Battery module and method for controlling the battery module

Abstract

A battery module according to an embodiment of the present invention may include a housing, a plurality of secondary batteries built into the housing, a fluid provided inside the housing so that the plurality of secondary batteries are immersed, and a pressurizing unit provided to apply pressure to the fluid.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0030734 filed March 8, 2023 and Korean Patent Application No. 10-2024-0015062 filed January 31, 2024, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to a battery module and a method for controlling the battery module. [Background technology]

[0003] In order to solve the problems of environmental pollution and the energy source problem caused by the depletion of petroleum resources, research and development into power generation based on environmentally friendly energy sources is being conducted. In particular, research into secondary batteries is being actively conducted, and various aspects of secondary battery materials, structures, processes, and stability are being studied.

[0004] Multiple secondary batteries may be installed and managed as a module or pack, and undergo repeated charge and discharge processes. To improve energy density, the voltage applied to secondary batteries is increasing, and development is underway to reduce gas generation through electrolyte additives and surface modification of cathode materials. Furthermore, there is a need to structurally suppress gas generation to improve the swelling phenomenon of secondary batteries and enhance the stability of modules or packs.

[0005] According to conventional technology, when a swelling phenomenon occurs due to gas generation in a plurality of secondary batteries, it is difficult to structurally control the swelling, which may cause stability problems. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide a battery module and a method for controlling the battery module that can suppress swelling and improve structural stability. [Means for solving the problem]

[0007] A battery module according to an embodiment of the present invention may include a housing, a plurality of secondary batteries housed in the housing, a fluid disposed inside the housing to immerse the plurality of secondary batteries, and a pressurizing unit disposed to apply pressure to the fluid.

[0008] The pressurizing portion may be disposed on the housing so as to be movable relative to the fluid.

[0009] The fluid may include an incompressible fluid.

[0010] The battery module may further include a pressure sensor configured to sense a change in pressure of the fluid.

[0011] The pressure sensor may be mounted on the housing such that one end is in contact with the fluid for sensing pressure changes in the fluid.

[0012] The pressurizing unit may be configured to pressurize the fluid based on a detection result of the pressure sensor.

[0013] The pressurizing unit may be configured to pressurize the fluid with a pressure that is equal to or exceeds the degree of pressure increase of the fluid sensed by the pressure sensor.

[0014] The fluid may be a fire-retardant fluid.

[0015] The fluid may also be silicone oil.

[0016] The battery module may further include a fluid inlet provided on one side of the housing; and a fluid outlet provided on another side of the housing.

[0017] A method for controlling a battery module according to an embodiment of the present invention may include detecting a pressure of a fluid filled to immerse a plurality of secondary batteries built into a housing using a pressure sensor, and pressurizing the fluid using a pressurizing unit based on a detection result of the pressure sensor.

[0018] The pressurizing step may include sensing an increase in pressure of the fluid with the pressure sensor.

[0019] The pressurizing step may include a step of: a control unit acquiring a pressure value sensed using the pressure sensor; and a step of controlling the pressurizing unit to pressurize the fluid at a pressure equal to or exceeding a degree of pressure increase of the fluid based on the pressure value acquired by the control unit. [Effects of the Invention]

[0020] According to a preferred embodiment of the present invention, the swelling phenomenon can be effectively suppressed.

[0021] According to preferred embodiments of the present invention, structural stability can be improved. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a vertical cross-sectional view showing the structure of a battery module according to an embodiment of the present invention. [Figure 2] 4 is a flowchart illustrating a control flow of a battery module according to an embodiment of the present invention. [Figure 3] 4 is a longitudinal cross-sectional view illustrating a state in which the volume of some of a plurality of secondary batteries has increased according to an embodiment of the present invention; FIG. [Figure 4] 4 is a vertical cross-sectional view showing a state in which a fluid is pressurized using a pressurizing unit according to an embodiment of the present invention; FIG. [Figure 5] FIG. 10 is a longitudinal sectional view showing the structure of a battery module according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023]

[0033] The present invention will now be described in detail with reference to the accompanying drawings, in which:

[0034] A preferred embodiment of the present invention will be described in detail so that those skilled in the art can easily implement the present invention; however, the present invention may be embodied in various different forms and is not limited to the following embodiments.

[0024] In order to clearly explain the present invention, detailed descriptions of parts that are not relevant to the explanation or related known technologies that may unnecessarily obscure the gist of the present invention will be omitted, and when adding reference symbols to components in each drawing in this specification, the same or similar reference symbols will be used for the same or similar components throughout the specification.

