Battery pack and device including the same

Abstract

A battery pack according to an embodiment of the present invention comprises: one or more first battery modules, each first battery module comprising a plurality of battery cells; and one or more second battery modules, each second battery module including a plurality of battery cells disposed adjacent to a respective first battery module, where the first battery module and the second battery module have different maximum states of charge (SOC).

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0144751 filed in the Korean Intellectual Property Office on November 2, 2022, the entire contents of which are incorporated herein by reference.

[0003] The present disclosure relates to a battery pack and a device including the same, and more particularly, to a battery pack having improved safety and a device including the same. Background Art

[0004] In modern society, as the use of portable devices such as mobile phones, laptop computers, video cameras, digital cameras, etc. has become widespread, the development of technology in the field related to the above-mentioned mobile devices has become more active. In addition, rechargeable secondary batteries are used as power sources for electric vehicles (EV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (P-HEV), etc. to solve air pollution such as existing gasoline vehicles using fossil fuels, so the demand for the development of secondary batteries is increasing.

[0005] Currently commercial secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, lithium secondary batteries, etc. Among them, lithium secondary batteries rarely have a memory effect compared to nickel-based secondary batteries, so lithium secondary batteries have attracted attention due to the advantages of free charge and discharge, very low self-discharge rate and high energy density.

[0006] These lithium secondary batteries mainly use lithium-based oxides and carbon materials as positive electrode active materials and negative electrode active materials, respectively. A lithium secondary battery includes: an electrode assembly, in which a positive electrode plate and a negative electrode plate coated with positive electrode active materials and negative electrode active materials, respectively, are arranged with a separator sandwiched therebetween; and an external material, i.e., a battery case, which seals and contains the electrode assembly and the electrolyte.

[0007] Generally, lithium secondary batteries may be divided into a can type secondary battery in which an electrode assembly is built into a metal can and a pouch type secondary battery in which an electrode assembly is built into a pouch of an aluminum laminate, according to the shape of an exterior material.

[0008] In the case of a secondary battery for a small device, 2 or 3 battery cells are provided, but in the case of a secondary battery for a medium or large device such as an automobile, a battery module in which a plurality of battery cells are electrically connected is used. These battery modules have improved capacity and output by connecting a plurality of battery cells in series or in parallel and forming a battery assembly. In addition, one or more battery modules may be installed with various control and protection systems such as a battery management system (BMS) and a cooling system to form a battery pack.

[0009] When a battery pack is configured by connecting a plurality of battery cells in series / parallel, it is generally a method of configuring the battery pack by first configuring a battery module including at least one battery cell and adding other components using the at least one battery module. The number of battery modules included in the battery pack or the number of battery cells included in the battery module can be set in various ways according to the required output voltage or charge / discharge capacity.

[0010] In particular, recently, due to the development of high-capacity cells, the safety of secondary batteries, especially the heat transfer characteristics, has been considered important. As the cell capacity increases, the heat transfer safety decreases, and thus it is required to improve the heat transfer safety. Summary of the invention

[0011] Technical issues

[0012] The present disclosure seeks to provide a battery pack having enhanced safety while using existing high-capacity battery cells and a device including the battery pack.

[0013] However, the problems to be solved by the embodiments of the present disclosure are not limited to the above-mentioned problems and can be expanded in various ways within the scope of the technical concept included in the present disclosure.

[0014] Technical Solution

[0015] A battery pack according to an embodiment of the present disclosure includes: one or more first battery modules, the one or more first battery modules including a plurality of battery cells; and one or more second battery modules, the one or more second battery modules being respectively arranged adjacent to the first battery modules and including a plurality of battery cells, wherein the first battery module and the second battery module are different from each other in terms of maximum state of charge (SOC).

[0016] A maximum SOC of the one or more first battery modules may be 100%, and a maximum SOC of the one or more second battery modules may be 90%.

[0017] The battery pack may further include a control unit connected to each of the one or more first battery modules and the one or more second battery modules to perform charging and SOC control.

