Battery pack and electric device

Abstract

The utility model discloses a battery pack and an electric device, and relates to the technical field of batteries. The battery pack comprises a shell, a battery module and a fire extinguishing assembly, the battery module is arranged in the shell, the battery module comprises a plurality of battery cells, and first anti-explosion valves of the plurality of battery cells are arranged upwards; the fire extinguishing assembly comprises a fire extinguishing capsule, the fire extinguishing capsule comprises an outer skin and a fire extinguishing agent arranged in the outer skin, and when the battery cell is in thermal runaway, the outer skin is broken to enable the fire extinguishing agent to be sprayed out. The battery pack can control the fire at the initial stage of thermal runaway of the battery cells, so that the spreading of thermal runaway is avoided, and the safety is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery pack and an electric device. Background Art

[0002] In the development process of batteries, lithium-ion batteries are increasingly applied to the energy storage field due to their advantages such as high capacity, high output voltage, good discharge cycle performance, and safe use. The existing energy storage system uses a box body made of metal plates as the main structure. Multiple battery packs are arranged in the energy storage box body and are connected to the power grid for use.

[0003] During operation, a single cell of the battery pack is prone to thermal runaway due to reasons such as aging and overload, leading to safety accidents. In the prior art, fire protection mainly relies on smoke sensors and temperature detectors installed on the box body to detect, and fire extinguishing is carried out through fire pipelines. However, the detection of smoke sensors and temperature detectors has hysteresis, and it is impossible to intervene early and extinguish the fire in the first time. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a battery pack and an electric device, which can control the fire at the initial stage of thermal runaway of the cell, avoid the spread of thermal runaway, and improve safety.

[0005] To achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A battery pack includes:

[0007] A housing;

[0008] A battery module disposed in the housing, the battery module including a plurality of cells, and the first explosion-proof valves of the plurality of cells are all arranged upward;

[0009] A fire extinguishing component, the fire extinguishing component including a fire extinguishing capsule, the fire extinguishing capsule including an outer skin and a fire extinguishing agent disposed in the outer skin, and the outer skin is configured to rupture when the cell is thermally out of control so that the fire extinguishing agent is ejected.

[0010] As an optional solution of the above battery pack, the outer skin is configured to rupture when the temperature reaches 130 - 150 °C.

[0011] As an optional solution of the above battery pack, the outer skin is formed by at least two layers of shells sleeved in sequence.

[0012] As an optional solution of the above battery pack, the fire extinguishing capsule is fixedly disposed in the housing and located between the top surface of the battery module and the housing; or

[0013] The fire extinguishing capsule is fixedly disposed on the top surface of the battery module.

[0014] As an alternative to the above battery pack, the fire extinguishing agent is perfluorohexanone or heptafluoropropane.

[0015] As an alternative to the above battery pack, the fire extinguishing assembly includes a plurality of the fire extinguishing capsules, each of the fire extinguishing capsules having a fire extinguishing range, and the fire extinguishing ranges of the plurality of fire extinguishing capsules completely cover the top surface of the battery module.

[0016] As an alternative to the above battery pack, the shape of the fire extinguishing capsule is rectangular, circular, pentagonal or hexagonal.

[0017] As an alternative to the above battery pack, the housing includes an upper cover and a bottom plate, the bottom plate includes a liquid cooling plate, the upper cover is detachably connected to the liquid cooling plate, and the battery module is disposed on the liquid cooling plate and is in heat transfer connection with the liquid cooling plate.

[0018] As an alternative to the above battery pack, the housing further includes a sealing strip, and the sealing strip is disposed along the circumference of the bottom plate and is located between the bottom plate and the upper cover.

[0019] An electrical device, the electrical device includes the battery pack described above.

