Battery module and battery pack including same

Abstract

A battery module according to an embodiment of the present disclosure comprises: a battery cell stack in which a plurality of battery cells are stacked; a module case configured to accommodate the stack of battery cells; a film heater provided between the module case and an outermost battery cell of the battery cell stack; and a dummy battery cell disposed between the film heater and the outermost battery cell.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0180416 filed in the Korean Intellectual Property Office on December 21, 2022, the entire contents of which are incorporated herein by reference.

[0003] The present disclosure relates to a battery module and a battery pack including the same, and more particularly, to a battery module in which environmental deviation between battery cells is reduced and a battery pack including the same. Background Art

[0004] Secondary batteries have attracted much attention as energy sources for various products such as mobile devices and electric vehicles. Such secondary batteries are considered to be valuable energy sources that can replace fossil fuels used in products in related technologies. Since secondary battery products do not produce byproducts when using energy, secondary batteries have attracted attention as environmentally friendly energy sources.

[0005] Recently, secondary batteries are required to be used as energy storage sources and secondary battery structures having high capacity are required, and thus, there is an increasing demand for battery packs having a multi-module structure in which a plurality of battery modules are assembled and each has a plurality of secondary batteries connected in series and / or parallel.

[0006] Meanwhile, generally, in order to manufacture a battery pack by connecting a plurality of battery cells in series / parallel, a battery module having at least one battery cell is first manufactured, and then the battery pack is manufactured by using the at least one battery module and adding other constituent elements.

[0007] The battery module includes a battery cell stack made by stacking a plurality of battery cells, a module case configured to accommodate the battery cell stack, and a compression pad disposed between the module case and an outermost battery cell of the battery cell stack or between a plurality of battery cells.

[0008] Figure 1 is a diagram showing a battery module in the related art. Figure 2 It is shown Figure 1 Figure 2 is a diagram of a cross section of a battery module.

[0009] In the battery module 1 in the related art, the outermost battery cells of the battery cell stack made by stacking a plurality of battery cells 11 are arranged in direct contact with the module case 20. In this case, when the number of battery cells 11 constituting the battery module 1 increases, performance deviation occurs in the respective battery cells 11 provided in the battery module 1, and the performance deviation eventually inevitably affects the performance of a battery pack made by connecting the battery modules in series or in parallel.

[0010] Since the battery cell 11 is a heat generating element, the temperature of the battery cell 11 rises when performing tests related to output, fast charging, life, etc. However, since one surface of the battery cell located on the outermost side of the battery module 1 contacts the module housing 20 of the battery module instead of the battery cell, the temperature effect affecting the performance of the battery cell is lower than the temperature effect of the battery cell located in the middle of the battery module. As a result, the performance of the battery module 1 may depend on the outermost battery cell. Therefore, the performance of the battery module may generally deteriorate. Summary of the invention

[0011] Technical issues

[0012] The present disclosure seeks to provide a battery module capable of minimizing performance deviation and temperature deviation between battery cells caused by positions in the battery module, and a battery pack including the battery module.

[0013] The technical problems of the present disclosure are not limited to the aforementioned technical problems, and other technical problems not mentioned above can be clearly understood by those skilled in the art from the following description.

[0014] Technical Solution

[0015] In order to achieve the above-mentioned purpose, a battery module according to an embodiment of the present disclosure includes: a battery cell stack, in which a plurality of battery cells are stacked; a module housing, which is configured to accommodate the battery cell stack; a film heater, which is arranged between the module housing and the outermost battery cell of the battery cell stack; and a dummy battery cell, which is arranged between the film heater and the outermost battery cell.

[0016] The dummy battery cell may have the same configuration as the plurality of battery cells, and may not be electrically connected to the plurality of battery cells.

[0017] The dummy battery cells may not be charged or discharged.

[0018] The battery module may further include: a first temperature sensor attached to the dummy battery cell.

[0019] The battery module may further include: a second temperature sensor attached to a battery cell disposed at an innermost side among the plurality of battery cells.

[0020] The battery module may further include: a controller configured to control a first temperature measured by the first temperature sensor and a second temperature measured by the second temperature sensor so that the first temperature is maintained equal to the second temperature.

