Cell additive release device and method, battery system and vehicle

Abstract

The invention provides an additive release device and method for a battery cell, a battery system and a vehicle, and the additive release device for the battery cell comprises a storage structure and a release structure. The storage structure is used for storing an additive, and the release structure is used for controlling the additive in the storage structure to enter the battery cell body. According to the invention, the control of the additive entering the battery cell is realized through the release structure, so that the speed of the additive entering the battery cell is stable and controllable, the excessive increase of the impedance of the battery cell is avoided, the invalid release of the additive is reduced, and the service life of the battery cell is prolonged.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell additive release device, method, battery system, and vehicle. Background Art

[0002] Lithium battery cells contain an electrolyte, which conducts current between the positive and negative electrodes during the charge and discharge process. To improve the chemical properties of the electrolyte, some cells require the addition of additives during the charge and discharge process to make the electrolysis process more efficient. For example, a lithium battery cell has an additive release structure implemented by a composite diaphragm. One side of the composite diaphragm stores the additives, while the other side contains the electrolyte. During the charge and discharge process, the additives on one side of the composite diaphragm can slowly enter the electrolyte on the other side through the pores in the composite diaphragm.

[0003] However, the process by which additives enter the electrolyte through the composite separator is uncontrollable. If the weight of the additives entering the electrolyte is not appropriate, it can increase the impedance of the battery cell and reduce its lifespan. Therefore, controlling the process by which additives enter the electrolyte is a technical problem that needs to be solved in this field. Summary of the Invention

[0004] The present application provides a battery cell additive release device, method, battery system and vehicle to solve the problem of uncontrollable process of additives entering the battery cell in the prior art, avoid abnormal increase in battery cell impedance, and reduce the life of the battery cell.

[0005] The first aspect of the present application provides an additive release device for a battery cell, comprising: a storage structure and a release structure, wherein the storage structure is connected to the battery cell through the release structure, and the storage structure is used to store the additives of the battery cell; the release structure is used to control the additives stored in the storage structure to enter the battery cell body of the battery cell.

[0006] A second aspect of the present application provides a battery system, comprising a battery cell and the additive release device for the battery cell provided in the first aspect of the present application.

[0007] A third aspect of the present application provides a vehicle, comprising the battery system provided in the second aspect of the present application.

[0008] The fourth aspect of the present application provides a method for releasing additives from a battery cell, which is applied to the release structure in the additive release device for the battery cell provided in the first aspect of the present application. The method includes: controlling the additives stored in the storage structure to enter the battery cell body of the battery cell.

[0009] In summary, the battery cell additive release device, method, battery system and vehicle provided by the present application are provided with a storage structure for storing additives, the storage structure stores additives, and the release structure is used to control the additives in the storage structure to enter the interior of the battery cell body, thereby achieving control over the entry of the additives into the battery cell through the release structure, making the speed at which the additives enter the battery cell stable and controllable, avoiding excessive growth of the battery cell impedance, reducing the ineffective release of the additives, and increasing the service life of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0011] Figure 1 A schematic diagram of the structure of a battery used in this application;

[0012] Figure 2 This is a schematic structural diagram of a battery cell including an additive release device in the related art;

[0013] Figure 3 Schematic diagram of the release rate of additives in the related art;

[0014] Figure 4 This is a structural schematic diagram of an embodiment of an additive release device for a battery cell provided by the present application;

[0015] Figure 5 A schematic diagram of the additive release rate of the additive release device of the battery cell provided in this application;

[0016] Figure 6 A flow chart of a method for controlling an additive release device for a battery cell is provided for this application;

[0017] Figure 7 A schematic diagram of an embodiment of the mapping relationship provided in this application;

[0018] Figure 8 A schematic diagram of the additive release process for a battery cell;

[0019] Figure 9a Schematic diagram of the interior of the battery cell before the additive is released;

[0020] Figure 9b Schematic diagram of the interior of the battery cell after the additive is released and before diffusion;

[0021] Figure 9cSchematic diagram of the interior of the battery cell after the additive is diffused;

[0022] Figure 10 A schematic structural diagram of another embodiment of an additive release device for a battery cell is provided for this application;

[0023] Figure 11 This is a schematic diagram of the first structure of the additive release device for the battery cell provided in this application;

[0024] Figure 12 This is a schematic diagram of the second structure of the additive release device for the battery cell provided in this application;

[0025] Figure 13 This is a schematic diagram of the third structure of the additive release device for the battery cell provided in this application;

[0026] Figure 14 This is a schematic diagram of the fourth structure of the additive release device for the battery cell provided by this application;

[0027] Figure 15 This is a schematic diagram of the fifth structure of the additive release device for the battery cell provided by this application;

[0028] Figure 16 This is a schematic diagram of the sixth structure of the additive release device for the battery cell provided in this application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0030] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the numbers used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, 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 comprising 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.

[0031] Figure 1A schematic diagram of the structure of a battery used in this application is shown in FIG. Figure 1 The battery shown takes a lithium battery as an example. The battery cell 1 of the lithium battery includes a battery cell body 10, a positive electrode tab 101 and a negative electrode tab 102. The battery cell body 10 contains an electrolyte. Figure 1 The larger circular frame in the figure represents the distribution of electrolyte molecules 1001 in the battery cell body 10. When the positive electrode tab 1001 and the negative electrode tab 102 of the battery cell 1 are connected to an external circuit to form a loop, the electrolyte inside the battery cell body 10 can participate in the electrochemical reaction, thereby playing a role in conducting current between the positive electrode tab 1001 and the negative electrode tab 1002.

[0032] In order to improve the chemical properties of the electrolyte, some lithium battery cells 1 also add additives to the electrolyte, including film-forming additives. For example, Figure 1 The smaller black dots in the figure represent the distribution of electrolyte molecules 1002 in the battery cell body 10. The electrolyte can improve conductivity, maintain electrolyte stability, and enhance safety, making the electrolysis process of the electrolyte more efficient and reliable.

[0033] Since the additives are continuously consumed during the reaction of the electrolyte, during the entire long-term charge and discharge process of the battery cell 1, once the mass of the additives decreases, additives need to be added to the electrolyte to replenish the consumption of the additives and maintain the reaction efficiency of the electrolyte.

