Battery cell assembly

Abstract

A battery cell assembly includes a battery cell and a battery cell holder. The battery cell has a cell case. The unit case has a case surface. The outer housing surface has a first plurality of grooves formed therein. The battery cell holder has a plurality of cell pockets. Each unit pocket has a wall. The wall has a wall surface. The wall surface has a second plurality of grooves that interact with the first plurality of grooves on the outer surface of the unit case. The interaction of the first plurality of grooves on the cell case and the second plurality of grooves on the wall of each of the plurality of cell pockets collectively prevents movement of the battery cell relative to the battery cell holder.

Description

Technical Field

[0001] The present disclosure relates to a battery cell assembly, and more particularly to a battery cell assembly having a battery cell and a battery support structure. Background Art

[0002] A rechargeable energy storage system (RESS), such as a battery, typically includes one or more battery cells and a device for supporting or fixing the battery cells. A battery cell is typically composed of an anode material and a cathode material separated by an electrically insulating material. A battery may include many anode pairs and cathode pairs separated by insulating materials. In one example of a battery cell, the anode material, the separator material, and the cathode material (regardless of the number) are wound into a roll, which is sometimes referred to as a "jelly roll". The core package is then inserted into a hollow metal casing or enclosure to protect the core package from the surrounding environment. The casing is also used to contain an electrolyte within the casing and around the core package. The battery cell is supported by a housing or the like. Typically, an adhesive is used to secure the battery cell in the housing.

[0003] Battery cells in RESS may experience uncontrolled thermal events, known as thermal runaway propagation (TRP). During a TRP event, the temperature of the battery cells may increase, resulting in increased pressure. The increase in temperature and pressure within the enclosure due to gas generation may cause the enclosure seal to leak.

[0004] Although current RESS systems achieve their specific purposes, problems still exist. Therefore, there is a need for a new and improved RESS having a means for securing the battery cells in a support member or housing. In addition, there is a need for a RESS having a battery cell having a means for taking into account TRP events. Summary of the invention

[0005] According to several aspects of the present disclosure, a battery cell assembly is provided. The battery cell assembly includes a battery cell and a battery cell seat. The battery cell has a cell shell. The cell shell has a shell surface. The shell surface has a first plurality of grooves formed therein. The battery cell seat has a plurality of cell pockets. Each cell pocket has a wall. The wall has a wall surface. The wall surface has a second plurality of grooves that interact with the first plurality of grooves on the outer surface of the cell shell. The interaction of the first plurality of grooves on the cell shell with the second plurality of grooves on the wall of each of the plurality of cell pockets jointly prevents the battery cell from moving relative to the battery cell seat.

[0006] According to another aspect of the present disclosure, the battery cell assembly further includes a plurality of cooling channels, wherein each of the plurality of cooling channels is disposed in a wall of each of the plurality of cell pouches.

[0007] According to another aspect of the present disclosure, the battery cell assembly further includes a thermal interface material disposed between each of the plurality of cooling channels and an outer surface of a cell housing of the battery cell to facilitate heat transfer from the battery cell to the plurality of cooling channels.

[0008] According to another aspect of the present disclosure, the cell shell of the battery cell also includes a first end and a second end, wherein a first plurality of the first plurality of grooves are formed in the cell shell surface at the first end of the cell shell, and a second plurality of the first plurality of grooves are formed in the cell shell surface at the second end of the cell shell.

[0009] According to another aspect of the present disclosure, the unit housing further includes a first wall portion, wherein the first wall portion has a first wall thickness, wherein a first plurality of grooves are formed in the first wall portion.

[0010] According to another aspect of the present disclosure, the unit case further includes a second wall portion, wherein the second wall portion has a second wall thickness, wherein the second wall thickness is smaller than a first wall thickness of the first wall portion.

[0011] According to another aspect of the present disclosure, the second wall thickness of the second wall portion is provided at one of the first end and the second end of the unit case.

[0012] According to another aspect of the present disclosure, the wall of each unit bag in the plurality of unit bags has a first end and a second end, wherein a first plurality of a second plurality of grooves are formed on the wall surface at the first end of each unit bag in the plurality of unit bags, and a second plurality of the second plurality of grooves are formed on the wall surface at the second end of each unit bag in the plurality of unit bags.

