High-capacity battery and electric equipment

Abstract

The utility model provides a high-capacity battery and electric equipment. The high-capacity battery comprises a gas sharing chamber and a plurality of single batteries, the gas areas of the inner cavities of the plurality of single batteries are communicated with the gas sharing chamber, and the gas sharing chamber is provided with a one-way gas-permeable membrane for discharging gas out of the gas sharing chamber in a one-way manner. According to the high-capacity battery disclosed by the utility model, the gas areas of the single batteries are communicated through the gas sharing chamber, so that gas generated by each single battery is discharged to the gas sharing chamber, and gas generated in the high-capacity battery can be continuously discharged through the one-way gas-permeable membrane arranged on the gas sharing chamber; and the problem that the performance is influenced and even thermal runaway occurs due to overhigh air pressure of a high-capacity battery is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the field of batteries, in particular to a large-capacity battery and electrical equipment. Background Art

[0002] With the further development of lithium-ion batteries in recent years, the application scenarios of lithium-ion batteries have become more and more extensive, especially some use scenarios that require relatively large battery capacity. For example: automotive power batteries, energy storage batteries that constitute household photovoltaic and energy storage integrated devices, and batteries that constitute energy storage systems for power plants.

[0003] In the above usage scenarios, in order to meet the larger capacity requirements, the existing practice is to connect multiple single cells in series and parallel to form a large-capacity battery. However, due to the differences between the single cells in the above large-capacity battery, the uniformity of the single cells in the large-capacity battery is poor, which directly leads to the limitation of the capacity and cycle life of the large-capacity battery.

[0004] Among them, since each single cell of a large-capacity battery in the related technology will generate gas after running for a period of time, excessive gas pressure in the single cell will affect the performance of the large-capacity battery, and in severe cases will cause thermal runaway of the large-capacity battery. Utility Model Content

[0005] In order to solve the problem that the performance of a large-capacity battery is affected or even thermal runaway occurs due to excessive gas pressure in a single cell, the first aspect of the utility model provides a large-capacity battery.

[0006] The large-capacity battery comprises a gas-sharing chamber and a plurality of single cells; the gas areas in the inner cavities of the plurality of single cells are connected to the gas-sharing chamber, and a one-way air-permeable membrane is provided on the gas-sharing chamber for unidirectionally discharging gas from the gas-sharing chamber.

[0007] The gas areas of the monomer cells in the large-capacity battery of the utility model are connected through a gas sharing chamber, so that the gas generated by each monomer cell is discharged into the gas sharing chamber, and the gas generated in the large-capacity battery can be continuously discharged through the one-way air permeable membrane arranged on the gas sharing chamber, which greatly reduces the problem of excessive gas pressure in the large-capacity battery affecting performance or even causing thermal runaway.

[0008] The one-way breathable membrane can also prevent the gas from the external environment from entering the large-capacity battery and causing contamination to the large-capacity battery.

[0009] In some special usage scenarios, once a large-capacity battery experiences thermal runaway, the one-way breathable membrane can also serve as an explosion relief mechanism. There is no need to add an additional explosion relief mechanism to the large-capacity battery, thus simplifying the structure of the large-capacity battery.

[0010] Furthermore, the above-mentioned gas sharing chamber is a first hollow tube; air holes are opened on the single battery shell; a plurality of first through holes are opened on the first hollow tube, the first hollow tube is connected to each single battery shell, and the plurality of first through holes of the first hollow tube corresponds one by one to the air holes on each single battery, so that the gas areas in each single battery are connected; and the one-way air permeable membrane is arranged on the first hollow tube.

[0011] Furthermore, the large-capacity battery further comprises a second hollow tube; a plurality of second through holes are formed on the second hollow tube, and a liquid hole is formed on the single battery shell; the second hollow tube is connected to each single battery shell, and the plurality of second through holes of the second hollow tube correspond to the liquid holes on each single battery one by one, so that the electrolyte areas in each single battery are connected;

[0012] The positive terminals of all the single cells are connected as a total positive electrode, and the negative terminals of all the single cells are connected as a total negative electrode.

