Components

Abstract

An appliance for use with a battery pack (10) having multiple batteries (50) and a housing (90) having an outlet (41) and a sealing member (43) that blocks the outlet (41) and houses the multiple batteries (50), and having the function of venting gas from the housing (90), comprises: a base (61) that supports the battery pack; a gas inlet hole (41) that is a hole formed in the base (61) and is formed at a position overlapping with the outlet hole (41) of the battery pack; an outlet pipe (64) that is a ventilation path formed in the base (61) and communicates with the gas inlet hole (41) for guiding the gas vented from the battery pack (10) to the outside of the appliance; and a pressing part (63) that protrudes from the gas inlet hole (61) and presses the sealing member (43) of the battery pack (10).

Description

Technical Field

[0001] This disclosure relates to a battery pack and an apparatus having the function of venting gas from the battery pack. Background Technology

[0002] Non-aqueous electrolyte secondary batteries, such as lithium-ion batteries, are sometimes used in the form of battery packs, where multiple batteries are electrically connected and housed in a casing. In the event of an abnormality within this battery pack, a large amount of high-temperature flammable gas may be generated. If this gas is not properly vented from the battery pack, there is a danger that the internal pressure of the battery pack may rise, leading to damage to the battery pack casing. Normally, a sealed battery pack casing is required to prevent water and dust from entering the battery pack; however, in the event of a battery abnormality and a rise in internal pressure, it is necessary to quickly vent the gas to the outside.

[0003] Most battery malfunctions occur during charging when the battery is installed in the charger. For example, Patent Document 1 discloses a charger that keeps the vent of the battery pack open during charging.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Utility Model Application Publication No. 6-64360 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] However, in the charger described in Patent Document 1, the following situation can be envisioned: gas discharged from the battery pack becomes trapped in the space between the battery pack and the charger, preventing the gas from the battery pack from escaping smoothly. Furthermore, charging electrode contacts are located in the space between the battery pack and the charger. If the gas is violently discharged, there is a possibility of poor contact at the contacts, and since the generated gas is flammable, there is sometimes a risk of fire.

[0009] The purpose of this disclosure is to provide a means for the smooth and safe discharge of gas from the battery pack when a battery malfunctions and the internal pressure of the battery pack rises.

[0010] Solution for solving the problem

[0011] The battery pack disclosed herein includes: a plurality of batteries; and a housing that houses the plurality of batteries. The housing has: a discharge port that extends through the housing; a partition wall that is formed inside the housing in a bottomed cylindrical shape to surround the discharge port; a sealing member disposed within the cylinder of the partition wall and blocking the discharge port; and a force-applying member disposed within the cylinder of the partition wall and applying force to the sealing member in the direction of the discharge port. The partition wall has a vent hole that forms a gas discharge path together with the discharge port. The sealing member is configured to move inward when pressed from the outside of the housing to open the discharge port.

[0012] The disclosed appliance with gas discharge function is applied to a battery pack having multiple batteries and a housing for storing the multiple batteries. The housing has a discharge port and a sealing member for blocking the discharge port. The appliance includes: a base for supporting the battery pack; a gas inlet port, which is a hole formed in the base and is formed at a position overlapping with the discharge port of the battery pack; a discharge pipe, which is a ventilation path formed in the base and communicates with the gas inlet port for guiding the gas discharged from the battery pack to the outside of the appliance; and a pressing part, which protrudes from the gas inlet port and presses the sealing member of the battery pack.

[0013] The effects of the invention

[0014] According to the battery pack and the device with gas venting function disclosed herein, when the internal pressure of the battery pack rises due to a battery malfunction, gas can be smoothly and safely vented from the battery pack. Attached Figure Description

[0015] Figure 1 This is an external view of the battery pack and charger according to an embodiment of the present disclosure.

[0016] Figure 2 yes Figure 1 A sectional view of the battery pack along line AA.

[0017] Figure 3 This is a partial cross-sectional view showing the charger of this disclosure activating the battery pack discharge mechanism.

[0018] Figure 4 This is a partial cross-sectional view showing the battery pack of this disclosure being mounted on an electrical device. Detailed Implementation

[0019] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, specific shapes, materials, orientations, values, etc., are provided for ease of understanding of the embodiments of the present disclosure and can be appropriately changed according to the application, purpose, specifications, etc.

[0020] (First Embodiment)

[0021] Figure 1This is an external view of the battery pack 10 according to the first embodiment of this disclosure. Figure 2 yes Figure 1 The AA-line sectional view in the diagram. (Example) Figure 1 and Figure 2 As shown, the battery pack 10 includes a housing 90 and a plurality of batteries 50. The housing 90 has: a housing body 20 that houses the plurality of batteries 50; and a housing cover 30 and a housing bottom 40 that block the openings of the housing body 20. The housing 90 is constructed such that each opening of the housing body 20, which is formed in a rectangular cylindrical shape, is closed by the housing cover 30 and the housing bottom 40, respectively, thus sealing the internal space. Therefore, water and dust will not enter the interior of the housing 90. Hereinafter, for ease of explanation, the housing cover 30 side of the housing 90 is designated as the upper side, the housing bottom 40 side of the housing 90 is designated as the lower side, and the orientation of the housing cover 30, housing body 20, and housing bottom 40 is designated as the vertical direction.