[0021] The controller may be connected to the film heater and heat the film heater based on the monitoring results of the first temperature and the second temperature.

[0022] The pressures applied to the respective plurality of battery cells may be equal to each other.

[0023] The film heater may be configured as at least one of a carbon element, a copper foil bus bar, a silver bus bar, a base PET film, and a Laminex film as a heating element.

[0024] According to another embodiment of the present disclosure, a battery pack may include at least one of the above-mentioned battery modules.

[0025] Beneficial Effects

[0026] According to the battery module of the embodiments of the present disclosure and the battery pack including the battery module, a dummy battery cell that is not charged or discharged can be disposed at the position of the outermost battery cell with a relatively low temperature among the battery cells, a membrane heater can be disposed on the dummy battery cell, and a temperature sensor can be used to maintain the temperature between the dummy battery cell and the middle battery cells consistent, so that the temperature and pressure of the battery cells can be maintained consistent, and the deviation in performance and life between the battery cells can be minimized.

[0027] The effects of the present disclosure are not limited to the aforementioned effects, and other effects not mentioned above will be clearly understood by those skilled in the art from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a diagram showing a battery module in the related art.

[0029] Figure 2 It is shown Figure 1 Figure 2 is a diagram of a cross section of a battery module.

[0030] Figure 3 is a diagram illustrating a battery module according to an embodiment of the present disclosure.

[0031] Figure 4 It shows dismantled Figure 3 Diagram of the status of the battery module.

[0032] Figure 5 It is shown along Figure 3 A diagram of a cross section taken along line AA' in FIG.

[0033] Figure 6 is a conceptual diagram illustrating a configuration in which a battery module is connected to a controller according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0034] Hereinafter, several exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the exemplary embodiments. The present disclosure can be implemented in various different ways and is not limited to the embodiments described herein.

[0035] In order to clearly describe the present disclosure, parts irrelevant to the description will be omitted, and the same or similar constituent elements will be denoted by the same reference numerals throughout the specification.

[0036] In addition, the size and thickness of each constituent element shown in the drawings are arbitrarily shown for the convenience of description, but the present disclosure is not limited thereto. In order to clearly describe several layers and regions, their thicknesses are magnified in the drawings. In the drawings, the thicknesses of some layers and regions are magnified for the convenience of description.

[0037] In addition, when a component such as a layer, film, region, or plate is described as being “above” or “on” another component, the component may be “directly” “on” the other component, and the component may also be on the other component with other components interposed therebetween. Conversely, when a component is described as being “directly” “above” another component, there are no components therebetween. In addition, when a component is described as being “above” or “on” a reference portion, the component may be “above” or “below” the reference portion, and such a configuration does not necessarily mean that the component is “above” or “on” the reference portion in a direction opposite to gravity.

[0038] Throughout the specification, unless explicitly described to the contrary, the word “comprises / comprising” and variations thereof will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0039] In the following, reference will be made to Figures 3 to 6 A battery module according to an embodiment of the present disclosure is described.

[0040] Figure 3 is a diagram showing a battery module according to an embodiment of the present disclosure, Figure 4 It shows dismantled Figure 3 A diagram of the status of the battery modules in Figure 5 It is shown along Figure 3 A diagram of a cross section taken along line AA' in FIG. Figure 6 is a conceptual diagram illustrating a configuration in which a battery module is connected to a controller according to an embodiment of the present disclosure.

[0041] Reference Figures 3 to 6A battery module 10 according to an embodiment of the present disclosure includes a battery cell stack 100 made by stacking battery cells 110, a module housing 200 configured to accommodate the battery cell stack 100, a dummy battery cell 111 disposed between the module housing 200 and the outermost battery cell, and a film heater 300 disposed between the module housing 200 and the dummy battery cell 111.

