Cooling circuit with cooling fluid for lithium batteries, and a vehicle comprising said cooling circuit

Patent metadata

Field	Value
Publication number	US-10135103-B2
Application number	US-201615052036-A
Country	US
Kind code	B2
Filing date	Feb 24, 2016
Priority date	Feb 26, 2015
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

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. The cells are perimetrically delimited by external walls. At least one bag contains cooling liquid associated in contact with the outer walls of the cells. The bag is made of deformable plastic material so as to be counter-shaped to the outer walls to adhere perimetrally to the outer walls and the circuit provides forced circulation of the cooling liquid through said at least one bag.

First claim

The invention claimed is:

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,
circulation member that acts to force the cooling fluid through said at least one bag,
wherein spacers are arranged between the cells adjacent to each other, said spacers acting to create 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 the bag is not compressed between adjacent cells,
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, and
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.

2. The cooling circuit as set forth in claim 1 , wherein the bag comprises gaps, without liquid surrounding the spacers so as not to subject the bag to any compression by the cells packed together.

3. The cooling circuit as set forth in claim 1 , wherein the bag is at least partially attached to the outer walls by interposed thermally conductive adhesives.

4. The cooling circuit as set forth in claim 1 , wherein the thickness of the material composing said bag is between 50 and 350 microns.

5. The cooling circuit as set forth in 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. The cooling circuit as set forth in claim 1 , wherein said bag has a tubular conformation so as to be folded and wrapped around the outer walls of said cells.

7. The cooling circuit as set forth in claim 1 , wherein said connecting elements are thermally conductive so as to facilitate heat dissipation from the cells to the cooling fluid.

8. The cooling circuit as set forth in claim 1 , wherein the connecting elements are attached to the outer walls of the cells by thermally conductive adhesives.

9. The cooling circuit as set forth in claim 1 , wherein the connecting elements are positioned in the vicinity of curved portions of the bag around the outer walls of the cells.

10. The cooling circuit as set forth in claim 1 , wherein the outer walls of at least one cell are provided with cooling fins.

11. The cooling circuit as set forth in claim 10 , wherein at least one bag is applied in contact with at least one cooling fin.

12. The cooling circuit as set forth in claim 1 , wherein the circuit comprises a plurality of bags, each associated with a cell, said bags being fluidically connected to each other.

13. The cooling circuit as set forth in claim 1 , wherein the circuit comprises at least one bag associated with a plurality of cells.

14. The cooling circuit as set forth in claim 1 , wherein the outer walls comprise bottom walls and 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.

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

16. 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,
a circulation member that acts to force the cooling fluid through said at least one bag, said circulation member including, 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, said flexible lung including 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, and
wherein spacers are arranged between the cells adjacent to each other, said spacers acting to create 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 the bag is not compressed between adjacent cells.

17. 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,
a circulation member that acts to force the cooling fluid through said at least one bag, said circulation member including, 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, said flexible lung including 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 an elastic membrane such as springs and/or pressurised fluids, and
wherein spacers are arranged between the cells adjacent to each other, said spacers acting to create 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 the bag is not compressed between adjacent cells.

Assignees

• Magneti Marelli Spa

Inventors

• Ciampolini Franco
• Suglia Rosanna
• Pritelli Danilo
• Aurilio Gianluca

Classifications

• H01M10/613 Primary

  Cooling or keeping cold · CPC title

• H01M10/6568 Primary

  characterised by flow circuits, e.g. loops, located externally to the cells or cell casings · CPC title

• H01M10/6565

  with recirculation or U-turn in the flow path, i.e. back and forth · CPC title

• H01M10/052

  Li-accumulators · CPC title

• B60L58/26

  by cooling · CPC title