[0020] Advantages of the present utility model:

[0021] The present utility model provides a battery pack and an electrical device. When a thermal runaway occurs in the battery cells of the battery pack, since the heat in the battery cells cannot be transferred out in time, the internal pressure and temperature of the battery cells rise, causing the first explosion-proof valve of the battery cells to rupture. The high-temperature and high-pressure gas and liquid ejected from the first explosion-proof valve of the battery cells will cause the internal temperature of the battery pack to rise, or directly eject onto the fire extinguishing capsule, causing the outer skin of the fire extinguishing capsule to rupture, so that the fire extinguishing agent is ejected. Since the first explosion-proof valves of the battery cells are all arranged upward, the fire extinguishing agent can flow to the explosion-proof valves of the battery cells with thermal runaway to extinguish the fire and slow down the spread of the fire.

[0022] The battery pack can control the fire at the initial stage of thermal runaway of the battery cells, avoid the spread of thermal runaway, and improve safety. Description of the Drawings

[0023] Figure 1 is a schematic structural view of the battery pack provided by the present utility model;

[0024] Figure 2 is an exploded view of the battery pack provided by the present utility model;

[0025] Figure 3 is a schematic structural view of the bottom plate provided by the present utility model;

[0026] Figure 4 is an exploded view of the bottom plate provided by the present utility model;

[0027] Figure 5 is Figure 2 The partial enlarged view of position A in it.

[0028] In the figure:

[0029] 1. Outer shell; 2. Battery module; 3. Fire extinguishing component; 4. Second explosion-proof valve;

[0030] 11. Upper cover; 12. Bottom plate; 21. Battery cell; 31. Fire extinguishing capsule;

[0031] 111. Convex hull; 121. Liquid cooling plate; 122. Sealing strip; 123. Limit cross beam; 211. First explosion-proof valve. Detailed implementation manners

[0032] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the drawings, in which the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present utility model, and should not be construed as a limitation to the present utility model.

[0033] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0034] Unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", "fixation" should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0035] Unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the first feature and the second feature being in direct contact, or may include the first feature and the second feature not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and diagonally above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "beneath" and "underneath" the second feature includes the first feature being directly below and diagonally below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0036] The technical solution of the present utility model will be further described below in conjunction with the accompanying drawings and through specific embodiments.

[0037] In the development process of batteries, lithium-ion batteries are increasingly applied to the energy storage field due to their advantages such as high capacity, high output voltage, good discharge cycle performance, and safe use. The existing energy storage system has a box body made of metal plates as the main structure, and multiple battery packs are arranged in the energy storage box body, and the multiple battery packs are connected to the power grid for use.

[0038] This embodiment provides an electrical device, which includes a cabinet body and a battery pack. As Figure 1 and Figure 2 shown, the battery pack includes a housing 1 and a battery module 2. The battery module 2 is arranged in the housing 1, and the housing 1 can protect the internal structure of the battery pack. The battery module 2 includes a plurality of battery cells 21, and the plurality of battery cells 21 are electrically connected in series and / or in parallel to obtain appropriate electric quantity and output voltage to ensure the normal use of the battery pack.

[0039] In this embodiment, the electrical device is described by taking an energy storage cabinet as an example.

[0040] As Figures 2 to 4 shown, the housing 1 includes an upper cover 11 and a bottom plate 12. The bottom plate 12 includes a liquid cooling plate 121. The upper cover 11 is detachably connected to the liquid cooling plate 121, and the battery module 2 is arranged on the liquid cooling plate 121 and is heat transfer connected to the liquid cooling plate 121. Among them, a liquid cooling pipeline is arranged inside the liquid cooling plate 121, and a coolant circulates in the liquid cooling pipeline. The coolant flows through the liquid cooling plate 121 to take away the heat of the battery module 2, so that the battery cells 21 in the battery module 2 are in the best working temperature. Generally speaking, the working temperature range of the battery cells 21 is -20°C to 55°C.

[0041] Using the liquid cooling plate 121 as the supporting structure of the battery module 2 can reduce one layer of plate body, thereby reducing the weight and volume of the battery pack, increasing the energy density of the battery pack, and also reducing the material cost.

