Battery pack and energy storage equipment

Abstract

The utility model belongs to the technical field of energy storage equipment, and discloses a battery pack and energy storage equipment. The battery pack comprises a battery assembly, heating pieces and a heat absorption assembly, the battery assembly comprises a plurality of battery cells arranged in an array mode, the heating pieces are arranged on at least one side of the battery assembly in the height direction of the battery assembly, the heat absorption assembly is arranged between the battery cells and makes contact with the battery cells, the heat absorption assembly comprises a packaging piece and a phase change material, and the phase change material is wrapped with the packaging piece. In a low-temperature environment, the plurality of battery cells are heated through the heating piece, so that the battery pack can normally work at a proper temperature; when a large amount of heat is generated in the battery cell, the heat absorption assembly is in contact with the battery cell, and the phase change material can absorb the heat and generate state change, so that the large amount of heat generated in the battery cell is quickly and efficiently taken away, the temperature of the battery cell is reduced, thermal runaway of the battery pack is effectively inhibited, and the stability and the safety of the battery pack are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage equipment, and in particular to a battery pack and energy storage equipment. Background Art

[0002] During the use of the battery pack, if the temperature is too low, some low-temperature byproducts may be generated, which may pierce the cell diaphragm, thereby damaging the cell and posing a safety hazard. Based on this, currently, the battery pack is usually equipped with a heating device to heat it when in use to prevent it from working at a low temperature.

[0003] For cylindrical cells, the most common heating method is to attach a serpentine liquid cooling plate to the cell with glue. In order to achieve uniform heating, all cells and the serpentine liquid cooling plate are closely matched to form a heat-conducting whole. However, the battery pack is required to have the ability to prevent thermal runaway, and the cells need to be thermally isolated. This is a contradiction between heating and insulation, so the battery pack cannot meet the need to prevent thermal runaway.

[0004] Therefore, there is an urgent need to provide a battery pack and energy storage device to solve the above problems. Utility Model Content

[0005] One purpose of the utility model is to provide a battery pack, which can not only heat the battery core but also prevent the battery pack from thermal runaway.

[0006] Another object of the present invention is to provide an energy storage device that can both heat the battery cell and prevent the battery pack from thermal runaway.

[0007] To achieve this purpose, the utility model adopts the following technical solutions:

[0008] Battery pack, including:

[0009] A battery assembly, comprising a plurality of cells arranged in an array;

[0010] A heating element, disposed on at least one side of the battery assembly along its height direction;

[0011] The heat absorption component is arranged between the battery cells and in contact with the battery cells. The heat absorption component includes a packaging component and a phase change material. The packaging component is coated on the outside of the phase change material.

[0012] As an optional solution, the packaging component is tightly attached to the phase change material through vacuum adsorption.

[0013] As an optional solution, the phase change material is hydrogel.

[0014] As an optional solution, the packaging component is an aluminum-plastic film.

[0015] As an optional solution, the battery assembly includes multiple rows of battery cell rows, which are arranged side by side along the length direction of the battery assembly, each row of the battery cell rows includes multiple battery cells arranged along the width direction of the battery assembly, and the odd-numbered rows of the battery cell rows are wrapped with the heat absorption assembly.

[0016] As an optional solution, the heat absorption component includes a U-shaped portion, a first arc-shaped portion and a second arc-shaped portion, the first arc-shaped portion and the second arc-shaped portion are respectively connected to the two free ends of the U-shaped portion and have the same bending direction, the U-shaped portion is wrapped around the outside of a row of battery cells, the first arc-shaped portion is attached to the outside of the battery cells at the end of the battery cell row, and the second arc-shaped portion is attached to the outside of the battery cells at the end of another adjacent battery cell row.

[0017] As an optional solution, along the axial direction of the battery core, the height of the phase change material is 60%-80% of the height of the battery core.

[0018] As an optional solution, the packaging component and the battery core are fixed by gluing.

[0019] As an optional solution, the battery assembly also includes a bus, which is electrically connected to the multiple battery cells to connect the multiple battery cells in series or in parallel. The heating element is a heating film, and the resistance wire area of ​​the heating film corresponds to the position of the bus.