[0013] Furthermore, the total positive electrode and the total negative electrode are provided with heat exchange tubes for exchanging heat with an external temperature control device.

[0014] Furthermore, the large-capacity battery further comprises a box, wherein a plurality of single cells are placed side by side in the box, and avoidance holes are provided on the top plate of the box corresponding to the polarity terminals of each single cell; the polarity terminals of each single cell extend out of the avoidance holes, and the top plate area of ​​the box corresponding to the avoidance holes is fixedly sealed with the shell of the single cell;

[0015] The positive terminals of all single cells are connected as the total positive electrode, and the negative terminals of all single cells are connected as the total negative electrode;

[0016] The box body is provided with a first channel as the gas sharing chamber; the single battery shell is provided with air holes; the first channel is connected with the gas area in the single battery through the air holes; and the one-way air permeable membrane is provided on the first channel.

[0017] Furthermore, the above-mentioned large-capacity battery also includes a second channel arranged on the box body; a liquid hole is opened on the single cell shell; and the second channel is connected with the electrolyte area in each single cell through the liquid hole on the single cell.

[0018] Furthermore, the positive terminals of all the batteries are connected as a total positive electrode, and the negative terminals of all the battery cells are connected as a total negative electrode.

[0019] Furthermore, the total positive electrode and the total negative electrode are provided with heat exchange tubes for exchanging heat with an external temperature control device.

[0020] The second aspect of the utility model provides an electrical device, comprising a gas processing device, a smoke pipe assembly, and at least one large-capacity battery as described in the first aspect;

[0021] The smoke pipe assembly connects the gas processing device and the large-capacity battery, and a one-way air-permeable membrane is provided at the position where the smoke pipe assembly is connected to the large-capacity battery; the gas processing device is used to continuously process the gas discharged from the one-way air-permeable membrane.

[0022] Furthermore, the gas processing device includes at least one of an adsorption tank, a gas collection tank and an ignition device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the large-capacity battery structure of Example 1;

[0024] Figure 2 This is a schematic diagram of the large-capacity battery structure of Example 2;

[0025] Figure 3 The structure of the large-capacity battery in Example 3 is shown in FIG. Figure 1 ;

[0026] Figure 4 The structure of the large-capacity battery in Example 3 is shown in FIG. Figure 1 ;

[0027] Figure 5 This is the schematic diagram of the electrical equipment.

[0028] The reference numerals are as follows:

[0029] 100-monocell, 200-first hollow tube, 300-one-way breathable membrane, 400-second hollow tube, 500-box, 600-gas sharing chamber, 700-electrolyte sharing chamber, 800-heat exchange tube;

[0030] 1-large capacity battery, 2-smoke pipe assembly, 21-main manifold, 22-branch pipe, 3-gas processing device, 31-adsorption tank, 32-ignition device, 33-gas collection tank. DETAILED DESCRIPTION

[0031] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments. Obviously, the described embodiments are only part of the embodiments, not all of the embodiments. Based on the following embodiments, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this utility model.

[0032] At the same time, it should be noted that the orientations or positional relationships indicated by the terms "top, bottom, inside and outside" in the text are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the technical solution. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] In this utility model, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0034] The basic design idea of ​​the utility model is: the large-capacity battery includes a gas-sharing chamber and multiple single cells; the gas areas of the inner cavities of the multiple single cells are connected to the gas-sharing chamber, and the gas-sharing chamber is provided with a one-way air-permeable membrane for unidirectionally discharging the gas from the gas-sharing chamber. In the large-capacity battery of the utility model, the gas areas of each single cell are connected through the gas-sharing chamber, so that the gas generated by each single cell is discharged to the gas-sharing chamber, and the gas generated in the large-capacity battery can be continuously discharged through the one-way air-permeable membrane provided on the gas-sharing chamber, which greatly reduces the problem of excessive gas pressure in each single cell affecting the performance of the large-capacity battery or even causing thermal runaway.