[0022] Multiple batteries 50 are electrically connected to each other to form a battery pack. The battery pack is configured, for example, to have a structure in which multiple battery cells are connected in series, and to output a voltage suitable for the device being used. These battery cells are composed of multiple batteries 50 connected in parallel. The batteries 50 are, for example, cylindrical batteries. Furthermore, in Figure 2 The example shown is a cylindrical battery as battery 50, but the battery is not limited to cylindrical batteries; it can also be a prismatic battery, a laminated battery, etc. Furthermore, battery 50 can be either an aqueous battery or a non-aqueous battery. As an example of a non-aqueous battery, a lithium-ion battery can be cited.

[0023] Battery 50 is a cylindrical battery having a bottomed cylindrical outer can and a sealing body that blocks the opening of the outer can. An insulating gasket is provided between the outer can and the sealing body. In cylindrical batteries, the sealing body is typically the positive terminal, and the outer can is the negative terminal. An vent valve is provided in the sealing body to release gas when the internal pressure of battery 50 rises due to an abnormality. Alternatively, the vent valve may be located at the bottom of the outer can.

[0024] Multiple batteries 50 are housed within a retainer 51 within a housing 90. The retainer 51 secures the arrangement of the batteries 50 and maintains the battery pack's configuration. Additionally, the battery pack 10 may include, for example, a terminal plate for electrically connecting the multiple batteries 50. The terminal plate includes a positive terminal plate electrically connected to the positive terminal (i.e., the sealing body) of each battery 50 and a negative terminal plate electrically connected to the negative terminal (i.e., the outer can) of each battery 50. The terminal plate may also be integrated with the retainer 51.

[0025] The housing 90 is provided with external terminals (not shown) that are electrically connected to each battery 50. These external terminals, for example, are located at the bottom 40 of the housing and are used as terminals for supplying DC voltage when assembled into a device that carries the battery pack 10. Additionally, the external terminals are also used when charging the battery pack 10 (batteries 50).

[0026] Reference Figures 1-2 The gas venting function of battery pack 10 is described in detail.

[0027] like Figures 1-2 As shown, the housing 90 constituting the battery pack 10 has a housing body 20, a housing cover 30, and a housing bottom 40, and is formed into a rectangular parallelepiped shape that is longer in the vertical direction. The housing 90 can be made of resin or metal. As described above, the housing body 20 is formed into a rectangular tube shape with openings at both the top and bottom. The housing 90 has a structure in which the opening at the upper end of the housing body 20 is blocked by the housing cover 30, and the opening at the lower end of the housing body 20 is blocked by the housing bottom 40. Inside the sealed housing body 20, multiple batteries 50 are arranged with the sealing body facing the housing cover 30, but the number and arrangement of the batteries are not limited. Figure 2 The example is shown.

[0028] A discharge hole 41 is formed through the bottom 40 of the housing. The discharge hole 41 is, for example, a circular hole. Inside the bottom 40 of the housing, a bottomed cylindrical partition wall 44 is formed along the direction of the housing body 20 to surround the discharge hole 41. A spring (force-applying member) 42 and a sealing member 43 are housed in the partition wall 44. The spring 42 presses the sealing member 43 toward the discharge hole 41. The sealing member 43, in the top view, has the same shape as the discharge hole 41 but is slightly larger, blocking the discharge hole 41. In the partition wall 44, with the sealing member 43 pressed, a vent hole 45 is formed above the discharge hole 41, at a position higher than the sealing member 43.

[0029] At the bottom of the housing 40, under normal conditions, the spring 42 applies force to the sealing member 43 to block the discharge hole 41, preventing gas from escaping from the bottom of the housing 40.

[0030] The sealing member 43 is able to be pressed in from the outside against the elastic force of the spring 42. The sealing member 43 is pressed in beyond the position of the vent 45, thereby opening the discharge hole 41 and forming a gas discharge path together with the vent 45.

[0031] Based on the above, the battery pack 10 is designed to maintain a sealed state under normal conditions, and to form a gas venting mechanism by pressing from the outside.