[0042] Furthermore, a thermal conductive adhesive is provided on the liquid cooling plate 121. The thermal conductive adhesive is laid flat above the liquid cooling plate 121 and adhesively fixed to the battery cells 21 in the battery module 2. The thermal conductive adhesive can not only fix the battery module 2, but also transfer the heat generated by the operation of the battery module 2 to the liquid cooling plate 121, improving the heat exchange efficiency and effectively preventing the abnormal working temperature of the battery cells 21 from affecting the lifespan of the battery cells 21.

[0043] It should be noted that the thermal conductive adhesive fully fills the gap between the liquid cooling plate 121 and the battery cells 21, preventing the generation of air bubbles from affecting the heat conduction effect.

[0044] As Figure 3 and Figure 4 shown, a limiting crossbeam 123 is also provided on the liquid cooling plate 121. The battery module 2 is fixed to the limiting crossbeam 123 by screws. Moreover, the limiting crossbeam 123 can ensure that there is a space for filling the thermal conductive adhesive between the battery module 2 and the liquid cooling plate 121, and at the same time keep the battery module 2 and the liquid cooling plate 121 stable.

[0045] In this embodiment, at least two limiting crossbeams 123 are provided on the liquid cooling plate 121 to ensure the stability of the battery module 2.

[0046] As Figure 3 and Figure 4 shown, the housing 1 further includes a sealing strip 122. The sealing strip 122 is arranged along the circumference of the liquid cooling plate 121 and is located between the liquid cooling plate 121 and the upper cover 11. The sealing strip 122 can ensure the sealing of the entire battery pack, preventing external dust and moisture from entering the interior of the battery device, so as to improve the service life of the battery pack.

[0047] As Figure 1 and Figure 2 shown, a plurality of convex bumps 111 are provided on the top surface of the upper cover 11 to improve the overall strength of the upper cover 11 and prevent the top surface of the upper cover 11 from collapsing and affecting the internal battery module 2 or circuit. It should be noted that the convex bumps 111 can bulge upward or downward, both of which can play a role in improving the strength.

[0048] In this embodiment, the energy storage cabinet further includes a fire protection system and a fire detection component. The fire protection system and the fire detection component are both arranged inside the cabinet. The fire protection system is communicatively connected to the fire detection component. The fire detection component includes a smoke detector and / or a temperature sensor. When the battery cells 21 undergo thermal runaway, accompanied by the generation of smoke and an increase in temperature, at this time, the smoke detector and / or the temperature sensor can send a signal to the fire protection system, and the fire protection system starts the fire extinguishing operation.

[0049] However, the operation of fire fighting mainly relying on the smoke sensors and temperature detectors set in the box to detect and extinguish fires through the fire pipeline has a lag, and it is impossible to directly extinguish the fire for the thermally out-of-control battery cell 21, and it is impossible to intervene early and extinguish the fire in the first time, resulting in a high safety risk.

[0050] As Figure 2 and Figure 5 shown, to solve the above problems, the battery pack provided in this embodiment includes a fire extinguishing component 3. The first explosion-proof valves 211 of multiple battery cells 21 are all arranged upward. The fire extinguishing component 3 includes a fire extinguishing capsule 31. The fire extinguishing capsule 31 includes an outer skin and a fire extinguishing agent arranged inside the outer skin. The outer skin is configured to rupture when the battery cell 21 is thermally out of control so that the fire extinguishing agent is ejected.

[0051] When the battery cell 21 in the battery pack is thermally out of control, due to the heat in the battery cell 21 not being able to be transferred out in time, the internal pressure and temperature of the battery cell 21 rise, causing the first explosion-proof valve 211 of the battery cell 21 to rupture. The high-temperature and high-pressure gas and liquid ejected from the first explosion-proof valve 211 of the battery cell 21 will cause the internal temperature of the battery pack to rise, or directly spray onto the fire extinguishing capsule 31, causing the outer skin of the fire extinguishing capsule 31 to rupture, so that the fire extinguishing agent is ejected. Since the first explosion-proof valves 211 of the battery cells 21 are all arranged upward, the fire extinguishing agent can flow to the explosion-proof valve of the thermally out-of-control battery cell 21 to extinguish the fire and slow down the spread of the fire.