[0035] At the same time, the one-way breathable membrane can also prevent the gas from the external environment from entering the large-capacity battery and causing pollution to the large-capacity battery.

[0036] In some special usage scenarios, once a large-capacity battery experiences thermal runaway, the one-way breathable membrane can also serve as an explosion relief mechanism. There is no need to add an additional explosion relief mechanism to the large-capacity battery, thus simplifying the structure of the large-capacity battery.

[0037] Example 1

[0038] like Figure 1 As shown, the large-capacity battery includes a plurality of single cells 100 and a first hollow tube 200; the plurality of single cells 100 are placed side by side to form a battery pack body;

[0039] The first hollow tube 200 is used as a gas sharing chamber; the shell of the single battery is provided with air holes; the first hollow tube is provided with a plurality of first through holes, the first hollow tube is connected to the shells of each single battery, and the plurality of first through holes of the first hollow tube corresponds to the air holes on each single battery, so that the gas areas in each single battery are connected; the one-way air permeable membrane 300 is arranged on the first hollow tube 200. In this embodiment, the air holes are arranged on the top of the shell of the single battery, and the first hollow tube is located above the large-capacity battery. The first hollow tube 200 is in the form of a tube with a circular or rectangular cross section; the one-way air permeable membrane 300 is arranged at the port at either end of the first hollow tube 200.

[0040] In some other embodiments, the first hollow tube 200 can also be formed by extruding and splicing sub-pipes arranged on the single battery housing. In addition, the air hole can also be arranged on the side wall of the single battery housing near the top of the housing, and the first hollow tube 200 is located on the side of the large-capacity battery.

[0041] The battery pack body may be composed of a plurality of single cells 100 connected in series or in parallel.

[0042] Example 2

[0043] like Figure 2 As shown, the large-capacity battery of this embodiment is based on the embodiment 1, and a second hollow tube 400 is added, and multiple single cells 100 are arranged in parallel to form a battery pack body (specifically, the positive terminals of all single cells 100 are connected as the total positive electrode, and the negative terminals of all single cells are connected as the total negative electrode); a liquid hole is opened on the shell of the single cell 100; a plurality of second through holes are opened on the second hollow tube 400, and the second hollow tube 400 is connected to the shell of each single cell, and the plurality of second through holes of the second hollow tube 400 correspond one by one to the liquid holes on each single cell, so that the electrolyte area in each single cell is connected.

[0044] In this embodiment, the liquid hole is arranged at the bottom of the single battery housing, and the second hollow tube 400 is located below the large-capacity battery. The shape of the second hollow tube 400 is basically the same as that of the first hollow tube 200;

[0045] In some other embodiments, the liquid hole may also be disposed on the side wall of the single cell housing close to the bottom of the housing, and the second hollow tube 400 is located on the side of the large-capacity battery.

[0046] Example 3

[0047] like Figure 3 and Figure 4As shown, the large-capacity battery of this embodiment further includes a box body 500 and a plurality of single cells 100; the plurality of single cells 100 are placed side by side in the box body 500, and the electrolyte areas of the single cells are interconnected; a pole avoidance hole is provided on the top plate of the box body 500 corresponding to the polarity terminal of each single cell; the polarity terminal of each single cell extends out of the pole avoidance hole, and the top plate area of ​​the box body 500 corresponding to the pole avoidance hole is fixedly sealed with the shell of the single cell 100;

[0048] The positive terminals of all the single cells 100 are connected as a total positive electrode, and the negative terminals of all the single cells 100 are connected as a total negative electrode.

[0049] The box body 500 is provided with a gas sharing chamber 600 extending along the arrangement direction of the single cells 100; the single cell shell is provided with air holes; the gas sharing chamber 600 is connected with the gas area in the single cell through the air holes; and the one-way air permeable membrane 300 is provided on the gas sharing chamber 600.