[0034] Figure 2 Schematic diagram of the structure of a battery cell including an additive release device in the related art, such as Figure 2 The illustrated battery cell 1 is provided with a composite separator 104. One side of the composite separator 104 contains the electrolyte, and the other side of the composite separator 104 is a storage area 103, which can store additives. The composite separator 104 has a certain sustained-release function. The concentration of additives in the storage area 103 is high, while the concentration of additives in the battery cell body 10 is low. Therefore, the additives in the storage area 103 can gradually enter the battery cell interior 10 through the composite separator 104, achieving continuous and slow addition of additives to the electrolyte.

[0035] However, in Figure 2 In the additive release device shown, the driving force for the additive to enter the battery cell body 10 from the storage area 103 is the concentration difference of the additive on both sides of the composite separator 104. For example, Figure 3 Schematic diagram of the release rate of additives in related art, such as Figure 3 Shown Figure 2In the device for releasing additives shown, the rate at which the additive enters the interior 10 of the battery cell through the composite separator 104 is shown. It can be seen that in the initial stage, due to the high concentration of the additive in the storage area 103 and the large difference in concentration of the additive on both sides of the composite separator 104, the rate at which the additive enters the interior 10 of the battery cell is relatively fast. As time passes, the concentration of the additive in the storage area 103 gradually decreases, and the difference in concentration of the additive on both sides of the composite separator 104 gradually decreases, so the rate at which the additive enters the interior 10 of the battery cell gradually slows down.

[0036] It can be seen that during the above process, the speed and mass of the additives entering the interior of the battery cell 10 are not stable. In the initial stage, the speed and mass of the additives entering the interior of the battery cell 10 are faster, while in the subsequent stages, the speed and mass of the additives entering the interior of the battery cell 10 are slower. Especially in the initial stage, when a large amount of additives enter the interior of the battery cell 10, in addition to possibly causing an excessive increase in the internal resistance (Direct Current Internal Resistance, DCIR) of the battery cell 1, it also reduces the amount of additives that can be continuously released into the interior of the battery cell 10, thereby shortening the service life of the battery cell 1.

[0037] Based on the above problems, the present application provides an additive release device for a battery cell, which continuously and stably releases additives into the battery cell body 10 during the entire operation of the battery cell 1 in a more controllable and intelligent manner, so as to avoid problems such as excessive impedance growth of the battery cell 1 and reduced service life of the battery cell 1 caused by changes in the release rate and quality of the additive. The technical solution of the present application is described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0038] Figure 4 This is a structural diagram of an embodiment of the additive release device for the battery cell provided by the present application, as shown in FIG. Figure 4 The additive release device of the battery cell shown includes a storage structure 2 and a release structure 3. The storage structure 2 is connected to the battery cell 1 through the release structure 3. The storage structure 2 is used to store the additive required for the electrolyte in the battery cell interior 10 of the battery cell 1.

[0039] The release structure 3 provided in this embodiment can be used to control the additive stored in the storage structure 2 to start entering the battery cell body 10, and to control the additive stored in the storage structure 2 to stop entering the battery cell body 10. In a specific implementation, the release structure 3 first controls the additive stored in the storage structure 2 to start entering the battery cell body 10, and then controls the additive stored in the storage structure 2 to stop entering the battery cell body 10. During the entire time range when the additive starts to enter the battery cell 10, the additive stored in the storage structure 2 can continue to enter the battery cell body 10, and after that, the additive stored in the storage structure 2 stops entering the battery cell body 10.

[0040] Therefore, the release structure 3 provided by the additive release device of the battery cell provided in this embodiment can control the entry of additives into the interior 10 of the battery cell. During the entire life cycle of the battery cell 1, the additives are not continuously released into the interior 10 of the battery cell, making the process of the additives entering the interior 10 of the battery cell controllable and thus more stable.

[0041] In one embodiment, the release structure 3 includes a controller 31 and a switch structure 32. A first end a of the switch structure 32 is connected to the storage structure 2, and a second end b of the switch structure 32 is connected to the cell body 10 of the battery cell 1. Furthermore, the second end b of the switch structure 32 is connected to the interior of the cell body 10 and is in direct contact with the electrolyte stored in the cell body 10.

[0042] The controller 31 is in communication connection with the control terminal c of the switch structure 32 . The controller 31 can control the conduction between the first terminal a and the second terminal b of the switch structure 32 through the control terminal c.

[0043] In this embodiment, the controller 31 can specifically control the conduction duration of the first end a and the second end b of the switch structure 32. For example, the controller 31 controls the first end a and the second end b of the switch structure 32 to be conductive, and after the conductive state is maintained for a first preset time, the controller 31 controls the first end a and the second end b of the switch structure 23 to be disconnected.

[0044] When the first end a and the second end b of the switch structure 32 are conductive, the additive stored in the storage structure 2 can sequentially pass through the first end a of the switch structure 32, the switch structure 32, and the second end b of the switch structure 32, ultimately entering the interior of the battery cell body 10. In some technologies, the process of allowing the additive to enter the interior of the battery cell body 10 is called an additive release process.

[0045] When the first end a and the second end b of the switch structure 32 are disconnected, the additive stored in the storage structure 2 cannot enter the interior of the battery cell body 10 through the switch structure 32 .

[0046] More specifically, Figure 5This is a schematic diagram of the additive release rate of the additive release device of the battery cell provided in this application, as shown in FIG. Figure 5 As shown, the controller 31 controls the first end a and the second end b of the switch structure 32 to be turned on at time t1, and maintains the turned-on state for the turned-on time. Then, the controller 31 controls the first end a and the second end b of the switch structure 32 to be turned off at time t2. Then, between time t1 and time t2, the additive stored in the storage structure 2 continuously enters the interior of the battery cell body 10 through the switch structure 32, and since the storage structure 2 and the battery cell body 10 are directly connected, the release rate of the additive into the interior of the battery cell body 10 also remains unchanged.

[0047] Similarly, the controller 31 controls the first end a and the second end b of the switch structure 32 to be turned on at time t3, and controls the first end a and the second end b of the switch structure 32 to be turned off at time t4. Between time t3 and time t4, the additives stored in the storage structure 2 continue to enter the battery cell body 10 through the switch structure 32, and the release speed remains unchanged.

[0048] Therefore, the additive release device for the battery cell provided in this embodiment realizes the control of the additive entering the battery cell interior 10 more intelligently through the control of the switch structure 32 by the controller 31, so that the speed of the additive entering the battery cell interior 10 is stable and controllable. Figure 2 From the comparison of the release speeds of the release devices provided in the related arts shown, it can be seen that in the initial stage, the additive release device of the battery cell provided in this embodiment has a smaller mass and a slower speed of the additive entering the interior 10 of the battery cell, thereby avoiding the excessive increase of the impedance of the battery cell 1 in the initial stage and reducing the ineffective release of more additives in the initial stage, ensuring that there will be enough additives to continue to be slowly released into the interior 10 of the battery cell in the future, thereby increasing the service life of the battery cell 1.

