Battery cell modeling method and device in immersed energy storage system and temperature determination method

Abstract

The invention discloses a battery cell modeling method and device in an immersed energy storage system and a temperature determination method, and the method comprises the steps: dividing a battery cell into at least two grid blocks in the length direction, the width direction and the height direction of the battery cell, enabling the battery cell to carry out the heat transfer in the length direction, the width direction and the height direction in a battery cell model, and enabling the temperature of the battery cell to be determined. And the heat transfer form of the battery cell in the immersed energy storage system is better met. According to different positions of grid blocks, a three-dimensional heat conduction equation of a battery cell is discretized according to conditions, discrete equations corresponding to the grid blocks are obtained, the discrete equations comprise temperature relations between the grid blocks and adjacent structures, and then temperature relation equations between the grid blocks and the adjacent structures are built; and the modeling of the battery cell in the immersed energy storage system is realized. Moreover, the situation that the adjacent structures of the grid blocks located at the edge position comprise solid parts or immersion liquid is considered, the accuracy of the discrete equation is guaranteed, and the temperature distribution better conforming to reality is obtained according to the discrete equation.

Description

Technical Field

[0001] The present invention relates to the technical field of battery heat dissipation, and in particular to a battery cell modeling method, device, and temperature determination method in an immersion energy storage system. Background Art

[0002] With the development of the battery cell industry, the heat density of battery cells has also increased. Cooling solutions using air cooling and liquid cooling plates can no longer meet the heat dissipation needs of large battery cells. Immersion liquid cooling, which immerses the battery cells in oil, can achieve higher heat dissipation efficiency.

[0003] In an immersion scenario, the direction of heat flow from the battery cell to the surrounding environment is not single. The existing modeling scheme that regards the battery cell as a mass point that conducts heat in a single direction is not applicable to immersion energy storage products. Summary of the Invention

[0004] The present invention provides a method, device and temperature determination method for battery cell modeling in an immersion energy storage system, so as to provide a more applicable model of the battery cell in the immersion energy storage system and thereby obtain a temperature distribution that is more in line with reality.

[0005] According to one aspect of the present invention, a method for modeling a battery cell in an immersion energy storage system is provided, comprising:

[0006] Dividing the battery cell into at least two grid blocks along the length, width and height directions of the battery cell respectively;

[0007] Obtain the three-dimensional heat conduction equation of the battery cell;

[0008] Based on the position of the grid blocks, the three-dimensional heat conduction equation of the battery cell is discretized to obtain a discrete equation corresponding to the grid block. The discrete equation includes the temperature relationship between the grid block and adjacent structures, and the adjacent structures include other grid blocks, solid components of the battery cell and at least one of the immersion fluid.

[0009] Optionally, the battery cell is divided into at least two grid blocks along the length direction, width direction and height direction of the battery cell, respectively, including:

[0010] Divide the battery cell equally into at least two grid blocks along the length, width and height directions of the battery cell respectively;

[0011] Alternatively, the battery cell is unequally divided into at least two grid blocks along at least one of the length direction, width direction and height direction of the battery cell.

[0012] Optionally, the at least two grid blocks include an edge grid block and an inner grid block; along at least one of the length direction, the width direction, and the height direction, the adjacent structures of the edge grid block are solid components or immersion liquid; along the length direction, the width direction, and the height direction, the adjacent structures of the inner grid block are all other grid blocks;

[0013] Based on the position of the grid block, the three-dimensional heat conduction equation of the battery cell is discretized to obtain the discrete equation corresponding to the grid block, including:

[0014] For the internal grid block, the three-dimensional heat conduction equation is spatially discretized to obtain the first discrete equation corresponding to the internal grid block. The first discrete equation includes the temperature of the internal grid block and its relationship with the temperatures of other adjacent grid blocks in the length, width, and height directions.

[0015] For the edge grid block, based on the adjacent structure of the edge grid block including the immersion liquid, a three-dimensional heat conduction equation is spatially discretized to obtain a second discrete equation corresponding to the edge grid block, the second discrete equation including the relationship between the temperature of the edge grid block, the temperature of the adjacent grid blocks in at least one of the length direction, the width direction, and the height direction, and the temperature of the immersion liquid;

[0016] For edge grid blocks, the three-dimensional heat conduction equation is spatially discretized based on the fact that the adjacent structure of the edge grid block includes solid components, thereby obtaining a third discrete equation corresponding to the edge grid block. The third discrete equation includes the temperature of the edge grid block and its relationship with the temperature of the adjacent grid blocks in at least one direction of the length, width and height directions, as well as the temperature of the solid components.

[0017] Optionally, based on the position of the grid blocks, the three-dimensional heat conduction equation of the battery cell is discretized to obtain the discrete equation corresponding to the grid blocks, including:

[0018] Based on the position of the grid block, the central difference format of the finite difference method is used to discretize the three-dimensional heat conduction equation of the battery cell and obtain the discrete equation corresponding to the grid block.

[0019] Optionally, the three-dimensional heat conduction equation is in the form of a three-dimensional transient heat source. The three-dimensional heat conduction equation is:

[0020]

[0021] Where, ρ represents the density of the battery cell; c represents the specific heat capacity of the battery cell; t represents temperature, τ represents time; λ x ,λ y ,λ z are the thermal conductivity in the length, width and height directions respectively; is the heating power density of the battery cell.

[0022] Optionally, along the length, width, and height directions of the battery cell, the battery cell is evenly divided into multiple grid blocks;

[0023] The first discrete equation is:

[0024]

[0025] where t ijk represents the temperature of Wijk, and Wijk represents the i-th grid block in the length direction, the j-th grid block in the width direction, and the k-th grid block in the height direction; where 2 ≤ i < m, m is the total number of grid blocks divided along the length direction, m ≥ 2; 2 ≤ j < n, n is the total number of grid blocks divided along the width direction, n ≥ 2; 2 ≤ k < p, p is the total number of grid blocks divided along the height direction, p ≥ 2; and i, j, k, m, n, and p are all positive integers;

[0026] t xi+1 represents the temperature of the next grid block of Wijk in the length direction, and t xi-1 represents the temperature of the previous grid block of Wijk in the length direction; t yj+1 represents the temperature of the next grid block of Wijk in the width direction, and t yj-1 represents the temperature of the previous grid block of Wijk in the width direction; t zk+1 represents the temperature of the next grid block of Wijk in the height direction, and t zk-1 represents the temperature of the previous grid block of Wijk in the height direction; Δx represents the size of the grid block in the length direction, Δy represents the size of the grid block in the width direction, and Δz represents the size of the grid block in the height direction;