[0025] Furthermore, the terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted as meanings and concepts that are consistent with the technical idea of ​​the present invention, in accordance with the principle that an inventor can define the concept of a term as appropriate in order to best explain his or her invention.

[0026] FIG. 1 is a diagram showing the structure of a battery module according to one embodiment of the present invention.

[0027] The battery module 1 may include a housing 10. The housing 10 may form an outer casing of the battery module 1. The housing 10 may have an accommodating space formed therein in which a plurality of secondary batteries 20 may be accommodated.

[0028] The battery module 1 can include a plurality of secondary batteries 20. The plurality of secondary batteries 20 can be housed in a housing 10.

[0029] The battery module 1 may contain a fluid 30. For example, the housing 10 of the battery module 1 may contain a fluid. The fluid 30 may be contained inside the housing 10 so that the multiple secondary batteries 20 are immersed therein.

[0030] Various types of fluid may be used as the fluid 30. The fluid 30 provided inside the housing 10 may be a liquid or a gas.

[0031] The fluid 30 may include an incompressible fluid. When the fluid 30 is an incompressible fluid, pressure (e.g., pressurized pressure) may be transmitted more effectively.

[0032] Fluid 30 may be a fire-retardant fluid. If fluid 30 is a fire-retardant fluid, the risk of fire may be reduced and chemical stability may be improved.

[0033] Such a flame-retardant fluid is a fluid composed of a non-flammable material and various types may be used. For example, an ionic liquid may be used as the flame-retardant fluid. Ionic liquids form ionic bonds between cations and anions, and therefore are less likely to volatilize at high temperatures and have excellent heat resistance. Ionic liquids may be composed of organic cations and inorganic or organic anions.

[0034] Such organic cations can have a variety of structures, such as pyridinium, imidazolium, pyrrolidinium, ammonium, phosphonium, and sulfonium, each of which has a central element such as N, P, or S.

[0035] The anions of the ionic liquid may be of various types. For example, the anions include hexafluorophosphate (PF6 - ), triflate(CF3SO3 - ), tetrafluoroborate (BF4 -Fluorine-based anions such as ) may be used.

[0036] The flame-retardant fluid may be silicone oil, etc. Silicon oil is stable against oxidation, so it can prevent the surfaces of the secondary batteries 20 from being oxidized, and has the advantageous effect of not catching fire even under high-temperature conditions due to its excellent heat resistance.

[0037] Alternatively, the fluid 30 may be a Freon (registered trademark) refrigerant having high thermal stability or a non-toxic and stable hydrocarbon refrigerant.

[0038] The battery module 1 may include a pressurizing unit 40. The pressurizing unit 40 may be provided to apply pressure to the fluid 30. The pressurizing unit 40 may be provided to be movable relative to the fluid 30. For example, the pressurizing unit 40 may be installed in the housing 10 to be able to pressurize the fluid 30.

[0039] The pressurizing unit 40 is installed in the housing 10 and moves relative to the fluid 30 to pressurize or release the pressure on the fluid 30 .

[0040] For example, the pressurizing unit 40 is installed on the upper side of the housing 10 and can move up and down to pressurize or release the pressure on the fluid 30. Specifically, when the pressurizing unit 40 moves downward, the storage space in the housing 10 in which the fluid 30 is stored decreases, so the fluid 30 may be pressurized. Also, when the pressurizing unit 40 moves upward, the storage space in the housing 10 in which the fluid 30 is stored expands again, so the pressure on the fluid 30 may be released.

[0041] The pressurizing unit 40 can move toward the inside of the battery module 1 (or the housing 10) to apply pressure to the fluid 30. In addition, the pressurizing unit 40 can move toward the outside of the battery module 1 (or the housing 10) to release the pressure on the fluid 30 or reduce the level of pressure.

[0042] The degree of pressure applied to the fluid 30 may vary depending on the degree to which the pressurizing unit 40 is inserted into the battery module 1 (or the housing 10). For example, the degree to which the pressurizing unit 40 is inserted into the battery module 1 (or the housing 10) may be greater.

[0043] There are no particular limitations on the method or form of realizing relative movement of the pressurizing unit 40 as long as it has a structure that can pressurize a certain volume inside the battery module 1. For example, the pressurizing unit 40 may be provided to be movable relative to the fluid 30, including a piston, but is not limited thereto.

[0044] The pressure member 40 may have various shapes. For example, the pressure member 40 may have a cylindrical rod shape. When the pressure member 40 has a cylindrical rod shape, all of the portions that come into contact with the housing 10 are formed with curved surfaces, thereby minimizing damage to the housing 10 when the pressure member 40 moves up and down.