[0049] In one embodiment of the present application, the controller 31 may be a control unit such as a central processing unit (CPU), a microcontroller unit (MCU) or a system-on-chip (SOC). Alternatively, in another embodiment, when the additive release device for the battery cell provided in the embodiment of the present application is applied to the battery system of a vehicle and used to provide additives to the battery cell 1 of the battery system, the controller 31 may also be a battery management system (BMS) of the vehicle battery system, or the controller 31 may be a control unit integrated in the BMS. The controller 31 provided in this embodiment is simple to implement, especially when applied to the battery system of a vehicle, it can be implemented based on the vehicle's existing BMS, does not change the existing circuit structure, can save costs, and is also conducive to the promotion and application of the present application.

[0050] The following is combined with Figure 6 , the control logic of the controller 31 in the additive release device for the battery cell provided in the embodiment of the present application is introduced. Figure 6 The present application provides a flow chart of a control method for an additive release device of a battery cell, such as Figure 6 The method shown can be applied to Figure 4 In the device shown in FIG. 3 , the controller 31 executes the operation. Specifically, Figure 6 The control process of the controller 31 shown includes:

[0051] S101: The controller 31 obtains the working status information of the battery cell 1. The working status information includes one or more of the following: the number of cycles and internal resistance of the battery cell 1. The number of cycles refers to the number of cycles that the battery cell 1 completes a complete charging and discharging process.

[0052] In one embodiment, the controller 31 may receive the working status information of the battery cell 1 sent by the signal acquisition device in S101. The signal acquisition device may be a device provided on the vehicle for collecting the working status information of the battery cell 1, and the signal acquisition device may be used to send the working status information of the battery cell 1 to the controller 31. The specific implementation of the signal acquisition device is not limited in this application, and reference may be made to the device provided on the existing vehicle for collecting the number of cycles and internal resistance of the battery cell 1. The signal acquisition device may also be used to collect information such as current, voltage, and internal resistance. Alternatively, in another embodiment, the controller 31 may also receive the working status information of the battery cell 1 sent by other devices. For example, the maintenance personnel of the vehicle may send the current working status information of the battery cell 1 to the controller 31 through an electronic device.

[0053] Specifically, after obtaining the operating status information of the battery cell 1, the controller 31 may further determine the weight of the additive required for the electrolyte in the battery cell body 10 under the current operating state based on the operating status information of the battery cell 1. The weight may be measured in grams (g). Subsequently, the controller 31 determines the time for which the switch structure 32 needs to be turned on based on information such as the required weight of the additive, the flow rate of the switch structure 32, and the density of the additive.

[0054] In one embodiment, the controller 31 can store different working state information and the weight of the additive required in the current working state in advance through a mapping relationship. For example, Figure 7 This is a schematic diagram of an embodiment of the mapping relationship provided in this application, such as Figure 7 The mapping relationship shown includes a correspondence between multiple working states and the weight of the additive corresponding to the working state, for example, the correspondence between working state 1 and weight 1, the correspondence between working state 2 and weight 2, and the correspondence between working state N and weight N. After the controller 31 determines the current working state information, it determines in the mapping relationship that the current working state information is the same as working state information 2. Based on the correspondence between working state information 2 and weight 2, the controller 31 can determine that the weight of the additive currently required to be added to the cell body 10 of the battery cell 1 is weight 2. Subsequently, the controller 31 can determine the first preset duration of the conduction of the switch structure 32 based on the weight of the additive (in g), the density of the additive (in g / cm3), and the flow rate of the switch structure 32 (in cm3 / min).

[0055] In one embodiment, Figure 7 In the example shown, the working state can be a value or a range of values. For example, working state 1 includes 100 cycles of battery cell 1, working state 2 includes 200 cycles of battery cell 1... and so on. Working state 1 includes an internal resistance of battery cell 1 of 1.5mΩ, working state 2 includes an internal resistance of battery cell 1 of 1.2mΩ... and so on. For another example, working state 1 includes 0-100 cycles of battery cell 1, working state 2 includes 100-200 cycles of battery cell 1... and so on. Working state 1 includes an internal resistance of battery cell 1 of 1.45-1.55mΩ, working state 2 includes an internal resistance of battery cell 1 of 1.15-1.25mΩ... and so on.

[0056] In one embodiment, the mapping relationship can also directly store the correspondence between the working status and the conduction time, so that the controller 31 can directly determine the conduction time of the switch structure 32 based on the obtained working status information, without having to calculate the conduction time based on the weight, thereby reducing the amount of calculation required by the controller 31 and saving the computing power of the controller 31.

[0057] In one embodiment, if Figure 7 The mapping relationship shown may be preset, or specified by a relevant operator, or may be calculated by the controller 31. The mapping relationship may be stored in a storage space of the controller 31, and the controller 31 obtains the mapping relationship from the storage space when needed.

[0058] like Figure 7 The mapping relationship shown is in tabular form as an example. In other possible implementations, the mapping relationship can also be in the form of a curve or other form. For example, in one embodiment, the mapping relationship can also be obtained by collecting the weight of additives required for multiple battery cells 1 under different operating conditions, using all battery cells 1 as historical data, and establishing a regression model based on machine learning to obtain the mapping relationship. The controller 31 can determine the current weight of additives that need to be added based on the obtained mapping relationship at the time when the additive needs to be released into the battery cell interior 10 within the operating range of the battery cell 1 throughout its life cycle.

[0059] S102: The controller 31 controls the switch structure 32 to be turned on for a first preset time period according to the working status information obtained in S101, so that the additive stored in the storage structure 2 enters the battery cell body 10 through the switch structure 32 within the first preset time period, wherein the weight of the additive entering the battery cell body 10 can be determined in S101.

[0060] In one embodiment, the controller 31 can obtain the working status information of the battery cell 1 in real time, and when it determines that the current working status is about to enter the working status in the mapping relationship, it issues a notification message to inform the user or maintenance personnel of the vehicle where the battery cell 1 is located that the additive needs to be released into the battery cell interior 10 so that the vehicle can be repaired or maintained. Subsequently, during the vehicle repair or maintenance process, the controller 31 executes the above control process to release the additive into the battery cell interior 10. In this case, the controller 31 can predict the release of the additive in advance, make the decision to release the additive on behalf of the user or maintenance personnel, and issue a reminder to release the additive, which has a higher degree of intelligence.