[0027] When the adjacent structure of the edge grid block in the length direction includes the immersion liquid, the second discrete equation is

[0028]

[0029] Q fluid = h(t [[ID=3⑨]] fluid - t ijk )ΔyΔz;

[0030] where Q fluid represents the heat exchange amount between the immersion liquid and the battery cell, h represents the convective heat transfer coefficient, and t fluid represents the temperature of the immersion liquid; t xil represents the temperature of the adjacent grid block of the edge grid block in the length direction;

[0031] When the adjacent structure of the edge grid block in the width direction includes the immersion liquid, the second discrete equation is

[0032]

[0033] Q fluid =h(t fluid -t ijk )ΔxΔz;t yjl represents the temperature of the adjacent grid blocks of the edge grid block along the width direction;

[0034] In the height direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0035]

[0036] Q fluid =h(t fluid -t ijk )ΔxΔy;

[0037] t zkl represents the temperature of the adjacent grid blocks of the edge grid blocks along the height direction;

[0038] In the case where the adjacent structures of the edge grid blocks in the length direction include solid components, the third discretization equation is

[0039]

[0040] Where Δx' is equal to Δx and Δx s The average of λ' is equal to λ x and λ sx The average of Δx s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sx represents the thermal conductivity of a solid component along its length; t xs Represents the temperature of the solid component adjacent to the edge grid block in the length direction;

[0041] In the width direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0042]

[0043] Where Δy' is equal to Δy and Δy s The average of λ is equal to λ y and λ sy The average of Δy s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sy represents the thermal conductivity of a solid component along its length; t ys Represents the temperature of the solid components adjacent to the edge grid block in the width direction;

[0044] In the height direction, when the adjacent structure of the edge grid block includes a solid component, the third discrete equation is

[0045]

[0046] Δz' is equal to the average of Δz and Δz s and λ”' is equal to the average of λ z and λ sy . Δz s represents the dimension of the solid component adjacent to the edge grid block in the length direction; λ sz represents the thermal conductivity of the solid component in the length direction, and t zs represents the temperature of the solid component adjacent to the edge grid block in the height direction.

[0047] Optionally, along at least one of the length, width, and height directions of the battery cell, the dimensions of at least two grid blocks are not equal;

[0048] The first discrete equation is:

[0049]

[0050] where t ijk represents the temperature of Wijk, and Wijk represents the i-th grid block in the length direction, the j-th grid block in the width direction, and the k-th grid block in the height direction; Δx i , Δy j , and Δz k represent the dimensions of Wijk in the length, width, and height directions respectively; where 2 ≤ i < m, m is the total number of grid blocks divided in the length direction, m ≥ 2; 2 ≤ j < n, n is the total number of grid blocks divided in the width direction, n ≥ 2; 2 ≤ k < p, p is the total number of grid blocks divided in the height direction, p ≥ 2; and i, j, k, m, n, p are all positive integers;

[0051] t xi+1 represents the temperature of the next grid block of Wijk in the length direction, and t xi-1 represents the temperature of the previous grid block of Wijk in the length direction; t yj+1 represents the temperature of the next grid block of Wijk in the width direction, and t yj-1 represents the temperature of the previous grid block of Wijk in the width direction; t zk+1 represents the temperature of the next grid block of Wijk in the height direction, and t zk-1 represents the temperature of the previous grid block of Wijk in the height direction;

[0052] In the case where the adjacent structure of the edge grid block in the length direction includes the immersion liquid, the second discrete equation is

[0053]

[0054] Q fluid =h(t fluid -t ijk )Δy j Δz k ;

[0055] Among them, Q fluid represents the heat exchange between the immersion liquid and the battery cell, h represents the convection heat transfer coefficient, t fluid Indicates the immersion liquid temperature; t xil represents the temperature of the adjacent grid blocks along the length direction of the edge grid block; Δx il Indicates the size of the adjacent grid blocks along the length direction of the edge grid block;

[0056] In the width direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0057]

[0058] Q fluid =h(t fluid -t ijk )Δx i Δz k ;

[0059] t yjl represents the temperature of the adjacent grid blocks along the width direction of the edge grid block; Δy jl Indicates the size of the adjacent grid blocks along the length direction of the edge grid blocks along the width direction;

[0060] In the height direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0061]

[0062] Q fluid =h(t fluid -t ijk )Δx i Δy j ;

[0063] t zkl represents the temperature of the adjacent grid blocks along the height direction of the edge grid block; Δz kl Indicates the size of the adjacent grid blocks along the length direction of the edge grid block along the height direction;

[0064] In the case where the adjacent structures of the edge grid blocks in the length direction include solid components, the third discretization equation is

[0065]

[0066] Where Δx' is equal to Δx i and Δx s The average of λ' is equal to λ x and λ sx The average of Δx i represents the size of the edge grid block along the length direction, Δx s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sx represents the thermal conductivity of a solid component along its length; t xs Represents the temperature of the solid component adjacent to the edge grid block in the length direction;

[0067] In the width direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0068]

[0069] Where Δy' is equal to Δy j with Δy s The average of λ is equal to λ y and λ sy The average of Δy j represents the size of the edge grid block along the width direction, Δy s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sy represents the thermal conductivity of a solid component along its length; t ys Represents the temperature of the solid components adjacent to the edge grid block in the width direction;

[0070] In the height direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0071]

[0072] Δz' equals Δz k With Δz s The average of λ' is equal to λ z and λ sz The average value, Δz k represents the size of the edge grid block along the height direction, Δz s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sz represents the thermal conductivity of the solid component along the length direction, t zsRepresents the temperature of solid components adjacent to the edge mesh block in the height direction.

[0073] According to another aspect of the present invention, a method for determining the temperature of a battery cell in an immersion energy storage system is provided, comprising:

[0074] Obtaining a cell model, where the cell model includes discrete equations corresponding to the grid blocks into which the cell is divided, and the discrete equations are modeled using the cell modeling method for an immersion energy storage system in any embodiment of the present invention;

[0075] Determine the temperature corresponding to the grid block based on the battery cell model.

[0076] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0077] at least one processor; and

[0078] a memory communicatively connected to at least one processor; wherein,

[0079] The memory stores a computer program that can be executed by at least one processor. The computer program is executed by the at least one processor so that the at least one processor can execute the method for modeling a battery cell in an immersion energy storage system according to any embodiment of the present invention.

