EP-4738442-A1 - PRE-CALENDERING SYSTEM FOR REDUCING STRAIN IMBALANCES IN MULTILANE ELECTRODES

Abstract

Generally described, one or more aspects of the present disclosure relate to methods, systems, and devices related to pre-straining bare lanes of a multilane electrode with a system for calendering a multilane electrode including a pre-strain roll device including a plurality of pre-strain rollers and a pressure roller forming a pre-strain nib and a calender roll device comprising a pair of calendering rollers forming a calendering nip positioned downstream from the pre-strain roll device.

Inventors

• MUTHUKUMAR, SIVA RAM KUMAR
• YANG, XIAOYUN
• ZHU, YAOYAO
• LV, Kezhou

Assignees

• Tesla, Inc.

Dates

Publication Date

20260506

Application Date

20251016

Claims (15)

1. A system for calendering a multilane electrode, comprising: a pre-strain roll device comprising a plurality of pre-strain rollers and a pressure roller, wherein the plurality of pre-strain rollers and the pressure roller form a pre-strain nib; and a calender roll device comprising a pair of calendering rollers forming a calendering nib positioned downstream from the pre-strain roll device.
2. The system of Claim 1, further comprising a multilane electrode comprising a plurality of electrode films and a plurality of bare lanes positioned within the pre-strain nib and the calendering nib.
3. The system of Claim 1 or 2, further comprising a driving pressure roller contacting the pressure roller.
4. The system of any one of Claims 1-3, wherein the plurality of pre-strain rollers are configured to be driven by the pressure roller.
5. The system of any one of Claims 1-4, wherein the pressure roller is configured to press against the plurality of pre-strain rollers with a pressure of at least about 0.11 T/mm.
6. The system of Claim 1-5, wherein the calender roll device is configured to provide a pressure of at least about 0.25 T/mm.
7. The system of Claim 1-6, wherein each of the pair of pre-strain rollers comprises a cylindrical surface positioned tangential to a cylindrical surface of the pressure roller, preferably wherein each of the pair of pre-strain rollers comprises a chamfer at each end of the cylindrical surface.
8. The system of Claim 1-7, wherein the pair of pre-strain rollers are heated.
9. The system of Claim 1-8, wherein the plurality of pre-strain rollers comprise a stainless steel alloy material, and/or wherein each of the pair of pre-strain rollers comprise a surface coating.
10. A method of manufacturing a multilane electrode for an energy storage device, comprising: pre-strain calendering a multilane electrode comprising a plurality of bare lanes and a plurality of electrode films, wherein pre-strain calendering the multilane electrode comprises straining the plurality of bare lanes to form a pre-strained multilane electrode; and calendering the pre-strained multilane electrode to form a strain-balanced multilane electrode.
11. The method of Claim 10, wherein the multilane electrode further comprises a plurality of ceramic coated portions each positioned between each of the plurality of electrode films and each of the plurality of bare lanes, and/or wherein calendering the pre-strained multilane electrode occurs from a first end to a second end of the pre-strained multilane electrode.
12. The method of claim 10 or 11, wherein the strain-balanced multilane electrode comprises a camber of at most about 0.4 cm/m.
13. The method of any one of claims 10-12, further comprising forming the multilane electrode, preferably wherein the multilane electrode is formed via a wet process and/or wherein the multilane electrode is formed via a dry process.
14. A method of forming a plurality of electrodes, comprising: performing the method of any one of claims 10-13; and cutting along a length of each bare lanes to form a plurality of electrodes.
15. A method of forming an electrode assembly, comprising: the method of Claim 14; and disposing a separator between one of the plurality of electrodes and another electrode to form an electrode assembly; preferably wherein the one of the plurality of electrodes is a cathode.

Description

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS This application claims the benefit of priority to U.S. Patent Application No. 18/935,281, entitled "PRE-CALENDERING SYSTEM FOR REDUCING STRAIN IMBALANCES IN MULTILANE ELECTRODES," filed on November 1, 2024. BACKGROUND Field The present disclosure relates to devices, systems, and methods for calendering an electrode. More specifically, the present disclosure relates to pre-straining a multilane electrode prior to calendering the multilane electrode. Description of the Related Art Electrodes can be created using a wet or dry electrode manufacturing process. Conventional wet electrode processes involve mixing a slurry, coating a foil with the slurry, drying the slurry onto the foil, and then calendering the electrode. Electrodes can also be created using a dry electrode process by calendering a dry electrode film onto a foil. The calendering process can be prone to quality issues, such as introducing electrode camber and creasing. Accordingly, there is a need for devices, systems, and methods for reducing quality issues during the production of electrodes. SUMMARY For purposes of summarizing the embodiments and the advantages achieved over the prior art, certain objects and advantages of the embodiments are described herein. Not all such objects or advantages may be achieved in any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the design may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. In some aspects, a system for calendering a multilane electrode is described. The system comprising a pre-strain roll device comprising a plurality of pre-strain rollers and a pressure roller, wherein the plurality of pre-strain rollers and the pressure roller form a pre-strain nib; and a calender roll device comprising a pair of calendering rollers forming a calendering nip positioned downstream from the pre-strain roll device; a multilane electrode comprising a plurality of electrode films and a plurality of bare lanes positioned within the pre-strain nib and the calendering nib; wherein each of the plurality of pre-strain rollers is positioned adjacent to a portion of one of the plurality of bare lanes; and wherein the plurality of pre-strain rollers are configured to apply a force to the plurality of bare lanes. In some aspects, a system for calendering a multilane electrode is described. The system comprises a pre-strain roll device comprising a plurality of pre-strain rollers and a pressure roller, wherein the plurality of pre-strain rollers and the pressure roller form a pre-strain nib; and a calender roll device comprising a pair of calendering rollers forming a calendering nip positioned downstream from the pre-strain roll device. In some embodiments, the system further comprises a multilane electrode comprising a plurality of electrode films and a plurality of bare lanes positioned within the pre-strain nib and the calendering nib. In some embodiments, the system further comprises a driving pressure roller contacting the pressure roller. In some embodiments, the plurality of pre-strain rollers are configured to be driven by the pressure roller. In some embodiments, the pressure roller is configured to press against the plurality of pre-strain rollers with a pressure of at least about 0.11 T/mm. In some embodiments, the calender roll device is configured to provide a pressure of at least about 0.25 T/mm. In some embodiments, each of the pre-strain rollers comprises a cylindrical surface positioned tangential to a cylindrical surface of the pressure roller. In some embodiments, each of the pre-strain rollers comprises a chamfer at each end of the cylindrical surface. In some embodiments, the pre-strain rollers are heated. In some embodiments, the plurality of pre-strain rollers comprise a stainless steel alloy material. In some embodiments, the pre-strain rollers comprise a surface coating. In some aspects, a method of manufacturing a multilane electrode for an energy storage device is described. The method comprises pre-strain calendering a multilane electrode comprising a plurality of bare lanes and a plurality of electrode films, wherein pre-strain calendering the multilane electrode comprises straining the plurality of bare lanes to form a pre-strained multilane electrode; and calendering the pre-strained multilane electrode to form a strain-balanced multilane electrode. In some embodiments, the multilane electrode further comprises a plurality of ceramic coated portions each positioned between each of the plurality of electrode films and each of the plurality of bare lanes. In some embodiments, calendering the pre-strained multilane electrode occurs from a first end to a second end of the pre-strained multilane electrode. In some embod