[0018] When charging is performed, the control unit may be configured to control the SOC of the one or more first battery modules to be 100%, and control the SOC of the one or more second battery modules to be 90%.

[0019] Any one of the one or more first battery modules may be disposed to be surrounded by the one or more second battery modules.

[0020] Any one of the one or more second battery modules may be disposed to be surrounded by the one or more first battery modules.

[0021] The one or more first battery modules and the one or more second battery modules may be alternately arranged.

[0022] The battery cells included in the first battery module and the battery cells included in the second battery module may be of the same type.

[0023] The battery pack may further include a pack frame enclosing the one or more first battery modules and the one or more second battery modules.

[0024] A device according to another embodiment of the present disclosure may include at least one battery pack.

[0025] Beneficial Effects

[0026] According to an embodiment of the present disclosure, a battery pack having enhanced safety while using an existing high-capacity battery cell and a device including the battery pack may be provided.

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

[0028] Figure 1 is an exploded perspective view of a battery module included in a battery pack according to an embodiment of the present disclosure.

[0029] Figure 2 is a diagram showing a battery pack according to an embodiment of the present disclosure.

[0030] Figure 3 The schematic diagram shows a control unit and a charging unit. Figure 2 Diagram of a battery pack. DETAILED DESCRIPTION

[0031] The present disclosure is described more fully below in conjunction with the accompanying drawings so that those skilled in the art can easily implement the embodiments of the present disclosure. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein.

[0032] In order to clearly describe the present disclosure, parts irrelevant to the description are omitted, and the same reference numerals are denoted by the same or similar parts throughout the specification.

[0033] In addition, since the size and thickness of each component shown in the drawings are arbitrarily shown for the convenience of explanation, the present disclosure is not necessarily limited to those shown. In the drawings, the thickness is enlarged to clearly show each layer and region. In addition, in the drawings, the thickness of some layers and regions is exaggerated for the convenience of explanation.

[0034] In addition, it should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements. In addition, "above" or "on" a reference portion means above or below the reference portion, and does not necessarily mean "above" or "on" in the opposite direction of gravity.

[0035] Furthermore, throughout the specification, when a part “includes” a certain component, it means that unless otherwise specified, the part may also include other components without excluding the other components.

[0036] Furthermore, throughout the specification, when it is referred to as “on a plane”, it means when the target portion is viewed from above, and when it is referred to as “on a cross section”, it means when a cross section of the target portion cut vertically is viewed from the side.

[0037] In the following, reference is made to Figures 1 to 3 A battery pack of the present disclosure is described.

[0038] Figure 1 is an exploded perspective view of a battery module included in a battery pack according to an embodiment of the present disclosure. Figure 2 is a diagram showing a battery pack according to an embodiment of the present disclosure. Figure 3 The schematic diagram shows a control unit and a charging unit. Figure 2 Diagram of a battery pack.

[0039] refer to Figure 1 Each of the first battery module 100 and the second battery module 200 included in the battery pack according to an embodiment of the present disclosure includes: a battery cell assembly 400 including one or more battery cells; a module frame 210 accommodating the battery cell assembly 400; and an end plate 300, which is located at both ends of the battery cell assembly 400 in the longitudinal direction and is connected to the opening of the module frame 210.

[0040] The battery cell assembly 400 is an assembly of a secondary battery including a plurality of battery cells 112. The battery cell assembly 400 may include a plurality of battery cells 112, and each battery cell includes an electrode lead 114. The battery cell 112 may be a pouch-type battery cell having a plate shape, but is not limited thereto. The electrode lead 114 is a positive lead or a negative lead, and the end of the electrode lead 114 of each battery cell 112 may be bent in one direction, and thus may contact the end of the electrode lead 114 of another adjacent battery cell 112. The two electrode leads 114 in contact with each other may be fixed to each other by welding or the like, and thereby, an electrical connection may be made between the battery cells 112 inside the battery cell assembly 400.

