Battery device having heat protection mechanism

Abstract

To provide a battery device with a heat protection mechanism that includes a plurality of cells and at least one heat dissipation container.SOLUTION: A heat dissipation container includes a frame and two films. The frame also includes at least one perforation. The film is connected to the frame and covers the perforation of the frame, thereby making the perforation a sealed space. A liquid is placed within the closed space. The liquid is water or an aqueous solution. The bottom of the cell is adjacent to the film of the heat dissipation container, a heat dissipation container film breaks when the cell temperature becomes too high. The liquid is ejected from the heat dissipation container and contacts the cell, thereby lowering the temperature of the cell.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a battery device having a heat protection mechanism that can rapidly reduce the temperature of a cell experiencing thermal runaway and effectively prevent a cell experiencing thermal runaway from causing thermal runaway in other cells. [Background technology]

[0002] Rechargeable batteries are generally a general term for batteries that can be recharged and reused, including nickel-metal hydride batteries, nickel-cadmium batteries, and lithium-ion batteries, and are widely used in electronic products, home appliances, and transportation devices.

[0003] Furthermore, with the development of industry and growing awareness of environmental protection, issues of air pollution and global warming are increasingly being given greater attention. Therefore, in order to reduce air pollution in urban areas caused by transportation, countries around the world are currently considering gradually improving relevant laws and regulations, promoting the spread and research and development of the electric vehicle industry, and banning the sale of gasoline-powered vehicles after a certain period of time.

[0004] Rechargeable batteries are one of the key technologies for the development of the electric vehicle industry, and how to increase the charge capacity of rechargeable batteries, shorten the charging time of rechargeable batteries, and improve the safety of rechargeable batteries are all key points for the popularization and development of the electric vehicle industry. Lithium-ion batteries have advantages such as high energy density, large output power, no memory effect, low self-discharge, a wide operating temperature range, and fast charge and discharge speeds, making them the rechargeable battery mainly used in electric vehicles. Summary of the Invention [Problem to be solved by the invention]

[0005] Typically, multiple cells are connected to form a battery group, and the series and / or parallel connections of the cells are adjusted to output the voltage required by the product. However, if one cell in the battery group fails and shorts out, the other healthy cells will charge the shorted cell with a large current, causing the shorted cell to abnormally rise in temperature. If the temperature exceeds the heat resistance temperature of the separator inside the cell, the separator will melt, shorting the positive and negative electrode materials of the cell, which can lead to the cell melting or exploding.

[0006] The high temperature or electrolyte leak from the failed cell can be transferred to other cells or conductive sheets, causing the temperature of the conductive sheets and connected cells to rise abnormally, potentially damaging other healthy cells and causing thermal runaway in the battery group. [Means for solving the problem]

[0007] To solve the problems faced by the prior art, the present invention provides a battery device having a heat-insulating mechanism mainly including a plurality of cells and at least one heat-dissipating container. The heat-dissipating container includes a frame and at least one film. The frame also includes a perforated portion or a recessed portion. The film is connected to the frame and covers the perforated portion or the recessed portion, thereby forming a sealed space between the frame and the film.

[0008] The bottom or positive electrode of the cell faces the film of the heat dissipation container. If the cell temperature becomes excessively high or thermal runaway occurs, for example, if the cell temperature exceeds 160 to 200 degrees Celsius, the film of the heat dissipation container breaks. A liquid is placed in the sealed space. For example, the liquid may be water or an aqueous solution. The liquid flows out through the broken film and is sprayed onto the cell whose temperature has become excessively high or which has experienced thermal runaway. This reduces the temperature of the cell and prevents a chain reaction that could cause thermal runaway in other healthy cells.

[0009] In the present invention, the liquid placed in the sealed space of the heat dissipation container is primarily water. Because water has a fairly high thermal stability and specific heat, the water or aqueous solution sprayed from the heat dissipation container can effectively reduce the temperature of a cell experiencing thermal runaway. Furthermore, the heat of vaporization of water is 40.8 kJ / mol, equivalent to 2266 kJ / kg. This is approximately 5.4 times the energy required to heat water from 0°C to 100°C. Therefore, when water is heated to its boiling point by a cell experiencing thermal runaway and evaporates from its liquid state to its gaseous state, it can absorb a larger amount of heat generated by the cell experiencing thermal runaway, thereby significantly reducing the temperature of the cell experiencing thermal runaway.

