Battery pack

Abstract

A battery pack is disclosed. The battery pack according to one embodiment of the present invention comprises: a case having an open lower side and providing an inner space; a bottom cover coupled to the lower portion of the case; a PCB accommodated in the case and positioned on the bottom cover; and a plurality of battery cells accommodated in the case and positioned on the PCB.

Description

battery pack

[0001] The present invention relates to a battery pack.

[0002] This application claims priority to Korean Patent Application No. 10-2023-0167311, filed on November 27, 2023, the entire contents of which are disclosed in the specification and drawings of which are incorporated herein by reference.

[0003] As demand for portable electronic products such as laptops, video cameras, and mobile phones rapidly increases and the commercialization of robots and electric vehicles becomes more widespread, research into high-performance secondary batteries capable of repeated charging and discharging is actively underway.

[0004] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries are receiving attention for their advantages of being able to charge and discharge freely, having a very low self-discharge rate, and having a high energy density, as they have almost no memory effect compared to nickel-based secondary batteries.

[0005] These lithium secondary batteries primarily use lithium oxide and carbon materials as the positive and negative electrode active materials, respectively. Lithium secondary batteries comprise an electrode assembly comprising positive and negative plates coated with the positive and negative electrode active materials, respectively, with a separator interposed between them, and an outer case, i.e., a battery case, that seals and encloses the electrode assembly together with an electrolyte.

[0006] In general, lithium secondary batteries can be classified into can-type secondary batteries in which the electrode assembly is built into a metal can and pouch-type secondary batteries in which the electrode assembly is built into a pouch of an aluminum laminate sheet, depending on the shape of the outer packaging material.

[0007] Recently, secondary batteries have been widely used for power and energy storage, not only in small devices like portable electronic devices, but also in medium- to large-scale devices like electric scooters, electric vehicles, and energy storage systems (ESS). Multiple such secondary batteries can be electrically connected to form a single battery pack.

[0008] However, when multiple secondary batteries (battery cells) or battery modules are densely packed in a confined space, they can be vulnerable to thermal events. Specifically, if a thermal runaway event occurs in a single battery cell, high-temperature gases, flames, and heat can be generated. If these gases, flames, or heat are transferred to other battery cells within the same battery module, an explosive chain reaction, such as thermal propagation, can occur. This chain reaction can not only cause fire or explosion in the battery pack or module in question, but can also trigger fires or explosions in other battery modules.

[0009] Moreover, for medium- to large-sized battery packs, such as those used in electric scooters or electric vehicles, the risk of thermal chain reaction may be further increased due to the inclusion of a large number of battery cells or battery modules to increase output and / or capacity. In particular, battery packs used in electric scooters may be configured to be replaceable as a unit. For example, a battery pack requiring charging may be removed from the electric scooter, and a fully charged battery pack may be installed in the scooter. In this case, the removed battery pack may be exposed to external impact or flame. Therefore, a structure is needed to prevent or delay thermal events from occurring within the battery pack.

[0010] The present invention aims to solve the above-mentioned problems and other problems.

[0011] Another object of the present invention may be to provide a battery pack including a structure capable of blocking or delaying external heat from being transferred to a battery cell.

[0012] In order to achieve the above-described purpose, a battery pack according to one embodiment of the present invention may include a case having an open bottom and providing an internal space; a bottom cover coupled to a bottom of the case; a PCB accommodated inside the case and positioned above the bottom cover; and a plurality of battery cells accommodated inside the case and positioned above the PCB.

[0013] Additionally, the bottom cover may include a PBT material or a glass fiber material.

[0014] Additionally, the battery pack may further include a main frame housed inside the case and positioned above the PCB.

[0015] Additionally, the plurality of battery cells can be mounted on the main frame.

[0016] Additionally, the battery pack may further include a phase change material that fills the interior of the main frame.

[0017] Additionally, the phase change material may include paraffin.

[0018] Additionally, the battery pack may further include a barrier covering the PCB.

[0019] Additionally, the barrier may entirely surround the PCB.

[0020] Additionally, the barrier may include a PBT material or a glass fiber material.

[0021] Additionally, the barrier may include an upper barrier positioned between the plurality of battery cells and the PCB, and covering an upper surface of the PCB.