[0080] According to another aspect of the present invention, a computer-readable storage medium is provided, which stores computer instructions, and the computer instructions are used to enable a processor to implement the battery cell modeling method in an immersion energy storage system in any embodiment of the present invention when executed.

[0081] The battery cell modeling method, device and temperature determination method in the immersion energy storage system of the embodiment of the present invention divides the battery cell into at least two grid blocks along the length direction, width direction and height direction of the battery cell respectively, so that in the established battery cell model, the battery cell can transfer heat along the length direction, width direction and height direction, which is more in line with the heat transfer form of the battery cell in the immersion energy storage system. By obtaining the three-dimensional heat conduction equation of the battery cell, the three-dimensional heat conduction equation of the battery cell is discretized according to the different positions of the grid blocks, and the discrete equation corresponding to the grid block is obtained. The discrete equation includes the temperature relationship between the grid block and the adjacent structure. The adjacent structure includes at least one of the grid block, the solid components of the battery cell and the immersion liquid, and then the temperature relationship equation between the grid block and the adjacent structure is constructed to achieve modeling of the battery cell in the immersion energy storage system. In addition, the situation where the adjacent structure of the grid block located at the edge position includes solid components or immersion liquid is taken into account to ensure the accuracy of the obtained discrete equation, so that a temperature distribution that is more in line with reality can be obtained according to the discrete equation.

[0082] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0084] Figure 1 This is a flow chart of a method for modeling a battery cell in an immersion energy storage system provided by an embodiment of the present invention.

[0085] Figure 2 It is the front view of the battery cell;

[0086] Figure 3 It is a side view of the battery cell;

[0087] Figure 4 It is a top view of the battery cell;

[0088] Figure 5 This is a flow chart of another method for modeling a battery cell in an immersion energy storage system provided by an embodiment of the present invention;

[0089] Figure 6 This is a flow chart of another method for modeling a battery cell in an immersion energy storage system provided by an embodiment of the present invention;

[0090] Figure 7 This is a flow chart of a method for determining the temperature of a battery cell in an immersion energy storage system provided by an embodiment of the present invention;

[0091] Figure 8 It is a structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0092] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0093] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0094] The embodiment of the present invention provides a method for modeling a battery cell in an immersion energy storage system. Figure 1 This is a flow chart of a method for modeling a cell in an immersion energy storage system provided by an embodiment of the present invention. Figure 1 , the cell modeling method in the immersion energy storage system includes:

[0095] S110 , dividing the battery cell into at least two grid blocks along the length direction, width direction, and height direction of the battery cell respectively.

[0096] Specifically, in this step, the battery cell can be divided into at least two grid blocks according to the size of the battery cell. Optionally, the larger the size of the battery cell, the more grid blocks the battery cell is divided into. In this step, the battery cell is divided into at least two grid blocks along the length direction, width direction and height direction of the battery cell, respectively, so that in the established battery cell model, the battery cell can transfer heat along the length direction, width direction and height direction. Compared with the prior art, the battery cell is regarded as a mass point that conducts heat in a single direction. This is more in line with the heat transfer form of the battery cell in the immersion energy storage system and can improve the accuracy of the battery cell model.

[0097] In some embodiments, the battery cell is in the form of a rectangular parallelepiped, wherein each grid block corresponds to a portion of the battery cell structure, and at least two grid blocks are spliced ​​together to form the entire battery cell. Figure 2 This is the front view of the battery cell. Figure 3 This is a side view of the battery cell. Figure 4 This is a top view of the battery cell. Figure 2-Figure 4 Taking the example of dividing the battery cell into three grid blocks 20 along the length direction x0 of the battery cell, into four grid blocks 20 along the width direction y0 of the battery cell, and into two grid blocks along the height direction z0 of the battery cell, the battery cell is divided into 24 grid blocks 20.

[0098] S120. Obtain the three-dimensional heat conduction equation of the battery cell.

[0099] The three-dimensional heat conduction equation of the battery cell can be used to represent the temperature of the battery cell at each moment and each position. In some embodiments, the three-dimensional heat conduction equation of the battery cell is in the form of a three-dimensional transient internal heat source. Specifically, the three-dimensional heat conduction equation is as follows:

[0100]

[0101] Where ρ represents the density of the battery cell, for example, the unit can be m 3 / kg; c represents the specific heat capacity of the battery cell, for example, the unit can be J / (kg·K); t represents the temperature, for example, the unit can be K; τ represents the time, for example, the unit can be s; λ x ,λ y ,λ z Represents the thermal conductivity in the length direction, width direction, and height direction respectively, for example, the unit can be w / (m·K); Indicates the heating power density of the battery cell, for example, the unit can be w / m 3 In some embodiments, the heating power density of the battery cell is an instantaneous value, while in other embodiments, the heating power density of the battery cell is an average value. x, y, and z can represent the coordinate values ​​in the length direction, width direction, and height direction, respectively.

[0102] S130. Discretize the three-dimensional heat conduction equation of the battery cell based on the position of the grid block to obtain a discrete equation corresponding to the grid block, where the discrete equation includes a temperature relationship between the grid block and an adjacent structure, where the adjacent structure includes at least one of other grid blocks, solid components of the battery cell, and an immersion liquid.

[0103] That is, the adjacent structure of a grid block may be at least one of other grid blocks other than the grid block, solid components of the battery cell, and immersion liquid.

[0104] Optionally, the discrete equation includes the temperature relationship between the grid block and the adjacent structure at each moment. Specifically, the adjacent structures of the grid block may be different depending on the position of the grid block of the battery cell. Exemplarily, the adjacent structures of some grid blocks in all directions are grid blocks. Exemplarily, the adjacent structures of some grid blocks in the length direction are grid blocks, the adjacent structures in the width direction are grid blocks, and the adjacent structures in the height direction are also grid blocks. The adjacent structures of some grid blocks in at least one direction are solid parts, and the adjacent structures of some grid blocks in at least one direction are immersion liquids. Exemplarily, the adjacent structures of some grid blocks in the length direction are solid parts, and the adjacent structures of some grid blocks in the width direction are immersion liquids.

[0105] In some embodiments, the three-dimensional heat conduction equation of the battery cell may be discretized based on the position of the grid block using the central difference format of the finite difference method to obtain a discrete equation corresponding to the grid block.

[0106] In this step, the three-dimensional heat conduction equation of the battery cell is discretized according to the different positions of the grid blocks, and the discrete equation corresponding to the grid blocks is obtained. The temperature relationship equation between the grid blocks and the adjacent structures is constructed to realize the modeling of the battery cell in the immersion energy storage system.

