Battery module including a bent sensing unit and electronic device including the same

Abstract

The present invention relates to a battery module including a battery cell stack in which pouch-type battery cells are stacked, bus bars that connect to electrode leads of the pouch-type battery cells, a housing for fixing the bus bars, and a sensing unit that is disposed in the housing, wherein the sensing unit is attached to a first surface of the housing that faces the battery cell stack and a second surface that is the outer surface opposite to the first surface.

Description

[Technical field]

[0001] This application claims the benefit of priority to Korean Patent Application No. 2021-0074882 dated June 9, 2021, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery module including a sensing unit having a bent shape and an electronic device including the same, particularly to a battery module including a sensing unit having a bent shape attached to a front surface and a rear surface of a housing and an electronic device including the same. [Background technology]

[0003] Lithium secondary batteries, which can be used as an energy source with high energy density and high output, are applied not only to small products such as portable devices but also to medium and large products such as electric vehicles, hybrid electric vehicles, and power storage devices.

[0004] The lithium secondary battery is attracting attention as an environmentally friendly energy source since it can dramatically reduce the use of fossil fuels that have been used as a conventional energy source, and since it generates almost no by-products during use.

[0005] In order to apply the lithium secondary battery to medium and large-sized products, there is an increasing need for a large capacity and high output structure. Accordingly, a battery module is formed by connecting a plurality of lithium secondary batteries in parallel and / or series, and other components are added to one or more of the battery modules to form a battery pack.

[0006] The number of battery cells included in the battery module and the number of battery modules included in the battery pack may be set according to an output voltage and capacity required for a device to which the battery pack is attached.

[0007] When using an energy source including a lithium secondary battery, it is important to not only increase the capacity of the battery module but also to shorten the charging time in order to improve user convenience.

[0008] However, when performing fast charging, heat generation from the battery module has been pointed out as a problem, which is directly related to safety, and as a solution to this problem, a structure that increases the width of the electrode lead has been proposed as an alternative.

[0009] However, in conventional battery modules, a flexible printed circuit board (FPCB) for measuring the voltage, current, and temperature of the battery cells is attached to one side of the housing, so there is a limit to increasing the width of the electrode lead.

[0010] In this regard, FIG. 1 is a partial perspective view of a conventional battery module.

[0011] 1, an electrode lead 110 protrudes from one side of a battery cell stack in which a plurality of pouch-type battery cells 100 are closely arranged, and the electrode lead 110 is electrically connected to a bus bar 200. The bus bar 200 is attached and fixed to a housing 300, and an FPCB, which is a sensing unit 400 bent in the y and z directions, is attached to the outer surface of the housing 300.

[0012] In this way, the structure for securing the space for the sensing unit 400 arranged long along the y direction is L The length in the y direction, which is the size in the y direction, is less than 50% of the height H of the housing, making it difficult to increase the width of the electrode lead. As the width of the electrode lead becomes smaller, the rate of temperature increase increases, making it difficult to solve the problem of heat generation in the battery module that occurs during fast charging.

[0013] As a method for solving the heat generation of a battery module, Patent Document 1 proposes a structure in which a thermally conductive adhesive is uniformly applied over the entire upper side of a battery cell assembly, and discloses a battery module that allows cooling not only through the lower side but also through the upper side of the battery cell assembly.

[0014] Patent Document 1 presents a structure in which a thermally conductive adhesive is applied to improve the cooling performance of a battery module, but fails to disclose a structure that can increase the width of the electrode lead as an alternative to reduce heat generation during fast charging.