[0061] In another embodiment, the controller 31 can obtain the working state information of the battery cell 1 in real time, and when it determines that the current working state is about to enter the working state in the mapping relationship, it actively executes the above control process to release the additive into the battery cell interior 10. In this case, the controller 31 can predict the release of the additive in advance and actively release the additive, thereby reducing the perception of users and maintenance personnel and achieving a higher degree of automation.

[0062] In another embodiment, during repair or maintenance of the vehicle, when the controller 31 receives an instruction to release the additive from the BMS or other equipment, the controller 31 executes the above control process to release the additive into the interior 10 of the battery cell.

[0063] In summary, the additive release device for the battery cell provided in this embodiment controls the switch structure 31 by the controller 31 according to the working status information of the battery cell 1, thereby controlling the additive to enter the battery cell body 10 at the required time and in a more appropriate amount, which not only improves the intelligence level of the controller 31, but also ensures the stable and effective release of the additive throughout the life cycle of the battery cell 1.

[0064] When the additive release device for the battery cell provided in this embodiment is used in a vehicle, it can improve the intelligence and automation level of the vehicle battery system, and increase the service life of the vehicle battery system, thereby improving the user experience and driving experience of the vehicle user.

[0065] In the above embodiment, the structure and control method of the additive release device for the battery cell are described. Through the above device and its control method, the additive can be introduced from the storage structure 2 into the battery cell body 10 through the switch structure 32. In actual application, after the additive is released into the battery cell body 10, the next step is to diffuse the additive within the battery cell body 10 to ensure a more uniform distribution of the additive in the electrolyte.

[0066] For example, Figure 8 The figure is a schematic diagram of the additive release process of a battery cell. The first step is to release the additive in the storage structure 2 into the battery cell body 10 through the switch structure 32, and the second step is to diffuse the additive inside the battery cell body 10. Figures 4 to 7 The embodiment shown completes the Figure 8 The first step of additive release is shown.

[0067] For example, Figure 9a This is a schematic diagram of the interior of the battery cell before releasing the additive. There are relatively few additive molecules 1002 in the battery cell body 10 . Subsequently, the controller 31 can control the switch structure 32 to be turned on for a preset time to allow the additive to enter the battery cell body 10 .

[0068] Figure 9b This is a schematic diagram of the interior of the battery cell after the additive is released and before diffusion. When the additive enters the battery cell body 10, the second end of the switch structure 32 is connected to the area 100 of the battery cell body 10 where the number of additive molecules 1002 is large, while the number of additive molecules 1002 in other areas of the battery cell body 10 is small. The controller 31 can then execute Figure 8 The second step of the diffusion of additives is shown.

[0069] In one embodiment of the present application, refer to Figure 9b In the state shown, since the concentration of the additive in the region 100 is higher and the concentration of the additive in other regions is lower, the concentration difference can cause the additive molecules 1002 in the region 100 to gradually diffuse to other regions.

[0070] Figure 9c Schematic diagram of the interior of the cell after the additive has diffused. When the concentration of the additive in region 100 is the same as that in other regions, the second step of the additive diffusion is completed. At this time, the number of additive molecules 1002 in the cell body 10 is equal to that in the other regions. Figure 9a The amount is greater and more evenly distributed than before the additive is released.

[0071] Figure 10 The present application provides a schematic structural diagram of another embodiment of the additive release device for the battery cell, as shown in FIG. Figure 10 The device shown in Figure 4 In addition to the structure shown, a heating structure 33 is also included. The heating structure 33 can be a cooling circulation system of the vehicle, etc., and the heating structure 33 is arranged outside the battery cell body 10. Alternatively, the heating structure 33 can also be a self-heating circuit of the battery cell 1, etc. The embodiment of the application does not limit the specific implementation of the heating structure 33. It can be already installed on the vehicle or it can be specially installed.

[0072] The controller 31 is connected to the heating structure 33 and can control the heating structure 33 to heat the battery cell body 10. For example, after the controller 31 controls the first and second terminals of the switch structure 32 to be conductive for a first preset time, the controller 31 controls the heating structure 33 to begin heating the battery cell body 10 at a preset temperature for a second preset time. For example, the preset heating temperature can be set to 40°C to 60°C, and the second preset time can be set to 24-78 hours.

[0073] During the second preset time period of heating by the heating structure 33, the additive molecules 1002 in the region 100 gradually diffuse to other regions. Since the temperature inside the cell body 10 is higher under the heating of the heating structure 33, the diffusion speed of the additive molecules 1002 is faster. The distribution of the additive inside the cell body 10 can be seen from the Figure 9b The state shown in spreads more quickly as Figure 9c The status shown.

[0074] In summary, this embodiment provides an additive release device for a battery cell. After releasing the additive into the interior of the battery cell body 10, the controller 31 also controls the heating structure 33 to heat the battery cell body 10, thereby increasing the diffusion rate of the additive, making the entire process of adding the additive to the interior of the battery cell 10 less time-consuming and more efficient.

[0075] The specific structure of the additive release device for the battery cell provided in this application is introduced below with reference to the accompanying drawings.

[0076] Figure 11 This is a schematic diagram of the first structure of the additive release device for the battery cell provided in this application, as shown Figure 11 The storage structure 2 of the additive release device of the illustrated battery cell can be shaped like a regular rectangular parallelepiped, the dimensions of which can be determined by the available space within the battery cell 1. Furthermore, the dimensions of the storage structure 2 in the direction of gravity G are greater than the thickness of the material used for the storage structure 2 in the direction of gravity G. The material of the storage structure 2 can be PP / PE or other materials that are stable with the electrolyte and additives. The space within the storage structure 2 is used to store the additives. The storage structure provided in this embodiment has an excellent function of preserving the electrolyte additives and is not prone to leakage throughout the storage cycle.

[0077] like Figure 11 The switch structure 32 shown is a solenoid valve, which can be a normally closed micro solenoid valve. In one possible implementation, it includes a solenoid coil, a valve core, a sealing ring, a spring, a valve seat, a liquid inlet and a liquid outlet. Figure 11 In the figure, the first end a of the switch structure 32 is the liquid inlet, which is connected to the first opening 201 on the surface of the storage structure 2, and the second end b of the switch structure 32 is the liquid outlet, which is connected to the second opening on the surface of the battery cell 10.

[0078] exist Figure 11 In the embodiment shown, the first opening 201 is designed on the lower surface of the storage structure 2 in the gravity direction G. When the switch structure 32 is turned on, the additive inside the storage structure 2 enters the battery cell body 10 through the switch structure 32 under the action of gravity.