[0020] Energy storage equipment, including the above-mentioned battery pack.

[0021] Beneficial effects of the utility model:

[0022] The utility model provides a battery pack, which can ensure that the battery pack works normally at a suitable temperature by heating multiple battery cells through a heating element in a low temperature environment, and the heating element cooperates with a heat-absorbing component to achieve uniform heating and reduce the risk of thermal runaway. When a large amount of heat is generated inside the battery cell, due to the contact between the heat-absorbing component and the battery cell, the phase change material will absorb the heat and undergo a physical state change, quickly and efficiently taking away the large amount of heat generated inside the battery cell, reducing the temperature of the battery cell, effectively suppressing the thermal runaway of the battery pack, and improving the stability and safety of the battery pack.

[0023] The utility model also provides an energy storage device, which, by providing the above-mentioned battery pack, can heat multiple battery cells in a low temperature environment to ensure the normal operation of the battery pack, and can effectively suppress thermal runaway of the battery pack to improve the stability and safety of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the battery pack provided by the utility model;

[0025] Figure 2 It is an exploded view of the battery pack provided by the present utility model after hiding the heating element;

[0026] Figure 3 It is an exploded view of the battery pack provided by the present utility model;

[0027] Figure 4 It is an exploded view of the heat absorption component provided by the present utility model;

[0028] Figure 5 It is a partial structural schematic diagram of the battery pack provided by the present utility model;

[0029] Figure 6 It is a structural schematic diagram of the heat absorption component provided by the present utility model;

[0030] Figure 7 It is a matching schematic diagram of the heat absorption component and the battery cell provided by the present utility model.

[0031] In the figure:

[0032] 10. Battery assembly; 11. Battery cell row; 111. Battery cell; 12. Upper bracket; 121. Positioning hole; 13. Lower bracket; 14. Bus bar; 15. Acquisition board; 16. BMS board;

[0033] 20. Heating element; 21. Resistance wire area;

[0034] 30. Heat absorption component; 31. Encapsulation; 32. Phase change material; 33. U-shaped part; 34. First arc part; 35. Second arc part. Specific implementation manners

[0035] The present utility model will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present utility model, rather than limiting the present utility model. Additionally, it should be noted that for the sake of description, only parts related to the present utility model rather than all structures are shown in the drawings.

[0036] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; 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 internal communication of two components or the interaction relationship between two components. 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.

[0037] In the present utility model, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over" and "on the top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "under" and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0038] In the description of this embodiment, the orientation or positional relationships such as "upper", "lower", "right", etc. are based on the orientation or positional relationship shown in the drawings. It is only for the convenience of description and simplifying the operation, 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. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0039] As Figure 1 and Figure 2 shown, this embodiment provides a battery pack, which includes a battery assembly 10, a heating element 20 and a heat absorption assembly 30. The battery assembly 10 includes a plurality of battery cells 111 arranged in an array. The heating element 20 is disposed on at least one side of the battery assembly 10 along its height direction and is used to heat the plurality of battery cells 111. The heat absorption assembly 30 is disposed between the battery cells 111 and in contact with the battery cells 111. As Figure 4 shown, the heat absorption assembly 30 includes a packaging member 31 and a phase change material 32. The packaging member 31 covers the phase change material 32, and the packaging member 31 is in contact with the battery cells 111. For the convenience of understanding, the height direction of the battery assembly 10 is defined as the Z-axis direction, the length direction of the battery assembly 10 is defined as the X-axis direction, and the width direction of the battery assembly 10 is defined as the Y-axis direction.

[0040] In a low-temperature environment, by heating the plurality of battery cells 111 through the heating element 20, it can ensure that the battery pack operates normally at a suitable temperature. Moreover, the heating element 20 cooperates with the heat absorption assembly 30 to achieve uniform heating and reduce the risk of thermal runaway. When a large amount of heat is generated inside the battery cells 111, since the heat absorption assembly 30 is in contact with the battery cells 111, the phase change material 32 will absorb this heat and undergo a phase change, quickly and efficiently taking away the large amount of heat generated inside the battery cells 111, reducing the temperature of the battery cells 111, effectively suppressing the thermal runaway of the battery pack, and improving the stability and safety of the battery pack.

