Separator plate, battery cell and battery pack

Abstract

Separating plate (001), characterized in that the separating plate (001) comprises: a housing (011) with an inner cavity (012); a phase change substance (013) which is provided in the inner cavity (012).

Description

Technical field

[0001] This application relates to the field of battery technology, in particular to a separator plate, a battery cell and a battery pack. State of the art

[0002] In related technologies, the battery cell comprises a casing and a cell pack arranged inside the casing. The cell pack is manufactured by sequentially stacking or winding pole pieces and separators. To increase the energy density of battery cells and meet high-voltage application requirements, multiple cell packs are typically arranged within the casing. To prevent short circuits caused by contact between adjacent cell packs, a separator is placed between them to isolate them from one another.

[0003] However, the existing separating plates have a single function and can only meet the insulation requirements of the battery cell's cell packs. Disclosure of registration

[0004] The embodiments of the present application provide a separator plate, a battery cell and a battery pack, thereby improving the problem of a single function of the separator plate.

[0005] In the first aspect, the embodiment of the present application provides a separating plate, wherein the separating plate comprises: a housing with an inner cavity; and a phase change material provided in the inner cavity.

[0006] In one embodiment, the housing has an elasticity and the phase change substance becomes a fluid through heat absorption.

[0007] In one embodiment, the inner cavity comprises a first inner cavity and a second inner cavity, which are independent of each other, wherein the phase change substance is provided in the first inner cavity, wherein the first inner cavity and the second inner cavity are arranged sequentially from a center of the separating plate towards the periphery of the separating plate.

[0008] In one embodiment, the second inner cavity is filled with an inert gas and / or the second inner cavity is an annular cavity arranged around the first inner cavity.

[0009] In one embodiment, the housing comprises a first housing wall and a second housing wall that are opposite each other; wherein the first housing wall and the second housing wall are connected to each other to form the inner cavity, wherein the parts of the first housing wall and the second housing wall that are opposite each other are connected to each other to divide the inner cavity into the first inner cavity and the second inner cavity.

[0010] In one embodiment, a hot-pressed molded part is provided on the housing, and the hot-pressed molded part divides the inner cavity into the first inner cavity and the second inner cavity.

[0011] In one embodiment, the hot-pressed molded part is a pressure edge that divides the inner cavity into the first inner cavity and the second inner cavity, which are independent of each other.

[0012] In one embodiment, the phase change material comprises a solid-liquid phase change material.

[0013] In one embodiment, the housing is an airbag.

[0014] In the second aspect, the embodiment of the present application provides a battery cell. The battery cell comprises: a shell with a receiving cavity; several cell packs arranged sequentially at intervals within the receiving cavity; a aforementioned separating plate, wherein the separating plate is arranged between adjacent two cell packs, with a pair of opposing side walls of the housing each being in contact with the two cell packs adjacent to them, and / or a separating plate is arranged between the cell pack and the shell.

[0015] In one embodiment, the separating plate is provided on the inner wall of the shell.

[0016] In the third aspect, the embodiment of the present application further provides a battery pack. The battery pack comprises one of the aforementioned battery cells.

[0017] In one embodiment, the battery pack further comprises a box, a collection component, a battery management system, and a liquid cooling plate.

[0018] In one embodiment, the battery cell, the collection component, the battery management system and the liquid cooling plate are arranged inside the box.

[0019] In one embodiment, several battery cells are connected in series or parallel by the collecting component.

[0020] The advantageous effects of the embodiments of the present application are:

[0021] In the embodiments of the present application, the separating plate, by providing the inner cavity on the separating plate and the phase-change material in the inner cavity, not only serves to insulate the cell pack, but also has a cooling effect, which is realized by heat absorption from the cell pack by the heat-absorbing and phase-changing phase-change material. Thus, several functions are integrated in one separating plate. Brief description of the drawings