[0032] The sizes of the discharge port 41 and the vent port 45 are determined appropriately according to the gas discharge state. The gas discharge rate is determined by the pressure of the housing 90, the opening area of ​​the discharge port 41, and the opening area of ​​the vent port 45. Furthermore, since the discharged gas contains flammable components, it is necessary to prevent ignition when the gas is discharged from the housing 90. The inventors' research has shown that the gas discharge rate is a crucial factor in suppressing ignition; if a predetermined threshold is exceeded, the ignition suppression effect becomes higher. Therefore, it is preferable to set the opening areas of the discharge port 41 and the vent port 45 such that the gas discharge rate exceeds this threshold.

[0033] In the battery pack 10 of this embodiment, as described later, the discharge hole 41 is an opening that receives pressure from the outside, so it is preferable to adjust the opening area of ​​the vent hole 45. By appropriately setting the discharge area of ​​the vent hole 45, the discharge speed can be set.

[0034] The vent 45 may also have a portion of the partition wall 44 formed as a mesh structure. A mesh structure refers to a lattice-like or mesh-like structure, meaning a structure with periodically arranged fine-lined partitions. Furthermore, the gaps between the fine-lined partitions serve as openings for gas discharge. For example, the width of the partition is set to be smaller than the width of the opening, and the opening ratio (total area of ​​the openings) of the mesh structure is set to be greater than 50%. Additionally, it is preferable that the mesh structure is made of metal.

[0035] By forming the vents 45 with a mesh structure, smooth gas discharge is ensured, and sparks can be easily captured. The fire suppression effect is further enhanced by using a mesh structure to efficiently capture sparks.

[0036] (Second Implementation)

[0037] Next, refer to Figure 1 and Figure 3 An apparatus that has the function of venting gas from the battery pack will be described. In this embodiment, a battery pack charger will be described as an example of an apparatus.

[0038] Figure 1 A charger 60 for charging the battery pack 10 is shown. The charger 60 includes a base 61 for supporting the battery pack 10 and a connection terminal 67 for connecting to the charging terminal of the battery pack 10.

[0039] The base 61 serves as the base for supporting the battery pack 10 during charging. A gas inlet 62 is provided in the base 61. An outlet pipe 64 is provided at the lower part of the base 61, which is connected to the gas inlet 62, passes through the interior of the charger 60, and has an opening towards the outside.

[0040] Preferably, the base 61 is shaped to correspond to the bottom surface of the housing bottom 40 of the battery pack 10. By forming it in this way, no gap is formed between the housing bottom 40 and the base 61 when the battery pack 10 is supported, and gas can be smoothly discharged from the gas inlet hole 62, which will be described next.

[0041] When the battery pack 10 is being carried, the gas inlet 62 overlaps with the outlet 41 of the battery pack 10, and introduces the gas discharged from the gas outlet path of the battery pack 10 and guides it to the outlet pipe 64.

[0042] The discharge pipe 64 discharges the gas guided from the gas inlet 62 to the outside of the charger 60. In this embodiment, an opening 66 is provided on the side of the charger 60. The opening 66 may be provided on both opposite sides of the charger 60, or it may be provided on only one side.

[0043] The pressing portion 63, used to push the sealing member 43 of the battery pack 10 upward, protrudes from the gas inlet hole 62 toward the battery pack 10 side at a position above the surface of the base 61. In this embodiment, the pressing portion 63 extends from the discharge pipe 64 through the gas inlet hole 62 and penetrates the surface of the base 61. However, the structure of the pressing portion 63 is not limited to this, and it may also be configured such that the pressing portion 63 protrudes toward the battery pack 10 side from the gas inlet hole 62.

[0044] The charger 60 has the above-described structure, thereby enabling the opening of the gas venting path of the battery pack 10 when the battery pack 10 is mounted on the charger 60, and enabling... Figure 3 The path indicated by the arrow vents the gas to the outside of the charger 60. Therefore, the generated gas will not remain in the gap between the battery pack and the charger, and there is no risk of fire.

[0045] Alternatively, the extinguishing agent 65 can be installed in the discharge pipe 64. The extinguishing agent 65 is preferably installed near the opening 66. This allows for rapid extinguishing even in the event of a gas fire, preventing the fire from spreading into the battery pack 10. Examples of the extinguishing agent 65 could be extinguishing agents composed of bicarbonates or phosphates.

[0046] Alternatively, a mesh-like flame-suppressing structure can be provided at the opening 66 in the discharge pipe 64. Preferably, the mesh structure is made of metal. By providing a mesh-like flame-suppressing structure in the discharge pipe 64, smooth gas discharge performance can be ensured, and sparks can be easily captured. If the mesh structure is used to efficiently capture sparks, the ignition suppression effect is further improved. Furthermore, in Figure 3In the discharge pipe 64, the flame extinguishing structure is provided at one opening 66, but it can also be provided at both openings 66. In addition, the flame extinguishing structure can also be provided in the discharge pipe 64, and multiple locations can be provided.

[0047] (Other application examples)

[0048] Reference Figure 4 Other application examples will be explained. Figure 4 The cross-sectional view shows the battery pack 10 installed in the electrical equipment 80, including the electrical equipment 80 and the gas venting mechanism of the battery pack 10.

