DE102022209944A1 - Battery cell housing - Google Patents

Abstract

A battery cell housing for a battery cell (2) for a motor vehicle for accommodating an electrically active material (3) of the battery cell (2) is proposed, wherein the battery cell housing (1) is closed and the battery cell housing (1) has an at least partially circumferential opening area (7). has, wherein the opening area (7) is designed to be pried open non-destructively or substantially non-destructively to form a removal opening (11) for the active material (3).

Description

The invention relates to a battery cell housing for a battery cell for a motor vehicle for receiving an electrical active material of the battery cell, a battery cell for a battery with a battery cell housing, a motor vehicle with a battery, a method for producing a battery cell and a method for opening the battery cell.

Current developments in the automotive industry and the electronics industry in general show a constantly growing demand for battery cells in order to be able to cover the growing need for electromobility or electronic devices. In order to be able to cover the need for raw materials or individual components, as in the US 20130059181 shown, cell lid made of composite material. These can be opened and closed using a tool and open when there is excess pressure inside the cell and burn in the event of a fire.

However, there are also calls for the environment to be less polluted. Currently, the battery cell casings, which are usually permanently closed by welding, are completely shredded, which means that there is no separation of the battery cell casing and the active material. This has a negative impact on the reprocessing and value chain of both the active material and the material of the battery cell housing.

It is therefore an object of the present invention to at least partially overcome at least one of the disadvantages described above. In particular, it is the object of the invention to easily optimize the reprocessing and value chain of materials of a battery cell.

The above object is achieved by a battery cell housing with the features of independent patent claim 1, by a battery cell with the features of independent patent claim 10, by a motor vehicle with the features of independent patent claim 11 and by a method with the features of independent patent claim 12. Further Features and details of the invention emerge from the subclaims, the description and the drawings. Features and details that are described in connection with the battery cell housing according to the invention naturally also apply in connection with the battery cell according to the invention and/or in connection with the motor vehicle according to the invention and/or in connection with the method according to the invention and vice versa, so with regard to the disclosure reference is or can always be made to the individual aspects of the invention.

According to the invention, a battery cell housing is provided for a battery cell for a motor vehicle to accommodate an electrical active material of the battery cell, the battery cell housing being closed and the battery cell housing having an at least partially circumferential opening area, the opening area being designed to form a removal opening for the active material non-destructively or to be pried open essentially non-destructively.

The electrical active material inside the battery cell housing of the battery cell can be a cell stack or a cell coil. The battery cell housing is optimally adapted to the dimensions of the cell stack or cell coil. To electrically contact the active material with the battery cell housing, terminals can be provided for the anode and the cathode. However, it is also conceivable that a terminal is only provided for the anode, in which case the cathodic potential is on a housing.

The opening area is an area of the battery cell housing that can be pried open non-destructively. Prying it open can be done, for example, with a tool. In the present case, at least partially circumferential is understood to mean that the opening area follows the shape of the battery cell housing to a certain extent or completely. It can follow the circumference of the battery cell housing and/or a longitudinal extent and/or a width extent. The course of the opening area is such that it forms a removal opening when it is torn open. This removal opening enables the removal of the active material and the electrolyte, which means that the removal opening is so large that the cell coil or cell stack and the electrolyte can be easily removed from the battery cell housing. This allows the different materials of the active material and the housing to be separated after the battery cell has been used.

At the same time, the opening area is safety-relevant and serves as a defined burst line. The opening area is designed so that it can withstand an internal gas pressure of 6 to 12 bar, preferably 8 to 10 bar. If there is a higher internal gas pressure in the battery cell due to chemical reactions or overheating, the battery cell housing can burst along the defined breaking point, i.e. the bursting line. Due to the dual function of the Opening area can therefore be dispensed with the bursting membrane. However, it is conceivable to provide these additionally.