[0022] Additionally, the barrier may include a lower barrier positioned between the bottom cover and the PCB and covering a lower surface of the PCB.

[0023] Additionally, the battery pack may further include a BMS provided on the PCB and electrically connected to the plurality of battery cells.

[0024] A means of transportation according to one aspect of the present invention includes a battery pack of the present invention.

[0025] According to at least one of the embodiments of the present invention, the thermal safety of a battery pack can be improved.

[0026] According to at least one of the embodiments of the present invention, occurrence of a thermal event in a battery pack due to an external impact or flame can be suppressed.

[0027] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0028] FIG. 1 is a drawing showing a battery pack according to one embodiment of the present invention.

[0029] Fig. 2 is a diagram showing a partial configuration of the battery pack of Fig. 1 in isolation.

[0030] FIG. 3 is a drawing showing a part of the configuration of the battery pack of FIG. 1.

[0031] Fig. 4 is a diagram showing a partial configuration of the battery pack of Fig. 3 in isolation.

[0032] FIG. 5 is a drawing showing a cell module assembly of a battery pack according to one embodiment of the present invention.

[0033] Fig. 6 is a drawing showing a partial configuration of the cell module assembly of Fig. 5 in isolation.

[0034] Fig. 7 is a drawing showing a part of the configuration of the cell module assembly of Fig. 5.

[0035] Fig. 8 is a drawing showing a partial configuration of the cell module assembly of Fig. 7 in isolation.

[0036] FIGS. 9 and 10 are drawings showing a partial configuration of the cell cell module assembly of FIG. 8 in isolation.

[0037] Fig. 11 is a drawing showing a part of a cross-sectional configuration along the cutting line B-B' of Fig. 7.

[0038] FIG. 12 is a drawing showing a controller of a battery pack according to one embodiment of the present invention.

[0039] Fig. 13 is a diagram showing a partial configuration of the controller of Fig. 12 in isolation.

[0040] Fig. 14 is a drawing showing a part of a cross-sectional configuration along the cutting line C-C' of Fig. 12.

[0041] Fig. 15 is a drawing showing a part of a cross-sectional configuration along the cutting line A-A' of Fig. 1.

[0042] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0043] Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are only the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention, and it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0044] FIG. 1 is a drawing showing a battery pack according to an embodiment of the present invention. FIG. 2 is a drawing showing a partial configuration of the battery pack of FIG. 1 in isolation. Referring to FIGS. 1 and 2, a battery pack according to an embodiment of the present invention may include a case (200), a bottom cover (300), a PCB (520), and a battery cell (430).

[0045] The case (200) may have an open bottom and provide an internal space. Additionally, the case (200) may have an open top. The case (200) may have a rectangular parallelepiped shape. The case (200) may include a metal material. For example, the case (200) may include aluminum. The case (200) may have a rectangular parallelepiped shape with the upper and lower surfaces open.

[0046] The bottom cover (300) can be joined, fastened, fixed or attached to the lower or lower surface of the case (200). The bottom cover (300) can cover the opening of the case (200).

[0047] The PCB (520) can be accommodated in the internal space of the case (200). The PCB (520) can be positioned above the bottom cover (300). The PCB (520) can have a plate shape. In addition, the PCB (520) can face the bottom cover (300).

[0048] A plurality of battery cells (430) may be provided. In this case, the battery cells (430) may refer to secondary batteries. The battery cells (430) may have a cylindrical shape. A plurality of battery cells (430) may be accommodated inside the case (200). The plurality of battery cells (430) may be positioned on the PCB (520).

[0049] According to this configuration of the present invention, a plurality of battery cells (430) can be protected from the PCB (520) and the bottom cover (300). For example, when the battery pack is exposed to an external flame, the bottom cover (300) and the PCB (520) can block or delay the battery cells (430) from being exposed to the flame or heat. As a result, the thermal safety of the battery pack can be improved.

[0050] Referring to FIGS. 1 and 2, the bottom cover (300) of the battery pack according to one embodiment of the present invention may include a PBT (Polybutylene Terephthalate) material. The PBT material may have strong heat resistance. In addition, the bottom cover (300) may include a glass fiber material. The glass fiber material may have strong heat resistance.