[0107] The method for modeling the battery cell in the immersion energy storage system of this embodiment divides the battery cell into at least two grid blocks along the length, width and height directions of the battery cell, respectively, so that in the established battery cell model, the battery cell can transfer heat along the length, width and height directions, which is more in line with the heat transfer form of the battery cell in the immersion energy storage system. By obtaining the three-dimensional heat conduction equation of the battery cell, the three-dimensional heat conduction equation of the battery cell is discretized according to the different positions of the grid blocks, and the discrete equation corresponding to the grid block is obtained. The discrete equation includes the temperature relationship between the grid block and the adjacent structure. The adjacent structure includes at least one of the grid block, the solid components of the battery cell and the immersion liquid, and then the temperature relationship equation between the grid block and the adjacent structure is constructed to achieve the modeling of the battery cell in the immersion energy storage system. In addition, the situation where the adjacent structure of the grid block located at the edge position includes solid components or immersion liquid is taken into account to ensure the accuracy of the obtained discrete equation, so that a temperature distribution that is more in line with reality can be obtained according to the discrete equation.

[0108] Optionally, at least two grid blocks include an edge grid block and an internal grid block; along at least one of the length, width and height directions, the adjacent structures of the edge grid block are solid parts or immersion liquid; along the length, width and height directions, the adjacent structures of the internal grid block are all other grid blocks, that is, along the length, width and height directions, the adjacent structures of the internal grid block are other grid blocks except the internal grid block. Figure 5 This is a flowchart of another method for modeling a cell in an immersion energy storage system provided by an embodiment of the present invention. Figure 5 , the cell modeling method in the immersion energy storage system includes:

[0109] S210 , equally dividing the battery cell into at least two grid blocks along the length direction, width direction, and height direction of the battery cell.

[0110] Among them, along the length direction, width direction and height direction of the battery cell respectively, the battery cell is evenly divided into at least two grid blocks, and the sizes of each grid block in the length direction of the battery cell are equal, the sizes in the width direction of the battery cell are equal, and the sizes in the height direction of the battery cell are also equal. Optionally, along the length direction, width direction and height direction of the battery cell, the battery cell is evenly divided into multiple grid blocks. Taking a hypothetical battery cell as an example, its size is 340*60*200mm. Optionally, it can be divided into 10 blocks in the length direction, 6 blocks in the width direction, and 8 blocks in the height direction. Correspondingly, the size of the grid block in the length direction of the battery cell is 34mm, the size of the grid block in the width direction of the battery cell is 10mm, and the size of the grid block in the height direction of the battery cell is 25mm. By evenly dividing the battery cell into multiple grid blocks, the volume corresponding to each grid block is equal, making the subsequent modeling of the battery cell simpler, and thus reducing the complexity of calculating the temperature of the battery cell.

[0111] S220. Obtain the three-dimensional heat conduction equation of the battery cell.

[0112] S230. For the internal grid blocks, perform spatial discretization on the three-dimensional heat conduction equation to obtain the first discrete equation corresponding to the internal grid blocks. The first discrete equation includes the temperature of the internal grid blocks and the temperature relationships with other grid blocks adjacent in the length direction, width direction and height direction respectively.

[0113] Specifically, for the internal grid blocks, uniformly discretize the spatial variables of the three-dimensional conduction equation to obtain the first discrete equation corresponding to the internal grid blocks.

[0114] The first discrete equation is:

[0115]

[0116] where, t ijk represents the temperature of Wijk, and Wijk represents the i-th grid block in the length direction, the j-th grid block in the width direction, and the k-th grid block in the height direction; where, 2 ≤ i < m, m is the total number of grid blocks divided in the length direction, m ≥ 2; 2 ≤ j < n, n is the total number of grid blocks divided in the width direction, n ≥ 2; 2 ≤ k < p, p is the total number of grid blocks divided in the height direction, p ≥ 2; and i, j, k, m, n, p are all positive integers; <00,00493>

[0117] t xi+1 represents the temperature of the next grid block of Wijk in the length direction, t xi-1 represents the temperature of the previous grid block of Wijk in the length direction; t yj+1 represents the temperature of the next grid block of Wijk in the width direction, t yj-1 represents the temperature of the previous grid block of Wijk in the width direction; tzk+1 Indicates the temperature of the next grid block of Wijk in the height direction, t zk-1 Represents the temperature of the previous grid block of Wijk in the height direction; Δx represents the size of the grid block along the length direction, Δy represents the size of the grid block along the width direction, and Δz represents the size of the grid block along the height direction.

[0118] S240. For the edge grid block, based on the adjacent structure of the edge grid block including the immersion liquid, perform spatial discretization on the three-dimensional heat conduction equation to obtain a second discrete equation corresponding to the edge grid block, the second discrete equation including.

[0119] Specifically, for edge grid blocks whose adjacent structures include immersion fluid, the spatial variables of the three-dimensional conduction equation are uniformly discretized to obtain a second discrete equation corresponding to the edge grid block. The second discrete equation specifically includes the relationship between the temperature of the edge grid block, the temperature of adjacent grid blocks in at least one of the length, width, and height directions, and the temperature of the immersion fluid adjacent to the edge grid block.

[0120] In the case where the adjacent structure of the edge grid block in the length direction includes the immersion liquid, the second discrete equation is

[0121]

[0122] Q fluid =h(t fluid -t ijk )ΔyΔz;

[0123] Among them, Q fluid represents the heat exchange between the immersion liquid and the battery cell, h represents the convection heat transfer coefficient, t fluid Indicates the immersion liquid temperature; t xil Represents the temperature of the adjacent grid blocks along the length direction of the edge grid block.

[0124] For example, in the longitudinal direction, when the previous adjacent structure of the edge grid block is the immersion liquid and the next adjacent structure is the internal grid block, the second discrete equation is:

[0125]

[0126] In the width direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0127]

[0128] Q fluid =h(t fluid -t ijk )ΔxΔz;

[0129] tyjl Represents the temperature of the adjacent grid blocks along the width direction of the edge grid block.

[0130] For example, in the width direction, when the previous adjacent structure of the edge grid block is the immersion liquid and the next adjacent structure is the internal grid block, the second discrete equation is:

[0131]

[0132] In the height direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0133]

[0134] Q fluid =h(t fluid -t ijk )ΔxΔy;

[0135] t zkl Represents the temperature of the adjacent grid blocks along the height direction of the edge grid block.