In the present case, the opening area can be pried open non-destructively or essentially non-destructively. This means that minor plastic and/or elastic deformations of the opening area can occur when it is pried open, but the opening area can be reclosed, and that the required properties, such as pressure resistance or tightness, of the battery cell housing are met even when reclosed several times. This makes it possible to reuse the battery cell housing by simply subjecting it to a cleaning process. This has a particularly lasting effect on the value chain of the battery cell housing and at the same time protects the climate, as no complex reprocessing processes in the sense of metal processing are necessary.

Within the scope of the invention, it can be advantageous that the opening region has a first opening section and a second opening section, the first opening section and the second opening section being connected in a form-fitting and/or non-positive manner.

The positive connection is created by the engagement of the first opening section in the second opening section or the second opening section in the first opening section. As a result, the opening sections cannot come loose even without or when power transmission is interrupted. In other words, with a positive connection, one opening section is in the way of the other opening section. Under operating load, the compressive forces act normally, that is to say at right angles to the surfaces of the first and second opening sections.

The positive connection and/or frictional connection ensures that the opening area of the closed battery cell housing remains closed in order to withstand the internal pressure and ensure safe function. The positive connection and/or force connection of the first opening section with the second opening section provides a simple closure of the battery housing, which at the same time can be easily opened to form the removal opening.

In order to be able to reliably form a positive connection and/or frictional connection, it is advantageous if one of the opening sections is larger than the other opening section.

Within the scope of the invention, it is conceivable that the first opening section has an at least partially circumferential first surface and the second opening section has an at least partially circumferential second surface, the second surface and the first surface being arranged in a form-fitting and/or force-fitting manner relative to one another.

The positive and/or non-positive arrangement of the first surface of the first opening section to the second surface of the second opening section ensures the functionality of the battery housing. Accordingly, the connection can ensure that the battery cell housing and the connection can withstand an internal gas pressure of 6 - 12 bar, preferably 8 - 10 bar. At the same time, the leverage effect for prying open the opening area, i.e. levering open the first opening section along the second section or vice versa, can be accomplished in a simple manner.

It can be provided within the scope of the invention that the first opening section has an at least partially circumferential third surface and the second opening section has an at least partially circumferential fourth surface, the third surface and the fourth surface being arranged in a form-fitting and/or force-fitting manner relative to one another.

The first surface and third surface of the first opening section form a groove and the second surface and the fourth surface of the second opening section form a tongue. The spring engages in the groove and thus forms the positive and/or non-positive connection of the two opening sections.

The type of tongue-and-groove connection increases the security of the positive and/or non-positive connection, so that the battery cell housing can withstand an internal gas pressure of 6 - 12 bar, preferably 8 - 10 bar, without bursting. At the same time, this connection can still be easily pry open to form the removal opening for the active material.

It is conceivable according to the invention that a cell cup and at least one cell lid are provided, with the cell cup and the at least one cell lid being connected to one another in a connection area and with the at least one cell lid having the opening area.

The connection area can be created by plastic deformation, for example by crimping, or by a joining process, for example welding. This simplifies manufacturing and reduces manufacturing costs. For even more efficient and easy separation of cell cups and cell lids, it is advantageous if the cell cup has two opposite cell lids that can be levered open.

For electrical contacting of the electrical active material with a battery cell, at least one terminal is provided on the battery cell housing, preferably on the at least one cell cover. This is used to make contact with the anode. Either the battery cell housing or an additional terminal can be used for the cathodic potential. Both the cell cup and the cell lid are made of aluminum.

It is also conceivable that the opening area is at a distance from the connection area, the distance being 0.5 - 6 mm, preferably 1 - 5 mm.

The distance ensures that the connection holds in the connection area and is also tight and is not weakened by the opening area. This increases the safety of the battery cell housing in use and allows it to be easily opened for a recycling process. The distance is chosen so that the resulting removal opening is large enough to remove the active material.

Furthermore, it is conceivable that the connection area is used as a support when levering open the opening area; The distance is therefore chosen so that the force application points ensure simple and easy prying open.