[0022] To provide a clearer explanation of the technical solutions in the embodiments of the present application, a brief introduction to the drawings necessary for describing these embodiments is given. It is evident that the drawings described below represent only some embodiments of the present application. A person skilled in the relevant technical field can derive other drawings from these drawings without any creative effort. Fig. 1 is a main view of a separating plate according to the embodiments of the present application; Fig. 2 is a sectional view along AA in Fig. 1; Fig. Figure 3 is a side view of a separating plate according to the embodiments of the present application; Fig. 4 is a sectional view along BB in Fig. 3; Fig. Figure 5 is a schematic view of the positions of a separator plate and a cell pack according to the embodiments of the present application. Reference symbol:

[0023] 001-Separator plate; 011-Housing; 111-Hot-pressed part; 012-Inner cavity; 121-First inner cavity; 122-Second inner cavity; 013-Phase change substance; 002 cell pack. Detailed descriptions

[0024] Please refer to Fig. Figure 1, which shows a main view of a separating plate 001 according to the embodiments of the present application. The embodiments of the present application provide a separating plate 001. The separating plate 001 comprises a housing 011 and a phase-change material 013. The housing 011 has an inner cavity 012. The phase-change material 013 is provided in the inner cavity 012.

[0025] It can be understood that the phase change material 013, also known as a phase change energy storage material, is a substance that transitions from one state to another through temperature changes, accompanied by heat absorption or release phenomena. Furthermore, the casing 011 consists of insulating material.

[0026] For example, phase change material 013 comprises one or more of the following phase change materials: solid-solid phase change material, solid-liquid phase change material, liquid-liquid phase change material, liquid-gas phase change material, solid-gas phase change material. Optionally, phase change material 013 comprises a solid-liquid phase change material. In particular, the solid-liquid phase change materials include an organic solid-liquid phase change material and an inorganic solid-liquid phase change material. The solid-liquid phase change material can be selected from aqueous compounds such as lithium nitrate trihydrate, calcium chloride crystal hydrate, Sodium sulfate crystal hydrate Sodium carbonate crystal hydrate, etc. It can also be selected from organic solid-liquid phase change materials such as paraffin, for example, aliphatic hydrocarbons, polyester polyol, and polyvinyl alcohol, etc. It can also be an organic solid-solid phase change material such as pentaerythritol, neopentyl glycol, for example, polyols and polymers. It is also possible to add one or more materials with high thermal conductivity, such as graphite, carbon fiber, foam metal, nano-oxide, nanometal particles, nanometal oxide particles, and metal shavings, to the phase change materials to increase the thermal conductivity of phase change material 013, thereby improving the overall heating uniformity of phase change material 013 and thus increasing the phase change uniformity of phase change material 013.As a result, the stress uniformity of surfaces in contact with the separating plate 001 of the cell packs on both sides of the separating plate 001 can be improved.

[0027] Furthermore, the doping ratio of all substances in the phase change material 013 can be adjusted according to the heating conditions and operating environment of different battery cells to achieve gradient heat dissipation at room temperature and elevated temperatures. This not only meets the heat dissipation requirements of the battery cells but also balances the heat dissipation effect of the separator plate 001 on the battery cells with the cost, thus avoiding the high cost of the separator plate 001. For example, if the typical operating temperature of a battery cell is 35-40°C and the maximum operating temperature of the battery cell is 60°C, the phase change temperature of the phase change material 013 can be set to 35-40°C and 50-55°C, with the phase change material operating more at 55°C.

[0028] In this embodiment, the separating plate 001, by providing an inner cavity 012 on the separating plate 001 and a phase-change material 013 in the inner cavity 012, not only insulates the cell pack but also has a cooling effect, which is achieved by heat absorption from the cell pack by the heat-absorbing and phase-changing phase-change material 013. Thus, several functions are integrated into one separating plate. In this way, the separating plate can insulate the cell pack and improve the heat dissipation efficiency of the cell pack, thereby increasing the reliability of the battery cell without affecting the energy density of the battery cell, despite the space it occupies.

[0029] In one embodiment, the housing 011 has elasticity, and the phase change material 013 becomes liquid after absorbing heat.

[0030] It can be understood that during operation of the battery cell, the cell pack undergoes thermal expansion and thereby presses against the separating plate 001.