[0136] For example, in the height direction, when the upper adjacent structure of the edge grid block is the immersion liquid and the lower adjacent structure is the internal grid block, the second discrete equation is:

[0137]

[0138] S250. For the edge grid block, based on the fact that the adjacent structure of the edge grid block includes solid components, the three-dimensional heat conduction equation is spatially discretized to obtain a third discrete equation corresponding to the edge grid block. The third discrete equation includes the temperature of the edge grid block and the relationship with the temperature of the grid blocks adjacent to it in at least one direction of the length direction, the width direction and the height direction, as well as the temperature of the solid components.

[0139] Specifically, for edge mesh blocks whose adjacent structures include solid components, the spatial variables of the three-dimensional conduction equation are uniformly discretized to obtain a third discrete equation corresponding to the edge mesh block. The third discrete equation includes the relationship between the temperature of the edge mesh block and the temperature of adjacent mesh blocks in at least one of the length, width, and height directions, as well as the temperature of the solid component adjacent to the edge mesh block.

[0140] In the case where the adjacent structures of the edge grid blocks in the length direction include solid components, the third discrete equation is

[0141]

[0142] Where Δx' is equal to Δx and Δx s The average of λ' is equal to λ x and λsx The average of Δx s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sx represents the thermal conductivity of a solid component along its length; t xs Represents the temperature of the solid component adjacent to the edge mesh block in the length direction.

[0143] Among them, Δx' can be equal to Δx and Δx s The arithmetic mean of λ can also be the harmonic mean. λ' can be equal to λ x and λ sx The arithmetic mean of can also be the harmonic mean. For example,

[0144] For example, in the longitudinal direction, when the previous adjacent structure of the edge grid block is a solid component and the next adjacent structure is an internal grid block, the third discrete equation is:

[0145]

[0146] In the width direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0147]

[0148] Where Δy' is equal to Δy and Δy s The average of λ is equal to λ y and λ sy The average of Δy s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sy represents the thermal conductivity of a solid component along its length; t ys Represents the temperature of solid components adjacent to the edge mesh block in the width direction.

[0149] Among them, Δy' can be equal to Δy and Δy s The arithmetic mean of λ can also be the harmonic mean. λ" can be equal to λ y and λ sy The arithmetic mean of can also be the harmonic mean. For example,

[0150] For example, in the width direction, when the previous adjacent structure of the edge grid block is a solid component and the next adjacent structure is an internal grid block, the third discrete equation is:

[0151]

[0152] In the height direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0153]

[0154] Δz' is equal to Δz and Δz s The average of λ' is equal to λ z and λ sy The average value, Δz s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sz represents the thermal conductivity of the solid component along the length direction, t zs Represents the temperature of solid components adjacent to the edge mesh block in the height direction.

[0155] Among them, Δz' can be equal to Δz and Δz s The arithmetic mean of λ can also be the harmonic mean. λ"' can be equal to λ z and λ sy The arithmetic mean of can also be the harmonic mean. For example,

[0156] For example, in the height direction, when the upper adjacent structure of the edge grid block is a solid component and the lower adjacent structure is an internal grid block, the third discrete equation is:

[0157]

[0158] Figure 8 This is a flowchart of another method for modeling a cell in an immersion energy storage system provided by an embodiment of the present invention. Figure 8 , the cell modeling method in the immersion energy storage system includes:

[0159] S310 , unequally dividing the battery cell into at least two grid blocks along at least one of a length direction, a width direction, and a height direction of the battery cell.

[0160] Specifically, when the battery cell is unevenly divided into at least two grid blocks along at least one of its length, width, and height, the sizes of at least two of the grid blocks along at least one of its length, width, and height are unequal. This division method is more applicable to irregularly shaped battery cells and can reduce numerical errors by locally increasing the grid density in areas with large temperature gradients. In areas with small temperature gradients, a sparse grid is used to reduce the total number of grid cells and the computational complexity.

[0161] S320. Obtain the three-dimensional heat conduction equation of the battery cell.

[0162] S330. For the internal grid blocks, perform spatial discretization on the three-dimensional heat conduction equation to obtain the first discrete equation corresponding to the internal grid blocks. The first discrete equation includes the temperature of the internal grid blocks and the temperature relationships with the grid blocks adjacent in the length, width, and height directions respectively.

[0163] Specifically, for the internal grid blocks, uniformly discretize the spatial variables of the three-dimensional conduction equation to obtain the first discrete equation corresponding to the internal grid blocks.

[0164] Among them, the first discrete equation is:

[0165]

[0166] Among them, t ijk represents the temperature of Wijk. Wijk represents the i-th grid block in the length direction, the j-th grid block in the width direction, and the k-th grid block in the height direction; Δx i , Δy j , Δz k represent the dimensions of Wijk in the length, width, and height directions respectively; where 2 ≤ i < m, m is the total number of grid blocks divided in the length direction, m ≥ 2; 2 ≤ j < n, n is the total number of grid blocks divided in the width direction, n ≥ 2; 2 ≤ k < p, p is the total number of grid blocks divided in the height direction, p ≥ 2; and i, j, k, m, n, p are all positive integers;

[0167] t xi+1 represents the temperature of the next grid block of Wijk in the length direction, t xi-1 represents the temperature of the previous grid block of Wijk in the length direction; t yj+1 represents the temperature of the next grid block of Wijk in the width direction, t yj-1 represents the temperature of the previous grid block of Wijk in the width direction; t zk+1 represents the temperature of the next grid block of Wijk in the height direction, t zk-1 represents the temperature of the previous grid block of Wijk in the height direction.

[0168] S340. For the edge grid blocks, according to the adjacent structure of the edge grid blocks including the immersion liquid, perform spatial discretization on the three-dimensional heat conduction equation to obtain the second discrete equation corresponding to the edge grid blocks. The second discrete equation includes the temperature of the edge grid blocks, the temperature relationships with the grid blocks adjacent in at least one of the length, width, and height directions, and the temperature of the immersion liquid.

[0169] Specifically, for the edge grid blocks with an adjacent structure including the immersion liquid, uniformly discretize the spatial variables of the three-dimensional conduction equation to obtain the second discrete equation corresponding to the edge grid blocks.