[0051] According to this configuration of the present invention, the flame resistance of the bottom cover (300) can be improved. As a result, the thermal safety of the battery pack can be improved.

[0052] Referring to FIGS. 1 and 2, a battery pack according to an embodiment of the present invention may include a top cover (100). The top cover (100) may be coupled, fastened, fixed, or attached to the upper or upper surface of the case (200). The top cover (100) may cover an opening of the case (200).

[0053] Fig. 3 is a drawing showing a part of the configuration of the battery pack of Fig. 1. Fig. 4 is a drawing showing a part of the configuration of the battery pack of Fig. 3 in isolation.

[0054] Referring to FIGS. 3 and 4, a battery pack according to an embodiment of the present invention may include a cell module assembly (400) and a controller (500). The cell module assembly (400) may include a plurality of battery cells (430). The cell module assembly (400) may be accommodated inside a case (200).

[0055] The controller (500) may include a PCB (520). The controller (500) may be accommodated inside the case (200). The controller (500) may be located below the cell module assembly (400). Alternatively, the controller (500) may be coupled, fastened, fixed, or attached to the bottom or lower surface of the cell module assembly (400). The controller (500) may monitor the status of a plurality of battery cells (430). In addition, the controller (500) may control charging and discharging of the plurality of battery cells (430).

[0056] FIG. 5 is a drawing showing a cell module assembly (400) of a battery pack according to one embodiment of the present invention. FIG. 6 is a drawing showing a partial configuration of the cell module assembly (400) of FIG. 5 in isolation. FIG. 7 is a drawing showing a partial configuration of the cell module assembly (400) of FIG. 5. FIG. 8 is a drawing showing a partial configuration of the cell module assembly (400) of FIG. 7 in isolation.

[0057] Referring to FIGS. 5 to 8, a cell module assembly (400) according to an embodiment of the present invention may have a rectangular parallelepiped shape. The cell module assembly (400) may include a first sub-assembly (410) and a second sub-assembly (420). The first sub-assembly (410) and the second sub-assembly (420) may each include a plurality of battery cells (430). The first sub-assembly (410) and the second sub-assembly (420) may be arranged, aligned, or positioned in the left-right direction or the Y-axis direction.

[0058] The first sub-assembly (410) and the second sub-assembly (420) may be mutually fastened, coupled, or fixed. The first sub-assembly (410) and the second sub-assembly (420) may be physically or electrically connected.

[0059] The cell module assembly (400) may include an insulating cover (401). The insulating cover (401) may cover an outer surface of the cell module assembly (400). Alternatively, the insulating cover (401) may cover an outer surface of the first sub-assembly (410) and the second sub-assembly (420). The insulating cover (401) may electrically insulate the first sub-assembly (410) and the second sub-assembly (420) from the case (200).

[0060] The first sub-assembly (410) may include a first outer frame (411) and a first inner frame (412). The first outer frame (411) and the first inner frame (412) may be arranged, aligned, or positioned in the left-right direction or the Y-axis direction. The first outer frame (411) and the first inner frame (412) may be mutually fastened, coupled, or fixed. The first outer frame (411) and the first inner frame (412) may form the exterior of the first sub-assembly (410).

[0061] The second sub-assembly (420) may include a second outer frame (421) and a second inner frame (422). The second outer frame (421) and the second inner frame (422) may be arranged, aligned, or positioned in the left-right direction or the Y-axis direction. The second outer frame (421) and the second inner frame (422) may be mutually fastened, coupled, or fixed. The second outer frame (421) and the second inner frame (422) may form the exterior of the second sub-assembly (420).

[0062] The first inner frame (412) and the second inner frame (422) can be arranged, aligned, or positioned in the left-right direction or the Y-axis direction. The first inner frame (412) and the second inner frame (422) can be mutually fastened, coupled, or fixed.

[0063] FIGS. 9 and 10 are isolate views illustrating a portion of the cell cell module assembly (400) of FIG. 8. FIG. 11 is a view illustrating a portion of a cross-sectional configuration taken along the cutting line B-B' of FIG. 7. Referring to FIGS. 8 to 11, a battery pack according to an embodiment of the present invention may include a main frame.