[0031] Based on this, in this embodiment, the above settings allow the phase change material 013 to flow from the area where the separator plate 001 is most strongly pressed by the cell pack to other areas when the cell pack expands. This enables the separator plate 001 to provide buffering and space for the expansion of the cell pack. Therefore, damage to the cell pack can be avoided when the expansion force is large but the expansion space is small. Furthermore, the stress state of the separator plate 001 can be improved, thereby increasing its reliability.

[0032] See Fig. 2, a sectional view along AA in Fig. Figure 1 is shown. In one embodiment, the inner cavity 012 comprises a first inner cavity 121 and a second inner cavity 122, which are independent of each other. The phase change substance 013 is provided in the first inner cavity 121. The first inner cavity 121 and the second inner cavity 122 are arranged sequentially from the center of the separating plate 001 towards the periphery of the separating plate 001.

[0033] It can be understood that a separating structure is provided between the first inner cavity 121 and the second inner cavity 122 in order to divide the inner cavity 012 into a first inner cavity 121 and a second inner cavity 122. The minimum strength of the outer surface of the separating plate 001 is greater than the strength of the separating structure between the first inner cavity 121 and the second inner cavity 122.

[0034] As the cell pack expands, it pushes against the separator plate 001, subjecting the separator plate 001 to greater pressure, which can easily lead to the rupture of the inner cavity 012, causing the phase change substance 013 to flow out of the housing 011 and contaminate the electrolyte.

[0035] Based on this, in this embodiment, by providing the inner cavity 012 as the first inner cavity 121 and the second inner cavity 122, which are independent of each other, the separation structure between the first inner cavity 121 and the second inner cavity 122 can be broken when the first inner cavity 121 is under high pressure and the phase change substance 013 flows from the first inner cavity 121 into the second inner cavity 122. This avoids the situation in which the separating plate 001 is directly broken, and the phase change substance 013 flows outside the separating plate 001 and contaminates the electrolyte.

[0036] In one embodiment, the second inner cavity 122 is filled with inert gas such as helium and argon.

[0037] Due to the requirement for a specific thickness of the separating plate 001, adjacent two cell packs can be isolated. Therefore, in this embodiment, the inert gas is filled into the second inner cavity 122, so that if the thickness of the separating plate 001, which forms the wall surface of the second inner cavity 122, is small, the separating plate 001 can have a specific thickness at the second inner cavity 122 based on the inert gas. This prevents the distance between adjacent two battery cells at the second inner cavity 122 from being too small, thereby increasing the reliability of the battery cells.

[0038] Furthermore, if the separating plate 001 is subjected to pressure, thereby breaking up the separation structure between the first inner cavity 121 and the second inner cavity 122, the inert gas can also buffer the phase change substance 013, which falls into the second inner cavity 122, thereby reducing an impact force on the second inner cavity 122 and increasing the reliability of the separating plate 001.

[0039] See Fig. 3 and Fig. 4. Fig. Figure 3 is a side view of the separating plate 001 according to the embodiments of the present application, and Fig. 4 is a sectional view along BB in Fig. 3. In one embodiment, the second inner cavity 122 is an annular cavity arranged around the first inner cavity 121.

[0040] In this embodiment, the circumference of the first inner cavity 121 is enveloped by the second inner cavity 122 by the above setting, so that the phase change substance 013 can flow from any position on the circumference of the first inner cavity 121 into the second inner cavity 122. This adapts the layout structure of the first inner cavity 121 and the second inner cavity 122 to situations where the pressure position of the separating plate 001 and the flow direction of the phase change substance are uncertain. Thus, the adaptability of the separating plate 001 to different expansion states of the cell pack can be increased.

[0041] See Fig. 2, in one embodiment, the housing 011 comprises a first housing wall and a second housing wall. The first housing wall and the second housing wall are connected to each other to form the inner cavity 012, and the parts of the first housing wall and the second housing wall that are opposite each other are connected to each other to divide the inner cavity 012 into a first inner cavity 121 and a second inner cavity 122.

[0042] For example, the first housing wall is bonded to the second housing wall. Specifically, the first housing wall is joined to the second housing wall using ultrasonic hot pressing technology to form a hot-pressed molded part 111 on the housing 011. The hot-pressed molded part 111 divides the inner cavity 012 into a first inner cavity 121 and a second inner cavity 122.