[0041] In this embodiment, the phase change material 32 is a hydrogel. The hydrogel itself is relatively soft and can ensure close fitting on the surface of the battery cell 111. As the phase change material 32, the hydrogel is a general term for high molecular polymers with a high water content and certain shape and mechanical properties. The specific heat capacity and thermal conductivity of the hydrogel are quite equivalent to those of water, approximately 4.2 kJ / (kg*K) - 5.2 kJ / (kg*K). In an abnormal situation, when a large amount of heat is generated inside the battery cell 111, the hydrogel can quickly absorb this heat and reduce the temperature of the battery cell 111. As the temperature rises, when the temperature reaches the water loss point of the hydrogel, the hydrogel takes away heat through the evaporation of internal moisture and releases water molecules to prevent thermal runaway. When the temperature drops to the water return point of the hydrogel, the hydrogel absorbs moisture from the air. This phase change process can be repeated to effectively control the heat inside the battery cell 111.

[0042] The hydrogel has a high heat capacity and latent heat of vaporization. During the heat dissipation process, by utilizing the property of the high latent heat of the hydrogel, it can effectively absorb and store a large amount of heat, effectively preventing thermal runaway in the battery pack. Secondly, the hydrogel has good thermal stability and chemical stability, is not easy to decompose or deteriorate, and can ensure long-term reliability and stability. In addition, the hydrogel also has good biocompatibility and environmental friendliness, and will not cause harm to the human body or the environment.

[0043] In this embodiment, the encapsulation member 31 is an aluminum-plastic film. By sealing the hydrogel with the aluminum-plastic film, the insulation performance can be satisfied, enabling the hydrogel to be used inside the battery pack. The aluminum-plastic film wraps around the hydrogel and has a certain thermal conductivity. It fits on the outer surface of the battery cell 111 and has a certain heat equalization ability to ensure the temperature consistency of the battery pack. In other embodiments, the material of the encapsulation member 31 can also be selected from PI, PET, PP, or high molecular composite materials for sealing.

[0044] In an alternative embodiment, the encapsulation member 31 is closely attached to the phase change material 32 through vacuum adsorption. The purpose of vacuum pumping is to enable the hydrogel to better contact the aluminum-plastic film and prevent the occurrence of bubbles inside, which may affect the contact between the heat absorption component 30 and the battery cell 111. The aluminum-plastic film wraps around the hydrogel, leaving one side for vacuum pumping. The thickness of the aluminum-plastic film is generally between 0.07 mm and 0.2 mm. Since the hydrogel needs to be wrapped with the aluminum-plastic film and undergo vacuum treatment, the length of the hydrogel generally does not exceed 400 mm.

[0045] In this embodiment, as Figure 7As shown, the battery assembly 10 includes multiple rows of battery cell rows 11, which are arranged side by side along the length direction (X-axis direction) of the battery assembly 10. Each row of battery cell rows 11 includes multiple battery cells 111 arranged along the width direction (Y-axis direction) of the battery assembly 10. The battery cells 111 are specifically cylindrical battery cells. The odd-numbered rows of battery cell rows 11 are wrapped with a heat absorption component 30. The heat absorption component 30 formed by wrapping a water gel with an aluminum-plastic film is wrapped outside the battery cells 111, preventing the battery cells 111 from being impacted by the external temperature, and preventing heat leakage during the heating process, and can achieve uniform heating. The above setting can reduce the number of heat absorption components 30 used, save costs, and enable the side of each row of battery cell rows 11 to be in contact with the heat absorption component 30, meeting the heat dissipation requirements of each row of battery cell rows 11, effectively preventing the battery pack from thermal runaway, and making the temperature difference between multiple battery cells 111 smaller, improving the temperature consistency of the battery pack.