[0050] In order to ensure that the electrolyte areas of each single cell are connected and the continuity of the liquid level is good (to avoid liquid interruption), and at the same time ensure that there is a sufficient amount of electrolyte in the large-capacity battery, the large-capacity battery of this embodiment also includes an electrolyte sharing chamber 700 arranged on the box body 500 and extending along the arrangement direction of the single cells; the electrolyte sharing chamber 700 is connected to the electrolyte areas of each single cell.

[0051] In some other embodiments, the internal space of the box 500 may be directly used as the electrolyte sharing chamber. However, in this case, the electrolyte sharing system may have a discontinuous liquid level.

[0052] Among them, the shape of the box has the following forms:

[0053] 1. The box body 500 includes a cylinder, a first cover plate, and a second cover plate; the top and bottom of the cylinder are both open, the first cover plate is sealed and fixed (welded) to the top of the cylinder, and the second cover plate is sealed and fixed (welded) to the bottom of the cylinder;

[0054] The first cover plate is provided with a pole avoidance hole for the extension of the polarity terminals of multiple single cells, and the first cover plate is integrally formed with a groove body protruding upward, which serves as a gas sharing chamber; the second cover plate is integrally formed with a groove serving as an electrolyte sharing chamber.

[0055] 2. The box body 500 includes a U-shaped shell, a first cover plate, a third cover plate and a fourth cover plate; the top, front and rear of the U-shaped shell are all open, the first cover plate is sealed and fixed (welded) to the top of the U-shaped shell, and the third cover plate and the fourth cover plate are sealed and fixed (welded) to the front and rear of the U-shaped shell respectively.

[0056] The first cover plate is provided with 2N pole avoidance holes for the extension of the polarity terminals of multiple single cells. The first cover plate is integrally formed with an upwardly protruding groove body, which serves as a gas sharing chamber; a groove is integrally formed on the bottom of the U-shaped shell as an electrolyte sharing chamber.

[0057] 3. The box body 500 includes a cylinder, a third cover plate, and a fourth cover plate; the front and rear of the cylinder are open, the third cover plate is sealed and fixed (welded) to the front of the cylinder, and the fourth cover plate is sealed and fixed (welded) to the rear of the cylinder;

[0058] The top of the cylinder is provided with a plurality of pole avoidance holes for the extension of the polarity terminals of a plurality of single cells. The top of the cylinder is integrally formed with a groove body protruding upward, which serves as a gas sharing chamber; the bottom of the cylinder is integrally formed with a groove as an electrolyte sharing chamber.

[0059] In the above three types of shells, the cylinder and the U-shaped shell can be spliced ​​by welding, or can be integrally formed by casting or stamping. In order to facilitate processing and ensure sealing, the integral forming method is usually selected.

[0060] In order to ensure the sealing of the box, the box area corresponding to the pole avoidance hole needs to be fixedly sealed with the single battery shell; the fixed sealing at this location can be achieved in the following three ways:

[0061] Method 1: The edge of the pole avoidance hole can be welded to the top cover of the single battery to achieve sealing;

[0062] However, if the height dimensions of each single battery are not completely equal, some single battery covers with smaller height dimensions may have problems with poor welding or even be unable to be welded to the top of the box body. In this case, the following method 2 or method 3 can be used.

[0063] Method 2: A weak portion is provided in the peripheral area of ​​the pole avoidance hole. During the welding process, the size difference of the top covers of each single battery in the height direction is compensated by the deformation of the weak portion, so that the polarity terminals of all single batteries extend out of the pole avoidance hole. The weak portion in this embodiment can be an annular groove with the center of the pole avoidance hole as the center point and opened along the peripheral area of ​​the pole avoidance hole. In other embodiments, the weak portion can also be a long strip groove opened in the peripheral area of ​​the pole avoidance hole. In other embodiments, if there is a similar problem, that is, the polarity terminals of all single batteries cannot be fully extended out of the pole avoidance hole at the same time, the solution can be adopted to add a weak portion in the peripheral area of ​​the pole avoidance hole.