[0010] Furthermore, when the film of the heat dissipation container breaks, some of the water sprays out of the container, while some of the water remains in the heat dissipation container. The liquid or vaporized water sprayed out of the heat dissipation container directly and rapidly reduces the temperature of the cell experiencing thermal runaway. Meanwhile, the water remaining in the heat dissipation container continues to absorb the temperature of the cell experiencing thermal runaway. When the temperature of the water remaining in the heat dissipation container exceeds its boiling point, it vaporizes into water vapor, which absorbs a large amount of heat from the cell experiencing thermal runaway. This continues to reduce the temperature of the cell experiencing thermal runaway until the water remaining in the heat dissipation container is almost completely gone.

[0011] An object of the present invention is to provide a battery device having a heat protection mechanism that measures the temperature of a cell and determines whether thermal runaway has occurred in the cell without the need for a separate detector or complex control circuit. Specifically, the present invention attaches a film to a frame by adhesive or welding (e.g., brazing or soldering), forming a sealed space between the film and the frame, and water can be placed in the sealed space. Therefore, the present invention can provide a battery device having a low-cost, safe, and stable heat protection mechanism, reducing the installation cost of the battery device and achieving the objective of preventing thermal runaway in the battery device.

[0012] In addition, multiple conductive sheets can connect multiple cells in series or parallel to form a battery module. During use, such as charging and discharging, a temperature difference occurs between the two sides of the battery module. One side becomes the hot side and the other becomes the cool side. The hot and cold sides of the battery module transfer heat to the heat dissipation container via thermal conduction, creating a temperature difference between the two sides of the heat dissipation container. The temperature difference then generates convection in the liquid within the sealed space of the heat dissipation container, which can be used to balance the temperatures of the hot and cold sides of the battery module.

[0013] To achieve the above object, the present invention provides a battery device with a heat-insulating mechanism, the battery device including a plurality of cells each having two bottom surfaces and one side surface, the side surface of which is located between the two bottom surfaces, and at least one heat-dissipating container adjacent to the plurality of cells. The heat-dissipating container includes a frame including at least one perforation or recess, at least one film connected to the frame to cover the perforation or recess and form an enclosed space between the frame and the frame, the film adjacent to the bottom surface of at least one of the plurality of cells, and a liquid, which is water or an aqueous solution, disposed in the enclosed space of the heat-dissipating container.

[0014] The present invention provides a battery device with another heat-insulating mechanism. The battery device includes a plurality of cells having two bottom surfaces and one side surface, with the side surface located between the two bottom surfaces, and at least one heat-dissipating container adjacent to the plurality of cells. The heat-dissipating container includes a frame having at least one perforation, two films connected to the frame to cover the perforation and form a sealed space between the frame and the frame, the films contacting the side surfaces of the plurality of cells, and a liquid, which is water or an aqueous solution, disposed in the sealed space of the heat-dissipating container.

[0015] In the battery device with the above-mentioned heat-shielding mechanism, the frame includes a first surface, a second surface, and a side surface, and the side surface connects the first surface and the second surface. There are two films, each connected to the first surface and the second surface.

[0016] The battery device with the above-mentioned heat-insulating mechanism includes at least one connection holder connected to the frame to divide the sealed space between the frame and the film into a plurality of storage spaces.

[0017] In the battery device with the heat-insulating mechanism, the connection holder is provided with a recess or a connection hole, which connects the receiving spaces located on both sides of the connection holder.

[0018] The battery device with the above-mentioned heat-insulating mechanism includes at least one heat-conducting unit positioned between the side surfaces of adjacent cells, the heat-conducting unit facing the connection holder, and the cells facing the accommodation space.

[0019] The battery device with the above-mentioned heat-insulating mechanism includes a plurality of cells connected in series or parallel, and a plurality of conductive sheets located between the bottom surface of the cells and the film of the heat-dissipating container.

[0020] In the battery device with the above heat-insulating mechanism, the film includes at least one metal layer and at least one plastic layer.

[0021] The battery device with the above-mentioned heat-shielding mechanism includes a plurality of protrusions provided on a first surface and a second surface of the frame, with recesses between adjacent protrusions, and one film connected to the first surface and the protrusions located on the first surface, and the other film connected to the second surface and the protrusions located on the second surface.

