Battery cell baking method and equipment

Abstract

The invention relates to a battery cell baking method and equipment. The battery cell baking method comprises the following steps: putting a test battery cell into a baking chamber; carrying out preheating treatment operation by taking the vacuum value of the baking chamber as a first vacuum level; circularly executing the preheating treatment operation for at least n times; wherein n is a positive integer greater than or equal to 1; performing drying operation on the tested battery cell according to the fact that the vacuum value of the baking chamber is a second vacuum level; wherein the first vacuum level is normal pressure, and the first vacuum level is larger than the second vacuum level. The baking and heating time can be shortened, so that the energy consumption is reduced, and the drying efficiency is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of battery technology, and in particular to a method and device for baking a battery cell. Background Art

[0002] The battery cell baking technology is mainly used in the production process of lithium batteries to dry the battery electrodes to ensure electrochemical and safety performance. Baking is a key process in the battery manufacturing process, so the water content inside the battery cell is related to the final performance of the battery cell.

[0003] In the traditional baking process, heating is divided into contact thermal radiation heating and hot air circulation heating. It generally takes a long time for the internal temperature of the battery cell to rise. In the later baking process, the rate of moisture removal from the battery cell is slow, which leads to a longer overall baking time. Summary of the invention

[0004] In order to solve the above technical problems, the present disclosure provides a battery cell baking method and device, including:

[0005] Place the test cell into the baking chamber;

[0006] Performing a preheating treatment operation according to the vacuum value of the baking chamber being the first vacuum level;

[0007] cyclically performing the preheating treatment operation at least n times; wherein n is a positive integer greater than or equal to 1;

[0008] Performing a drying operation on the test battery cell according to the vacuum value of the baking chamber being the second vacuum level;

[0009] Wherein, the first vacuum level is normal pressure, and the first vacuum level is greater than the second vacuum level.

[0010] In some embodiments, the preheating process is performed according to the vacuum value of the baking chamber being the first vacuum level, including:

[0011] Controlling the vacuum pump to evacuate the baking chamber;

[0012] The baking chamber is filled with inert gas to the first vacuum level to perform the preheating treatment operation.

[0013] In some embodiments, the preheating operation includes:

[0014] Controlling the baking chamber to be preheated to a preset temperature and continuing the preheating for a first preset time period;

[0015] The vacuum pump is controlled to evacuate the baking chamber, and an inert gas is filled into the baking chamber to reach the first vacuum level.

[0016] In some embodiments, the drying operation of the test cell according to the vacuum value of the baking chamber being the second vacuum level includes:

[0017] controlling a vacuum pump to evacuate the baking chamber until the vacuum value of the baking chamber reaches a second vacuum value;

[0018] Maintaining the vacuum value in the baking chamber unchanged, and continuing heating for a second preset time;

[0019] The inert gas in the baking chamber is replaced so that the vacuum value in the baking chamber reaches a first vacuum level.

[0020] In some embodiments, after the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0021] The drying operation is performed in a cycle at least m times, wherein m is a positive integer greater than or equal to 2.

[0022] In some embodiments, the battery cell baking device comprises at least one vacuum pump and a plurality of baking chambers, wherein one vacuum pump is connected to at least two of the baking chambers;

[0023] Before the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0024] Controlling the vacuum pump to perform vacuum processing on one of the baking chambers until the vacuum value of the baking chamber reaches a third vacuum value and is maintained for a third preset time;

[0025] Within a third preset time period, controlling the vacuum pump to perform vacuum processing on other baking chambers;

[0026] The third vacuum value is greater than the second vacuum level and less than the first vacuum level.

[0027] In some embodiments, after the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0028] The baking chamber is controlled to maintain the second vacuum level for a time period that satisfies a fourth preset time period.

[0029] In some embodiments, the method further includes: after drying the test cell according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0030] Taking out some test cells in the baking chamber for testing, and maintaining the vacuum value in the baking chamber at the fourth vacuum level;

[0031] The fourth vacuum level is lower than the first vacuum level.

[0032] In a second aspect, the present disclosure provides a battery cell baking device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of any of the battery cell baking methods provided in the first aspect are implemented.

[0033] In some embodiments, further comprising: at least one vacuum pump and a plurality of baking chambers;

[0034] Wherein, one vacuum pump is connected to at least two baking chambers.

