Battery system

Abstract

The utility model discloses a battery system which comprises a battery box and a pressure relief chamber, a battery, a phase change material and a first heat exchange structure are contained in the battery box, the phase change material is heated and gasified, the first heat exchange structure is used for cooling the gasified phase change material, the battery box is communicated with the pressure relief chamber, and the pressure relief chamber is communicated with the battery box. And when the internal air pressure of the battery box reaches an air pressure threshold value, air is exhausted to the pressure relief chamber for pressure relief. According to the utility model, the damage to the battery caused by overlarge air pressure in the battery box is avoided, and the stability and reliability of the battery are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery system. Background Art

[0002] As the core component of electric vehicles, power batteries have always been an important link in my country's new energy vehicle industry chain, and battery charging time has become a major concern for consumers when purchasing and driving electric vehicles.

[0003] When the battery charging time is compressed, the heat released by the battery per unit time will increase significantly. Under the premise that the battery material remains unchanged, enhancing the heat dissipation capacity of the battery pack becomes a top priority. The existing technology has a technical solution to dissipate heat by evaporating liquid phase change materials in the battery box, but when the liquid phase change material is excessively vaporized, it will cause excessive air pressure in the battery box and cause damage to the battery. Utility Model Content

[0004] In order to overcome the shortcomings and deficiencies in the prior art, the purpose of the utility model is to provide a battery system to avoid damage to the battery caused by excessive air pressure in the battery box and to improve the stability and reliability of the battery.

[0005] The purpose of the utility model is achieved through the following technical solutions:

[0006] A battery system comprises a battery box and a pressure relief chamber, wherein the battery box contains a battery, a phase change material and a first heat exchange structure, wherein the phase change material is vaporized by heat, and the first heat exchange structure is used to cool the vaporized phase change material, and the battery box is connected to the pressure relief chamber, and when the internal air pressure of the battery box reaches an air pressure threshold, the air is exhausted and pressure is relieved to the pressure relief chamber.

[0007] In one embodiment, the pressure relief chamber is connected to the battery box through a pressure relief passage. The pressure relief passage is provided with a first one-way valve that conducts from the battery box to the pressure relief chamber, and is used to exhaust and relieve pressure to the pressure relief chamber when the internal air pressure of the battery box reaches an air pressure threshold.

[0008] In one embodiment, the pressure relief passage is connected to the top of the battery box.

[0009] In one embodiment, the pressure relief passage is configured as a pipeline structure, and along the conducting direction of the first one-way valve, the downstream end of the pressure relief passage is located in the pressure relief chamber and is arranged close to the top of the pressure relief chamber.

[0010] In one embodiment, when the internal air pressure of the battery box reaches an air pressure threshold, the first one-way valve opens; wherein the air pressure threshold is the air pressure value in the battery box corresponding to when the battery reaches the upper limit of the normal operating temperature range.

[0011] In one embodiment, a second heat exchange structure is provided in the pressure relief chamber, and the second heat exchange structure is used to cool the gaseous phase change material entering the pressure relief chamber.

[0012] In one embodiment, the battery box and the pressure relief chamber are connected via a reflux passage, and a second one-way valve is provided on the reflux passage, which conducts from the pressure relief chamber to the battery box, so that the phase change material condensed into liquid in the pressure relief chamber can flow back to the battery box.

[0013] In one embodiment, along the conducting direction of the second one-way valve, the upstream end of the reflux passage is connected to the bottom of the pressure relief chamber.

[0014] In one embodiment, along the conducting direction of the second one-way valve, the downstream end of the reflux passage is connected to the top of the battery box.

[0015] In one embodiment, a liquid level sensor is provided in the pressure relief chamber, and the liquid level sensor is used to monitor the liquid level of the phase change material condensed into liquid remaining in the pressure relief chamber. When the liquid level reaches a set liquid level, the liquid level sensor issues an early warning.