[0079] The control principle of the solenoid valve is as follows: when the solenoid valve receives a control signal sent by the controller 31 and is energized, the electromagnetic coil generates an electromagnetic force to lift the valve core from the valve seat, the valve opens, and the liquid inlet and the liquid outlet are connected; when the solenoid valve is de-energized, the electromagnetic force disappears, the spring presses the valve core onto the valve seat, the valve closes, and the liquid inlet and the liquid outlet are disconnected.

[0080] like Figure 11The illustrated device also includes a communication structure 34, specifically at least one connecting line. The controller 31 is connected to the control terminal c of the switch structure 32 via the at least one connecting line. The controller 31 can send a first control signal to the control terminal c of the switch structure 32 via the at least one connecting line, thereby connecting the first terminal a and the second terminal b of the switch structure 32 in accordance with the first control signal. Furthermore, the controller 31 can also send a second control signal to the control terminal c of the switch structure 32 via the at least one connecting line, thereby disconnecting the first terminal a and the second terminal b of the switch structure 32 in accordance with the second control signal.

[0081] The specific forms of the first control signal and the second control signal can be voltage or current, etc. Figure 11 In the device shown, when the switch structure 32 is a solenoid valve, the first control signal is a high level sent by the controller 31 to the solenoid valve, and the second control signal is a low level sent by the controller 31 to the solenoid valve, or the second control signal can be a 0 voltage signal when no level signal is sent.

[0082] The additive release device for the battery cell provided in this embodiment is designed with a regular rectangular storage structure 2 and adopts an existing relatively mature electromagnetic valve to realize the switch structure 32, and has the characteristics of simple structure, easy implementation and low cost.

[0083] Figure 12 This is a schematic diagram of the second structure of the additive release device for the battery cell provided in this application, as shown Figure 12 The storage structure 2, the switch structure 32 and the battery cell 10 of the additive release device of the battery cell are shown. Figure 11 The structure shown is the same except that Figure 12 The communication structure 34 in is a wireless communication module. The wireless communication module can be built into the switch structure 32 and connected to the control end c of the switch structure 32. The controller 31 can send a first control signal through the network, and the wireless communication module can receive the first control signal through the network, and control the first end a and the second end b of the switch structure 32 to be turned on according to the first control signal according to the first control signal. In addition, the controller 31 can send a second control signal through the network, and the wireless communication module can receive the second control signal through the network, and control the first end a and the second end b of the switch structure 32 to be turned off according to the first control signal according to the second control signal. In the additive release device for the battery cell provided in this embodiment, the controller 31 can send a control signal to the switch structure 32 through wireless communication, thereby further simplifying the structural complexity and reducing the occupation and impact on the internal space of the battery cell 1.

[0084] Figure 13 This is a schematic diagram of the third structure of the additive release device for the battery cell provided in this application, as shown Figure 13Another arrangement of the first opening on the storage structure 2 is shown, wherein the first opening 201 is designed on the side surface of the storage structure 2 in the direction of gravity G. The horizontal midline of the side surface divides the side surface into two parts, an upper part and an lower part, and the first opening 201 is located in the lower part of the side surface. When the switch structure 32 is turned on, the additive inside the storage structure 2 can also enter the interior of the battery cell body 10 through the switch structure 32 under the action of gravity. This embodiment provides more arrangements for the first opening of the storage structure 2, improves the flexibility of the arrangement, and enables the additive release device of the battery cell to be applied to different structures.

[0085] Figure 14 This is a schematic diagram of the fourth structure of the additive release device for the battery cell provided in this application, as shown Figure 14 Another arrangement of the storage structure 2 is shown, wherein the storage structure 2 can extend above the switch structure 32, thereby making full use of the space around the switch structure 2 and improving the utilization rate of the internal space of the battery cell 1.

[0086] Figure 15 This is a schematic diagram of the fifth structure of the additive release device for the battery cell provided in this application, as shown Figure 15 FIG1 shows a schematic diagram of a second opening 100 on the battery cell body 10, wherein the second opening 100 is arranged on the upper surface of the battery cell body 10 in the gravity direction G and is arranged next to a tab of the battery cell 1. Figure 15 In the example shown, taking the second opening 100 being provided next to the negative electrode tab 102 as an example, the second end b of the switch structure 32 enters the interior of the battery cell body 10 through the second opening 100 and directly contacts the electrolyte inside the battery cell body 10 .

[0087] Figure 16 This is a schematic diagram of the sixth structure of the additive release device for the battery cell provided in this application, as shown in FIG. Figure 16 The additive release device for the battery cell provided in this embodiment shows that the battery cell body 10, the storage structure 2, and the switch structure 32 are all encapsulated in the same housing 11 of the battery cell 1. From the outside of the housing 11, the housing 11 can be seen as a whole, and only the positive electrode tab 101 and the negative electrode tab 102 of the battery cell 1 extend outside the housing 11.

[0088] In one embodiment, the controller 32 may be disposed outside the housing 11. When the controller 32 is connected to the switch structure 32 via a connecting wire, at least one connecting wire extends from the interior of the housing 11 to the exterior of the housing 11. The connecting wire may be formed by connecting a lead sheet material, a fuse block material, etc. in series, wherein the fuse block material is disposed in the direction of gravity G.

[0089] The additive release device for the battery cell provided in this embodiment can encapsulate the newly added storage structure 2 and the switch structure 32 in an existing shell 11 of the battery cell body 10. It can be flexibly arranged according to the available space in the shell 11, thereby avoiding the influence of the newly added structure on the external structure of the battery cell 1. It can be applied to the structure of the existing battery cell 1, which is more conducive to the application of the embodiment of the present application in various scenarios such as battery systems and vehicles.

[0090] This application also provides an experimental method and steps for comparing the additive release device for the battery cell provided herein with additive release devices for battery cells in the related art. The experiment is divided into two parts: the first part verifies the additive release device for the battery cell provided herein, and the second part verifies the additive release device for battery cells in the related art. The two parts of the experiment are described below.

[0091] Experiment Part 1:

[0092] Step 1: Prepare the positive electrode sheet. The main materials of the positive electrode sheet include nickel-cobalt-manganese ternary materials, lithium iron phosphate materials, lithium cobalt oxide materials, lithium manganese oxide materials, and composite materials of these materials. Conductive agents include conductive carbon black, carbon nanotubes, graphene, and composite materials of these materials. Binders include PVDF, PVP, and composite materials of these materials. Dispersants include CMC, etc. Solvents include NMP, water, and composite materials of these materials.