[0170] In the case where the adjacent structure of the edge grid block in the length direction includes the immersion liquid, the second discrete equation is

[0171]

[0172] Q fluid =h(t fluid -t ijk )Δy j Δz k ;

[0173] Among them, Q fluid represents the heat exchange between the immersion liquid and the battery cell, h represents the convection heat transfer coefficient, t fluid Indicates the immersion liquid temperature; t xil represents the temperature of the adjacent grid blocks along the length direction of the edge grid block; Δx il Indicates the lengthwise size of the adjacent grid blocks of the edge grid blocks.

[0174] For example, in the longitudinal direction, when the previous adjacent structure of the edge grid block is the immersion liquid and the next adjacent structure is the internal grid block, the second discrete equation is:

[0175]

[0176] In the width direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0177]

[0178] Q fluid =h(t fluid -t ijk )Δx i Δz k ;

[0179] t yjl represents the temperature of the adjacent grid blocks along the width direction of the edge grid block; Δy jl Indicates the size of the adjacent grid blocks along the length direction of the edge grid blocks along the width direction;

[0180] For example, in the width direction, when the previous adjacent structure of the edge grid block is the immersion liquid and the next adjacent structure is the internal grid block, the second discrete equation is:

[0181]

[0182] In the height direction, when the adjacent structure of the edge grid block includes the immersion liquid, the second discrete equation is

[0183]

[0184] Q fluid =h(t fluid -t ijk )Δx i Δy j ;

[0185] t zkl represents the temperature of the adjacent grid blocks along the height direction of the edge grid block; Δz kl Indicates the size of the adjacent grid blocks along the length direction of the edge grid block along the height direction;

[0186] For example, in the height direction, when the upper adjacent structure of the edge grid block is the immersion liquid and the lower adjacent structure is the internal grid block, the second discrete equation is:

[0187]

[0188] S350. For the edge grid block, based on the adjacent structure of the edge grid block including solid components, the three-dimensional heat conduction equation is spatially discretized to obtain a third discrete equation corresponding to the edge grid block. The third discrete equation includes the temperature of the edge grid block and its relationship with the temperature of the adjacent grid blocks in at least one direction of the length direction, the width direction and the height direction, as well as the temperature of the solid components.

[0189] Specifically, for edge grid blocks of adjacent structures including solid components, the spatial variables of the three-dimensional conduction equation are uniformly discretized to obtain a third discrete equation corresponding to the edge grid block.

[0190] In the case where the adjacent structures of the edge grid blocks in the length direction include solid components, the third discrete equation is

[0191]

[0192] Where Δx' is equal to Δx i and Δx s The average of λ' is equal to λ x and λ sx The average of Δx i represents the size of the edge grid block along the length direction, Δx s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sx represents the thermal conductivity of a solid component along its length; t xs Represents the temperature of the solid component adjacent to the edge mesh block in the length direction.

[0193] Where Δx' can be equal to Δx i and Δxs The arithmetic mean of λ can also be the harmonic mean. λ' can be equal to λ x and λ sx The arithmetic mean of can also be the harmonic mean. For example,

[0194] For example, in the longitudinal direction, when the previous adjacent structure of the edge grid block is a solid component and the next adjacent structure is an internal grid block, the third discrete equation is:

[0195]

[0196] In the width direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0197]

[0198] Where Δy' is equal to Δy j with Δy s The average of λ is equal to λ y and λ sy The average of Δy j represents the size of the edge grid block along the width direction, Δy s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sy represents the thermal conductivity of a solid component along its length; t ys Represents the temperature of solid components adjacent to the edge mesh block in the width direction.

[0199] Where Δy' can be equal to Δy j with Δy s The arithmetic mean of λ can also be the harmonic mean. λ" can be equal to λ y and λ sy The arithmetic mean of can also be the harmonic mean. For example,

[0200] For example, in the width direction, when the previous adjacent structure of the edge grid block is a solid component and the next adjacent structure is an internal grid block, the third discrete equation is:

[0201]

[0202] In the height direction, when the adjacent structure of the edge grid block includes solid components, the third discretization equation is

[0203]

[0204] Δz' equals Δz k With Δzs The average of λ' is equal to λ z and λ sz The average value, Δz k represents the size of the edge grid block along the height direction, Δz s represents the size of the solid component adjacent to the edge grid block along the length direction; λ sz represents the thermal conductivity of the solid component along the length direction, t zs Represents the temperature of solid components adjacent to the edge mesh block in the height direction.

[0205] Where Δz' can be equal to Δz k With Δz s The arithmetic mean of λ can also be the harmonic mean. λ"' can be equal to λ z and λ sz The arithmetic mean of can also be the harmonic mean. For example,

[0206] For example, in the height direction, when the upper adjacent structure of the edge grid block is a solid component and the lower adjacent structure is an internal grid block, the third discrete equation is:

[0207]

[0208] The embodiment of the present invention also provides a method for determining the temperature of a battery cell in an immersion energy storage system. Figure 7 This is a flow chart of a method for determining the temperature of a battery cell in an immersion energy storage system provided by an embodiment of the present invention. Figure 7 The method for determining the temperature of the battery cell in the immersion energy storage system includes:

[0209] S410: Obtain a cell model, where the cell model includes discrete equations corresponding to grid blocks divided into the cell.

[0210] The discrete equation is modeled using the cell modeling method for an immersion energy storage system in any embodiment of the present invention.

[0211] S420: Determine the temperature corresponding to the grid block according to the battery cell model.

[0212] In some embodiments, boundary conditions can also be obtained, where the boundary conditions include known boundary temperature, known heat flow, or known convective heat transfer. Exemplarily, the case where the boundary temperature is known is when the temperature of the edge grid block of the battery cell is known, or the temperature of the adjacent structure of the edge grid block, such as a solid component or immersion liquid, is known. In some embodiments, the boundary conditions can also include two of the known boundary temperature, known heat flow, and known convective heat transfer. Exemplarily, in the length direction of the battery cell, the temperature of the edge grid block on the first side is known, or the temperature of the adjacent structure of the edge grid block on the first side, such as a solid component or immersion liquid, is known, and the heat flow on the second side is known. The first side and the second side are two opposite sides in the length direction of the battery cell.

[0213] In this step, iterative calculations can be performed based on the cell model and boundary conditions to obtain the temperature corresponding to each grid block of the cell, and then the actual temperature distribution of the cell can be obtained, thereby improving the accuracy of the determined temperature.