[0016] The beneficial effect of the utility model is that the vaporized phase change material is cooled by the first heat exchange structure, so that the battery box has a certain pressure reduction capability. When the first heat exchange structure is not sufficient to control the air pressure in the battery box, the air pressure in the battery box is too high and reaches the air pressure threshold, the air can be discharged to the pressure relief chamber to reduce the air pressure inside the battery box, thereby avoiding damage to the battery due to excessive air pressure in the battery box and improving battery stability and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of a battery system according to an embodiment of the utility model.

[0019] In the figure: 1. battery box; 11. battery; 12. phase change material; 13. first heat exchange structure; 2. pressure relief chamber; 21. second heat exchange structure; 22. liquid level sensor; 3. first one-way valve; 4. pressure relief passage; 41. downstream end of the pressure relief passage; 5. second one-way valve; 6. reflux passage; 61. upstream end of the reflux passage; 62. downstream end of the reflux passage. DETAILED DESCRIPTION

[0020] The following will describe in detail a specific embodiment of the utility model in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments. Based on the description of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] In the description of the present utility model, unless otherwise clearly specified and limited, the terms "set", "install", "connection" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0022] The directions or positional relationships indicated by terms such as "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of description and simplified description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the utility model.

[0023] The terms "first", "second", "third" and the like are merely used to distinguish elements of similar nature, and do not indicate or imply relative importance or a particular order.

[0024] The terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of the elements listed and may also include additional elements not expressly listed.

[0025] The utility model provides a battery system, such as Figure 1 As shown, it includes a battery box 1 and a pressure relief chamber 2. The battery box 1 contains a battery 11, a phase change material 12 and a first heat exchange structure 13. The phase change material 12 is vaporized by heat. The first heat exchange structure 13 is used to cool the vaporized phase change material 12. The battery box 1 is connected to the pressure relief chamber 2. When the internal air pressure of the battery box 1 reaches the air pressure threshold, the air is discharged to the pressure relief chamber 2.

[0026] In this embodiment, the phase change material 12 arranged in the battery box 1 can absorb the heat released by the battery 11 during operation to prevent the battery 11 from being overheated and affecting the normal operation of the battery system. The phase change material 12 vaporizes after absorbing heat, which will cause the air pressure in the battery box 1 to increase. The first heat exchange structure 13 can cool the vaporized phase change material 12. Part of the vaporized phase change material 12 is liquefied, which can reduce the air pressure in the battery box 1, so that the battery box 1 has a certain pressure reduction capability. When the first heat exchange structure 13 is not sufficient to control the air pressure in the battery box 1, the air pressure in the battery box 1 is too high and reaches the air pressure threshold, the battery box 1 can exhaust air to the pressure relief chamber 2 to reduce the air pressure inside the battery box 1, so as to prevent the air pressure in the battery box 1 from being too high and causing damage to the battery 11, thereby improving the reliability and stability of the battery system. Among them, the phase change material 12 before gasification is in liquid state and is in full contact with the battery 11, so that the heat released by the battery 11 during operation can be immediately absorbed by the phase change material 12 to quickly cool the battery 11 and ensure that the battery 11 is continuously within the normal operating temperature range, so that the battery 11 is in a better working state.

[0027] As an implementation mode, the phase change material 12 before gasification can immerse the battery 11. This is beneficial to improve the heat absorption and temperature reduction performance.

[0028] As an implementation mode, the volume of the inner cavity of the battery box 1 is larger than the sum of the volumes of the battery 11 and the phase change material 12 before gasification, so as to provide the phase change material 12 with the space required for gasification.

[0029] As an implementation method, Figure 1 As shown, the pressure relief chamber 2 is connected to the battery box 1 through a pressure relief passage 4, and a first one-way valve 3 is provided on the pressure relief passage 4, which is connected from the battery box 1 to the pressure relief chamber 2, and is used to exhaust and relieve pressure to the pressure relief chamber 2 when the internal air pressure of the battery box 1 reaches the air pressure threshold. Specifically, when the battery box 1 and the pressure relief chamber 2 are closely connected, the pressure relief passage 4 can be a passage that runs through the wall surface where the battery box 1 and the pressure relief chamber 2 are closely connected; when the battery box 1 and the pressure relief chamber 2 are spaced apart, the pressure relief passage 4 can be a pipeline structure.