[0035] Compared with the prior art, the technical solution provided by the present invention has the following advantages:

[0036] The cell baking method provided by the present disclosure includes placing a test cell into a baking chamber; performing a preheating treatment operation according to a first vacuum level according to the vacuum value of the baking chamber; performing the preheating treatment operation in a cycle at least n times; wherein n is a positive integer greater than or equal to 1; performing a drying operation on the test cell according to a second vacuum level according to the vacuum value of the baking chamber; wherein the first vacuum level is normal pressure, and the first vacuum level is greater than the second vacuum level. Compared with the traditional baking process, the present disclosure performs multiple preheating treatment operations on the baking chamber, and discharges the water vapor generated during the preheating process, thereby achieving the purpose of quickly releasing and discharging the water vapor inside the cell. Avoiding insufficient preheating that causes the water inside the cell to be unable to be discharged, affecting the baking effect of the cell, is conducive to shortening the baking heating time, thereby reducing energy consumption and improving drying efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0039] Figure 1 A schematic diagram of a process of a battery cell baking method provided in an embodiment of the present disclosure;

[0040] Figure 2 A comparative schematic diagram of a moisture test of a battery cell under different baking environments provided in an embodiment of the present disclosure;

[0041] Figure 3A schematic diagram of the structure of a battery cell baking device provided in an embodiment of the present disclosure;

[0042] Figure 4 A schematic structural diagram of another battery cell baking device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0043] In order to more clearly understand the above-mentioned objectives, features and advantages of the present disclosure, the scheme of the present disclosure will be further described below. It should be noted that the embodiments of the present disclosure and the features in the embodiments can be combined with each other without conflict.

[0044] In the following description, many specific details are set forth to facilitate a full understanding of the present disclosure, but the present disclosure may also be implemented in other ways different from those described herein; it is obvious that the embodiments in the specification are only part of the embodiments of the present disclosure, rather than all of the embodiments.

[0045] In order to solve the above problems, the present disclosure provides a method for baking a battery cell. Figure 1 A schematic diagram of a cell baking method provided by an embodiment of the present disclosure, referring to Figure 1 , the cell baking method includes:

[0046] S101, placing the test battery cell into a baking chamber.

[0047] S102, performing a preheating treatment operation according to the vacuum value of the baking chamber being the first vacuum level.

[0048] S103, cyclically executing the preheating treatment operation at least n times; wherein n is a positive integer greater than or equal to 1.

[0049] S104, drying the test battery cell according to the vacuum value of the baking chamber being the second vacuum level;

[0050] Among them, the first vacuum level is normal pressure, and the first vacuum level is greater than the second vacuum level.

[0051] For example, a cell baking device is usually used to bake the test cell. The cell baking device includes a baking chamber and a vacuum pump. The baking chamber is used to place the test cell and heat it up, while the vacuum pump is used to adjust the vacuum level in the baking chamber (which can be understood as a vacuum value or a pressure value. The embodiment of the present disclosure can be understood as a pressure value in the baking chamber). Different vacuum levels require different energy consumption when baking the test cell. For example, the lower the vacuum level, the smaller the pressure value, which belongs to a high vacuum environment, and the temperature and energy required for water vapor evaporation are lower; and the higher the vacuum level, the greater the pressure value, which belongs to a low vacuum environment.

[0052] When baking the test cells in the disclosed embodiment, firstly, multiple test cells are placed in the baking chamber, and the door of the baking chamber is closed when it is full. Then, the baking chamber is preheated. At this time, the vacuum value of the baking chamber can be the first vacuum level, that is, the preheating operation is performed under normal pressure. During the preheating operation, part of the water inside the test cell can be evaporated into the baking chamber. The evaporated water vapor will cause the humidity in the baking chamber to be high, so the water vapor is discharged from the baking chamber, and the vacuum value of the baking chamber is controlled to be the first vacuum level again, and the preheating operation is continued, and the cycle is performed. Among them, the preheating operation is performed at least n times in a cycle; wherein n is a positive integer greater than or equal to 1. For example, each preheating is 40 minutes, and at least two preheating operations are performed to gradually evaporate the water inside the test cell and discharge it from the baking chamber.