[0064] Method 3: Add a hollow connector between the pole avoidance hole and the polarity terminal; the bottom of the hollow connector is used to be sealed and connected to the first area of ​​the single cell, and the top of the hollow connector is sealed and connected to the second area of ​​the box; the first area is the area around any polarity terminal in the top cover of any single cell; the second area is the area corresponding to any pole avoidance hole on the box. The area corresponding to the pole avoidance hole is the surrounding area on the outer surface of the box corresponding to any pole avoidance hole; or the area corresponding to the pole avoidance hole is the wall of the pole avoidance hole. Among them, the area around the pole avoidance hole is the area around the insulating sealing pad on the pole avoidance hole. The insulating sealing pad is a part on the single cell used to insulate the pole avoidance hole and the top cover.

[0065] The large-capacity batteries in the above embodiments 1 to 3 are provided with heat exchange tubes 800 ; the heat exchange tubes 800 are matched with the mounting parts of the polarity terminals of each single battery.

[0066] The heat exchange tube 800 can be specifically provided in the following ways:

[0067] 1. An aluminum tube is bent into a U-shaped structure, and two parallel tube sections are used to cooperate with the total positive electrode and the total negative electrode respectively, so as to realize the heat exchange between each single battery and the external temperature control device, and the liquid inlet and liquid outlet of the aluminum tube are located on the same side; the transmission medium in the aluminum tube can be water, insulating oil or fluorinated liquid; or two aluminum tubes can be used to cooperate with the total positive electrode and the total negative electrode respectively.

[0068] 2. Two cored heat pipes are used to cooperate with the total positive electrode and the total negative electrode respectively, so as to realize the heat exchange between each single battery and the external temperature control device. The cored heat pipe is an evaporation-condensation type heat exchange equipment, which realizes heat transmission by the state change of the working fluid in the pipe.

[0069] Since the heat transfer effect of the cored heat pipe is affected by the length of the cored heat pipe, when the number of single cells in a large-capacity battery is large (i.e., the length of the large-capacity battery is long), the use of the cored heat pipe will be limited. Therefore, in this embodiment, aluminum tubes are preferably selected as heat exchange tubes. If the insulation between the heat exchange tubes and the polarity terminals can be effectively ensured, water can be preferably used as the heat transfer medium flowing in the aluminum tube from the aspects of heat transfer efficiency and cost.

[0070] Example 4

[0071] This embodiment provides an electrical device, such as Figure 5 As shown, the electrical equipment includes a gas processing device 3, a smoke pipe assembly 2 and at least one large-capacity battery 1 as described in embodiments 1 to 3;

[0072] The smoke tube assembly 2 connects the gas processing device 3 and the large-capacity battery 1, and a one-way air-permeable membrane 300 is provided at the position where the smoke tube assembly 2 and the large-capacity battery 1 are connected; the gas processing device 3 is used to continuously process the gas discharged from the one-way air-permeable membrane 300.

[0073] The electrical equipment is an electric vehicle or an energy storage device;

[0074] When the number of the large-capacity battery 1 is one, the smoke pipe assembly 2 is a smoke pipe, one end of which is connected to the gas processing device, and the other end is connected to the position where the one-way air permeable membrane is provided in the large-capacity battery;

[0075] When there are multiple large-capacity batteries 1, the smoke pipe assembly 2 includes a main manifold 21 and multiple branch pipes 22. One end of the branch pipe 22 is connected to the main manifold 21, and the other end is connected to the position where the one-way air permeable membrane is provided on the large-capacity battery 1. The main manifold 21 is used to transport the gas exhausted by multiple large-capacity batteries to the gas treatment device 3 for continuous treatment, so as to avoid the exhaust gas from polluting the external environment.