[0046] Specifically, as Figure 6 and Figure 7 shown, the heat absorption component 30 includes a U-shaped part 33, a first arc part 34, and a second arc part 35. The first arc part 34 and the second arc part 35 are respectively connected to two free ends of the U-shaped part 33 and have the same bending direction. The U-shaped part 33 is wrapped outside a row of battery cell rows 11. The first arc part 34 is attached to the outside of the battery cell 111 located at the end in this row of battery cell rows 11, and the second arc part 35 is attached to the outside of the battery cell 111 located at the end in another adjacent row of battery cell rows 11. Limited by the production process of the heat absorption component 30, the length of the water gel cannot be too long due to vacuum pumping. The above setting makes the length of the heat absorption component 30 not too long, reducing the production and assembly difficulty, and can also ensure that the side of each battery cell 111 can be fully in contact with the heat absorption component 30, meeting the heat dissipation requirements of each battery cell 111, effectively preventing the battery pack from thermal runaway, and making the temperature difference between multiple battery cells 111 smaller, improving the temperature consistency of the battery pack.

[0047] Exemplarily, in this embodiment, taking seven rows of battery cell rows 11 and five heat absorption components 30 as an example, the arrangement manner of the heat absorption components 30 will be described. Specifically, the two ends of the battery cell row 11 along the Y-axis direction are defined as the first end and the second end respectively, where the end close to the positive direction of the Y-axis is the second end, and the end close to the negative direction of the Y-axis is the first end. The two sides of the battery cell row 11 along the X-axis direction are defined as the first side and the second side respectively, where the side close to the positive direction of the X-axis is the second side, and the side close to the negative direction of the X-axis is the first side. Along the positive direction of the X-axis, a heat absorption component 30 is wrapped outside the first row of battery cell rows 11. The outer side surface of the U-shaped portion 33 of the heat absorption component 30 is simultaneously attached to the first side of the second row of battery cell rows 11. The first arc portion 34 of the heat absorption component 30 is attached to the side surface of the battery cell 111 at the first end in the first row of battery cell rows 11, and the second arc portion 35 is attached to the side surface of the battery cell 111 at the first end in the second row of battery cell rows 11; a heat absorption component 30 is wrapped outside the third row of battery cell rows 11. The outer side surface of the U-shaped portion 33 of the heat absorption component 30 is simultaneously attached to the second side of the second row of battery cell rows 11. The first arc portion 34 of the heat absorption component 30 is attached to the side surface of the battery cell 111 at the second end in the third row of battery cell rows 11, and the second arc portion 35 is attached to the side surface of the battery cell 111 at the second end in the second row of battery cell rows 11. The first heat absorption component 30 and the second heat absorption component 30 face in opposite directions, and so on. When the number of battery cell rows 11 is an odd number, referring to the seventh row of battery cell rows 11, the heat absorption component 30 on the last row of battery cell rows 11 can be set to half of the above heat absorption component 30, that is, the structure form of half of the U-shaped portion 33 plus the first arc portion 34.

[0048] In an optional embodiment, along the axial direction of the battery cell 111, the height of the phase change material 32 is 60%-80% of the height of the battery cell 111, and the phase change material 32 is located at the central position of the axial direction of the battery cell 111. With such a setting, it can ensure that the contact area between each battery cell 111 and the heat absorption component 30 is as large as possible, ensure the heat dissipation efficiency, and will not affect the installation of the battery cell 111.

[0049] In an optional embodiment, the encapsulation member 31 and the battery cell 111 are fixed by gluing. Specifically, one side of the aluminum-plastic film is attached to the surface of the battery cell 111 through a back adhesive, which can ensure the stable connection and sufficient contact between the heat absorption component 30 and the battery cell 111.

[0050] As Figure 1 、 Figure 2 and Figure 5 shown, the battery assembly 10 further includes an upper bracket 12 and a lower bracket 13. A plurality of positioning holes 121 are provided in the upper bracket 12 and the lower bracket 13. The battery cells 111 are accommodated in the corresponding positioning holes 121 for positioning the battery cells 111. After the upper bracket 12 and the lower bracket 13 are buckled, they are connected by screws to fix the plurality of battery cells 111.

