row pattern, the row pattern comprising a first battery cell of the battery cells and a second battery cell of the battery cell spaced apart by (i) a first portion of the thermal interface material corresponding to and in contact with the first battery cell, (ii) a second portion of the thermal interface material corresponding to and in contact with the second battery cell, and (iii) the vapor chamber extending between the first battery cell and the second battery cell along the serpentine path.

9. The power supply device of claim 8, wherein the serpentine path of the vapor chamber contacts the first battery cell on a first side without the first portion of the thermal interface material and contacts the second battery cell on a second side without the second portion of the thermal interface material and opposite the first side of the first battery cell.

10. The power supply device of claim 1, wherein the thermal interface material contacts a middle portion of each battery cell, the middle portion of each battery cell being between a first end portion and a second end portion of a respective battery cell.

11. The power supply device of claim 10, wherein the thermal interface material is configured to maintain contact with the middle portion of each battery cell by flexing in response to the battery cells expanding over time.

12. The power supply device of claim 1, wherein the plurality of recesses of the first cell frame section engage a first end of the battery cells, and wherein the second cell frame section comprises a second plurality of recesses that engage a second end of the battery cells opposite to the first end of the battery cells.

13. The power supply device of claim 1, further comprising a heat sink that extends across the first cell frame section and the second cell frame section to contact the vapor chamber and to transfer heat from the vapor chamber to the heat sink, the heat sink inserted through a notch in the enclosure to transfer heat to an environment outside of the power supply device.

14. The power supply device of claim 1, wherein the enclosure is a watertight sealed enclosure.

15. The power supply device of claim 1, wherein the one or more portions of thermal interface material compress in response to the battery cells expanding at a midsection of the battery cells over time.

16. The power supply device of claim 1, wherein the serpentine path partially surrounds each battery cell of the battery cells.

17. The power supply device of claim 16, wherein the partial surrounding of each battery cell exposes a surface of each battery cell to an area devoid of both the vapor chamber and thermal interface material.

18. The power supply device of claim 1, wherein the spring is integrated into at least one of the first cell frame section or the second cell frame section.

19. The power supply device of claim 1, wherein the serpentine path of the vapor chamber extends along a midsection of each battery cell, the midsection spaced apart from the first cell frame section and the second cell frame section.

20. The power supply device of claim 1, wherein the vapor chamber is not in direct contact with a surface of any battery cell as the vapor chamber extends along the serpentine path between the battery cells that generate the combined power output.