[0052] This battery pack can control the fire at the initial stage of thermal runaway of the battery cell 21, avoid the spread of thermal runaway, and improve safety.

[0053] In order to enable the fire extinguishing capsule 31 to extinguish the fire for the battery cell 21 with abnormal temperature as early as possible and ensure the safety of the battery pack, the heat-resistant temperature of the outer skin cannot be too high. In this embodiment, the outer skin is configured to rupture when the temperature exceeds 130°C. The temperature of 130°C is higher than the normal working range of the battery cell 21, which can effectively avoid the situation of mis-triggering caused by the temperature of the battery cell 21 rising briefly above 55°C during operation, and ensure the reliability and timeliness of the fire extinguishing capsule 31.

[0054] In this embodiment, the fire extinguishing agent is perfluoromethyl isopropyl ketone or heptafluoropropane. Both have fluidity and can flow to the thermally out-of-control battery cell 21, and at the same time play the role of cooling and isolating oxygen. They can not only extinguish the fire, but also quickly reduce the temperature of the thermally out-of-control battery cell 21 to avoid the spread of the fire.

[0055] In this embodiment, the outer skin is formed by at least two layers of shells sleeved in sequence. Specifically, when designing the number of layers of the outer skin, it can be customized according to the specific parameters of the battery pack, so that the rupture temperature and rupture speed of the outer skin meet the design requirements.

[0056] Among them, the housing is made of polymer materials. Specifically, the polymer materials include one or more of natural polymers, semi-synthetic polymers, and synthetic polymers, and each layer can be independently selected according to needs. It should be noted that the natural polymers are one or more of gelatin, sodium alginate, chitosan, gum arabic, polyglutamic acid, and β-cyclodextrin; the semi-synthetic polymers are one or more of sodium carboxymethyl cellulose, hydroxypropyl methylcellulose, and octenyl succinic anhydride esterified starch; the synthetic polymers are one or more of polymethacrylate, epoxy resin, polyurethane, phenolic resin, acrylic resin, furan resin, resorcinol-formaldehyde resin, xylene-formaldehyde resin, unsaturated polyester, and polyimide.

[0057] In this embodiment, the rupture temperature of the housing preferably activates the fire extinguishing function when it ruptures at 130°C to 150°C.

[0058] In this embodiment, in order to ensure that the fire extinguishing capsule 31 can extinguish the fire of the thermally out-of-control battery cell 21, the fire extinguishing capsule 31 needs to be arranged between the top surface of the battery module 2 and the outer shell 1. If the outer skin of the fire extinguishing capsule 31 ruptures, the fire extinguishing agent can flow on the top surface of the battery module 2. Therefore, the fire extinguishing capsule 31 needs to be fixedly arranged on the outer shell 1 and between the top surface of the battery module 2 and the outer shell 1, or the fire extinguishing capsule 31 needs to be fixedly arranged on the top surface of the battery module 2. Among them, the fire extinguishing capsule 31 is fixed to the top surface of the battery module 2 or the outer shell 1 through a colloid.

[0059] In this embodiment, the fire extinguishing assembly 3 includes a plurality of fire extinguishing capsules 31, and each fire extinguishing capsule 31 has a fire extinguishing range. The fire extinguishing ranges of the plurality of fire extinguishing capsules 31 completely cover the top surface of the battery module 2. It can be understood that the above setting method can ensure that when any battery cell 21 is thermally out of control, the outer skin of the corresponding fire extinguishing capsule 31 nearby ruptures to release the fire extinguishing agent, so as to extinguish the fire of the thermally out-of-control battery cell 21.