[0041] In addition, the bus bar frame 500 accommodated in the module frame 210 may be provided together with the battery cell assembly 400. The bus bar frame 500 may include an upper frame 510 located at the top of the battery cell assembly 400, a front frame 520 located at the front of the battery cell assembly 400, and a rear frame 530 located at the rear of the battery cell assembly 400, and bus bars 540 connected to the electrode leads 114 of the battery cells 112 constituting the battery cell assembly 400 may be mounted on the front frame 520 and the rear frame 530.

[0042] A plurality of battery cells 112 are stacked vertically so that the electrode leads 114 are aligned in one direction to form a battery cell assembly 400. The battery cell assembly 400 is accommodated in a module frame 210 having at least one opening opened in the longitudinal direction of the battery cell assembly 400. At this time, the electrode lead 114 may be pulled to the outside of the module frame 210 through the opening, and the pulled electrode lead 114 may be respectively coupled to the front frame 520 and the rear frame 530 of the bus bar frame 500 and electrically connected to the bus bar 540 installed therein. Here, the bus bar frame 500 may be made of an insulating material, for example, a non-conductive synthetic resin, and the bus bar 540 may be made of a conductive metal material.

[0043] Each of the first battery module 100 and the second battery module 200 may include a flexible printed circuit board (FPCB) (not shown) extending in the longitudinal direction of the module frame 210 and mounted on the top of the battery cell assembly 400, and configured to sense the battery cell 112. In addition, the first battery module 100 and the second battery module 200 may include various electrical components, such as an internal circuit board (ICB) and a battery management system (BMS). Electrical components such as the ICB and the BMS may be electrically connected to the plurality of battery cells 112.

[0044] Each of the first battery module 100 and the second battery module 200 may further include a thermally conductive resin layer 700 between the lower surface of the battery cell assembly 400 and the module frame 210. The thermally conductive resin layer 700 is formed by injecting a thermally conductive resin, and may be used to transfer heat generated from the battery cell assembly 400 to the bottom of the first battery module 100 and the second battery module 200, and fix the battery cell assembly 400 within the first battery module 100 and the second battery module 200.

[0045] Meanwhile, the heat sink 800 may be disposed on the side surface of the battery cell assembly 400 and accommodated together in the module frame 210 , but is not limited thereto.

[0046] The configurations of the first battery module 100 and the second battery module 200 have been described above, but the shapes or configurations thereof are not limited thereto and may be different in some cases.

[0047] Next, we will refer to Figure 2 and Figure 3 A battery pack 10 according to an embodiment of the present disclosure is described.

[0048] The battery pack 10 includes one or more first battery modules 100 , one or more second battery modules 200 , and a pack frame 11 accommodating the one or more first battery modules 100 and the one or more second battery modules 200 .

[0049] The first battery module 100 and the second battery module 200 are different from each other in terms of maximum state of charge (SOC). Here, SOC is the ratio of the remaining capacity to the maximum capacity and is generally expressed in a range of 0 to 100%. The remaining capacity represents the amount of charge currently stored in the battery pack 10. In the present embodiment, the first battery module 100 and the second battery module 200 control the maximum SOC differently when controlling the SOC. Preferably, the maximum SOC of the first battery module 100 is 100%, and the maximum SOC of the second battery module 200 is 90%.

[0050] The first battery modules 100 and the second battery modules 200 which are different in maximum SOC may be alternately arranged, such as Figure 2 That is, the second battery module 200 may be arranged in all directions with respect to one first battery module 100 , and the first battery module 100 may be arranged in all directions with respect to one second battery module 200 .

[0051] In the case where the battery pack 10 includes the first battery module 100 and the second battery module 200 arranged as described above, the second battery module 200 exhibits a lower explosion pressure when the battery cell catches fire, thereby improving the safety of heat propagation. That is, in the case of the second battery module 200 with an SOC of 90%, the explosion pressure (pressure applied when the battery cell catches fire) is about 40% lower than the explosion pressure of the first battery module 100 with an SOC of 100%. Therefore, when the fire time and the explosion pressure are measured by applying heat to the second battery module 200 and the first battery module 100 arranged alternately when a fire breaks out, the fire time increases and the explosion pressure decreases compared to the case where only a module with a 100% SOC is set and all the fires are caught at once. In addition, even if a fire occurs in the first battery module 100, the explosion pressure may be lower due to the lower SOC of the adjacent second battery module 200, and when a fire occurs in the second battery module 200, the impact on the adjacent first battery module 100 can be reduced because the explosion pressure itself is lower.