[0053] After the preheating stage is completed, the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level. Among them, the second vacuum level is lower than the first vacuum level, for example, the first vacuum level is 98000-103000Pa at normal pressure, and the pressure value of the second vacuum level is lower than normal pressure, for example, the second vacuum level is 15-30Pa, and the vacuum value of the baking chamber is a high vacuum environment when it is the second vacuum level. Drying the test cell in a high vacuum environment is beneficial to reducing energy consumption. In addition, since the preheating treatment operation is performed multiple times, the moisture inside the test cell is fully dried out, and accordingly, the drying operation takes a shorter time, which shortens the baking time of the test cell as a whole, and the drying is more sufficient, thereby improving the drying effect.

[0054] Compared with the traditional baking process, the embodiment of the present disclosure performs multiple preheating treatment operations on the baking chamber and discharges the water vapor generated during the preheating process, thereby achieving the purpose of quickly releasing and discharging the water vapor inside the battery cell. This avoids insufficient preheating that causes the water inside the battery cell to be unable to be discharged, affecting the baking effect of the battery cell, and is conducive to shortening the baking heating time, thereby reducing energy consumption and improving drying efficiency.

[0055] In some embodiments, the preheating treatment operation is performed according to the vacuum value of the baking chamber being the first vacuum level, including:

[0056] Control the vacuum pump to evacuate the baking chamber.

[0057] The baking chamber is filled with inert gas to a first vacuum level to perform a preheating treatment operation.

[0058] Specifically, after the test battery is placed in the baking chamber, the baking chamber is filled with air and is at normal pressure. In order to avoid chemical reactions in the test battery during the baking process, an inert gas is used to replace the air in the baking chamber. First, the vacuum pump is controlled to evacuate the baking chamber, for example, evacuate to 1000Pa and stop, and then fill the baking chamber with inert gas to the first vacuum level to perform a preheating operation. It should be noted that the time to stop the vacuuming can be selected according to actual needs. The embodiment of the present disclosure selects 1000Pa to stop in order to shorten the vacuuming time. This value is only used as an example.

[0059] In some embodiments, the preheat treatment operation includes:

[0060] Controlling the baking chamber to preheat to a preset temperature and continuing for a first preset time;

[0061] The vacuum pump is controlled to evacuate the baking chamber, and an inert gas is filled into the baking chamber to a first vacuum level.

[0062] Specifically, the preheating treatment operation includes controlling the baking chamber to heat up until a preset temperature is reached, such as a preset temperature of 90-110°C, and continuing for a first preset time, such as 1800s-2400s. When the first preset preheating time is met, part of the moisture inside the test battery is evaporated into the baking chamber. The water vapor content in the baking chamber is relatively high, which will affect the subsequent heating effect. Therefore, the vacuum pump is controlled to evacuate the baking chamber to extract the inert gas containing a large amount of water vapor. For example, the vacuuming lasts for 1-30s. After the end, the inert gas is filled into the baking chamber again to the first vacuum level. At this time, a preheating treatment operation is completed. The cyclic preheating treatment operation can be continued later, for example, 1-3 times.

[0063] The embodiment of the present disclosure focuses on the cyclic preheating operation. In each preheating operation, the water vapor produced by baking is discharged and replaced with dry inert gas to perform the preheating operation again, thereby improving the preheating effect and the drying effect of the test battery and reducing the time required for subsequent drying operations. Further, it is beneficial to shorten the overall baking heating time, thereby reducing energy consumption and improving drying efficiency.

[0064] In some embodiments, the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, including:

[0065] Controlling the vacuum pump to perform vacuum processing on the baking chamber until the vacuum value of the baking chamber reaches a second vacuum value;

[0066] Maintaining the vacuum value in the baking chamber unchanged, and continuing heating for a second preset time;

[0067] The inert gas in the baking chamber is replaced so that the vacuum value in the baking chamber reaches the first vacuum level.

[0068] Exemplarily, the preheating stage ends and the drying stage begins. In the drying stage, the test cell is usually baked at high temperature in a high vacuum environment to quickly evaporate the remaining water in the test cell. For example, the vacuum pump is controlled to evacuate the baking chamber until the vacuum value of the baking chamber reaches the second vacuum value, the vacuum value in the baking chamber is kept unchanged, and the heating is continued for the second preset time. When the second preheating time is met, the water vapor content in the baking chamber is relatively high. The vacuum pump can be controlled to evacuate the baking chamber, extract the inert gas containing a large amount of water vapor, and fill the baking chamber with inert gas to the first vacuum level, and the drying operation ends. When the baking chamber is at the first vacuum level, that is, normal pressure, the door of the baking chamber can be opened, and the test cell can be taken out to test the baking effect.