[0013] According to another aspect of the present disclosure, the battery cell holder further includes a protrusion extending from one of the first end and the second end of the battery cell holder, wherein the protrusion and the end of the shell define a vent passage.

[0014] According to another aspect of the present disclosure, a battery cell assembly has a battery cell, a battery cell seat and a plurality of cooling channels. The battery cell has a cell shell. The cell shell has a shell surface, and the shell surface has a plurality of first grooves formed therein. The battery cell seat has a plurality of cell pockets. Each cell pocket has a wall, and the wall has a wall surface. The wall surface has a second plurality of grooves that interact with the first plurality of grooves on the outer surface of the cell shell. The interaction between the first plurality of grooves on the cell shell and the second plurality of grooves on the wall of each of the plurality of cell pockets jointly prevents the battery cell from moving relative to the battery cell seat. In addition, the battery seat also includes a plurality of cooling channels. Each of the plurality of cooling channels is disposed in the wall of each of the plurality of cell pockets.

[0015] According to yet another aspect of the present disclosure, the battery cell assembly further includes a thermal interface material disposed between each of the plurality of cooling channels and an outer surface of a cell housing of the battery cell to facilitate heat transfer from the battery cell to the plurality of cooling channels.

[0016] According to another aspect of the present disclosure, the cell shell of the battery cell further includes a first end and a second end. A first plurality of the first plurality of grooves are formed in the cell shell surface at the first end of the cell shell, and a second plurality of the first plurality of grooves are formed in the cell shell surface at the second end of the cell shell.

[0017] According to yet another aspect of the present disclosure, the unit housing further includes a first wall portion. The first wall portion has a first wall thickness, and a first plurality of grooves are formed in the first wall portion.

[0018] According to another aspect of the present disclosure, the cell housing further includes a second wall portion. The second wall portion has a second wall thickness, and the second wall thickness is less than the first wall thickness of the first wall portion. In addition, a portion of the cell housing, such as the bottom of the cell housing, is separated from the cell housing at the second wall thickness to release gas from the cell housing during an increase in the internal temperature of the battery cell, for example, during a TRP event.

[0019] According to still another aspect of the present disclosure, the second wall portion is provided at one of the first end and the second end of the unit case.

[0020] According to another aspect of the present disclosure, the wall of each of the plurality of unit bags has a first end and a second end. A first plurality of the second plurality of grooves are formed on the wall surface at the first end of each of the plurality of unit bags, and a second plurality of the second plurality of grooves are formed on the wall surface at the second end of each of the plurality of unit bags.

[0021] According to another aspect of the present disclosure, the battery cell holder further includes a protrusion extending from one of the first end and the second end of the battery cell holder, and the protrusion and the end of the shell define an exhaust gas channel.

[0022] According to another aspect of the present disclosure, a battery cell assembly has a battery cell, a battery cell seat and a plurality of cooling channels. The battery cell has a cell shell. The cell shell has a shell surface, and the shell surface has a first plurality of grooves formed therein. The cell shell has a first wall portion and a second wall portion, the first wall portion has a first wall thickness, and the first plurality of grooves are formed in the first wall portion. The second wall portion has a second wall thickness. The second wall thickness is less than the first wall thickness of the first wall portion. The battery cell seat has a plurality of cell pockets. Each cell pocket has a wall, and the wall has a wall surface. The wall surface has a second plurality of grooves that interact with the first plurality of grooves on the outer surface of the cell shell. The interaction of the first plurality of grooves on the cell shell with the second plurality of grooves on the wall of each of the plurality of cell pockets prevents the battery cell from moving relative to the battery cell seat. Each of the plurality of cooling channels is provided in the wall of each of the plurality of cell pockets.

[0023] According to another aspect of the present disclosure, the wall of each of the plurality of unit bags has a first end and a second end. A first plurality of the second plurality of grooves are formed on the wall surface at the first end of each of the plurality of unit bags. A second plurality of the second plurality of grooves are formed on the wall surface at the second end of each of the plurality of unit bags.