[0022] In the battery device having the above-mentioned heat-insulating mechanism, the cells are located in the recesses of the heat-dissipating container, and the protrusions of the heat-dissipating container are located between adjacent cells. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic exploded perspective view of an embodiment of a battery device having a heat-insulating mechanism according to the present invention. [Figure 2] FIG. 2 is a schematic exploded side view of one embodiment of a battery device having a heat protection mechanism according to the present invention. [Figure 3] FIG. 3 is an exploded perspective view of an embodiment of a heat dissipation container for a battery device having a heat insulation mechanism according to the present invention. [Figure 4] FIG. 4 is a perspective view of an embodiment of a heat dissipation container of a battery device having a heat insulation mechanism according to the present invention. [Figure 5] FIG. 5 is a schematic exploded perspective view of another embodiment of a battery device having a heat-insulating mechanism according to the present invention. [Figure 6] FIG. 6 is a schematic exploded perspective view of an embodiment of a heat dissipation container for a battery device having a heat-insulating mechanism according to the present invention. [Figure 7] FIG. 7 is a schematic exploded perspective view of another embodiment of a heat dissipation container for a battery device having a heat-insulating mechanism according to the present invention. [Figure 8] FIG. 8 is a schematic exploded perspective view of another embodiment of a heat dissipation container for a battery device having a heat-insulating mechanism according to the present invention. [Figure 9] FIG. 9 is a schematic exploded perspective view of another embodiment of a battery device having a heat-insulating mechanism according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Please refer to Figures 1 and 2, which are a schematic exploded perspective view and a schematic exploded side view, respectively, of an embodiment of a battery device having a heat protection mechanism according to the present invention. Also, Figures 3 and 4 are an exploded perspective view and a three-dimensional perspective view, respectively, of an embodiment of a heat dissipation container of a battery device having a heat protection mechanism according to the present invention. As shown in the figures, a battery device 10 having a heat protection mechanism mainly includes at least one heat dissipation container 11 and a plurality of cells 13. The heat dissipation container 11 is adjacent to the cells 13, for example, located at both ends of the cells 13.

[0025] 3 and 4, the heat dissipation container 11 includes a frame 111 and two films 113. The frame 111 also includes a perforated portion 112. The two films 113 are respectively installed on two surfaces of the frame 111 and cover the perforated portion 112 of the frame 111, thereby forming an airtight space 114 between the frame 111 and the films 113.

[0026] A liquid 15 is placed in the sealed space 114. The liquid 15 may be water or an aqueous solution. In one embodiment of the present invention, the liquid 15 occupies only a portion of the sealed space 114, and the liquid 15 is not placed in the rest of the sealed space 114. The liquid 15 is flowable within the sealed space 114 and is located at the bottom of the sealed space 114 due to the action of gravity. Therefore, gas or water vapor may be present in the sealed space 114 where the liquid 15 is placed. In another embodiment, the sealed space 114 may be filled with the liquid 15.

[0027] Specifically, the frame 111 may include a first surface 1111, a second surface 1113, and a side surface 1115. The side surface 1115 connects the first surface 1111 and the second surface 1113. Two films 113 are connected to the first surface 1111 and the second surface 1113 of the frame 111, respectively. For example, the films 113 may be attached to the first surface 1111 and the second surface 1113 of the rectangular frame 111 by adhesive, welding, or soldering to form the rectangular parallelepiped heat dissipation container 11. In another embodiment, the film 113 may be a tape that is attached to the first surface 1111, the second surface 1113, and the side surface 1115 of the frame 111.

[0028] In another embodiment of the present invention, the perforated portion 112 of the frame 111 may be a recessed portion, and the recessed portion of the frame 111 may be covered with one film 113 to form an enclosed space 114 in the recessed portion. The frame 111 may be made of a metal material with high thermal conductivity, such as aluminum or copper. The frame 111 may also be connected to the cell 13 via the film 113. This allows the cell 13 to transfer heat to the frame 111 and the liquid 15, thereby conveniently lowering the temperature of the cell 13.

[0029] 2, the cell 13 includes two bottom surfaces 131 and one side surface 133. The side surface 133 is located between the two bottom surfaces 131. This gives the cell 13 an external appearance that is approximately columnar, such as a cylindrical body. One bottom surface 131 of the cell 13 may be used as a positive electrode, and the other bottom surface 131 and / or side surface 133 may be used as a negative electrode.

[0030] A plurality of conductive sheets 12 are used to connect a plurality of cells 13 in series and / or parallel to form a battery module 130. In one embodiment of the present invention, the number of heat dissipation containers 11 may be two, each adjacent to two bottom surfaces 131 of the cells 13. In another embodiment of the present invention, the number of heat dissipation containers 11 may be one, adjacent to one bottom surface 131 of the cells 13.

