US-20260128390-A1 - Energy Storage Cell, Energy Storage Device, Motor Vehicle, and Method for Producing an Energy Storage Cell

Abstract

Energy storage cells are provided herein, the energy storage cells including a cell housing defining an inner region; an electrode assembly disposed in the inner region together with an electrolyte; and a support element disposed between a surface of the energy storage cell and at least one part of the electrode assembly, the support element contacting the surface and the at least one part; wherein the support element has a carrier part, and fill material held by the carrier part; and wherein the support element is configured to at least partially release the fill material to the electrolyte and to decrease in size in a direction transverse to the surface. Energy storage devices including the energy storage cells are further provided. Motor vehicles including the energy storage cells or energy storage devices are further provided. Methods for producing the energy storage cells are further provided.

Inventors

• Alexander Adam
• Nina Zensen

Assignees

• BAYERISCHE MOTOREN WERKE AKTIENGESELLSCHAFT

Dates

Publication Date

20260507

Application Date

20230906

Priority Date

20220929

Claims (20)

1. 1 - 12 . (canceled)
2. 13 . An energy storage cell, comprising: a cell housing defining an inner region of the energy storage cell; an electrode assembly disposed in the inner region together with an electrolyte; and a support element disposed between a surface of the energy storage cell and at least one part of the electrode assembly, the support element contacting the surface and the at least one part of the electrode assembly; wherein the support element has a carrier part, and fill material held by the carrier part; and wherein the support element is configured to at least partially release the fill material to the electrolyte and to decrease in size in a direction transverse to the surface.
3. 14 . The energy storage cell according to claim 13 , wherein the support element is clamped between the surface of the energy storage cell and the at least one part of the electrode assembly.
4. 15 . The energy storage cell according to claim 13 , wherein the carrier part has at least one shell that delimits an interior, and the fill material is at least partially contained in the interior.
5. 16 . The energy storage cell according to claim 15 , wherein the at least one shell is in the form of an elastic membrane.
6. 17 . The energy storage cell according to claim 15 , wherein the at least one shell is configured to open as a result of expansion of the electrode assembly in the direction transverse to the surface.
7. 18 . The energy storage cell according to claim 15 , wherein the support element is configured to at least partially release the fill material to the electrolyte through the at least one shell or upon opening of the at least one shell.
8. 19 . The energy storage cell according to claim 15 , wherein the interior is divided into at least a first chamber and a second chamber, and the fill material is at least partially contained in the first chamber and/or the second chamber.
9. 20 . The energy storage cell according to claim 13 , wherein the carrier part is porous at least sectionally.
10. 21 . The energy storage cell according to claim 13 , wherein the fill material is at least partially intercalated in pores of the carrier part.
11. 22 . The energy storage cell according to claim 13 , wherein the carrier part is fiber-reinforced.
12. 23 . The energy storage cell according to claim 13 , wherein the carrier part is in the form of a woven textile or in the form of a nonwoven textile, at least sectionally.
13. 24 . The energy storage cell according to claim 13 , wherein the fill material is at least partially soluble in the electrolyte and/or the fill material comprises a liquid or solid electrolyte additive, a lithium supporting electrolyte, a scavenger, and/or a reaction suppressor.
14. 25 . The energy storage cell according to claim 13 , wherein the surface of the energy storage cell is an inner face of the cell housing or a surface of a separator of the electrode assembly.
15. 26 . The energy storage cell according to claim 13 , wherein the surface of the energy storage cell is in planar contact with a side of the support element that is opposite the part of the electrode assembly.
16. 27 . The energy storage cell according to claim 13 , wherein the cell housing is rigid.
17. 28 . The energy storage cell according to claim 13 , which is a prismatic cell or a cylindrical cell.
18. 29 . The energy storage cell according to claim 13 , wherein an anode material of the electrode assembly contains silicon.
19. 30 . An energy store comprising at least one energy storage cell according to claim 13 .
20. 31 . A motor vehicle comprising an energy storage cell according to claim or an energy store comprising the energy storage cell.