[0024] According to another aspect of the present disclosure, the battery cell holder further includes a protrusion extending from one of the first end and the second end of the battery cell holder, and the protrusion and the end of the shell define an exhaust gas channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

[0026] Figure 1 and Figure 2 are perspective and top views of a battery cell assembly according to the present disclosure;

[0027] Figure 3 According to the present disclosure, Figure 2 A cross-sectional view of a battery cell assembly is shown;

[0028] Figure 3A According to this disclosure Figure 3 an enlarged view of a first plurality of grooves formed in a housing surface and a plurality of grooves formed in a cell pocket wall; and

[0029] Figure 3B is an enlarged view of a second plurality of grooves formed in a housing surface and a second plurality of grooves formed on a wall surface at a second end of each of a plurality of unit pockets according to the present disclosure. DETAILED DESCRIPTION

[0030] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

[0031] Reference now Figure 1 and Figure 2 , showing a perspective view and a partial top view of a battery cell assembly 10 according to the present disclosure. The battery cell assembly 10 includes a battery cell 12 and a battery cell seat 14. Although only a partial view of the battery assembly 10 is shown, it will be understood by those of ordinary skill in the art that the battery assembly 10 having the features described below can be configured to have different sizes as required for a particular application. The battery cell 12 has a generally cylindrical shape and a hollow cylindrical cell shell 16. A core pack or Swiss roll design or assembly can be used to construct the battery cell 12, wherein an insulating sheet (not shown) is disposed on the surface, a thin layer of anode material (not shown) is placed on top of the insulating sheet, a separator (not shown) is placed on top of the anode material, and a cathode material (not shown) is placed on top of the separator. The core pack assembly forms a cylindrical rechargeable battery made of, for example, nickel cadmium (Ni-Cd), nickel metal hydride (NiMH), and lithium ion (Li-ion). The core pack assembly (not shown) is inserted into the hollow cylindrical cell shell 16. The cell shell 16 is sealed and metal contacts (not shown) are connected. For example, various devices including electric motors may be powered by the battery cell 12 by connecting wires from the devices (ie, the electric motors) to the metal contacts of the battery cell 12 .

[0032] Polymers such as nylon or other suitable materials can be used to construct or construct the battery holder 14. In addition, the battery holder 14 can be formed using polymers by any suitable manufacturing process, for example, injection molding, 3D printing, vacuum forming, etc. The battery cell holder 14 has a plurality of cell pockets 22. The cell pockets 22 are generally cylindrical in shape and are configured to hold one battery cell 12 in each cell pocket 22, as will be described in further detail below. More specifically, each cell pocket 22 has a pocket wall 24. The pocket wall 24 has a pocket wall surface 26. The pocket wall 24 and the pocket wall surface 26 are used to hold or support the battery cells 12 and cool the battery cells 12, as will be described in further detail below.

[0033] The battery cell holder 14 also includes a plurality of substantially flat and longitudinally extending cooling bands 32 for receiving the heat generated by the battery cell 12 and transferring it to a position outside the battery assembly 10. The cooling bands 32 extend through the entire length of the battery holder 14, and each cooling band extends or aligns adjacent to each cell bag 22. Each cooling band 32 is made of a thermally conductive material such as a metal. For example, the cooling band 32 is made of aluminum. During the molding process of the battery cell holder 14, the cooling band 32 can be insert molded or overmolded in the battery cell holder 14. However, the opening or window 33 in the bag wall 24 is disposed adjacent to the cooling band 32 to allow heat to be transferred from the battery cell 12 located in the cell bag 22 to the cooling band 32, as described in more detail below. The present disclosure contemplates other methods for placing or positioning the cooling band 32 in the battery holder 14, for example, the cooling band 32 can pass through a slot in the battery holder 14.

[0034] Additional references Figure 3 , which is shown in accordance with the present disclosure in such Figure 2 A cross-sectional view through the battery cell assembly 10 at the position shown. The cooling band 32 has a plurality of cooling channels 34. A heat exchange fluid or coolant (such as ethylene glycol, diethylene glycol, propylene glycol, polyalkylene glycol or a similar fluid) circulates through each of the plurality of cooling channels 34 disposed in the bag wall 24 of each of the plurality of cell bags 22. The coolant circulating through the cooling channels 34 receives heat generated by the battery cells 12 and transfers it to a location outside the battery cell assembly 10, thereby cooling the battery cells 12. In addition, there is a thermal interface material 36 disposed in an opening or window 33 in the wall 24 between each cooling band 32 and the outer shell surface 18 of the cell shell 16 of the battery cell 12 to further facilitate heat transfer from the battery cell 12 to the coolant in the plurality of cooling channels 34. The present disclosure contemplates the use of commercially available thermal interface materials cut or formed in the form of sheets or layers, for example, thermal interface materials manufactured by 3M TM A thermally conductive acrylic interface pad is provided. In the present disclosure, the thermal interface material 36 contacts the housing surface 18 of the cell housing 16 of the battery cell 12 and the surface of the cooling strip 32. The cooling strip 32 may be connected to a heat exchanger (not shown) that dissipates the heat absorbed by the coolant in the cooling channel 34.