[0064] The main frame may be used as a general term for the first outer frame (411), the first inner frame (412), the second inner frame (422), and the second outer frame (421). The main frame may form the exterior of the cell module assembly (400). The main frame may be accommodated inside the case (200) and positioned above the PCB (520).

[0065] A plurality of battery cells (430) may be mounted on the main frame. At least some of the plurality of battery cells (430) may be accommodated in the first outer frame (411) and the first inner frame (412). The plurality of battery cells (430) may extend in the left-right direction or the Y-axis direction. The left portion of the plurality of battery cells (430) may be accommodated in the first outer frame (411). The right portion of the plurality of battery cells (430) may be accommodated in the first inner frame (412).

[0066] Additionally, at least a portion of the plurality of battery cells (430) may be accommodated in the second outer frame (421) and the second inner frame (422). The plurality of battery cells (430) may extend in the left-right direction or the Y-axis direction. The left portion of the plurality of battery cells (430) may be accommodated in the second inner frame (422). The right portion of the plurality of battery cells (430) may be accommodated in the second outer frame (421).

[0067] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. A plurality of battery cells (430) can be protected by the main frame. For example, if the battery pack is exposed to an external flame, the main frame can block or delay the battery cells (430) from being exposed to the flame or heat.

[0068] Referring to FIGS. 8 to 11, a battery pack according to an embodiment of the present invention may include a phase change material that fills the interior of a main frame. The phase change material (PCM, not shown) may fill the interior of a cell module assembly (400). For example, the phase change material may fill the interior of a first sub-assembly (410) or a second sub-assembly (420). In addition, the phase change material may fill the interior of a first outer frame (411) or a first inner frame (412). In addition, the phase change material may be filled between a plurality of battery cells (430). In addition, the phase change material may fill the interior of a second outer frame (421) or a second inner frame (422).

[0069] Phase change materials can exist in a solid state at room temperature. They can absorb heat and change into a liquid state. By absorbing heat, phase change materials can reduce or block heat transfer to the battery cell (430).

[0070] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. By absorbing heat from the phase change material, heat transferred to the battery cell (430) can be reduced or blocked. Furthermore, the rate of heat transfer to the battery cell (430) can be delayed.

[0071] Referring to FIGS. 8 to 11, the phase change material of the battery pack according to one embodiment of the present invention may include paraffin.

[0072] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. Paraffin absorbs heat, thereby reducing or blocking heat transferred to the battery cells (430). Furthermore, the rate of heat transfer to the battery cells (430) can be delayed.

[0073] Fig. 12 is a drawing showing a controller (500) of a battery pack according to an embodiment of the present invention. Fig. 13 is a drawing showing a partial configuration of the controller (500) of Fig. 12 in isolation. Fig. 14 is a drawing showing a part of a cross-sectional configuration taken along the cutting line C-C' of Fig. 12. Fig. 15 is a drawing showing a part of a cross-sectional configuration taken along the cutting line A-A' of Fig. 1.

[0074] Referring to FIGS. 12 to 15, a battery pack according to an embodiment of the present invention may include a barrier. The controller (500) may include the barrier. The barrier may form the exterior of the controller (500). The barrier may have a rectangular parallelepiped shape. The barrier may cover the PCB (520). The PCB (520) may not be exposed to the outside due to the barrier. The barrier may be used collectively as an upper barrier (510) and a lower barrier (530).

[0075] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. A plurality of battery cells (430) can be protected by the barrier and the PCB (520). For example, when the battery pack is exposed to an external flame, the barrier and the PCB (520) can block or delay the battery cells (430) from being exposed to the flame or heat.

[0076] Referring to FIGS. 12 to 15, a barrier according to an embodiment of the present invention may entirely surround a PCB (520). The barrier may cover the lower and upper surfaces of the PCB (520). In addition, the barrier may function as a case that accommodates the PCB (520).

[0077] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. Since the barrier covers the upper and lower surfaces of the PCB (520), the exposure of the battery cell (430) to flame or heat can be more reliably blocked or delayed.

[0078] Referring to FIGS. 12 to 15, the barrier of a battery pack according to an embodiment of the present invention may include a PBT material. The PBT material may have high heat resistance. Furthermore, the barrier may include a glass fiber material. The glass fiber material may have high heat resistance.