Within the scope of the invention, it is optionally possible for the at least one cell cover to have an outer cell cover ring and an inner cell cover, the outer cell cover having the first opening section and the inner cell cover having the second opening section.

The cell cover ring corresponds to the shape of the battery cell housing and is not defined as annular in the sense of a radius. The cell cover ring determines the shape and size of the removal opening.

The division of the cell lid makes it possible to create a secure connection area between the cell cup and the outer cell lid ring and at the same time to enable a secure opening area between the outer cell lid ring and the inner cell lid.

The outer cell cover ring has the first surface of the first opening section and the inner cell cover has the second surface of the second opening section. Furthermore, it is possible for the cell cover ring to have the third surface of the first opening section and the inner cell cover to have the fourth surface of the opening section.

Furthermore, it can be provided within the scope of the invention that a sealant is provided in the connection area and/or in the opening area, the sealant being designed to withstand an internal gas pressure of 6 - 12 bar, preferably 8 - 10 bar.

A sealant can increase safety by providing additional protection against the leakage of active material and electrolyte from the battery cell housing and against the entry of air into the battery cell housing. The seal can be plastically deformed in the connection area or can be a clamped or glued-in O-ring. By means of a seal in the area of the opening area, in particular between the first opening section and the second opening section, it is possible to reduce the material thickness therein, since bursting is prevented by the seal; At the same time, the battery cell housing can be opened more easily.

The seal between the first and second opening sections can be arranged between the first surface and the second surface and/or between the third and fourth surfaces.

In relation to the present invention, it is conceivable that the sealant is made of plastic, preferably polypropylene. This is easy to handle as it can be easily deformed or glued in and has an increased sealing effect.

The above object is further achieved by a battery cell according to the invention for a battery with a battery cell housing described above, the battery cell housing being filled with an electrical active material.

The battery cell can be easily recycled due to its battery cell housing. Since the battery cell housing can be opened in a simple manner, the active material and the electrolyte can be easily removed through the removal opening and both the housing and the removed material can be fed into a reprocessing process.

The above object is further achieved by a motor vehicle according to the invention with a battery comprising at least one battery cell with the above-mentioned features and advantages.

• - durch Aufbringen einer Kraft, insbesondere einer Hebelkraft, der Öffnungsbereich zur Entnahme des Aktivmaterials geöffnet wird, und wobei
• - das elektrische Aktivmaterial aus dem Zellbecher entfernt wird, und wobei
• - das elektrische Aktivmaterial seinem Recycelprozess zugeführt wird und wobei
• - der Zelldeckel und der Zellbecher zur Wiederverwendung gereinigt werden.

The above object is further achieved by a method according to the invention for opening a battery cell housing described above of a battery cell described above, wherein

• - by applying a force, in particular a lever force, the opening area is opened for removing the active material, and where
• - the electrically active material is removed from the cell cup, and where
• - the electrical active material is fed to its recycling process and whereby
• - the cell lid and the cell cup are cleaned for reuse.

It is particularly advantageous if the battery cell housing provided has the properties described above. It is particularly advantageous if a battery cell housing comprises a cell cup and at least one cell cover. The opening area, which is preferably located in the cell lid, can then be levered open by means of a force, thereby forming the removal opening. It is advantageous here if the cell lid has an outer cell lid ring and an inner cell lid in order to be able to pry open the inner cell lid.

Within the scope of the invention, it can be advantageous that a lever tool is provided, with the battery cell housing being levered open by means of the lever tool at the at least partially circumferential opening area.

By using a lever tool, the forces to be applied can be reduced, so that the force required is reduced. By choosing the right tool, plastic deformation can then be reduced or essentially prevented.