[0031] Specifically, the film 113 of the heat dissipation container 11 is adjacent to at least one bottom surface 131 of the cell 13. Alternatively, a conductive sheet 12 is provided between the bottom surface 131 of the cell 13 and the film 113 of the heat dissipation container 11. For example, the positive electrode and / or negative electrode of the cell 13 may be in direct contact with the film 113 of the heat dissipation container 11, or may be in contact with the film 113 of the heat dissipation container 11 via the conductive sheet 12. When thermal runaway occurs in the cell 13, high-temperature gas typically escapes from the cell 13 through a valve on the bottom surface 131 (e.g., the positive electrode) and comes into contact with the film 113 of the heat dissipation container 11.

[0032] The film 113 breaks when it comes into contact with the high-temperature gas, causing the liquid 15 located in the sealed space 114 of the heat-dissipating container 11 to spurt or flow out of the heat-dissipating container 11 through the ruptured hole in the film 113. The liquid 15 spurting out of the heat-dissipating container 11 comes into contact with the cells 13 experiencing thermal runaway, and reduces the temperature of the cells 13 experiencing thermal runaway.

[0033] In one embodiment of the present invention, a water-absorbing layer, such as a porous metal or porous ceramic, is provided in the sealed space 114, and the water-absorbing layer absorbs the liquid 15. When the film 113 is torn, some of the liquid 15 will spurt out or flow out of the heat-dissipating container 11 through the torn hole in the film 113 and come into direct contact with the cells 13 experiencing thermal runaway, while some of the liquid 15 will be absorbed by the water-absorbing layer.

[0034] The liquid 15 adsorbed by the water absorption layer continues to absorb heat from the cells 13 experiencing thermal runaway, and changes from liquid to gaseous state, thereby absorbing a large amount of heat from the cells 13 experiencing thermal runaway. Since the heat of vaporization of water is 40.8 kJ / mol, which corresponds to 2266 kJ / kg, it is possible to absorb a large amount of heat from the cells 13 experiencing thermal runaway when the water is converted into steam. Therefore, in the present invention, the liquid 15 placed in the heat dissipation container 11 is preferably water or an aqueous solution.

[0035] Generally, the temperature generated by the cells 13 during thermal runaway is between 160 and 240 degrees Celsius. Therefore, in one embodiment of the present invention, the thickness, material, and other variables of the film 113 may be adjusted so that the film 113 breaks between 160 and 240 degrees Celsius. In one embodiment of the present invention, the film 113 may be a metal film or a plastic film. The metal film may include a laminate of at least one metal layer and at least one plastic layer, such as a laminate of aluminum foil and polyethylene. Furthermore, the film 113 and the frame 111 may be connected by hot welding.

[0036] In addition, when the battery module 130 includes multiple cells 13 connected in series, a temperature difference occurs between the cells 13 on both sides of the battery module 130 during charging and discharging. In the case of Figure 2, the temperature of the cell 13 located on the left side is lower than the temperature of the cell 13 located on the right side, and after multiple charging and discharging cycles, the degradation rate of the cell 13 on the right side is faster than that of the cell 13 on the left side.

[0037] In the embodiment of the present invention, the high-temperature cells 13 can not only transfer heat to the low-temperature cells 13 through the frame 111, but also transfer heat to the liquid 15 in the sealed space 114 through the frame 111 and / or the film 113. Specifically, the temperature of the liquid 15 on the right side of the sealed space 114 is higher than the temperature of the liquid 15 on the left side. This causes convection in the liquid 15 in the sealed space 114, which balances the temperatures of the cells 13 and extends the service life of the battery module 130.

[0038] 5, the frame 111 of the heat dissipation container 11 may include at least one connection holder 1117. The connection holder 1117 is located in the perforated portion 112 or recessed portion of the frame 111 to divide the sealed space 114 between the frame 111 and the film 113 into multiple accommodation spaces 118. The film 113 is connected to the frame 111 and the connection holder 1117.

[0039] In one embodiment of the present invention, the cells 13 are arranged in a matrix. A heat conduction unit 17 can be installed between the side surfaces 133 of adjacent cells 13. The heat conduction unit 17 faces the connection holder 1117, and the cells 13 face the receiving space 118. For example, the heat conduction unit 17 can be a circular, square, or polygonal metal pillar. One or both ends of the heat conduction unit 17 can be connected to the connection holder 1117 of the frame 111 via the film 113. Heat generated in the cells 13 can be transferred to the heat conduction unit 17 through the side surfaces 133 and then transferred to the connection holder 1117 of the frame 111 through one or both ends of the heat conduction unit 17.