[0079] According to this configuration of the present invention, the flame resistance of the bottom cover (300) can be improved. As a result, the thermal safety of the battery pack can be improved.

[0080] Referring to FIGS. 12 to 15, a barrier of a battery pack according to an embodiment of the present invention may include an upper barrier (510) positioned between a plurality of battery cells (430) and a PCB (520) and covering an upper surface of the PCB (520).

[0081] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. Since the barrier covers the upper surface of the PCB (520), the battery cell (430) can be more reliably blocked or delayed from being exposed to flame or heat.

[0082] Referring to FIGS. 12 to 15, a barrier of a battery pack according to an embodiment of the present invention may include a lower barrier (530) positioned between a bottom cover (300) and a PCB (520) and covering a lower surface of the PCB (520). The barrier may include an upper barrier (510) and a lower barrier (530).

[0083] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. Since the barrier covers the lower surface of the PCB (520), the battery cell (430) can be more reliably blocked or delayed from being exposed to flame or heat.

[0084] Referring to FIGS. 12 to 15, a controller (500) of a battery pack according to an embodiment of the present invention may include a barrier, a PCB (520), and a wire assembly. The wire assembly may be provided on the lower surface of the lower barrier (530). The wire assembly may electrically connect the PCB (520) to input / output terminals of the battery pack, battery cells (430), or various electronic components.

[0085] Referring to FIGS. 12 to 15, a battery pack according to an embodiment of the present invention may include a BMS mounted on a PCB (520) and electrically connected to a plurality of battery cells (430). The BMS may be positioned on the PCB (520). The BMS may monitor information such as the temperature or charge level of the plurality of battery cells (430).

[0086] According to this configuration of the present invention, the thermal safety of the battery pack can be improved. In particular, when the lower portion of the battery pack is exposed to flame, the bottom cover (300), lower barrier (530), PCB (520) equipped with the BMS, upper barrier (510), main frame, and phase change material can block or delay the battery cell (430) from being exposed to flame or high heat.

[0087] In addition, the battery pack according to the present invention may further include various components, for example, components of a battery pack known at the time of filing of the present invention, such as a BMS, a bus bar, a relay, a current sensor, etc.

[0088] A means of transportation according to the present invention may include the battery pack according to the present invention described above. The battery pack according to the present invention may be applied to an electric scooter or an automobile, such as an electric vehicle or hybrid vehicle. Furthermore, the automobile according to the present invention may further include, in addition to the battery pack, various other components included in a scooter or automobile, such as a body, a motor, and a control device such as an electronic control unit (ECU).

[0089] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back are used in this specification, it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0090] As described above, although the present invention has been described by limited embodiments and drawings, the present invention is not limited thereto, and various modifications and variations are possible by a person having ordinary skill in the art to which the present invention pertains within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below.

Claims

1. A case with an open bottom and an internal space; A bottom cover coupled to the lower portion of the above case; A PCB housed inside the case and positioned above the bottom cover; and A battery pack comprising a plurality of battery cells housed inside the case and positioned above the PCB.

2. In paragraph 1, The above bottom cover, A battery pack containing PBT material or glass fiber material.

3. In paragraph 1, Further comprising a main frame accommodated inside the case and positioned above the PCB, The above plurality of battery cells, A battery pack mounted on the above main frame.

4. In paragraph 3, A battery pack further comprising a phase change material filling the interior of the main frame.

5. In paragraph 4, Phase change materials are, Battery pack containing paraffin.

6. In paragraph 1, A battery pack further comprising a barrier covering the above PCB.

7. In paragraph 6, The above barrier is, A battery pack that completely surrounds the above PCB.

8. In paragraph 6, The above barrier is, A battery pack containing PBT material or glass fiber material.

9. In paragraph 6, The above barrier is, A battery pack comprising an upper barrier positioned between the plurality of battery cells and the PCB, the upper barrier covering an upper surface of the PCB.

10. In paragraph 6, The above barrier is, A battery pack including a lower barrier positioned between the bottom cover and the PCB, the lower barrier covering a lower surface of the PCB.

11. In paragraph 1, A battery pack further comprising a BMS provided on the PCB and electrically connected to the plurality of battery cells.

12. A means of transportation comprising a battery pack according to any one of claims 1 to 11.

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