[0015] Therefore, there is a need for a battery module model having a structure that allows the width of the electrode leads to be increased so as to reduce heat generation, which is a problem during fast charging of the battery module. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] Korean Patent No. 10-2150679 Summary of the Invention [Problem to be solved by the invention]

[0017] The present invention has been made to solve the above problems, and aims to provide a battery module including a sensing unit having a bent shape so that heat generation of a battery cell can be reduced by using electrode leads having a wide width, and an electronic device including the same. [Means for solving the problem]

[0018] To achieve this object, a battery module according to the present invention includes a battery cell stack in which pouch-type battery cells are stacked, a bus bar that is coupled to an electrode lead of the pouch-type battery cell, a housing for fixing the bus bar, and a sensing unit disposed in the housing, the sensing unit being attached to a first surface of the housing that faces the battery cell stack and a second surface that is the outer surface opposite the first surface.

[0019] The sensing unit may be configured to surround an outer periphery of one side of the housing, and may be electrically connected to the bus bar on a second surface of the housing.

[0020] The width of the electrode lead may be 50% to 80% of the height of the housing.

[0021] The width of the electrode lead may be 60% to 80% of the overall width of the pouch-type battery cell.

[0022] The sensing unit may be a FPCB.

[0023] As part of the sensing unit, a terminal connector can be coupled to a portion attached to the second surface of the housing.

[0024] The terminal connector can be mounted so that its width direction is the same as the width direction of the housing.

[0025] The present invention also provides an electronic device including the battery module as an energy source.

[0026] Furthermore, the present invention can also be provided in the form of a combination of various means for solving the above problems. Effect of the Invention

[0027] As described above, the present invention can significantly reduce the heat generation phenomenon that is a problem during fast charging by using electrode leads that are wider than the size of the electrodes.

[0028] In addition, since the terminal connector is coupled to the sensing unit so that the width direction of the terminal connector is the same as the width direction of the housing, a large width of the electrode lead can be ensured.

[0029] In addition, since the sensing unit includes a bent shape, the sensing unit can be attached to both sides of the housing, thereby ensuring a large size of the sensing unit, and thus enabling sensing of the states of a large number of battery cells.

[0030] In this way, the present invention provides a structure capable of increasing the width of the electrode leads while sensing a large number of battery cells, thereby preventing problems such as reduced life span and reduced output of the battery module due to heat generation that can be an issue during fast charging. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a partial perspective view of a conventional battery module. [Diagram 2] FIG. 2 is a partial perspective view of a battery module according to the present invention. [Diagram 3] FIG. 3 is a partially enlarged view of FIG. [Figure 4] 4 is a partially enlarged view of the battery module of FIG. 3 as viewed inward. FIG. [Diagram 5] 2 is a plan view of an electrode assembly in which an electrode lead is connected to an electrode tab. FIG. [Figure 6] FIG. 2 is a plan view of a pouch-type battery cell. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings, which are provided to enable a person having ordinary skill in the art to which the present invention pertains to easily carry out the present invention. However, in describing the operation principle of the preferred embodiment of the present invention in detail, detailed description of related well-known functions or configurations will be omitted if it is determined that such detailed description may unnecessarily obscure the gist of the present invention.

[0033] In addition, the same reference numerals are used throughout the drawings for parts having similar functions and actions. Throughout the specification, when a part is said to be connected to another part, this includes not only the case where the part is directly connected to another part, but also the case where the part is indirectly connected via another element between the two parts. In addition, when a part includes a certain component, it does not mean that the other component is excluded, but that the part may further include the other component, unless otherwise specified.

[0034] Furthermore, descriptions that limit or add specific elements are applicable to all inventions and are not limited to a particular invention unless otherwise specified.

[0035] Furthermore, throughout the description of the present invention and the claims, the singular includes the plural unless otherwise stated.

[0036] In addition, throughout the description of the present invention and the claims, unless otherwise specified, "or" includes "and." Therefore, "including A or B" means three cases: including A, including B, or including both A and B.

[0037] Furthermore, all numerical ranges include the endpoints and all intermediate values ​​therebetween unless expressly stated to the contrary.

[0038] The invention will now be described on the basis of detailed embodiments with reference to the drawings.