[0093] Preferably, the main material of the positive electrode active material is nickel, cobalt and manganese, conductive carbon black is used as a conductive agent, PVDF is used as a binder, and NMP is used as a solvent.

[0094] Preferably, the process for making the positive electrode sheet is an oil-based coating process, which includes the following steps: mixing the main material, conductive agent, binder, and solvent in a certain proportion to obtain positive electrode slurry, and coating it on the aluminum current collector.

[0095] Step 2: Make the negative electrode sheet. The main materials of the negative electrode sheet include: graphite materials, silicon materials, silicon-carbon materials, lithium metal materials, etc., and composite materials of these materials. Conductive agents include conductive carbon black, carbon nanotubes, graphene and other materials, as well as composite materials of these materials. Binders include PVDF, PVP, SBR and other materials, as well as composite materials of these materials. Dispersants include CMC and other materials, as well as composite materials of these materials. Solvents include NMP, water and other materials, as well as composite materials of these materials.

[0096] Preferably, the main material of the negative electrode active material is graphite, conductive carbon black is used as a conductive agent, SBR is used as a binder, CMC is used as a dispersant, and water is used as a solvent.

[0097] Preferably, the process for making the negative electrode sheet is a water-based coating process, which includes the following steps: mixing the main material, conductive agent, binder, dispersant, and solvent in a certain proportion to obtain the negative electrode dressing area slurry, and coating it on the copper current collector.

[0098] The battery cell contains a liquid electrolyte, which includes a lithium salt, a solvent, and an additive. The lithium salts include LiPF6, LiDFOB, LiFSI, LiTFSI, and their complexes; the solvents include ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, fluoroethylene carbonate, and their complexes; and the additives include VC, TMSP, LiFSI, LiTFSI, LiPO2F2, and their complexes. Preferably, the lithium salt is LiPF6, with a concentration of 0.5 to 1.5 mol / L. The solvent is selected from a ratio of EC:EMC between 10:90 (mass ratio) and 40:60 (mass ratio), preferably 30:70 (mass ratio). Preferably, the additive is VC, with an initial addition amount of 1% to 10% (mass ratio). Preferably, the initial addition amount is 4%.

[0099] Step 3: Assemble the battery cell. The battery cell capacity calculated based on the positive electrode as the capacity limit is preferably 20AH, the battery cell thickness is 10-20mm, the battery cell length is 300-500mm, the battery cell width is 200-400mm, and the lead-out tab is located in the longitudinal direction.

[0100] Step 4: Install the additive release device for the battery cell. The additive release device for the battery cell provided in the previous embodiment of the present application is placed in the lead-out space of the soft-pack battery cell. Its thickness is limited to 10 to 20 mm, its length is limited to 300 to 500 mm, and its width is the remaining space, which is 10 to 30 mm in size. The amount of liquid stored is 30 to 300 cm 3 The space occupancy coefficient of the micro-solenoid valve is set to 0.1-0.5, resulting in an effective liquid storage capacity of 3-150g for the additive release device. Preferably, the liquid storage capacity is set to 15g, and the electrolyte composition in the liquid storage tank is 50-90% VC + 50 + 10% EA (by weight). Preferably, the electrolyte composition in the liquid storage tank in this experiment is 6g VC + 9g EA.

[0101] Step 5: Inject electrolyte: Inject 0.5-1.5 mol / L EC:EMC (30:70) + 1-10% VC into the battery cell, with an injection volume of 100-200 g; preferably, the injection volume is 120 g.

[0102] Step 6: Pre-package the battery cells and leave air pockets.

[0103] Step 7: Form the cells at a current of 0.1C to 1C and perform capacity screening.

[0104] Step 8: Release verification of soft-pack single cell. Remove excess aluminum-plastic film from the battery and seal the cell.

[0105] Step 9: Battery cycle at 60°C: Place the above battery cells in a 60°C constant temperature oven and perform constant current and constant voltage charge and discharge tests.

[0106] Step 10: Additive release. According to the additive consumption model, it is predicted that about 1wt% of VC content will be consumed every 100 cycles. After 100 cycles at 60°C, the BMS controls the micro-solenoid valve to open the flow valve through the controller. It is known that the electrolyte (without additives) injection volume is 120g, the additive dosage is 4g, and the additive consumption during the first formation is about 3wt%. Therefore, the first stage of the additive needs to release 1g of additive, that is, 1.5g of electrolyte needs to be released. The electrolyte density is 1.1g / cm 3 , then the electrolyte volume is 1.4cm3; the flow rate of the flow valve is known to be 1cm3 / min, so the flow valve needs to be opened for 1.4min; considering the tolerance coefficient of 0.5~1.5, the release time is set to 2min.

[0107] Step 11: Heat diffusion and re-formation: Place the single battery in an oven at 40-60°C for 24-78 hours. After cooling for 6 hours, form the battery cell at a current of 0.1C-1C.

[0108] Repeat steps 9, 10, and 11 above, testing the battery capacity and DCIR at cycles 0, 100, 200, 300, 400, 500, and 600, respectively. Also, test the additive content at cycles 1, 101, 201, 301, 401, 501, and 600. Label the experimental group cells used in the first part of the experiment A1, A2, A3, A4, A5, and A6.

[0109] Experiment Part 2:

[0110] Step 1: Prepare the positive electrode sheet. The main materials for the positive electrode sheet include nickel-cobalt-manganese ternary materials, lithium iron phosphate materials, lithium cobalt oxide materials, lithium manganese oxide materials, and composites of these materials. Conductive agents include conductive carbon black, carbon nanotubes, graphene, and composites of these materials. Binders include PVDF, PVP, and composites of these materials. Dispersants include CMC, and solvents include NMP, water, and composites of these materials.

[0111] Preferably, the positive electrode active main material is nickel, cobalt and manganese, conductive carbon black is used as a conductive agent, PVDF is used as a binder, and NMP is used as a solvent.

[0112] Preferably, the process for making the positive electrode sheet is an oil-based coating process, and its preparation process is: after the main material, conductive agent, binder, and solvent are evenly mixed in a certain proportion, the positive electrode slurry can be obtained, and then coated on the aluminum current collector.

[0113] Step 2: Prepare the negative electrode sheet. The main materials for the negative electrode sheet include graphite, silicon, silicon-carbon, lithium metal, and composites thereof; conductive agents include conductive carbon black, carbon nanotubes, graphene, and composites thereof; binders include PVDF, PVP, SBR, and composites thereof; dispersants include CMC and composites thereof; and solvents include NMP, water, and composites thereof.