[0042] The battery cell 110 may be a secondary battery and configured as a soft-pack secondary battery. The battery cell 110 may be provided as a plurality of battery cells 110, and the plurality of battery cells 110 are stacked on each other and electrically connected to each other, thereby constituting a battery cell stack. The plurality of battery cells may each include an electrode assembly, a housing configured to accommodate the electrode assembly, and an electrode lead protruding from the electrode assembly. The electrode assembly may include a positive plate, a negative plate, a separator, and the like. The housing may be configured as a laminate, which is configured to accommodate the electrode assembly and is made of a resin layer and a metal layer. The electrode lead may protrude from the housing and be electrically connected to the electrode assembly. The electrode lead may be provided at two opposite ends of the battery cell 110. According to an embodiment of the present disclosure, the battery cell has a structure in which two electrode leads are opposite to each other and protrude from two opposite ends of the battery cell 110.

[0043] According to an embodiment of the present disclosure, the module housing 200 may have an upper surface, a lower surface, a left surface, and a right surface to accommodate the battery cell stack 100. However, the module housing 200 may include a U-shaped module housing and an upper plate configured to cover the open upper side of the U-shaped module housing. Alternatively, the module housing 200 may include an inverted U-shaped module housing and a lower plate configured to cover the lower side of the module housing. The module housing 200 may protect the battery cell 110 and components connected to the battery cell 110 from external physical impacts.

[0044] The dummy battery cell 111 is disposed between the module housing 200 and the outermost battery cell 110 of the battery cell stack 100. The dummy battery cell 111 is a battery cell configured to be the same as the battery cell 110. The dummy battery cell 111 is disposed at two opposite ends of the battery cell stack 100. The dummy battery cell 111 is not electrically connected, so that the dummy battery cell 111 will not be charged or discharged. The dummy battery cell 111 can be used to absorb the pressure generated when the battery cell 110 expands. In addition, the battery cell is disposed at the outermost side and therefore has a larger temperature deviation and pressure deviation relative to the battery cell disposed in the middle, and the overall performance of the battery module 10 in the prior art is degraded due to the degradation of performance, and the battery cell is set to a dummy battery cell 111 that will not be charged or discharged. Therefore, even if the temperature deviation and pressure deviation between the dummy battery cells 111 increase, the increase in temperature deviation and pressure deviation will not affect the overall performance of the battery module 10. In addition, since all battery cells 110 that are electrically connected and charged and discharged are adjacent to each other or adjacent to the dummy battery cell 111, the battery cells 110 can withstand the same pressure. That is, in the prior art, since one surface of the battery cell 110 located on the outermost side is adjacent to other components (module housing 200, etc.) and is placed in an environment different from other battery cells 110 arranged on the inner side, a pressure difference is generated between these battery cells. In contrast, in the case of the present embodiment, the dummy battery cell 111 is arranged as described above, and all battery cells 110 can withstand the same pressure.

[0045] The film heater 300 is disposed between the module housing 200 and the dummy battery cell 111 of the battery cell stack 100. Therefore, the film heater 300 can increase the temperature of the dummy battery cell 111 adjacent to the film heater 300. The film heater 300 can be configured as a carbon element, a copper foil bus bar, a silver bus bar, a base PET film, and an adhesive film as a heating element. The film having the above structure can sometimes be used to improve heating efficiency.

[0046] In addition, if Figure 5 As shown, in order to minimize the performance deviation between the battery cells 110 according to the positions of the battery cells 110 in the battery module 10, the first temperature sensor 410 is installed on the dummy battery cell 111, and the second temperature sensor 420 is installed on the battery cell 110 located in the middle portion. The temperature of the battery cell 110 and the temperature of the dummy battery cell 111 are monitored by the first temperature sensor and the second temperature sensor, which can minimize the temperature deviation between the battery cells of the battery cell stack 100. That is, as Figure 6As shown, the first temperature sensor 410 and the second temperature sensor 420 may be connected to the controller 500, and the controller 500 may acquire the first temperature measured by the first temperature sensor 410 and the second temperature measured by the second temperature sensor 420. When the controller 500 determines that the temperature of the dummy battery cell 111 is lower based on the measured temperatures, the controller 500 may perform control to heat the film heater 300, thereby eliminating the temperature deviation between the battery cell 110 and the dummy battery cell 111.