[0049] When the electrical equipment 80 is in its normal state, the gas venting mechanism of the battery pack 10 is not operational. Therefore, as Figure 4 As shown, the sealing member 43 blocks the discharge hole 41, and the battery pack 10 remains in a sealed state.

[0050] Due to malfunctions in the electrical equipment 80 or the influence of ambient temperature, an abnormality may occur within the battery pack 10, causing an increase in internal pressure. In this case, it is preferable to push up the sealing member 43, which serves as a gas venting mechanism, located within the battery pack 10, thereby allowing the gas generated inside the battery pack 10 to be vented outwards.

[0051] In this case, the pressing part that pushes the sealing member 43 upward is usually housed inside the electrical device 80, and is preferably configured to be movable and exposed in case of an abnormality in the battery pack 10. There are no particular limitations on this structure.

[0052] Regarding abnormalities in battery pack 10, for example, the temperature of battery pack 10 could be measured by electrical equipment 80, and an abnormality could be detected if it exceeds a predetermined range. The temperature of battery pack 10 can be estimated by measuring the temperature of the outer surface of the casing or by measuring the temperature at other locations. Alternatively, abnormalities in battery pack 10 can also be detected by measuring its output voltage, etc.

[0053] The embodiments of this disclosure have been described above, but these embodiments are merely illustrative and do not exclude structures other than those described above. For example, in the above embodiments, the battery pack has a cuboid shape, but the appearance is not limited to this; it may also be cylindrical, or other shapes are not excluded. Furthermore, while the sides of the cuboid may be approximately the same shape, the size and shape of adjacent sides may differ. The ratio of the dimensions of the housing cover to the housing body is not limited to that shown in the accompanying drawings. Additionally, as a shape for actual use of the battery pack, protrusions, recesses, handles, terminals, etc., may sometimes be added around it, but this is done within the scope of not affecting the operation of the discharge mechanism described in this disclosure, and does not affect the function of the discharge mechanism in this embodiment.

[0054] The battery pack disclosed herein can be used as a power supply component to supply power to electronic devices. Examples include battery packs for laptops, cleaning devices, and power tools. It can also be used in batteries for electric bicycles. In addition to the examples listed here, it can also be used for other applications as a battery pack.

[0055] Furthermore, this disclosure is not limited to the above-described embodiments and their variations. Needless to say, various changes and improvements can be made within the scope of the matters described in the claims of this application.

[0056] Explanation of reference numerals in the attached figures

[0057] 10. Battery pack; 20. Housing body; 30. Housing cover; 40. Housing bottom; 41. Exhaust port; 42. Spring (force-applying component); 43. Sealing component; 44. Partition wall; 45. Vent hole; 50. Battery; 51. Retainer; 60. Charger; 61. Base; 62. Gas inlet port; 63. Pressing part; 64. Exhaust pipe; 65. Extinguishing agent; 66. Opening; 67. Connecting terminal; 70. Gas exhaust device; 80. Electrical equipment; 90. Housing.

Claims

1. An assembly composed of a battery pack and a charger for charging the battery pack, wherein the battery pack is provided with: a plurality of cells; and a case that houses the plurality of cells, the case having: an exhaust hole formed through the case; a partition wall formed in a bottomed cylindrical shape in the inside of the case so as to surround the exhaust hole; a sealing member provided in the cylinder of the partition wall and clogging the exhaust hole; and a force applying member provided in the cylinder of the partition wall and applying a force to the sealing member in the direction of the exhaust hole, the partition wall having a vent hole that forms a gas exhaust path together with the exhaust hole, the sealing member being configured to move to the inside and open the exhaust hole when pressed from the outside of the case, the charger being provided with: a base that carries the battery pack; a gas introduction hole that is a hole formed in the base and formed at a position overlapping the exhaust hole of the battery pack; an exhaust duct that is a gas passage formed in the base, communicates with the gas introduction hole, and guides gas exhausted from the battery pack to the outside of the charger; and a pressing portion that protrudes from the gas introduction hole and presses the sealing member of the battery pack, an opening portion that communicates with the exhaust duct and opens to the outside of the charger being provided in the side surface of the charger, the pressing portion pressing the sealing member and opening the exhaust hole when the charger carries the battery pack, the face of the case on which the exhaust hole is formed being in contact with the face of the charger on which the gas introduction hole is formed without a gap, and the exhaust hole and the gas introduction hole being in abutment.

2. The assembly according to claim 1, wherein a part of the partition wall of the battery pack is formed by a mesh structure and forms the vent hole.

3. The assembly according to claim 1, wherein a fire extinguishing agent is provided in the exhaust duct.

4. The assembly according to claim 1, wherein a mesh structure flame-out structure is provided in the exhaust duct. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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