[0060] Specifically, as Figure 2 shown, along the length direction of the battery pack, three rows of fire extinguishing capsules 31 are equally spaced on the battery pack, and each row of fire extinguishing capsules 31 is provided with two. That is to say, six fire extinguishing capsules 31 can ensure the safety of the battery pack. In some embodiments, according to the size of the battery pack, the number of fire extinguishing capsules 31 to be set is also different, which will not be elaborated here one by one.

[0061] In this embodiment, the shape of the fire extinguishing capsule 31 is rectangular, circular, pentagonal or hexagonal. The shape of the fire extinguishing capsule 31 can be selected according to the structure of the battery module 2 to ensure that the fire extinguishing capsule 31 fits the top surface structure of the battery pack and avoid local interference from causing the outer skin to be scratched and the fire extinguishing agent to leak. It can be understood that the shape of the fire extinguishing capsule 31 can also be irregular, which will not be elaborated here.

[0062] AsFigure 1 and Figure 2 As shown, the battery pack further includes a second explosion-proof valve 4. The second explosion-proof valve 4 is arranged on the upper cover 11. The second explosion-proof valve 4 is used to balance the air pressure inside and outside the housing 1, maintaining the pressure balance inside and outside the battery pack. When serious thermal runaway or fire occurs in the battery pack, the second explosion-proof valve 4 can quickly discharge the high-pressure gas inside to the outside through the second explosion-proof valve 4, avoiding the explosion caused by the excessive internal pressure out of control of the battery pack and improving safety.

[0063] The above content is only the preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. The content of this specification should not be construed as a limitation to the present invention.

Claims

1. A battery pack, characterized in that: include: Housing (1); A battery module (2) is arranged in the housing (1), the battery module (2) comprising a plurality of battery cells (21), and the first explosion-proof valves (211) of the plurality of battery cells (21) are all arranged upwards; A fire extinguishing assembly (3) comprising a fire extinguishing capsule (31), the fire extinguishing capsule (31) comprising an outer skin and a fire extinguishing agent disposed within the outer skin, the outer skin being configured to rupture when the battery cell (21) thermally runs away so as to allow the fire extinguishing agent to spray out.

2. The battery pack according to claim 1, characterized in that: The skin is configured to rupture when temperatures reach 130-150°C.

3. The battery pack according to claim 1, characterized in that: The outer skin is formed by at least two layers of shells being sheathed in sequence.

4. The battery pack according to claim 1, characterized in that: The fire extinguishing capsule (31) is fixedly arranged on the outer shell (1) and is located between the top surface of the battery module (2) and the outer shell (1); or The fire extinguishing capsule (31) is fixedly arranged on the top surface of the battery module (2).

5. The battery pack according to claim 1, characterized in that: The fire extinguishing agent is perfluorohexanone or heptafluoropropane.

6. The battery pack according to claim 1, characterized in that: The fire extinguishing assembly (3) comprises a plurality of fire extinguishing capsules (31), each of the fire extinguishing capsules (31) having a fire extinguishing range, and the fire extinguishing ranges of the plurality of fire extinguishing capsules (31) completely cover the top surface of the battery module (2).

7. The battery pack according to claim 1, characterized in that: The shape of the fire extinguishing capsule (31) is rectangular, circular, pentagonal or hexagonal.

8. The battery pack according to any one of claims 1 to 7, characterized in that: The housing (1) comprises an upper cover (11) and a bottom plate (12); the bottom plate (12) comprises a liquid cooling plate (121); the upper cover (11) and the liquid cooling plate (121) are detachably connected; and the battery module (2) is disposed on the liquid cooling plate (121) and is heat-transferably connected to the liquid cooling plate (121).

9. The battery pack according to claim 8, characterized in that: The housing (1) further comprises a sealing strip (122), wherein the sealing strip (122) is arranged along the circumference of the bottom plate (12) and is located between the bottom plate (12) and the upper cover (11).

10. An electrical device, characterized in that: The electric device comprises the battery pack according to any one of claims 1 to 9.

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