[0043] It can be understood that the hot-pressed molded part 111 is a pressure edge that divides the inner cavity 012 into the first inner cavity 121 and the second inner cavity 122, which are independent of each other.

[0044] In this embodiment, the first inner cavity 121 and the second inner cavity 122 are formed in the manner described above, making the partition plate 001 simple in structure and easy to form, thus increasing the production efficiency of the partition plate 001 and reducing the manufacturing costs of the partition plate 001.

[0045] In one embodiment, the housing 011 is an airbag, and the airbag material is a thermoplastic polymer material, in particular a thermoplastic polymer material film with insulation that is not easily punctured, such as polypropylene, phenolic resin and their modified substances.

[0046] In this embodiment, positioning the housing 011 as airbags can reduce the space occupied by the housing 011 on the separating plate 001 of limited size, thereby increasing the amount of the phase change material 013 and increasing the heat dissipation effect of the separating plate 001 on the cell pack.

[0047] Furthermore, thermoplastic polymer materials are used for the housing 011, and the strength and deformation requirements for pressing the separating plate 001 can be met during multiple expansions of the cell package, and the housing is reusable.

[0048] The forming method of the separating plate 001 mainly comprises the following: manufacturing a capsule from the film and forming a hot-press molded part 111 onto the housing 011 using ultrasonic hot-pressing technology, wherein the hot-press molded part 111 divides the inner cavity 012 of the capsule into a first inner cavity 121 and a second inner cavity 122. The outer wall of the capsule is provided with a first through-hole that communicates with the first inner cavity 121 and with a second through-hole that communicates with the second inner cavity 122. The phase-change material 013 is filled into the first inner cavity 121 through the first through-hole. After filling, the first through-hole is sealed by hot melting or hot pressing, etc.The inert gas is filled into the second inner cavity 122 through the second through-hole, and the second through-hole is sealed in an environment that has a certain pressure and is filled with the inert gas.

[0049] Accordingly, the embodiments of the present application provide a battery cell comprising a shell, a cell pack 002, and the aforementioned separator plate 001. The shell has a receiving cavity. Several cell packs 002 are present. Several cell packs 002 are arranged sequentially at intervals within the receiving cavity. The separator plate 001 is positioned between two adjacent cell packs 002. A pair of opposing side walls of the housing 011 is each in contact with two adjacent cell packs 002.

[0050] It can be understood that a large area of ​​cell package 002 is in contact with separating plate 001. As in Fig.Figure 4 shows a schematic diagram of the positions of the separating plate 001 and the cell package 002 according to the embodiments of the present application.

[0051] In this embodiment, by using the aforementioned separating plate 001, on the one hand, two adjacent cell packs 002 can be isolated; on the other hand, the heat of the cell pack 002 can be absorbed by the heat-absorbing and phase-changing properties of the phase-change material 013 within the separating plate 001, thereby improving the heat dissipation efficiency of the battery cell and further increasing the reliability of the battery cell.

[0052] Several cell packs 002 are arranged sequentially at intervals along the first direction. In the first direction, the thickness of the separator plate 001 is "d", and the thickness of the battery cell is "D", where 1.5%D ≤ d ≤ 2.5%D. It can be understood that "d" includes, but is not limited to, 1.5%D, 1.6%D, 1.8%D, 2.0%D, 2.1%D, 2.4%D, and 2.5%D. An insufficient thickness of the separator plate 001 can lead to poor insulation of the separator plate 001 on the cell pack 002. An excessive thickness of the separator plate 001 can adversely affect the energy density of the battery cell.

[0053] In one embodiment, a separating plate 001 is provided between the cell package 002 and the shell.

[0054] It can be understood that the multiple cell packages 002 can be bound together by the separating plate, or that the separating plate can be attached directly to the cell packages 002 or can be provided on the inner wall of the shell.

[0055] In this embodiment, with the above settings, the cell pack 002 can be isolated from the shell by the separating plate 001, and the cell pack 002 can also be supported, while the heat dissipation performance of the battery cell is also increased.