[0214] Figure 8 : is a structural diagram of an electronic device provided by an embodiment of the present invention. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0215] like Figure 8 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., which is communicatively connected to the at least one processor 11. The memory stores a computer program that can be executed by the at least one processor. The processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 into the random access memory (RAM) 13. Various programs and data required for the operation of the electronic device 10 can also be stored in the RAM 13. The processor 11, ROM 12, and RAM 13 are connected to each other via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0216] Multiple components in the electronic device 10 are connected to the I / O interface 15, including an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a magnetic disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0217] The processor 11 may be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors that run machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the cell modeling method in the submerged energy storage system of any embodiment of the present invention, or the cell temperature determination method in the submerged energy storage system of the above-mentioned embodiment of the present invention.

[0218] In some embodiments, the method for modeling a cell in an immersed energy storage system according to any embodiment of the present invention, or the method for determining the temperature of a cell in an immersed energy storage system according to the above embodiment of the present invention may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the method for modeling a cell in an immersed energy storage system according to any embodiment of the present invention, or the method for determining the temperature of a cell in an immersed energy storage system according to the above embodiment of the present invention may be executed. Alternatively, in other embodiments, the processor 11 may be configured to execute the method for modeling a cell in an immersed energy storage system according to any embodiment of the present invention, or the method for determining the temperature of a cell in an immersed energy storage system according to the above embodiment of the present invention, by any other appropriate means (e.g., by means of firmware).

[0219] Various embodiments of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0220] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer program is executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer program may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0221] In the context of the present invention, computer-readable storage media can be tangible media that can contain or store a computer program for use with an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. Computer-readable storage media can include but are not limited to electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, computer-readable storage media can be machine-readable signal media. More specific examples of machine-readable storage media can include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0222] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0223] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0224] A computing system may include clients and servers. The clients and servers are typically remote from each other and typically interact via a communication network. This client-server relationship arises through computer programs running on the respective computers, creating a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host. This server is a hosting product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosting and VPS services.

[0225] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. This is not limited herein.

[0226] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for modeling a battery cell in an immersion energy storage system, characterized in that: include: Dividing the battery cell into at least two grid blocks along the length, width and height directions of the battery cell respectively; Obtaining a three-dimensional heat conduction equation of the battery cell; Based on the position of the grid block, the three-dimensional heat conduction equation of the battery cell is discretized to obtain a discrete equation corresponding to the grid block, wherein the discrete equation includes a temperature relationship between the grid block and an adjacent structure, and the adjacent structure includes other grid blocks, solid components of the battery cell and at least one of an immersion liquid.

2. The method for modeling a battery cell in an immersion energy storage system according to claim 1, wherein: The battery cell is divided into at least two grid blocks along the length direction, width direction and height direction of the battery cell respectively, comprising: Dividing the battery cell equally into at least two grid blocks along the length, width and height directions of the battery cell respectively; Alternatively, the battery cell is unequally divided into at least two grid blocks along at least one of the length direction, the width direction and the height direction of the battery cell.

3. The method for modeling a battery cell in an immersion energy storage system according to claim 1, wherein: The at least two grid blocks include an edge grid block and an inner grid block; along at least one of the length direction, the width direction, and the height direction, the adjacent structure of the edge grid block is the solid component or the immersion liquid; Along the length direction, the width direction and the height direction, the adjacent structures of the internal grid block are all other grid blocks; The three-dimensional heat conduction equation of the battery cell is discretized based on the position of the grid block to obtain a discrete equation corresponding to the grid block, including: For the internal grid block, spatially discretizing the three-dimensional heat conduction equation to obtain a first discrete equation corresponding to the internal grid block, the first discrete equation including a relationship between the temperature of the internal grid block and the temperatures of other adjacent grid blocks in the length direction, the width direction, and the height direction, respectively; For the edge grid block, based on the adjacent structure of the edge grid block including the immersion liquid, spatially discretizing the three-dimensional heat conduction equation to obtain a second discrete equation corresponding to the edge grid block, the second discrete equation including a temperature of the edge grid block, a relationship between the temperature of the grid block adjacent to the edge grid block in at least one of the length direction, the width direction, and the height direction, and the temperature of the immersion liquid; For the edge grid block, based on the adjacent structure of the edge grid block including the solid component, the three-dimensional heat conduction equation is spatially discretized to obtain a third discrete equation corresponding to the edge grid block. The third discrete equation includes the temperature of the edge grid block, the temperature relationship of the grid block adjacent to at least one direction of the length direction, the width direction and the height direction, and the solid component.

4. The method for modeling a battery cell in an immersion energy storage system according to any one of claims 1 to 3, characterized in that: The three-dimensional heat conduction equation of the battery cell is discretized based on the position of the grid block to obtain a discrete equation corresponding to the grid block, including: Based on the position of the grid block, the central difference format of the finite difference method is used to discretize the three-dimensional heat conduction equation of the battery core to obtain a discrete equation corresponding to the grid block.

5. The method for modeling a battery cell in an immersion energy storage system according to claim 3, wherein: The three-dimensional heat conduction equation is in the form of a three-dimensional transient zone heat source, and the three-dimensional heat conduction equation is: Wherein, ρ represents the density of the battery cell; c represents the specific heat capacity of the battery cell; t represents temperature, τ represents time; λ x ,λ y ,λ z The thermal conductivities in the length direction, the width direction, and the height direction, respectively; is the heating power density of the battery cell.