[0052] On the other hand, when the maximum SOC of the second battery module 200 is above 90%, it is difficult to obtain the above-mentioned effect of reducing the explosion pressure. When the maximum SOC is less than 90%, the high output required by the device cannot be achieved. Therefore, the maximum SOC can be controlled to 90%.

[0053] In addition, in the case of the first battery module 100 and the second battery module 200, the above-mentioned effect can be obtained by only changing the SOC in the configuration of the battery modules including the same type of battery cells 112 so as to adjust the output without changing the type or structure of the battery cells 112 included in each battery module.

[0054] In order to control the SOC, the battery pack 10 of the present embodiment may include a control unit 610 connected to the plurality of first battery modules 100 and the plurality of second battery modules 200. The control unit 610 may also be connected to a charging unit 620 to control the charging unit 620 to limit the maximum SOC of the first battery module 100 and the second battery module 200 to 100% and 90%, respectively, while monitoring the SOC when charging the first battery module 100 and the second battery module 200. Such monitoring and control may be achieved by estimating and controlling the SOC according to one or a combination of two or more of various known techniques.

[0055] As described above, according to the battery pack 10 of the embodiment of the present disclosure, a plurality of battery modules having different maximum SOCs are alternately arranged with each other, thereby improving heat propagation characteristics (ie, extending the ignition time and reducing the explosion pressure) when battery cells included in the battery modules catch fire.

[0056] The battery pack described above can be applied to various devices. These devices can be applied to vehicles such as electric bicycles, electric vehicles, hybrid vehicles, etc., but the present disclosure is not limited thereto, and can be applied to various devices that can use battery modules and battery packs including battery modules, which also fall within the scope of the present disclosure.

[0057] Although the embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto, and various modifications and improvements made by a person of ordinary skill in the art to which the present disclosure belongs also belong to the scope of the present disclosure.

[0058] [Explanation of Reference Numerals]

[0059] 100: First battery module

[0060] 200: Second battery module

[0061] 10: Battery Pack

[0062] 11: Battery Pack Frame

[0063] 112: Battery cells

[0064] 610: Control unit

[0065] 620: Charging unit

Claims

1. A battery pack, comprising: one or more first battery modules, the one or more first battery modules comprising a plurality of battery cells; as well as one or more second battery modules, each of which is disposed adjacent to the first battery module and includes a plurality of battery cells, The first battery module and the second battery module are different from each other in terms of maximum state of charge (SOC).

2. The battery pack according to claim 1, wherein: A maximum SOC of the one or more first battery modules is 100%, and a maximum SOC of the one or more second battery modules is 90%.

3. The battery pack according to claim 1, further comprising: A control unit is connected to each of the one or more first battery modules and the one or more second battery modules to perform charging and SOC control.

4. The battery pack according to claim 3, wherein: When charging is performed, the control unit is configured to control the SOC of the one or more first battery modules to 100%, and control the SOC of the one or more second battery modules to 90%.

5. The battery pack according to claim 1, wherein: Any one of the one or more first battery modules is disposed to be surrounded by the one or more second battery modules.

6. The battery pack according to claim 1, wherein: Any one of the one or more second battery modules is disposed to be surrounded by the one or more first battery modules.

7. The battery pack according to claim 1, wherein: The one or more first battery modules and the one or more second battery modules are alternately arranged.

8. The battery pack according to claim 1, wherein: The battery cells included in the first battery module and the battery cells included in the second battery module are of the same type.

9. The battery pack according to claim 1, further comprising: A battery pack frame encapsulates the one or more first battery modules and the one or more second battery modules.

10. A device comprising at least one battery pack according to claim 1.

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