[0114] Preferably, the negative electrode active main material is graphite, conductive carbon black is used as a conductive agent, SBR is used as a binder, CMC is used as a dispersant, and water is used as a solvent.

[0115] Preferably, the process for making the negative electrode sheet is a water-based coating process, and its preparation process is: after the main material, conductive agent, binder, dispersant, and solvent are evenly mixed in a certain proportion, the negative electrode dressing area slurry can be obtained and coated on the copper current collector.

[0116] The battery cell contains a liquid electrolyte, which includes a lithium salt, a solvent, and an additive. The lithium salts include LiPF6, LiDFOB, LiFSI, LiTFSI, and their complexes; the solvents include ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, fluoroethylene carbonate, and their complexes; and the additives include VC, TMSP, LiFSI, LiTFSI, LiPO2F2, and their complexes. Preferably, the lithium salt is LiPF6, with a concentration of 0.5 to 1.5 mol / L. The solvent is selected from a ratio of EC:EMC between 10:90 (mass ratio) and 40:60 (mass ratio), preferably 30:70 (mass ratio). Preferably, the additive is VC, with an initial addition amount of 1% to 10% (mass ratio), preferably 4%.

[0117] Step 3: Assemble the battery cell. The battery cell capacity calculated based on the positive electrode as the capacity limit is preferably 20AH, the battery cell thickness is 10-20mm, the battery cell length is 300-500mm, the battery cell width is 200-400mm, and the lead-out tab is located in the longitudinal direction.

[0118] Step 4: Inject electrolyte: Inject 0.5-1.5 mol / L EC:EMC (30:70) + 1-10% VC into the battery cell, with an injection volume of 100-200 g; preferably, the injection volume is 120 g + 24 g VC.

[0119] Step 5: Pre-package the battery cells and leave air pockets.

[0120] Step 6: Form the cells at a current of 0.1C to 1C and perform capacity screening.

[0121] Step 7: Battery 60℃ cycle: Place the above battery cells in a 60℃ constant temperature oven and perform constant current and constant voltage charge and discharge tests.

[0122] Step 8: Additive release. Figure 2-Figure 3 The release speed of the additive release device shown gradually releases the additive into the battery cell during the entire working process of the battery cell, wherein the mass of the additive released in the initial stage is greater and the mass of the additive released subsequently gradually decreases.

[0123] The battery capacity and DCIR were tested at cycles 0, 100, 200, 300, 400, 500, and 600. The additive content was also tested at cycles 1, 101, 201, 301, 401, 501, and 600. The control group cells used in the second part of the experiment were labeled B1, B2, B3, B4, B5, and B6.

[0124] After the above two parts of experiments, the collected data can be represented by the following Tables 1 to 3.

[0125] Table 1

[0126] battery cells 1 lap 101 laps 201 laps 301 laps 401 laps 501 laps 600 laps A1 1.5％ 1.1％ 1.2％ 1.2％ 1.3％ 1.5％ 1.0％ A2 1.4％ 1.1％ 1.2％ 1.2％ 1.3％ 1.5％ 1.0％ A3 1.4％ 1.1％ 1.2％ 1.2％ 1.3％ 1.5％ 1.0％ A4 1.5％ 1.1％ 1.2％ 1.2％ 1.3％ 1.5％ 1.0％ A5 1.4％ 1.1％ 1.2％ 1.2％ 1.3％ 1.5％ 1.0％ A6 1.5％ 1.1％ 1.2％ 1.2％ 1.3％ 1.5％ 1.0％ B1 6.9％ 5.4％ 4.4％ 3.0％ 2.3％ 1.6％ 0.9％ B2 6.9％ 5.4％ 4.2％ 3.0％ 2.3％ 1.6％ 0.9％ B3 6.9％ 5.4％ 4.2％ 3.0％ 2.3％ 1.6％ 0.9％ B4 6.9％ 5.4％ 4.2％ 3.0％ 2.3％ 1.6％ 0.9％ B5 6.9％ 5.4％ 4.2％ 3.0％ 2.3％ 1.6％ 0.9％ B6 6.9％ 5.4％ 4.2％ 3.0％ 2.3％ 1.6％ 0.9％

[0127] Table 2

[0128]

[0129]

[0130] Table 3

[0131] battery cells 0 laps 100 laps 200 laps 300 laps 400 laps 500 laps 600 laps A1 20.01 19.2 18.8 18.4 18.2 17.8 17.2 A2 20.01 19.2 18.8 18.4 18.2 17.8 17.2 A3 20.02 19.2 18.8 18.4 18.2 17.8 17.2 A4 20.01 19.2 18.8 18.4 18.2 17.8 17.2 A5 20.02 19.2 18.8 18.4 18.2 17.8 17.2 A6 20.01 19.2 18.8 18.4 18.2 17.8 17.2 B1 20.00 19.2 18.6 18.2 17.8 17.2 16.8 B2 19.95 19.2 18.6 18.2 17.8 17.2 16.8 B3 19.91 19.1 18.5 18.1 17.7 17.1 16.7 B4 19.99 19.2 18.6 18.2 17.8 17.2 16.8 B5 19.96 19.2 18.6 18.2 17.8 17.2 16.8 B6 19.90 19.1 18.5 18.1 17.7 17.1 16.7

[0132] First, as can be seen in Table 1, the additive content of the battery cells in experimental groups A1-A6 remained constant at 1.0-1.5% regardless of the number of cycles (1, 100, ..., 600). In contrast, the additive content of the battery cells in control groups B1-B6 was higher at the initial stage, reaching 6.9%, but dropped to 0.9% after 600 cycles. This demonstrates that the additive release device of the battery cells provided by this application releases the additive more evenly and stably.

[0133] Secondly, Table 2 shows that the impedance of the cells in experimental groups A1-A6 remained low, ranging from 1.2-1.5 mΩ, regardless of cycle number (1, 100, ..., 600). Due to the high initial additive content, the impedance of the cells in control groups B1-B6 remained high, ranging from 1.8-3.0 mΩ.

[0134] Again, Table 3 shows that the capacity of the cells in the experimental groups A1-A6 decreased from an initial capacity of approximately 20AH to approximately 17.2 at 600 cycles. This capacity decrease was slower, resulting in a higher capacity retention rate, and therefore, the cells in the experimental groups had a longer lifespan. In contrast, the capacity of the cells in the control group B1-B6 decreased from an initial capacity of approximately 20AH to approximately 16.8 at 600 cycles. This capacity decrease was faster, resulting in a lower capacity retention rate, and therefore, the cells in the control group had a shorter lifespan.