[0039] FIG. 2 is a partial perspective view of a battery module according to the present invention, FIG. 3 is a partial enlarged view of FIG. 2, and FIG. 4 is a partial enlarged view of the battery module of FIG. 3 as viewed inwardly.

[0040] 2 to 4, the battery module according to the present invention includes a battery cell stack consisting of a plurality of pouch-type battery cells 100 stacked along the x direction, a bus bar 200 electrically connected to an electrode lead 110 protruding from the pouch-type battery cell 100, a housing 300 for fixing the bus bar 200, and a sensing unit 400 disposed in the housing.

[0041] The housing 300 includes a first surface facing the battery cell stack and a second surface which is the outer surface opposite to the first surface, and the sensing unit 400 has a folded shape and is structured to be attached to the first surface and the second surface.

[0042] Specifically, the sensing unit 400 may have a shape surrounding one side of the outer periphery of the housing 300. For example, in Figs. 2 to 4, the sensing unit 400 is attached in a shape surrounding the outer periphery of the end of the housing 300 in the y direction.

[0043] Therefore, compared to the structure in which the sensing units are arranged only on the second surface along the y direction in the conventional battery module shown in FIG. 1, the length of the sensing units in the y direction can be reduced by about 50%. In this way, the width W of the electrode lead is reduced by the amount of the reduction in the length of the sensing units in the y direction. L In this case, the length in the y direction can be increased.

[0044] Considering that the pouch-type battery cell is a structure for maximizing the width of the electrode leads, it may be a bidirectional battery cell in which the positive and negative leads protrude in opposite directions. The electrode leads extend outward through slits in the bus bar and are bent to be coupled to the bus bar.

[0045] FIG. 1 shows a configuration in which the positive electrode lead and the negative electrode lead are connected to the bus bar so as not to overlap, and FIG. 2 shows a configuration in which the positive electrode lead and the negative electrode lead are connected to the bus bar while being arranged so as to overlap.

[0046] That is, various types of connection between the electrode lead and the bus bar can be applied.

[0047] The sensing unit 400 is an FPCB having a circuit printed on a board made of an electrically insulating material, and the FPCB, which is the sensing unit 400, is electrically connected to the bus bar 200 on the second surface of the housing, and can be configured to sense the temperature, voltage, and current of each of the plurality of pouch-type battery cells 100 that constitute the battery module by being connected to them.

[0048] The electrode lead 110 according to the present invention has a width W L For example, the width W of the electrode lead is larger than that of the conventional battery module. L may have a size of 50% to 80% of the height H of the housing. Specifically, when the height H of the housing is 110 mm, an electrode lead with a width of 60 mm to 80 mm may be used. Compared to a conventional configuration in which an electrode lead with a width of 40 mm to 50 mm is used when the height of the housing is 110 mm, a configuration in which the width of the electrode lead is increased by about 20% to 100% may be applied.

[0049] A terminal connector 500 may be attached to the sensing unit 400 as a connection part for transmitting data measured by the sensing unit of the battery module. FIGS. 2 to 4 show a form in which the terminal connector 500 is coupled to the sensing unit 400 disposed on the second surface of the housing. The terminal connector 500 has a form that is long in one direction. In this case, the width W of the long terminal connector is 100 mm. 500 If the direction of the electrode lead is parallel to the y direction, the width W L Therefore, the terminal connector 500 has a terminal connector width W 500The direction of the arrows is the same as the x direction, which is the width direction of the housing.

[0050] FIG. 5 is a plan view of an electrode assembly in which an electrode lead is connected to an electrode tab.

[0051] 5, a plate-shaped electrode plate 121 with an electrode tab 120 protruding from the right side is shown. The electrode plates 121 may have a stacked form of two or more, and the number of electrode tabs 120 may be configured to be the same as the number of stacked electrode plates 121.

[0052] The electrode assembly may be a stack / folding type electrode assembly in which a unit cell consisting of a bicell or monocell is arranged on a separator sheet and then wound up, or a lamination / stack type electrode assembly in which the unit cells are stacked with a separator interposed therebetween.