[0030] As an implementation method, Figure 1 As shown, the pressure relief passage 4 is connected to the top of the battery box 1. Thus, the pressure relief passage 4 is prevented from being blocked by the phase change material 12 before gasification at the position where the pressure relief passage 4 is connected to the battery box 1.

[0031] As an implementation method, Figure 1As shown, the pressure relief passage 4 is configured as a pipeline structure, and along the conduction direction G of the first one-way valve 3 from the battery box 1 to the pressure relief chamber 2, the downstream end 41 of the pressure relief passage 4 is located in the pressure relief chamber 2 and is arranged close to the top of the pressure relief chamber 2. Among them, the downstream end 41 of the pressure relief passage 4 is arranged close to the top of the pressure relief chamber 2 to prevent the pressure relief passage 4 from being blocked by the liquefied phase change material 12 in the pressure relief chamber 2 and affecting the pressure relief of the battery box 1.

[0032] As an implementation mode, when the internal air pressure of the battery box 1 reaches the air pressure threshold, the first one-way valve 3 opens, so that the vaporized phase change material 12 in the battery box 1 can be discharged to the pressure relief chamber 2 through the first one-way valve 3; wherein the air pressure threshold is the air pressure value in the battery box 1 corresponding to when the battery 11 reaches the upper limit of the normal operating temperature range.

[0033] As an implementation method, Figure 1 As shown, the first heat exchange structure 13 is disposed on the top wall of the battery box 1, which is conducive to contacting the vaporized and rising phase change material 12 to improve the cooling efficiency.

[0034] As an implementation method, Figure 1 As shown, a second heat exchange structure 21 is provided in the pressure relief chamber 2, and the second heat exchange structure 21 is used to cool the gaseous phase change material 12 entering the pressure relief chamber 2. In this embodiment, the second heat exchange structure 21 is used to exchange heat and cool down, so as to promote the liquefaction of the gaseous phase change material 12 discharged into the pressure relief chamber 2, which is beneficial to reduce the air pressure in the pressure relief chamber 2, thereby allowing the battery box 1 and the pressure relief chamber 2 to continue to have an air pressure difference, so that the battery box 1 can continue to release pressure and exhaust air into the pressure relief chamber 2.

[0035] As an implementation method, Figure 1 As shown, the battery box 1 and the pressure relief chamber 2 are connected through a reflux passage 6, and a second one-way valve 5 is provided on the reflux passage 6, which is conducted from the pressure relief chamber 2 to the battery box 1, and is used for the phase change material 12 condensed into liquid in the pressure relief chamber 2 to flow back to the battery box 1, so as to realize the recovery of the phase change material 12 and avoid the phase change material 12 in the battery box 1 from decreasing and affecting the cooling of the battery 11. Specifically, when the battery box 1 and the pressure relief chamber 2 are closely connected, the reflux passage 6 can be a channel that passes through the wall surface where the battery box 1 and the pressure relief chamber 2 are closely connected; when the battery box 1 and the pressure relief chamber 2 are spaced apart, the reflux passage 6 can be a pipeline structure.

[0036] As an implementation method, Figure 1As shown, along the conduction direction L of the second one-way valve 5 from the pressure relief chamber 2 to the battery box 1, the upstream end 61 of the reflux passage 6 is connected to the bottom of the pressure relief chamber 2. Among them, the upstream end 61 of the reflux passage 6 is connected to the bottom of the pressure relief chamber 2, which is conducive to the liquid phase change material 12 flowing into the reflux passage 6, and then flowing back to the battery box 1 through the second one-way valve 5, avoiding the problem of excessive liquid phase change material 12 remaining in the pressure relief chamber 2 and difficult to enter the reflux passage 6.

[0037] As an implementation method, Figure 1 As shown, along the conduction direction L of the second one-way valve 5 from the pressure relief chamber 2 to the battery box 1, the downstream end 62 of the reflux passage 6 is connected to the top of the battery box 1, so as to avoid the reflux of the liquefied phase change material 12 in the pressure relief chamber 2 being affected by the obstruction of the liquid phase change material 12 in the battery box 1 when the downstream end 62 of the reflux passage 6 is connected to the lower part of the battery box 1.