Description

BACKGROUND AND SUMMARY The present disclosure relates to an energy storage cell, to an energy store comprising the energy storage cell, to a motor vehicle comprising the energy storage cell or the energy store, and to a method for producing the energy storage cell. Modern energy storage cells for motor vehicle traction batteries, for example rechargeable lithium-ion batteries (also referred to as secondary lithium-ion batteries in the literature), generally have an electrode assembly which comprises an anode, a cathode, and, disposed between the cathode and the anode, a separator and which is disposed together with an electrolyte in a cell housing of the energy storage cell. The anode and the cathode each comprise an electrode which is usually metallic (copper, for example, on the anode side; aluminum, for example, on the cathode side) and which is coated with an active material (graphite, for example, on the anode side; lithium cobalt oxide or lithium manganese oxide, for example, on the cathode side). The cell housing, also referred to as a can in the case of cylindrical energy storage cells, may be coated with an insulator on the outside. The separator is intended to be ion-conductive (in particular, pervious to lithium ions), but otherwise electrically insulates the anode from the cathode. Over the lifetime of such energy storage cells, the electrode assembly, in particular the active material on the anode side, can swell with each charge cycle. The size of the cell housing of the energy storage cell is therefore commonly chosen such that space is available for swelling of the electrode assembly. By contrast, the less space occupied by the electrode assembly in the cell housing (in other words, the lower the packing ratio of the energy storage cell), the more likely that deposition of lithium metal as sponge or dendrites (so-called lithium plating) may occur in the electrode assembly. To minimize lithium deposition, it is known from the art to subject the positive and/or negative electrode of a lithium cell to a corona treatment. In relation to this, document DE 10 2014 218 143A1, for example, discloses a method for producing a lithium cell, in which a particulate active material and a coating composition containing a binder are applied to a metal foil in order to form a positive/negative electrode. Thereafter, the positive/negative electrode is compressed. The separator is introduced between the electrodes, followed by filling a cell housing with a liquid electrolyte. Prior to wetting with the liquid electrolyte, the positive and/or negative electrode is subjected to corona treatment so that the liquid electrolyte will penetrate into the pores of the electrode. Against this background, it is an object of the present disclosure to provide an energy storage cell which has a long lifetime and can store energy reliably. It is a further object of the present disclosure to provide a corresponding energy store, a corresponding motor vehicle, and a corresponding method for producing an energy storage cell. This object is achieved by an energy storage cell according to the present disclosure, an energy store having the features provided in the present disclosure, a motor vehicle according to the present disclosure, and a method for producing an energy storage cell having the features provided in the present disclosure. The energy storage cell is preferably intended for a vehicle traction battery, for example a rechargeable lithium-ion battery (so-called secondary lithium-ion battery), and comprises a cell housing which defines an inner region of the energy storage cell, an electrode assembly which is disposed in the inner region together with an electrolyte, and a support element which is disposed between a surface of the energy storage cell and at least one part of the electrode assembly and which contacts the surface and the part of the electrode assembly. The support element has a carrier part and fill material held by the carrier part (at least temporarily, in particular in an initial state of the support element). Furthermore, the support element is configured to at least partially release the fill material to the electrolyte and, as a result, to decrease in size in a direction transverse to the surface, in other words, to shrink in a particular direction. The particular direction is preferably a radial direction of the energy storage cell. In other words, the support element can degrade and, in doing so, release a portion of the mass of the support element (or reduce the volume of the support element) to free space in the inner region of the cell housing for the electrode assembly, the electrode assembly being able to expand into said space under operating conditions. The swelling of the electrode assembly can therefore be compensated for. Accordingly, the energy storage cell can be produced with an initially relatively large effective packing ratio of support element and electrode assembly in relation to