6. The method for modeling a battery cell in an immersion energy storage system according to claim 5, characterized in that: The battery cell is evenly divided into a plurality of grid blocks along the length, width and height directions of the battery cell; The first discrete equation is: where, t ijk represents the temperature of Wijk, and Wijk represents the i-th grid block in the length direction, the j-th grid block in the width direction, and the k-th grid block in the height direction; where, 2 ≤ i < m, m is the total number of grid blocks divided along the length direction, m ≥ 2; 2 ≤ j < n, n is the total number of grid blocks divided along the width direction, n ≥ 2; 2 ≤ k < p, p is the total number of grid blocks divided along the height direction, p ≥ 2; and i, j, k, m, n, and p are all positive integers; t xi+1 Indicates the temperature of the next grid block of Wijk in the length direction, t xi-1 Indicates the temperature of the previous grid block of Wijk in the length direction; t yj+1 Indicates the temperature of the next grid block of Wijk in the width direction, t yj-1 Indicates the temperature of the previous grid block of Wijk in the width direction; t zk+1 Indicates the temperature of the next grid block of Wijk in the height direction, t zk-1 represents the temperature of the previous grid block of Wijk in the height direction; Δx represents the size of the grid block along the length direction, Δy represents the size of the grid block along the width direction, and Δz represents the size of the grid block along the height direction; In the longitudinal direction, when the adjacent structure of the edge grid block includes immersion liquid, the second discrete equation is: Q fluid =h(t fluid -t ijk )ΔyΔz; Among them, Q fluid represents the heat exchange between the immersion liquid and the battery cell, h represents the convection heat transfer coefficient, t fluid Indicates the immersion liquid temperature; t xil Indicates the temperature of the adjacent grid blocks of the edge grid block along the length direction; In the width direction, when the adjacent structure of the edge grid block includes immersion liquid, the second discrete equation is: Q fluid =h(t fluid -t ijk )ΔxΔz;t yjl Indicates the temperature of the adjacent grid blocks of the edge grid block along the width direction; In the height direction, when the adjacent structure of the edge grid block includes immersion liquid, the second discrete equation is: Q fluid =h(t fluid -t ijk )ΔxΔy; t zkl Indicates the temperature of the adjacent grid blocks of the edge grid block along the height direction; In the longitudinal direction, when the adjacent structure of the edge grid block includes solid components, the third discrete equation is: Where Δx' is equal to Δx and Δx s The average of λ' is equal to λ x and λ sx The average of Δx s represents the size of the solid component adjacent to the edge grid block along the length direction; sx represents the thermal conductivity of the solid component along the length direction; t xs represents the temperature of the solid component adjacent to the edge grid block in the length direction; In the width direction, when the adjacent structure of the edge grid block includes solid components, the third discrete equation is: Where Δy' is equal to Δy and Δy s The average of λ is equal to λ y and λ sy The average of Δy s represents the size of the solid component adjacent to the edge grid block along the length direction; sy represents the thermal conductivity of the solid component along the length direction; t ys represents the temperature of the solid component adjacent to the edge grid block in the width direction; In the height direction, when the adjacent structure of the edge grid block includes solid components, the third discrete equation is: Δz' is equal to Δz and Δz s The average of λ' is equal to λ z and λ sy The average value, Δz s represents the size of the solid component adjacent to the edge grid block along the length direction; sz represents the thermal conductivity of the solid component along the length direction, t zs Indicates the temperature of the solid component adjacent to the edge grid block in the height direction.

7. The method for modeling a battery cell in an immersion energy storage system according to claim 5, wherein: Along at least one of the length, width and height directions of the battery core, sizes of at least two of the grid blocks are unequal; The first discrete equation is: where, t ijk represents the temperature of Wijk, and Wijk represents the i-th grid block in the length direction, the j-th grid block in the width direction, and the k-th grid block in the height direction; Δx i , Δy j , Δz k represent the dimensions of Wijk in the length direction, the width direction, and the height direction respectively; where, 2 ≤ i < m, m is the total number of grid blocks divided in the length direction, m ≥ 2; 2 ≤ j < n, n is the total number of grid blocks divided in the width direction, n ≥ 2; 2 ≤ k < p, p is the total number of grid blocks divided in the height direction, p ≥ 2; and i, j, k, m, n, p are all positive integers; t xi+1 Indicates the temperature of the next grid block of Wijk in the length direction, t xi-1 Indicates the temperature of the previous grid block of Wijk in the length direction; t yj+1 Indicates the temperature of the next grid block of Wijk in the width direction, t yj-1 Indicates the temperature of the previous grid block of Wijk in the width direction; t zk+1 Indicates the temperature of the next grid block of Wijk in the height direction, t zk-1 Indicates the temperature of the previous grid block of Wijk in the height direction; In the longitudinal direction, when the adjacent structure of the edge grid block includes immersion liquid, the second discrete equation is: Q fluid =h(t fluid -t ijk )Δy j Δz k ; Among them, Q fluid represents the heat exchange between the immersion liquid and the battery cell, h represents the convection heat transfer coefficient, t fluid Indicates the immersion liquid temperature; t xil represents the temperature of the adjacent grid blocks of the edge grid block along the length direction; Δx il represents the size of the adjacent grid blocks of the edge grid block along the length direction; In the width direction, when the adjacent structure of the edge grid block includes immersion liquid, the second discrete equation is: Q fluid =h(t fluid -t ijk )Δx i Δz k ; t yjl represents the temperature of the adjacent grid blocks of the edge grid block along the width direction; Δy jl represents the size of the adjacent grid blocks of the edge grid block along the width direction along the length direction; In the height direction, when the adjacent structure of the edge grid block includes immersion liquid, the second discrete equation is: Q fluid =h(t fluid -t ijk )Δx i Δy j ; t zkl represents the temperature of the adjacent grid blocks of the edge grid block along the height direction; Δz kl represents the size of the adjacent grid blocks of the edge grid block along the length direction along the height direction; In the longitudinal direction, when the adjacent structure of the edge grid block includes solid components, the third discrete equation is: Where Δx' is equal to Δx i and Δx s The average of λ' is equal to λ x and λ sx The average value, Δx i represents the size of the edge grid block along the length direction, Δx s represents the size of the solid component adjacent to the edge grid block along the length direction; sx represents the thermal conductivity of the solid component along the length direction; t xs represents the temperature of the solid component adjacent to the edge grid block in the length direction; In the width direction, when the adjacent structure of the edge grid block includes solid components, the third discrete equation is: Where Δy' is equal to Δy j with Δy s The average of λ is equal to λ y and λ sy The average of Δy j represents the size of the edge grid block along the width direction, Δy s represents the size of the solid component adjacent to the edge grid block along the length direction; sy represents the thermal conductivity of the solid component along the length direction; t ys represents the temperature of the solid component adjacent to the edge grid block in the width direction; In the height direction, when the adjacent structure of the edge grid block includes solid components, the third discrete equation is: Δz' equals Δz k With Δz s The average of λ' is equal to λ z and λ sz The average value, Δz k represents the size of the edge grid block along the height direction, Δz s represents the size of the solid component adjacent to the edge grid block along the length direction; sz represents the thermal conductivity of the solid component along the length direction, t zs Indicates the temperature of the solid component adjacent to the edge grid block in the height direction.

8. A method for determining the temperature of a battery cell in an immersion energy storage system, characterized in that: include: Obtaining a cell model, the cell model including discrete equations corresponding to the grid blocks into which the cell is divided, the discrete equations being modeled using the cell modeling method for an immersion energy storage system according to any one of claims 1 to 7; The temperature corresponding to the grid block is determined according to the battery cell model.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the method for modeling a battery cell in an immersion energy storage system according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the battery cell modeling method for an immersion energy storage system according to any one of claims 1 to 7 when executed.

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