[0135] Therefore, through the above experiments, combined with the experimental data in Tables 1 to 3, it can be determined that the additive release device for the battery cell provided in this embodiment can achieve the technical effect of avoiding excessive growth of the impedance of the battery cell and increasing the service life of the battery cell.

[0136] An embodiment of the present application further provides a battery system, comprising an additive release device for a battery cell as in any of the aforementioned embodiments of the present application.

[0137] An embodiment of the present application also provides a vehicle, which may be an electric vehicle. The vehicle includes a battery system, the battery system includes battery cells and an additive release device for the battery cells as in any of the foregoing embodiments of the present application, and the additive release device for the battery cells can be used to release additives into the interior of the battery cells.

[0138] Furthermore, the controller 31 provided in the embodiments of the present application may include a hardware structure and / or a software module, and implement the aforementioned functions in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module. Whether a particular one of the aforementioned functions is implemented in the form of a hardware structure, a software module, or a combination of a hardware structure and a software module depends on the specific application and design constraints of the technical solution.

[0139] For example, the controller 31 may be one or more integrated circuits configured to implement the above methods or steps, such as one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs). For another example, when the controller 31 is implemented by scheduling program code on a processing element, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, the controller 31 may also be implemented in the form of a system-on-a-chip (SOC).

[0140] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When software is used for implementation, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state disk (SSD)).

[0141] For example, an embodiment of the present application further provides an electronic device comprising a processor and a memory; wherein the memory is used to store computer-executable instructions, and the processor can execute the computer-executable instructions stored in the memory. When the computer-executable instructions are executed by the processor, the processor implements any of the methods or steps in the methods performed by the controller 31 in the aforementioned embodiments of the present application.

[0142] The present application also provides a computer-readable storage medium, which stores computer-executable instructions. When the computer-executable instructions are executed, they can be used to implement any method or any step in the method executed by the controller 31 in any of the aforementioned embodiments of the present application.

[0143] An embodiment of the present application further provides a chip for executing instructions, wherein the chip is used to execute any of the methods executed by the controller 31 as described above in the present application or any step in the method.

[0144] An embodiment of the present application further provides a computer program product, including a computer program, which, when executed, implements any of the methods performed by the controller 31 as described above in the present application or any step in the method.

[0145] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0146] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell additive release device, characterized in that: include: A storage structure (2) and a release structure (3), wherein the storage structure (2) is connected to the battery cell (1) via the release structure (3), and the storage structure (2) is used to store additives in the battery cell (1); The release structure (3) is used to control the additive stored in the storage structure (2) to enter the interior of the battery cell body (10) of the battery cell (1).

2. The additive release device for a battery cell according to claim 1, characterized in that: The release structure (3) comprises: a controller (31) and a switch structure (32), wherein a first end of the switch structure (32) is used to connect to the storage structure (2), and a second end of the switch structure (32) is used to connect to the battery cell body (10), and the controller (31) is in communication connection with the switch structure (32); The controller (31) is used to control the switch structure (32) to be turned on, so that the additive stored in the storage structure (2) enters the interior of the battery cell body (10) through the switch structure (32).

3. The additive release device for a battery cell according to claim 2, characterized in that: The controller (31) is used to obtain working status information of the battery cell (1), and control the switch structure (32) to be turned on for a first preset time period according to the working status information, so that the additive stored in the storage structure (2) enters the battery cell body (10) through the switch structure (32) within the first preset time period.

4. The additive release device for a battery cell according to claim 3, characterized in that: The controller (31) is also used for: Determining the weight of the additive to be released according to the working state information and a mapping relationship, wherein the mapping relationship includes a plurality of working state information and the weight of the additive corresponding to each of the working state information; The first preset time length is determined according to the weight of the additive, the density of the additive and the flow rate of the switch structure (32).

5. The additive release device for a battery cell according to claim 3 or 4, characterized in that: The working status information includes at least one of the following: the number of cycles, internal resistance and internal resistance of the battery cell (1).

6. The additive release device for a battery cell according to any one of claims 3 to 5, characterized in that: The release structure (3) further comprises a heating structure (33), wherein the heating structure (33) is communicatively connected to the controller (31), and the controller (31) is used to control the heating structure (33) to heat the battery cell body (10) at a preset temperature and for a second preset time after the first preset time.

7. The additive release device for a battery cell according to any one of claims 3 to 6, characterized in that: The release structure (3) further comprises a communication structure (34), the controller (31) is connected to the control end of the switch structure (32) via the communication structure (34), and the communication structure (34) is a connecting line or a wireless communication module; The controller (31) is also used to send a first control signal to the control end of the switch structure (32) through the communication structure (34) to control the switch structure (32) to be turned on, and to send a second control signal to the control end of the switch structure (32) through the communication structure (34) to control the switch structure (32) to be turned off.

8. The additive release device for a battery cell according to any one of claims 3 to 7, characterized in that: The first end of the switch structure (32) is connected to a first opening on the surface of the storage structure (2), and the first opening is arranged on the lower surface of the storage structure (2) in the gravity direction, or on the side surface of the storage structure (2) in the gravity direction and at a portion downward from the horizontal midline of the side surface; The second end of the switch structure (32) is connected to a second opening on the surface of the battery cell body (10), and the second opening is arranged on the upper surface of the battery cell body (10) in the gravity direction and is arranged next to a pole ear of the battery cell body (10).

9. The additive release device for a battery cell according to any one of claims 3 to 8, characterized in that: The battery cell body (10), the storage structure (2) and the switch structure (32) are encapsulated in a housing (11) of the battery cell (1).

10. A battery system, characterized in that: include: A battery cell (1) and an additive release device for the battery cell as claimed in any one of claims 1 to 9.

11. A vehicle, characterized in that: Comprising the battery system as claimed in claim 10.

12. The vehicle according to claim 11, characterized in that The controller (31) is a battery management system BMS of the vehicle; or, the controller (31) is integrated in the BMS.

13. A method for releasing additives from a battery cell, characterized in that: Applied to a release structure (3), a storage structure (2) is connected to a battery cell (1) via the release structure (3), the storage structure (2) is used to store an additive of the battery cell (1), and the method for releasing the additive of the battery cell comprises: The additive stored in the storage structure (2) is controlled to enter the interior of the battery cell body (10) of the battery cell (1).

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