Magnetically coated busbar tabs

Patent metadata

Field	Value
Publication number	US-10811663-B2
Application number	US-201715593705-A
Country	US
Kind code	B2
Filing date	May 12, 2017
Priority date	May 12, 2017
Publication date	Oct 20, 2020
Grant date	Oct 20, 2020

Abstract

Methods and systems for welding a terminal of a battery cell to corresponding terminal tab or busbar are described using a magnet that causes the terminal and tab/busbar to be placed in physical contact. The terminal of a battery cell is aligned in contact with the tab/busbar by the force of a magnetic field. A welder, e.g., a laser welder, can then generate a laser weld beam to weld the terminal of the battery cell to the tab/busbar. Next, the laser weld beam is narrowed, reducing the first diameter to a smaller second diameter. Without touching the tab/busbar or terminal of the battery (which could affect the welding operation), the magnetic field can cause a force that brings the tab and terminal in contact during welding.

First claim

What is claimed is:

1. A welding system, comprising:
a magnet within physical proximity to a tab, wherein the magnet emits a magnetic field that causes a magnetic force to be applied to the tab, wherein the tab comprises a first material that is electrically conductive and a second material that is magnetic;
a welder that welds the tab to a terminal of a battery cell;
a controller that:
presents the magnet in physical proximity to the tab to produce a magnetic force on the second material that causes the tab to come into physical contact with the terminal of the battery cell; and
while the magnetic force causes the tab to come into physical contact with the terminal of the battery cell, activates the welder to weld the tab to the terminal of the battery cell.

2. The welding system of claim 1 , wherein the welder is a laser welding system, and wherein the controller activates a laser produced by the laser welding system to weld the tab to the terminal of the battery cell.

3. The welding system of claim 2 , wherein the second material is at least one of neodymium, iron, nickel, cobalt, montmorillonite, nontronite, biotite siderite(carbonate), pyrite, magnetite, hematite, ulvospinel, ilmenite, maghemite, jacobsite, trevorite, magnesioferrite, pyrrhotite, greigite, troilite, goethite, lepidocrocite, feroxyhyte, awaruite, and/or wairauite.

4. The welding system of claim 3 , wherein the first material is at least one of copper, aluminum, gold, silver, platinum, iron, zinc, and/or nickel.

5. The welding system of claim 4 , wherein the second material envelopes the first material.

6. The welding system of claim 5 , wherein the second material coats the first material by hot dipping the first material into a molten first material.

7. The welding system of claim 4 , wherein the second material is joined to the first material by at least one of welding, brazing, hot dipping, and/or adhering.

8. The welding system of claim 1 , wherein the first material is made magnetic by introducing ions of the second material into the first material.

9. The welding system of claim 1 , wherein the second material is formed into an indention in the first material.

10. The welding system of claim 1 , wherein the tab comprises a third magnetic material joined to the first material.

11. A welding method, comprising:
providing a tab to be welded to a terminal of a battery cell, wherein the tab comprises a first material that is electrically conductive and a second material that is magnetic;
providing the battery cell comprising the terminal;
moving the tab or battery cell such that the tab is in physical proximity to the terminal of the battery cell;
providing a magnet;
when the tab is within physical proximity of the terminal of the battery cell, moving the magnet in physical proximity to the tab to produce a magnetic force on the second material that causes the tab to come into physical contact with the terminal of the battery cell; and
while the magnetic force causes the tab to come into physical contact with the terminal of the battery cell, activating, via a controller, a laser welder causing the laser welder to emit a laser weld beam that welds the tab to the terminal of the battery cell.

12. The welding method of claim 11 , wherein the second material coats the first material by hot dipping the first material into a molten first material.

13. The welding method of claim 11 , wherein the second material is joined to the first material by at least one of welding, brazing, hot dipping, and/or adhering.

14. The welding method of claim 11 , wherein the first material is made magnetic by introducing ions of the second material into the first material.

15. The welding method of claim 11 , wherein the tab comprises a third magnetic material joined to the first material and/or second material.

16. A method of manufacturing a tab that is laser welded to a battery cell to form a busbar connection, comprising:
forming a tab comprising:
providing a first material, wherein the first material is electrically conductive;
providing a second material, wherein the second material is magnetic; and
joining the first material to the second material.

17. The method of manufacturing of claim 16 , further comprising:
providing the tab to be welded to a terminal of the battery cell;
providing the battery cell comprising the terminal;
moving the tab or battery cell such that the tab is in physical proximity to the terminal;
providing a magnet;
when the tab is within physical proximity of the terminal, moving the magnet in physical proximity to the tab to produce a magnetic force on the second material that causes the tab to come into physical contact with the terminal of the battery cell; and
while the magnetic force causes the tab to come into physical contact with the terminal of the battery cell, activating, via a controller, a laser welder causing the laser welder to emit a laser weld beam that welds the tab to the terminal.

18. The method of manufacturing of claim 17 , wherein the joining comprises at least one of welding, brazing, hot dipping, and/or adhering.

19. The method of manufacturing of claim 17 , further comprising, after joining the first material to the second material, bending the tab to form an attachment portion.

20. The method of manufacturing of claim 17 , further comprising joining a third magnetic material to the first material and/or the second material.

Assignees

• Nio Usa Inc

Inventors

• Newman Austin L
• Smith Alexander J

Classifications

• H01M50/516

  by welding, soldering or brazing · CPC title

• H01M50/505

  comprising a single busbar · CPC title

• H01M50/566

  by welding, soldering or brazing · CPC title

• H01M50/562

  characterised by the material · CPC title

• H01M50/559

  Terminals adapted for cells having curved cross-section, e.g. round, elliptic or button cells (H01M50/553 takes precedence) · CPC title