[0038] As an implementation method, Figure 1 As shown, a liquid level sensor 22 is provided in the pressure relief chamber 2. The liquid level sensor 22 is used to monitor the liquid level of the phase change material 12 condensed into liquid retained in the pressure relief chamber 2. When the liquid level reaches the set liquid level, the liquid level sensor 22 issues an early warning. In this embodiment, when the liquid level sensor 22 issues an early warning, it can warn the user to reduce the battery power or stop the battery 11 from working to cool the battery 11, so as to avoid the problem that the phase change material 12 in the battery box 1 is too little in the battery box 1 and it is difficult to control the temperature of the battery 11 after excessive gasification and discharge into the pressure relief chamber 2, and then it is too late to flow back to the battery box 1.

[0039] As an implementation mode, the pressure relief chamber 2 is located at the upper part of the battery box 1 .

[0040] As an embodiment, the bottom surface of the pressure relief chamber 2 is not lower than the top surface of the battery box 1, thereby facilitating the gas phase change material 12 in the battery box 1 to enter the pressure relief chamber 2, and facilitating the liquid phase change material 12 in the pressure relief chamber 2 to flow back to the battery box 1. Specifically, the bottom wall of the pressure relief chamber 2 can be the same structure as the top wall of the battery box 1; or, the bottom wall of the pressure relief chamber 2 is arranged in contact with the top wall of the battery box 1; or, there is a gap between the bottom wall of the pressure relief chamber 2 and the top wall of the battery box 1 (such as Figure 1 ).

[0041] As an implementation mode, the withstand voltage value of the battery box 1 is p1, p1 ≥ 0.4Mpa; the withstand voltage value of the pressure relief chamber 2 is p2, p2 ≥ 0.6Mpa, to ensure that when the battery 11 works normally, the battery box 1 and the pressure relief chamber 2 can maintain a normal shape and not deform.

[0042] As an implementation mode, the boiling point of the phase change material 12 is a, 25°C≤a≤45°C. When the operating temperature of the battery 11 is greater than the boiling point of the phase change material 12, the phase change material 12 absorbs heat and vaporizes, thereby reducing the temperature of the battery 11 and preventing the temperature of the battery 11 from continuing to rise and causing thermal runaway.

[0043] As an implementation manner, the second heat exchange structure 21 and / or the first heat exchange structure 13 is a liquid cooling structure, and the second heat exchange structure 21 and / or the first heat exchange structure 13 comprises a liquid inlet and outlet for circulating a heat exchange liquid.

[0044] As an implementation manner, the first heat exchange structure 13 and the second heat exchange structure 21 are each connected with a liquid inlet and outlet for circulating the heat exchange liquid.

[0045] The utility model utilizes a low-boiling-point phase-change material 12 to achieve cooling and heat dissipation of the battery 11, so that the battery 11 is always in the best working environment and the safe operation of the battery system is ensured. When the temperature is higher than the upper limit of the normal working temperature of the battery 11 (such as 45°C), the air pressure in the battery box 1 meets the opening pressure of the first one-way valve 3, the first one-way valve 3 opens, and the gasified phase-change material 12 in the battery box 1 is discharged into the pressure relief chamber 2.

[0046] In this system, when the operating temperature of the battery 11 is higher than 25°C, the phase change material 12 and the first heat exchange structure 13 cooperate to cool the battery 11, the phase change material 12 absorbs the heat released by the battery 11 to vaporize, and the first heat exchange structure 13 cools the vaporized phase change material 12, and part of the vaporized phase change material 12 is liquefied, which can reduce the air pressure in the battery box 1; when the operating temperature of the battery 11 continues to rise to the battery temperature above 45°C, the air pressure in the battery box 1 is too high and reaches the air pressure threshold, and the first one-way valve 3 opens. At this time, the vaporized phase change material 12 in the battery box 1 is discharged into the pressure relief chamber 2. The gaseous phase change material 12 discharged into the pressure relief chamber 2 is cooled and condensed into liquid by the second heat exchange structure 21, and then flows back to the battery box 1 through the second one-way valve 5, thereby realizing the recovery of the phase change material 12.