[0053] The bicell has a structure in which three electrode plates, each having a different polarity between adjacent electrodes, are stacked with a separator between them, and the monocell has a structure in which two electrode plates, each having a different polarity, are stacked with a separator between them.

[0054] Width W of electrode tab 120 protruding from electrode plate 121 T is the width W of the electrode lead 110 L Generally, considering that the electrode tabs 120 extend 5 mm further in the width direction from the electrode lead 110, in a structure in which the electrode lead width increases, the width of the electrode tabs may also increase accordingly.

[0055] For example, the width W of the electrode lead 110 L When the width W of the electrode tab 120 is 60mm to 80mm, T can be between 70mm and 90mm.

[0056] In other words, the pouch-type battery cell used in the present invention uses electrode tabs that are larger than the electrode tabs of conventional electrode assemblies, and by combining them with electrode leads having a larger width, it is possible to reduce the heat generation phenomenon that is a problem during fast charging.

[0057] FIG. 6 is a plan view of a pouch-type battery cell.

[0058] Referring to FIG. 6, there is shown a pouch-type battery cell 100 in which an electrode assembly is housed in a pouch-type battery case, and an electrode lead 110 protrudes to the right side of the drawing.

[0059] In the pouch-type battery cell 100, the width W of the electrode lead L is the overall width W of the pouch-type battery cell 100 C Specifically, the width of the battery cell W C In other words, if the total width W of the battery cell is 100 mm, the electrode lead width can be 60 mm to 80 mm. C When the width of the electrode lead is 100 mm, the width of the electrode lead can be increased by about 20% to 100% compared to when the electrode lead has a width of 40 mm to 50 mm.

[0060] In this way, the present invention can increase the width of the electrode lead by adding a bent sensing unit and aligning the arrangement direction of the terminal connector with the width direction of the housing, thereby minimizing heat generation in the battery cell during fast charging and improving the performance of the battery cell.

[0061] The present invention provides an electronic device including the battery module as an energy source.

[0062] The electronic device may be an electric vehicle, a hybrid electric vehicle, an electric bicycle, an electric cart, or a power storage device. These may have known forms, so detailed descriptions of their structures will be omitted.

[0063] Those skilled in the art will appreciate that various applications and modifications within the scope of the present invention are possible based on the above content. [Explanation of symbols]

[0064] 100 pouch type battery cells 110 Electrode Lead 120 Electrode tab 121 Electrode plate 200 Busbar 300 Housing 400 Sensing Unit 500 Terminal Connector H Housing height W C Overall width of pouch-type battery cell W L Electrode Lead Width W T Electrode Tab Width W 500 Terminal Connector Width

Claims

1. a battery cell stack in which pouch-type battery cells are stacked; a bus bar coupled to an electrode lead of the pouch-type battery cell; a housing for fixing the bus bar; A sensing unit disposed in the housing; Including, the sensing unit is a flexible printed circuit board (FPCB) having a bent shape so as to be attached to both a first surface of the housing facing the battery cell stack and a second surface which is an outer surface opposite to the first surface, The sensing unit has a shape surrounding one side of the outer periphery in a height direction of the housing. Battery module.

2. The sensing unit is electrically connected to the bus bar on a second surface of the housing. The battery module according to claim 1 .

3. The width of the electrode lead is 50% to 80% of the height of the housing. The battery module according to claim 1 .

4. The width of the electrode lead is 60% to 80% of the overall width of the pouch-type battery cell. The battery module according to claim 1 .

5. A terminal connector is coupled to a portion of the sensing unit that is attached to the second surface of the housing. The battery module according to claim 1 .

6. The terminal connector is attached so that its width direction is the same as the width direction of the housing. The battery module according to claim 5 .

7. An electronic device comprising the battery module according to any one of claims 1 to 6 as an energy source.

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