[0035] like Figure 3 As shown, the cell housing 16 of the battery cell 12 has a housing surface 18. The housing surface 18 has a plurality of grooves 20 formed therein, such as in Figure 3A and Figure 3BThe cell housing 16 of the battery cell 12 also includes a first end 38 and a second end 40. A first plurality of grooves 42 of the plurality of grooves 20 are formed in the cell housing surface 18 at the first end 38 of the cell housing 16, and a second plurality of grooves 44 of the plurality of grooves 20 are formed in the cell housing surface 18 at the second end 40 of the cell housing 16.

[0036] In addition, the unit housing 16 further includes a first wall portion 48. The first wall portion 48 has a first wall thickness "t1". A second plurality of grooves 44 are formed in the first wall portion 48, such as Figure 3B , as shown in an expanded or enlarged view. In addition, the unit shell 16 includes a second wall portion 50. The second wall portion 50 has a second wall thickness "t2". The second wall thickness t2 is less than the first wall thickness t1 of the first wall portion 48. The second wall portion 50 is shown as being located at the second end 40 of the unit shell 16, however, the present disclosure contemplates that the second wall portion 50 may be disposed at one of the first end 38 and the second end 40 of the unit shell 16. The second wall thickness t2 is configured to allow the end or bottom 66 of the unit shell 16 to be separated from the rest of the unit shell to allow the release of gas accumulated in the unit shell.

[0037] Continue to refer Figure 3 The wall 24 of each of the plurality of cell pockets 22 of the battery holder 14 has a first end 52 and a second end 54. The wall surface 26 of the wall 24 has a second plurality of grooves 30 that interact with the first plurality of grooves 20 on the outer surface 18 of the cell shell 16. More specifically, the second plurality of grooves 30 includes a first group of grooves 56, such as Figure 3A As shown in the expanded view or enlarged view of FIG. 1 , a first set of grooves 56 are formed on the surface 26 of the wall 24 at the first end 38 of each unit bag in the plurality of unit bags 22; and a second set of grooves 58 are formed on the surface 26 of the wall 24 at the second end 40 of each unit bag in the plurality of unit bags 22, as shown in FIG. Figure 3B 1. The first plurality of grooves 20 on the cell housing 16 interact with the second plurality of grooves 30 on the wall 24 of each of the plurality of battery pouches 22 to collectively prevent the battery cell 12 from moving relative to the battery cell holder 14. The present disclosure contemplates adjusting the number of grooves 20, 30 to provide sufficient retention force to retain the battery cell 12 within the cell pouch 22 of the battery holder 14. For example, the number of grooves in the battery housing 16 and the wall 24 of the battery cell holder 14 may be increased to increase the retention force of the battery cell 12 in the battery cell holder 14.

[0038] The wall 24 also includes a plurality of protrusions 68 extending from one of the first end 52 and the second end 54 of the battery cell holder 14. For example, the plurality of protrusions 68 at the end 54 of the cell housing 16 define a vent channel 70. During a temperature rise of the battery cell 12, also known as a thermal runaway propagation (TRP) event, the gas accumulated in the battery housing may be released into the vent channel 40 by separating the cell housing 16 at the reduced wall thickness t2 of the wall portion 50 of the wall 24.

[0039] The present disclosure also contemplates a battery cell 12 assembly process. The process includes a first step of a blanking operation. The second step of the process includes a deep drawing operation to extend the cylindrical battery shell 16. The third step includes extending the cylindrical battery shell 16 to an appropriate length. The fourth step includes performing a grooving operation on the extended cylindrical battery shell, for example, to form a groove in the shell at the end of the shell. The fifth step of the process is to insert the core pack with the anode collector and the cathode collector into the shell. The sixth step involves filling the shell with electrolyte. The seventh and final step of the process is to crimp one end to the shell to form a sealed battery shell or battery shell 16.