• 1 schematische Darstellung eines erfindungsgemäßen Batteriegehäuses,
• 2 schematische Darstellung eines geöffneten Zellbechers eines Batteriezellgehäuses,
• 3 schematische Darstellung eines ersten Öffnungsbereiches des Batteriegehäuses,
• 4 schematische Darstellung eines zweiten Öffnungsbereiches des Batteriegehäuses,
• 5 Flow-Chart eines Herstellungsverfahrens für eine Batteriezelle.

Further advantages, features and details of the invention emerge from the following description, in which several exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can be essential to the invention individually or in any combination. The invention is shown in the following figures:

• 1 schematic representation of a battery housing according to the invention,
• 2 schematic representation of an opened cell cup of a battery cell housing,
• 3 schematic representation of a first opening area of the battery housing,
• 4 schematic representation of a second opening area of the battery housing,
• 5 Flow chart of a manufacturing process for a battery cell.

The 1 shows the battery cell housing 1 for a battery cell 2 for a motor vehicle to accommodate an electrical active material 3 of the battery cell 2. This has a closed battery cell housing 1, consisting of a cell cup 4 and a cell cover 5. The cell cover 5 has a terminal 6 for contacting the anode , the potential of the cathode is present on the battery cell housing 1. For further processing or reuse, the battery cell housing 1 is opened in the opening area 7 and forms, as in 2 shown, the removal opening 11, in order to be able to remove the active material 3, i.e. the cell stack 8 or cell coil 9, and the electrolyte 10 through this. The opening area 7 is designed to be circumferential and designed to be pried open non-destructively or essentially non-destructively to form the removal opening 11 for the active material 3.

In order to ensure that the battery cell housing 1 is safe when closed, that is, can withstand an internal gas pressure of 6 - 12 bar and can be easily pried open, the cell cover 5 has an outer cell cover ring 12 and an inner cell cover 13, with the outer cell cover being the first Opening section 14 and the inner cell cover 13 has the second opening section 15 (see 3 and 4 ). The first opening section 14 and the second opening section 15 are connected in a form-fitting and non-positive manner.

In the first exemplary embodiment according to 3 the first opening section 14 has a circumferential first surface 16 and the second opening section 15 has an at least partially circumferential second surface 17. The second surface 17 and the first surface 16 are arranged in a form-fitting and non-positive manner relative to one another.

In the second exemplary embodiment according to 4 the first opening section 14 has a circumferential third surface 18 in addition to the circumferential first surface 16 and the second opening section 15 has a circumferential fourth surface 19 in addition to the circumferential second surface 17. The third surface 18 and the fourth surface 19 are also arranged in a form-fitting and non-positive manner relative to one another. The second exemplary embodiment shows here that the first surface 16 and the third surface 18 of the first opening section 14 form a groove and the second surface 17 and the fourth surface 19 of the
second opening section 15 form a spring. When closed, the spring sits positively and non-positively in the groove and forms a secure closure that can be easily levered open to form the removal opening 11.

For a secure connection of the cell cover 5 or the outer cell cover ring, the opening area 7 is arranged at a distance from the connection area 20. The distance between the connection area 20 and the opening area 7 is between 1.5 and 5 mm. The connection area 20 connects the cell cover 5 with the cell cup 4. According to 3 and 4 the connection area 20 is crimped.

In order to ensure that electrolyte 10 does not escape or air enters either in the connection area 20 or in the opening area 7 of the battery cell housing, a sealant 21 is provided in each case. This is in 3 the sealant 21 between the first surface 16 of the first opening section and the second surface 17 of the second opening section 15, and in 4 the sealant 21 is provided between the third surface 18 of the first opening section 14 and the fourth surface 19 of the second opening section 15. The sealant 21 is made of polypropylene and is designed to withstand an internal gas pressure of 6 to 12 bar, preferably 8 to 10 bar.

In 5 the method 100 for opening a described battery cell housing 1 of a battery cell 2 is shown. In a first step, a force is applied 110 in such a way that the opening area 7 is opened for the removal 120 of the active material 3 by the resulting lever. Finally, the electrically active material 3 is removed from the cell cup 4 and the electrically active material 3 is sent to its recycling process 130. At the same time, the cell cover 5 and the cell cup 4 are cleaned for reuse 140.