[0040] As shown in FIG. 6, at least one recess 1119 or connection hole may be provided in the connection holder 1117 of the frame 111, and the receiving spaces 118 located on both sides of the connection holder 1117 may be connected by the recess 1119 or connection hole.

[0041] As shown in FIG. 7, the frame 111 may include a plurality of protrusions 115, with recesses 116 formed between adjacent protrusions 115. In one embodiment of the present invention, the protrusions 115 may be provided on both the first surface 1111 and the second surface 1113 of the frame 111. The protrusions 115 provided on the first surface 1111 and the protrusions 115 provided on the second surface 1113 may be staggered. Furthermore, as shown in FIG. 8, the protrusions 115 provided on both sides of the frame 111 may straddle the perforated portion 112 in the frame 111, forming rod-shaped protrusions 115 on both sides of the perforated portion 112.

[0042] The two films 113 are connected to the first surface 1111 and the second surface 1113 of the frame 111, respectively, and cover the perforated portions 112, thereby forming a sealed space 114 between the two films 113 and the frame 111. In actual application, one film 113 is connected to the first surface 1111 and the protrusions 115 located on the first surface 1111, and the other film 113 is connected to the second surface 1113 and the protrusions 115 located on the second surface 1113.

[0043] In the above-described embodiment of the present invention, the heat-dissipating container 11 is mainly installed on the bottom surface 131 of the cell 13, and the film 113 of the heat-dissipating container 11 is adjacent to the bottom surface 131 of the cell 13. In another embodiment of the present invention, as shown in FIG. 9 , the heat-dissipating container 11 may be installed between two adjacent cells 13. In this case, the film 113 of the heat-dissipating container 11 can contact the side surfaces 133 of multiple cells 13. Alternatively, the cells 13 may be placed in the recessed portions 116 of the heat-dissipating container 11. As a result, the side surfaces 133 of the cells 13 are positioned within the recessed portions 116, and the protruding portions 115 of the heat-dissipating container 11 are positioned between the two adjacent cells 13. This increases the contact area between the side surfaces 133 of the cells 13 and the heat-dissipating container 11, which is advantageous for improving the efficiency of heat transfer from the cells 13 to the heat-dissipating container 11.

[0044] In actual applications, a battery module 130 may include multiple cells 13 and multiple heat dissipation containers 11. The heat dissipation containers 11 fill the gaps between adjacent cells 13 as much as possible, and allow the side surfaces 133 of each cell 13 to contact at least one heat dissipation container 11, thereby improving the heat dissipation effect.

[0045] The above is merely a preferred embodiment of the present invention and does not limit the scope of the present invention. That is, any equivalent modifications and additions based on the shape, structure, features and spirit described in the claims of the present invention are all intended to be included in the claims of the present invention. [Explanation of symbols]

[0046] 10 Battery device with heat protection mechanism 11 Heat dissipation container 111 frames 1111 First Side 1113 Second Side 1115 Side 1117 Connection holder 1119 recess 112 Perforation part 113 Film 114 Closed space 115 Protrusion 116 Depression 118 Containment Space 12 Conductive sheet 13 cells 130 Battery Module 131 bottom 133 Side 15 liquid 17 Heat conduction unit

Claims

1. In a battery device having a heat protection mechanism, a plurality of cells each including two bottom surfaces and one side surface, the side surface being located between the two bottom surfaces; and at least one heat dissipation container adjacent to the plurality of cells, the heat dissipation container comprising: a frame including at least one perforation; two films connected to the frame to cover the perforated portions and form a sealed space between the frame and the two films in contact with the side surfaces of the plurality of cells; and a liquid disposed in the sealed space of the heat dissipation container, the liquid being water or an aqueous solution; the frame includes a first surface and a second surface; the frame includes a plurality of protrusions disposed on the first surface and the second surface, a recess exists between adjacent protrusions, one of the films is connected to the first surface and the protrusions located on the first surface, and the other of the films is connected to the second surface and the protrusions located on the second surface; A battery device in which the cells are located within recesses in the heat dissipation container, and the protrusions of the heat dissipation container are located between adjacent cells.

2. The battery device with a heat-insulating mechanism according to claim 1 , wherein the frame includes a side surface, the side surface connecting the first surface and the second surface.

3. 10. The battery device with a heat-insulating mechanism of claim 1, wherein the film includes at least one metal layer and at least one plastic layer.

Images