[0045] The battery module 1 may include a pressure sensor 50. The pressure sensor 50 may be provided to sense the pressure (e.g., pressure value, pressure change) of the fluid 30. For example, the pressure sensor 50 may be provided with one end in contact with the fluid 30 to sense the pressure. The pressure sensor 50 may also be installed in the housing 10.

[0046] The pressurizing unit 40 may be configured to pressurize the fluid 30 based on the detection result of the pressure sensor 50. For example, the battery module 1 may be electrically connected to an external control unit (not shown), and the pressurizing unit 40 and the pressure sensor 50 may also be electrically connected to the control unit. The control unit may determine the degree of pressurization based on the pressure value acquired from the pressure sensor 50 and may transmit the determined degree of pressurization to the pressurizing unit 40. The pressurizing unit 40 may pressurize the fluid 30 at the determined degree of pressurization.

[0047] Various types of pressure sensors may be used for the pressure sensor 50. For example, an electronic sensor that converts the sensed pressure into an electrical signal to obtain a switching output may be used for the pressure sensor 50. Alternatively, a mechanical sensor that converts pressure into a displacement to obtain a switching output may be used for the pressure sensor 50.

[0048] FIG. 2 is a flowchart illustrating a method for controlling a battery module according to an embodiment of the present invention.

[0049] The control flow shown in FIG. 2 will be described with reference to FIG. 3, which shows an increased volume of some of a plurality of secondary batteries according to an embodiment of the present invention, and FIG. 4, which shows pressurizing a fluid using a pressurizing unit according to an embodiment of the present invention.

[0050] The contents of the above-described embodiment may be applied in the same or similar manner to this embodiment.

[0051] According to S100, the control method for the battery module 1 may include a step of sensing, using a pressure sensor 50, the pressure of the fluid 30 filled to immerse the plurality of secondary batteries 20 housed in the housing 10.

[0052] 3, an increased volume region T may occur in some of the secondary batteries 20. The increased volume region T may be formed by gas generation from some of the secondary batteries 20 during charging and discharging.

[0053] When the volume-increased region T is formed, a pressure corresponding to the increase in volume of the volume-increased region T may be transmitted to the fluid 30. If the fluid 30 is formed into an incompressible liquid, the pressure transmission may be more effective.

[0054] The pressure sensor 50 can sense the pressure of the fluid 30 that has increased due to the volume-increased region T. The pressure sensor 50 can sense the pressure of the fluid 30 (for example, an increase or decrease in pressure) in real time.

[0055] Although the above description has been given in the embodiment in which the volume-increased region T is formed, the definition of a specific region is not necessarily required. The above description may be generally applied to a region or part to which the pressure of the fluid 30 is transmitted when a swelling phenomenon occurs due to gas generation.

[0056] According to S200 , the control method for the battery module 1 may include a step of pressurizing the fluid 30 using the pressurizing unit 40 based on the sensing result of the pressure sensor 50 .

[0057] The pressurizing step may include a process in which the pressure sensor 50 senses an increase in pressure of the fluid 30. In other words, the sensing result of the pressure sensor 50 may include the sensing of an increase in pressure of the fluid 30.

[0058] The pressurizing step may include a process in which the control unit acquires a pressure value sensed using the pressure sensor 50.

[0059] The pressurizing step may include a process of controlling the pressurizing unit 40 to pressurize the fluid 30 at a pressurizing pressure (or a degree of pressurization) that is equal to or exceeds the degree of pressure increase of the fluid 30 based on the pressure value acquired by the control unit.

[0060] Referring to FIG. 4, under the control of the control unit, the pressurizing unit 40 can pressurize the fluid 30 at a pressure equal to or exceeding the degree of pressure increase of the fluid 30 sensed by the pressure sensor 50 .

[0061] The pressurizing unit 40 can move relative to the fluid 30 to apply or release pressure to the fluid 30. For example, as shown in Fig. 4, the pressurizing unit 40 can pressurize the fluid 30 by moving in the vertical direction. However, there are no particular limitations on the direction of movement of the pressurizing unit 40 as long as it can move relative to the fluid 30 to apply pressure.

[0062] For example, the pressurizing unit 40 provided on the upper side of the housing 10 can move downward to pressurize the fluid 30 and move upward to release the pressure on the fluid 30. Such vertical movement of the pressurizing unit 40 may be performed by an operator or a robot arm.

[0063] The pressurizing unit 40 may move toward the inside of the battery module 1 (or the housing 10) with a pressure equal to or exceeding the degree of pressure increase of the fluid 30 sensed by the pressure sensor 50, thereby pressurizing the fluid 30.