The force can be applied particularly easily using a lever tool 22. The battery cell housing 1 is levered open using the lever tool 22 at the at least partially circumferential opening area 7.

Reference symbol list

1

Battery cell housing

2

Battery cell

3

Active material

4

cell cup

5

Cell cap

6

terminal

7

Opening area

8th

Cell stack

9

cell wrap

10

electrolyte

11

removal opening

12

outer cell cover ring

13

inner cell cover

14

first opening section

15

second opening section

16

first surface

17

second area

18

third area

19

fourth area

20

Connection area

21

sealant

22

Pry tool

100

Proceedings

110

Applying the force

120

withdrawal

130

Respectively

140

Clean

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 20130059181 [0002]

Claims (13)

Battery cell housing for a battery cell (2) for a motor vehicle for receiving an electrical active material (3) of the battery cell (2), the battery cell housing (1) being closed and the battery cell housing (1) having an at least partially circumferential opening region (7), the Opening area (7) is designed to be pried open non-destructively or substantially non-destructively to form a removal opening (11) for the active material (3). Battery cell housing Claim 1 , characterized in that the opening region (7) has a first opening section (14) and a second opening section (15), the first opening section (14) and the second opening section (15) being connected in a form-fitting and/or non-positive manner. Battery cell housing Claim 1 or 2 , characterized in that the first opening section (14) has an at least partially circumferential first surface (16) and the second opening section (15) has an at least partially circumferential second surface (17), the second surface (17) and the first surface ( 16) are arranged in a form-fitting and/or force-fitting manner to one another. Battery cell housing according to one of the preceding claims, characterized in that the first opening section (14) has an at least partially circumferential third surface (18) and the second opening section (15) has an at least partially circumferential fourth surface (19), the third surface (18 ) and the fourth surface (19) are arranged in a form-fitting and/or non-positive manner to one another. Battery cell housing according to one of the preceding claims, characterized in that a cell cup (4) and at least one cell cover (5) are provided, the cell cup (4) and the at least one cell cover (5) being connected to one another in a connection region (20), and wherein the at least one cell cover (5) has the opening area (7). Battery cell housing according to one of the preceding claims, characterized in that the opening area (7) is at a distance from the connection area (20), the distance being 0.5 - 6 mm, preferably 1 - 5 mm. Battery cell housing according to one of the preceding claims, characterized in that the at least one cell cover (5) has an outer cell cover ring (12) and an inner cell cover (13), the outer cell cover having the first opening section (14) and the inner cell cover (13) has the second opening section (15). Battery cell housing according to one of the preceding claims, characterized in that a sealant (21) is provided in the connection area (20) and/or in the opening area (7), the sealant (21) being designed to withstand an internal gas pressure of 6 to 12 bar. preferably 8 to 10 bar. Battery cell housing according to one of the preceding claims, characterized in that the sealing means (21) is made of plastic, preferably polypropylene. Battery cell for a battery with a battery cell housing (1) according to one of Claims 1 until 9 , wherein the battery cell housing (1) is filled with an electrical active material (3). Motor vehicle with a battery comprising at least one battery cell (2) according to Claim 10 . Method for opening a battery cell housing (1) according to one of Claims 1 until 9 a battery cell (2). Claim 10 , wherein - by applying a force, in particular a lever force, the opening area (7) is opened for the removal (120) of the active material (3), and wherein - the electrical active material (3) is removed from the cell cup (4), and where - the electrical active material (3) is fed to its recycling process and wherein - the cell cover (5) and the cell cup (4) are cleaned for reuse. Procedure according to Claim 12 , characterized in that a lever tool (22) is provided, the battery cell housing (1) being levered open by means of the lever tool (22) at the at least partially circumferential opening area (7).

Images