[0040] Compared with the current design, the present invention has many advantages and benefits. For example, compared with the previous design, the interaction of the multiple grooves 20 in the battery cell 12 and the multiple grooves 30 in the battery cell holder 14 minimizes the movement of the battery cell on the vertical axis. In addition, the multiple grooves 20, 30 are also used to center the battery cell 12 in the cell bag 22 of the battery cell holder 14. In addition, the minimized vertical axis movement of the battery cell 12 in the cell bag 22 also minimizes the bending of the battery cell connector or metal contact. In addition, compared with the current design, the battery cell 12 can be assembled into the battery cell holder 14 more easily and accurately. For example, a series of suction cups attached to a rotating arm (which is then attached to one or more robot arms) can be used to place a group or multiple battery cells 12 in the battery cell holder at the same time. For example, the rotating arm can rotate in multiple directions (i.e., roll, yaw and pitch) to provide an effective assembly of the battery cells 12 in the battery cell holder 14.

[0041] This description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in a variety of forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent after studying the drawings, description and appended claims.

Claims

1. A battery cell assembly, comprising: a battery cell having a cell housing, wherein the cell housing has a housing surface, and wherein the housing surface has a first plurality of grooves formed therein; a battery cell holder having a plurality of cell pockets, wherein each of the cell pockets has a wall, and wherein the wall has a wall surface, wherein the wall surface has a second plurality of grooves that interact with a first plurality of grooves on an outer surface of the cell housing; and The first plurality of grooves on the cell housing interact with the second plurality of grooves on the wall of each of the plurality of cell pockets to jointly prevent the battery cell from moving relative to the battery cell seat.

2. The battery cell assembly according to claim 1, further comprising a plurality of cooling channels, wherein: Each of the plurality of cooling channels is disposed in a wall of each of the plurality of cell pockets.

3. The battery cell assembly according to claim 2 further includes a thermal interface material disposed between each of the plurality of cooling channels and an outer surface of a cell shell of the battery cell to promote heat transfer from the battery cell to the plurality of cooling channels.

4. The battery cell assembly according to claim 1, wherein: The cell shell of the battery cell also includes a first end and a second end, wherein a first plurality of the first plurality of grooves are formed in the cell shell surface at the first end of the cell shell, and a second plurality of the first plurality of grooves are formed in the cell shell surface at the second end of the cell shell.

5. The battery cell assembly according to claim 4, wherein: The unit housing further includes a first wall portion, wherein the first wall portion has a first wall thickness, and wherein the first plurality of grooves are formed in the first wall portion.

6. The battery cell assembly according to claim 5, wherein: The unit housing further includes a second wall portion, wherein the second wall portion has a second wall thickness, and wherein the second wall thickness is smaller than a first wall thickness of the first wall portion.

7. The battery cell assembly according to claim 6, wherein: The second wall thickness of the second wall portion is provided at one of the first end and the second end of the unit housing.

8. The battery cell assembly according to claim 6, wherein: The wall of each of the plurality of unit bags has a first end and a second end, wherein a first plurality of the second plurality of grooves are formed on the wall surface at the first end of each of the plurality of unit bags, and a second plurality of the second plurality of grooves are formed on the wall surface at the second end of each of the plurality of unit bags.

9. The battery cell assembly according to claim 1, wherein: The battery cell holder further includes a protrusion extending from one of the first end and the second end of the battery cell holder, and wherein the protrusion and the end of the shell define a vent passage.

10. A battery cell assembly comprising: a battery cell having a cell housing, wherein the cell housing has a housing surface, and wherein the housing surface has a first plurality of grooves formed therein; A battery cell holder having a plurality of cell pockets, wherein each of the cell pockets has a wall, and wherein the wall has a wall surface, wherein the wall surface has a second plurality of grooves that interact with a first plurality of grooves on an outer surface of the cell housing; and wherein the first plurality of grooves on the cell housing interact with the second plurality of grooves on the wall of each of the plurality of cell pockets to jointly prevent the battery cell from moving relative to the battery cell holder; and A plurality of cooling channels, wherein each channel of the plurality of cooling channels is disposed at a wall of each unit bag of the plurality of unit bags.

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