[0076] The gas processing device 3 includes at least one of an adsorption tank 31, a gas collection tank 33 and an ignition device 32. Specifically, the gas processing device can be a gas collection tank 33 for collecting gas separately, an adsorption tank 31 for adsorbing gas, or an ignition device 32 for igniting gas.

[0077] In order to more thoroughly treat the gas discharged during the operation of large-capacity batteries, or in some extreme cases, when thermal runaway occurs in large-capacity batteries, the one-way air permeable membrane on the gas sharing chamber is broken, and the amount of thermal runaway flue gas is large. In order to thoroughly treat the thermal runaway flue gas, the gas treatment device can be an adsorption tank 31 and an ignition device 32 arranged in sequence along the gas discharge direction, or an adsorption tank 31, an ignition device 32 and a gas collection tank 33 arranged in sequence along the gas discharge direction.

Claims

1. A large capacity battery, characterized in that: It includes a gas sharing chamber and a plurality of single cells; The gas areas of the inner cavities of the plurality of single cells are connected to the gas sharing chamber, and the gas sharing chamber is provided with a one-way air permeable membrane for unidirectionally discharging gas from the gas sharing chamber.

2. The large-capacity battery according to claim 1, characterized in that: The gas sharing chamber is a first hollow tube; air holes are provided on the single cell shell; a plurality of first through holes are provided on the first hollow tube, the first hollow tube is connected to each single cell shell, the plurality of first through holes of the first hollow tube corresponds one by one to the air holes on each single cell, so that the gas areas in each single cell are connected; a one-way air permeable membrane is arranged on the first hollow tube.

3. The large-capacity battery according to claim 2, characterized in that: It also includes a second hollow tube; a liquid hole is opened on the single battery shell; a plurality of second through holes are opened on the second hollow tube, the second hollow tube is connected to each single battery shell, and the plurality of second through holes of the second hollow tube correspond to the liquid holes on each single battery, so that the electrolyte area in each single battery is connected; The positive terminals of all the single cells are connected as a total positive electrode, and the negative terminals of all the single cells are connected as a total negative electrode.

4. The large-capacity battery according to claim 3, characterized in that: The total positive electrode and the total negative electrode are provided with heat exchange tubes for exchanging heat with an external temperature control device.

5. The large-capacity battery according to claim 1, characterized in that: The box also includes a box body, in which a plurality of single cells are placed side by side, and the electrolyte areas of the single cells are interconnected; a avoidance hole is provided on the top plate of the box body corresponding to the polarity terminal of each single cell; the polarity terminal of each single cell extends out of the avoidance hole, and the top plate area of ​​the box body corresponding to the avoidance hole is fixedly sealed with the shell of the single cell; The positive terminals of all single cells are connected as the total positive electrode, and the negative terminals of all single cells are connected as the total negative electrode; The box body is provided with a gas sharing chamber extending along the arrangement direction of the single cells; the single cell shell is provided with air holes; the gas sharing chamber is connected with the gas area in the single cell through the air holes; and the one-way air permeable membrane is provided on the gas sharing chamber.

6. The large-capacity battery according to claim 5, characterized in that: The box body is provided with an electrolyte sharing chamber extending along the arrangement direction of the single cells; the single cell shell is provided with liquid holes; the electrolyte sharing chamber is connected with the electrolyte area in each single cell through the liquid holes on the single cell.

7. The large-capacity battery according to claim 6, characterized in that: Heat exchange tubes are installed on the total positive electrode and the total negative electrode.

8. An electrical device, characterized in that: comprising a gas processing device, a smoke pipe assembly and at least one large-capacity battery as claimed in any one of claims 1 to 7; The smoke pipe assembly connects the gas processing device and the large-capacity battery, and a one-way air-permeable membrane is provided at the position where the smoke pipe assembly is connected to the large-capacity battery; the gas processing device is used to continuously process the gas discharged from the one-way air-permeable membrane.

9. An electrical equipment according to claim 8, characterized in that: The gas processing device includes at least one of an adsorption tank, a gas collection tank and an ignition device.

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