[0047] In the case where the temperature of the dummy battery cell 111 disposed on the outside and the temperature of the battery cell 110 located in the middle portion are monitored and controlled to be equal to each other, the temperature of the battery cell 110 disposed between the dummy battery cell 111 and the battery cell 110 located in the middle portion can also be kept consistent. In addition, since the dummy battery cell 111 absorbs the pressure applied to the battery cell 110, the pressure applied to the battery cell 110 other than the dummy battery cell 111 can be kept consistent regardless of the position of the battery cell 11 in the battery module 10. As described above, since the temperature and pressure can be kept consistent regardless of the position of the battery cell 11 in the battery module 10, the battery cell characteristics and degradation rate of the battery cell 110 can be kept consistent. Therefore, the deviation between the characteristics and degradation rates between the battery cells 110 is reduced, and problems in some of the battery cells 110 can be prevented, especially the situation where the battery cell 110 disposed on the outside reduces the overall performance of the battery module 10.

[0048] Meanwhile, the present embodiment has described the case where the film heater 300 corresponds to the entire area of ​​the dummy battery cell 111, but the present disclosure is not limited thereto. Within the range where the film heater 300 does not overlap with the electrode lead, the size of the film heater 300 can be reduced. In this case, the film heater 300 can be positioned close to the middle portion of the dummy battery cell 111. In addition, the present embodiment has described the case where the film heater 300 is only disposed on the dummy battery cell 111, but the present disclosure is not limited thereto. Even when the film heater 300 is disposed between the battery cells 110 disposed close to the inside, the film heater 300 can be controlled as needed to locally increase the temperature of the battery cell 110. In addition, as long as the position and size of the temperature sensors 410 and 420 are suitable for determining the temperature of the battery cell 110, the position and size of the temperature sensors 410 and 420 can also be appropriately adjusted without particular limitation.

[0049] The battery module 10 described above may be included in a battery pack. The battery pack may be a structure made by packaging one or more battery modules according to the present embodiment while adding a cooling device, a battery management system (BMS) that manages the temperature or voltage of the battery, and the like.

[0050] The battery pack can be applied to various devices. Examples of such devices may include transportation devices such as electric bicycles, electric vehicles, and hybrid vehicles, but the present disclosure is not limited thereto and may be applied to various devices that can use battery modules. These configurations may also fall within the scope of the present disclosure.

[0051] Although exemplary embodiments of the present disclosure have been shown and described above, the present disclosure is not limited to specific exemplary embodiments, and those skilled in the art to which the present disclosure belongs can certainly make various modifications without departing from the subject matter of the present disclosure required in the claims. In addition, these modifications should not be understood separately from the technical spirit or prospect of the present disclosure.

[0052] <Description of Reference Numerals>

[0053] 100: Battery cell stack

[0054] 110: Battery Cell

[0055] 111: Dummy battery cell

[0056] 200: Module housing

[0057] 300: Film heater

[0058] 410: First temperature sensor

[0059] 420: Second temperature sensor

Claims

1. A battery module, comprising: A battery cell stack, wherein a plurality of battery cells are stacked; a module housing configured to accommodate the battery cell stack; a film heater disposed between the module housing and an outermost battery cell of the battery cell stack; as well as A dummy battery cell is provided between the film heater and the outermost battery cell.

2. The battery module according to claim 1, wherein: The dummy battery cell has the same configuration as the plurality of battery cells and is not electrically connected to the plurality of battery cells.

3. The battery module according to claim 2, wherein: The dummy battery cell is not charged or discharged.

4. The battery module according to claim 1, further comprising: A first temperature sensor is attached to the dummy battery cell.

5. The battery module according to claim 4, further comprising: A second temperature sensor is attached to a battery cell disposed at an innermost side among the plurality of battery cells.

6. The battery module according to claim 5, further comprising: A controller is configured to control a first temperature measured by the first temperature sensor and a second temperature measured by the second temperature sensor so that the first temperature is kept equal to the second temperature.

7. The battery module according to claim 6, wherein: The controller is connected to the film heater, and heats the film heater based on monitoring results of the first temperature and the second temperature.

8. The battery module according to claim 1, wherein: The pressures applied to the respective plurality of battery cells are equal to each other.

9. The battery module according to claim 1, wherein: The film heater is configured as at least one of a carbon element, a copper foil bus bar, a silver bus bar, a base PET film, and an adhesive film as a heating element.

10. A battery pack comprising the battery module according to claim 1.

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