COOLING CIRCUIT WITH COOLING FLUID FOR LITHIUM BATTERIES, AND A VEHICLE COMPRISING SAID COOLING CIRCUIT

• US 20160254577A1
• Filed: 02/24/2016
• Published: 09/01/2016
• Est. Priority Date: 02/26/2015
• Status: Active Grant

• Current Assignee: Magneti Marelli S.p.A.
• Original Assignee: Magneti Marelli S.p.A.
• Inventors: CIAMPOLINI, Franco, SUGLIA, Rosanna, PRITELLI, Danilo, AURELIO, Gianluca
• Granted Patent: US 10,135,103 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60L 58/26 by cooling
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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 10/486 for measuring temperature
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/63 Control systems charging or discharging in response to temperature H01M10/44 , H01M10/443; measurement of temperature H01M10/48 , H01M10/486
• CPC Class Codes: H01M 10/6551 Surfaces specially adapted for heat dissipation or radiation, e.g. fins or coatings
• CPC Class Codes: H01M 10/6557 arranged between the cells
• CPC Class Codes: H01M 10/6565 with recirculation or U-turn in the flow path, i.e. back and forth
• CPC Class Codes: H01M 10/6568 characterised by flow circuits, e.g. loops, located externally to the cells or cell casings
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• 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 cooling circuit with cooling liquid for lithium-ion batteries comprising a battery pack comprising a plurality of cells electrically connected with each other, suitable for powering an electric machine for traction, said cells being perimetrically delimited by external walls, at least one bag containing cooling liquid associated in contact with said outer walls of the cells. Advantageously, at least one bag is made of deformable plastic material so as to be counter-shaped to said outer walls to adhere perimetrally to said outer walls and the circuit comprises means of forced circulation of the cooling liquid through said at least one bag.

Claims

1. A cooling circuit with cooling fluid for lithium ion batteries comprising:

a battery pack comprising a plurality of cells electrically connected to each other, suitable for powering an electric machine for traction,

said cells being perimetrally delimited by outer walls,

at least one bag containing cooling fluid associated with contact with said outer walls of the cells,

wherein said at least one bag is made of electrically insulating and deformable material so as to be counter-shaped to said outer walls to adhere perimetrally to said outer walls,

forced circulation means of the cooling fluid through said at least one bag,

wherein between the cells adjacent to each other spacers are arranged which have the function of creating abutments for the packing of the cells composing the battery pack, wherein the bag interposed between adjacent cells has a thickness/shape less than that of an interspace between the adjacent cells, so that is not compressed between adjacent cells.

2. Cooling circuit according to claim 1, wherein the bag comprises gaps, i.e. portions without liquid surrounding the spacers so as not to subject the bag to any compression by the cells packed together.

3. Cooling circuit according claim 1, wherein the bag is at least partially attached to the outer walls by means of interposed thermally conductive adhesives.

4. Cooling circuit according to claim 1, wherein the thickness of the material composing said bag is between 50 and 350 microns.

5. Cooling circuit according to claim 1, wherein said bag comprises at least one internal path so as to create a circulation of the cooling fluid according to a predetermined path.

6. Cooling circuit according to claim 1, wherein said bag has a tubular conformation so as to be folded and wrapped around the outer walls of said cells.

7. Cooling circuit according to claim 1, wherein said bag is associated with a plurality of connecting elements suitable for performing an anchorage between the bag and the outer walls of the cells.

8. Cooling circuit according to claim 7, wherein said connecting elements are thermally conductive so as to facilitate heat dissipation from the cells to the cooling fluid.

9. Cooling circuit according to claim 7, wherein the connecting elements are attached to the outer walls of the cells by means of thermally conductive adhesives.

10. Cooling circuit according to claim 7, wherein the connecting elements are positioned in the vicinity of curved portions of the bag around the outer walls of the cells.

11. Cooling circuit according to claim 7, wherein the connecting elements are hollow bushings which are crossed by the cooling fluid which are arranged in direct contact with the outer walls of the cells, so as to allow, at the bushes, a direct contact between the coolant and the outer walls of the cells.

12. Cooling circuit according to claim 1, wherein the outer walls of at least one cell are provided with cooling fins.

13. Cooling circuit according to claim 12, wherein at least one bag is applied in contact with at least one cooling fin.

14. Cooling circuit according to claim 1, wherein the circuit comprises a plurality of bags, each associated with a cell, said bags being fluidically connected to each other.

15. Cooling circuit according to claim 1, wherein the circuit comprises at least one bag associated with a plurality of cells.

16. Cooling circuit according to claim 1, wherein the outer walls comprise bottom walls and/or top walls of the cells, wherein the bottom walls define a support surface of the cells and the top walls are opposite the bottom walls.

17. Cooling circuit according to claim 1, wherein said means for the forced circulation of cooling liquid comprise a flexible lung which pressurises the liquid inside said circuit, so as to favour contact between the cooling liquid and the outer walls of the cells.

18. Cooling circuit according to claim 17, wherein said flexible lung comprises a tubular elastic inserted around the bag which in turn envelops the battery pack or the individual cells so as to influence the bag in contact with said outer walls of the cells to be cooled.

19. Cooling circuit according to claim 17, wherein the flexible lung comprises a containment structure arranged around the bag so as to influence the bag in abutment against the outer walls of the cells to be cooled, wherein said containment structure encloses an elastic membrane which on the one hand interfaces with the bag and on the other is elastically influenced in compression against the bag by elastic means such as springs and/or pressurised fluids.

20. A vehicle comprising an electric machine for traction and a cooling circuit with cooling liquid for lithium ion batteries according to claim 1, wherein the electrical machine for traction is electrically connected to said lithium-ion batteries.