[0056] Accordingly, the embodiments of the present application also provide for a battery pack comprising the aforementioned battery cell.

[0057] It can be understood that the battery pack further comprises components such as the housing, the collector, the battery management system, the liquid cooling plate, etc. The battery cell, the collector, the battery management system, and the liquid cooling plate are arranged inside the housing. Multiple battery cells are connected in series or parallel via the collector.

[0058] In this embodiment, the heat of the battery pack 002 can be absorbed by the heat-absorbing and phase-changing properties of the phase-change material 013 in the separating plate 001, thereby improving the heat dissipation efficiency of the battery pack and increasing the reliability of the battery pack.

[0059] The embodiments of the present application are introduced in detail above. Specific examples are used in this application to describe the principles and embodiments of the present application. The description of the embodiments above is intended only to aid in understanding the method and core ideas of the present application. Meanwhile, for a person skilled in the art in the relevant technical field, modifications to the specific embodiments and the scope of application may occur based on the ideas of this application. In conclusion, the content of this description should not be understood as limiting this application.

Claims

[1] Separation plate (001), characterized by that the separating plate (001) includes: a housing (011) with an internal cavity (012); a phase change substance (013) provided in the inner cavity (012). [2] Separating plate (001) according to claim 1, characterized by that the housing (011) has elasticity and the phase change material (013) becomes a fluid through heat absorption. [3] Separating plate (001) according to claim 1 or 2, characterized by in that the inner cavity (012) comprises a first inner cavity (121) and a second inner cavity (122) which are independent of one another, wherein the phase change substance (013) is provided in the first inner cavity (121), wherein the first inner cavity (121) and the second inner cavity (122) are arranged sequentially from a center of the separating plate (001) towards the periphery of the separating plate (001). [4] Separating plate (001) according to claim 3, characterized bythat the second inner cavity (122) is filled with an inert gas and / or the second inner cavity (122) is an annular cavity arranged around the first inner cavity (121). [5] Separating plate (001) according to claim 3 or 4, characterized by in that the housing (011) comprises a first housing wall and a second housing wall; wherein the first housing wall and the second housing wall are connected to one another to form the internal cavity (012), wherein the parts of the first housing wall and the second housing wall that are opposite one another are connected to one another to divide the internal cavity (012) into the first internal cavity (121) and the second internal cavity (122). [6] Separating plate (001) according to one of claims 3 to 5, characterized by that a hot-press molded part (111) is provided on the housing (011) and the hot-press molded part (111) divides the inner cavity (012) into the first inner cavity (121) and the second inner cavity (122). [7] Separating plate (001) according to claim 6, characterized by that the hot-press mold part (111) is a pressure edge which divides the inner cavity (012) into the first inner cavity (121) and the second inner cavity (122), which are independent of each other. [8] Separating plate (001) according to one of claims 1 to 7, characterized by that the phase change material (013) comprises a solid-liquid phase change material. [9] Separating plate (001) according to one of claims 1 to 8, characterized by that the housing (011) is an airbag. [10] Battery cell, characterized by that the battery cell includes: a shell with a receiving cavity; a plurality of cell packs (002) arranged sequentially at intervals in the receiving cavity; a separating plate (001) according to one of claims 1-9; wherein the separating plate (001) is arranged between adjacent two cell packs (002), wherein a pair of opposite side walls of the housing (011) is in contact with the two cell packs (002) adjacent thereto, and / or the separating plate (001) is arranged between the cell pack (002) and the shell. [11] Battery cell according to claim 10, characterized by that the separating plate (001) is provided on an inner wall of the shell. [12] Battery pack, characterized by that the battery pack comprises a battery cell according to claim 10 or 11. [13] Battery pack according to claim 12, characterized by that the battery pack further comprises a box, a collection component, a battery management system, a liquid cooling plate. [14] Battery pack according to claim 13, characterized by that the battery cell, the collection component, the battery management system and the liquid cooling plate are arranged inside the box. [15] Battery pack according to claim 13 or 14, characterized by that several battery cells are connected in series or parallel by the collecting component.

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