[0047] When the temperature of the battery 11 continues to be too high, the sum of the air pressure in the pressure relief chamber 2 and the pressure of the condensed phase change material 12 is less than the pressure in the battery box 1, resulting in the second one-way valve 5 being difficult to open or insufficiently opened, and the condensed phase change material 12 in the pressure relief chamber 2 reaches the warning liquid level, and the liquid level sensor 22 issues a warning to remind the user to respond in time, reduce the battery power or stop the battery 11 from working, so as to avoid insufficient phase change material 12 in the battery box 1 affecting the cooling effect and thus affecting the safety of the battery 11.

[0048] The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the profession can make some changes or modifications to the technical contents disclosed above without departing from the scope of the technical solution of the present invention, which are equivalent embodiments of equivalent changes. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. A battery system, characterized in that: The invention comprises a battery box (1) and a pressure relief chamber (2); the battery box (1) contains a battery (11), a phase change material (12) and a first heat exchange structure (13); the phase change material (12) is vaporized by heat; the first heat exchange structure (13) is used to cool the vaporized phase change material (12); the battery box (1) is connected to the pressure relief chamber (2); when the internal air pressure of the battery box (1) reaches an air pressure threshold, the air is exhausted and pressure is relieved to the pressure relief chamber (2).

2. The battery system according to claim 1, characterized in that: The pressure relief chamber (2) is connected to the battery box (1) via a pressure relief passage (4). The pressure relief passage (4) is provided with a first one-way valve (3) which conducts from the battery box (1) to the pressure relief chamber (2) and is used to exhaust and relieve pressure to the pressure relief chamber (2) when the internal air pressure of the battery box (1) reaches an air pressure threshold.

3. The battery system according to claim 2, characterized in that: The pressure relief passage (4) is connected to the top of the battery box (1).

4. The battery system according to claim 2, characterized in that: The pressure relief passage (4) is configured as a pipeline structure. Along the conduction direction (G) of the first one-way valve (3), the downstream end (41) of the pressure relief passage (4) is located in the pressure relief chamber (2) and is arranged close to the top of the pressure relief chamber (2).

5. The battery system according to claim 2, characterized in that: When the internal air pressure of the battery box (1) reaches an air pressure threshold, the first one-way valve (3) opens; wherein the air pressure threshold is the corresponding air pressure value in the battery box (1) when the battery (11) reaches the upper limit of the normal operating temperature range.

6. The battery system according to claim 1, characterized in that: A second heat exchange structure (21) is provided in the pressure relief chamber (2), and the second heat exchange structure (21) is used to cool the gaseous phase change material (12) entering the pressure relief chamber (2).

7. The battery system according to any one of claims 1 to 6, characterized in that: The battery box (1) and the pressure relief chamber (2) are connected via a reflux passage (6), and a second one-way valve (5) is provided on the reflux passage (6) that conducts from the pressure relief chamber (2) to the battery box (1), so as to allow the phase change material (12) condensed into a liquid state in the pressure relief chamber (2) to flow back to the battery box (1).

8. The battery system according to claim 7, characterized in that: Along the conduction direction (L) of the second one-way valve (5), the upstream end (61) of the reflux passage (6) is connected to the bottom of the pressure relief chamber (2).

9. The battery system according to claim 7, characterized in that: Along the conduction direction (L) of the second one-way valve (5), the downstream end (62) of the reflux passage (6) is connected to the top of the battery box (1).

10. The battery system according to claim 1, characterized in that: A liquid level sensor (22) is provided in the pressure relief chamber (2). The liquid level sensor (22) is used to monitor the liquid level of the phase change material (12) condensed into liquid and retained in the pressure relief chamber (2). When the liquid level reaches a set liquid level, the liquid level sensor (22) issues an early warning.

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