[0051] As shown Figure 3 in the figure, the battery assembly 10 further includes two busbars 14, two acquisition boards 15 and a BMS board 16. The two busbars 14 are respectively arranged on the opposite sides of the upper bracket 12 and the lower bracket 13, and are respectively electrically connected to a plurality of battery cells 111 to connect the plurality of battery cells 111 in series or in parallel to achieve the required capacity. The busbar 14 is composed of a plurality of aluminum bars. The two acquisition boards 15 are respectively electrically connected to the corresponding busbars 14 to acquire parameters such as the temperature, voltage, and current of the battery cells 111. The BMS board 16 is electrically connected to the acquisition board 15 at the bottom to control the charging and discharging of the battery pack and heating protection, etc.

[0052] In this embodiment, as Figure 3 shown in the figure, heating elements 20 are arranged on the outer sides of the busbars 14 on both the upper and lower sides. Among them, the heating element 20 is a heating film, and the resistance wire area 21 of the heating film corresponds to the positions of the respective aluminum bars of the busbar 14. The aluminum bars are heated by the heating film, thereby heating the battery cells 111 to ensure that the battery pack can also work normally at low temperatures.

[0053] This embodiment also provides an energy storage device, specifically a portable mobile energy storage power supply. The energy storage device includes a housing and the above-mentioned battery pack. The battery pack is arranged in the housing. Among them, the specific structure and working principle of the energy storage device belong to the prior art and will not be elaborated here.

[0054] For the energy storage device provided in this embodiment, by arranging the above-mentioned battery pack, in a low-temperature environment, the heating element 20 is used to heat a plurality of battery cells 111, which can ensure that the battery pack works normally at a suitable temperature. Moreover, the heating element 20 cooperates with the heat absorption component 30 to achieve uniform heating and reduce the risk of thermal runaway. When a large amount of heat is generated inside the battery cell 111, the heat absorption component 30 contacts the battery cell 111, and the phase change material 32 will absorb this heat and undergo a phase change, quickly and efficiently taking away the large amount of heat generated inside the battery cell 111, reducing the temperature of the battery cell 111, effectively suppressing the thermal runaway of the battery pack, and improving the stability and safety of the battery pack.

[0055] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly explaining the present invention, and are not limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments, and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. Battery pack, characterized in that, Comprising: a battery assembly including a plurality of battery cells arranged in an array; a heating member disposed on at least one side of the battery assembly along its height direction; a heat absorption assembly disposed between the battery cells and in contact with the battery cells, the heat absorption assembly including a packaging member and a phase change material, the packaging member covering the phase change material; 2. The battery pack according to claim 1, wherein, The packaging member is tightly attached to the phase change material by vacuum adsorption.

3. The battery pack according to claim 1, characterized in that, The phase change material is a hydrogel.

4. The battery pack according to claim 1, wherein The packaging member is an aluminum-plastic film.

5. The battery pack according to claim 1, characterized in that, The battery assembly includes multiple rows of battery cell rows, the multiple rows of battery cell rows being arranged side by side along the length direction of the battery assembly, each row of battery cell rows including a plurality of the battery cells arranged along the width direction of the battery assembly, and the odd-numbered rows of battery cell rows are wrapped with the heat absorption assembly.

6. The battery pack according to claim 5, characterized in that, The heat absorption assembly includes a U-shaped portion, a first arc-shaped portion, and a second arc-shaped portion. The first arc-shaped portion and the second arc-shaped portion are respectively connected to two free ends of the U-shaped portion and have the same bending direction. The U-shaped portion wraps around one row of battery cell rows, the first arc-shaped portion is attached to the battery cells at the ends in this row of battery cell rows, and the second arc-shaped portion is attached to the battery cells at the ends in another adjacent row of battery cell rows.

7. The battery pack according to any one of claims 1-6, characterized in that, Along the axial direction of the battery cell, the height of the phase change material is 60%-80% of the height of the battery cell.

8. The battery pack according to any one of claims 1-6, characterized in that, The packaging member is fixedly attached to the battery cell by gluing.

9. The battery pack according to any one of claims 1-6, characterized in that, The battery assembly further includes a bus bar, the bus bar being electrically connected to a plurality of the battery cells to connect the plurality of battery cells in series or in parallel, the heating member being a heating film, and the resistance wire area of the heating film corresponding to the position of the bus bar.

10. Energy storage device, characterized in that, Including the battery pack according to any one of claims 1-9.

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