[0064] The pressurizing unit 40 can move toward the outside of the battery module 1 (or the housing 10) to release the pressure on the fluid 30 or reduce the level of pressure.

[0065] When the pressurizing unit 40 pressurizes the fluid 30, the pressurizing pressure may be transmitted to some (e.g., the volume-increased region T) of the plurality of secondary batteries 20 via the fluid 30. When the pressurizing pressure is transmitted to some (e.g., the volume-increased region T) of the plurality of secondary batteries 20, further generation of gas may be suppressed.

[0066] As described above, the pressure applied by the pressure unit 40 can effectively suppress swelling of some of the secondary batteries 20. In other words, it can suppress volumetric changes of the secondary batteries 20. This can improve the structural stability of the secondary batteries 20 or the battery module 1.

[0067] Specifically, when the pressurizing unit 40 pressurizes the fluid 30 in the housing 10, the pressure of the fluid 30 may be the same as or similar to the withstand pressure of the secondary battery 20. In this case, volumetric changes in the secondary battery 20 may be suppressed, and the overall structural stability of the secondary battery 20 and the battery module 1 may be improved.

[0068] 5 is a diagram showing the structure of a battery module according to another embodiment of the present invention. The contents of the above-described embodiments may be applied in the same or similar manner to this embodiment.

[0069] The battery module 1a may further include a fluid inlet 60a. The fluid inlet 60a may be provided on one side of the housing 10a. The fluid 30a may flow into the housing 10a through the fluid inlet 60a.

[0070] The battery module 1a may include a fluid discharge portion 70a. The fluid discharge portion 70a may be provided on another side of the housing 10a. The fluid 30a may be discharged to the outside of the housing 10a through the fluid discharge portion 70a.

[0071] When the battery module 1a is provided with the fluid inlet 60a and the fluid outlet 70a, the fluid 30a can circulate, and the circulation of the fluid 30a can effectively cool the plurality of secondary batteries 20a.

[0072] In addition, if the pressurizing effect or cooling effect due to the denaturation of the fluid 30a is inefficient, the fluid 30a can be newly supplied to the battery module 1a via the fluid inlet 60a and the fluid outlet 70a.

[0073] Although the present invention has been described above using limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible within the technical spirit of the present invention and the scope of the claims set forth below by a person having ordinary skill in the art to which the present invention pertains. [Explanation of symbols]

[0074] 1, 1a: Battery module 10, 10a: Housing 20, 20a: Multiple secondary batteries 30, 30a: Fluid 40, 40a: Pressurizing section 50, 50a: Pressure sensor 60a: Fluid inlet 70a: Fluid outlet T: Volume increase region

Claims

1. Housing and a plurality of secondary batteries housed in the housing; a fluid provided inside the housing so as to immerse the plurality of secondary batteries; a pressurizing unit configured to apply pressure to the fluid.

2. The pressure applying unit is The battery module according to claim 1 , wherein the battery module is disposed in the housing so as to be movable relative to the fluid.

3. The fluid is The battery module of claim 1 , comprising an incompressible fluid.

4. The battery module according to claim 1 , further comprising a pressure sensor configured to sense a change in pressure of the fluid.

5. The pressure sensor The battery module according to claim 4 , wherein the battery module is installed in the housing so that one end thereof is in contact with the fluid for sensing a pressure change of the fluid.

6. The pressure applying unit is The battery module according to claim 4 , wherein the fluid is pressurized based on a sensing result of the pressure sensor.

7. The pressure applying unit is The battery module according to claim 6 , wherein the fluid is pressurized at a pressure equal to or exceeding the degree of pressure increase of the fluid sensed by the pressure sensor.

8. The fluid is The battery module according to claim 1 , wherein the fluid is a flame-retardant fluid.

9. The fluid is The battery module according to claim 1 , wherein the oil is silicone oil.

10. a fluid inlet provided on one side of the housing; The battery module according to claim 1 , further comprising: a fluid discharge portion provided on another side of the housing.

11. sensing a pressure of a fluid filled to immerse the plurality of secondary batteries housed in the housing using a pressure sensor; and pressurizing the fluid using a pressurizing unit based on a result of sensing by the pressure sensor.

12. The pressurizing step includes: The method of claim 11 , further comprising the step of: the pressure sensor sensing an increase in pressure of the fluid.

13. The pressurizing step includes: a step of a control unit acquiring a pressure value sensed using the pressure sensor; 12. The method of claim 11, further comprising: controlling the pressurizing unit to pressurize the fluid to a pressure equal to or exceeding a degree of pressure increase of the fluid based on the acquired pressure value.

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