[0069] In some embodiments, after the test battery cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0070] The drying operation is performed in a cycle for at least m times, where m is a positive integer greater than or equal to 2.

[0071] Exemplarily, considering the actual application scenario, the drying operation can be performed multiple times to achieve a better drying effect. After performing a drying operation, the water vapor in the test battery may not be completely released. The test battery cell can be dried again according to the vacuum value of the baking chamber at the second vacuum level, and the drying operation is performed at least m times in a cycle. Wherein, m is a positive integer greater than or equal to 2. For example, after 2-5 cycles of drying operation, the water in the test battery cell is fully evaporated and the baking of the test battery cell is completed.

[0072] The disclosed embodiment performs multiple drying operations, and in each drying operation, the steam produced by baking is discharged and replaced with dry inert gas to perform the drying operation again, thereby improving the drying effect and reducing the time required for subsequent operations. Further, it is beneficial to shorten the overall baking heating time, thereby reducing energy consumption and improving drying efficiency.

[0073] In some embodiments, the battery cell baking device includes at least one vacuum pump and a plurality of baking chambers, wherein one vacuum pump is connected to at least two baking chambers;

[0074] Before drying the test cell according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0075] Controlling the vacuum pump to perform vacuum processing on one of the baking chambers until the vacuum value of the baking chamber reaches a third vacuum value and is maintained for a third preset time period;

[0076] Within a third preset time period, controlling the vacuum pump to perform vacuum processing on other baking chambers;

[0077] The third vacuum value is greater than the second vacuum level and less than the first vacuum level.

[0078] In the embodiment of the present disclosure, the cell baking device used when baking the cell includes at least one vacuum pump and a plurality of baking chambers, and one vacuum pump is connected to at least two baking chambers, that is, each vacuum pump can provide a vacuum environment for at least two baking chambers. However, it should be noted that the vacuum pump cannot provide sufficient vacuum value for two baking chambers at the same time, so usually only one baking chamber is vacuumed at a time.

[0079] Based on the above structure, before the test battery cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the vacuum pump is controlled to perform vacuum treatment on one of the baking chambers until the vacuum value of the baking chamber is the third vacuum value and maintained for the third preset time. Since the second vacuum level is less than the third vacuum level, it takes too long to directly reach the second vacuum level from the first vacuum level, which will affect the normal operation of other baking chambers corresponding to the vacuum pump. Therefore, after the preheating operation is completed, the vacuum value of the baking chamber is adjusted from the first vacuum level to the third vacuum level as a transition, and lasts for the third preset time, for example, 900-1800s. During this period of time, the vacuum pump is controlled to perform vacuum treatment on other baking chambers to avoid affecting the operation of other baking chambers. After the third preset time is over, the vacuum pump is controlled again to perform vacuum treatment on the baking chamber, and its vacuum value is adjusted from the third vacuum level to the second vacuum level. Among them, the third vacuum value is greater than the second vacuum level and less than the first vacuum level, for example, the second vacuum level is 15-30Pa, and the third vacuum level is 100-300Pa.

[0080] In some embodiments, after the test battery cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0081] The baking chamber is controlled to maintain the second vacuum level for a time period that satisfies a fourth preset time period.

[0082] Exemplarily, after the drying operation is completed, the baking chamber can be controlled to continue to maintain the second vacuum level until the duration meets the fourth preset duration, such as 3000-3600s, at which time the entire baking process is completed. This step can avoid the problem of residual moisture in the test battery cell due to the previous drying operation not completely removing the moisture in the test battery cell. By controlling the baking chamber to maintain the second vacuum level, drying can be performed again without replacing the inert gas, which will take away heat and cause heat loss. Therefore, the battery can be further tested to improve the baking effect.

[0083] In some embodiments, the method further includes: after drying the test battery cell according to the vacuum value of the baking chamber being the second vacuum level, the method further includes:

[0084] Take out some test cells in the baking chamber for testing, and keep the vacuum in the baking chamber at the fourth vacuum level;

[0085] The fourth vacuum level is lower than the first vacuum level.

[0086] Exemplarily, after the drying is completed, the vacuum value of the baking chamber is adjusted to normal pressure, the door of the baking chamber is opened, and some test cells in the baking chamber are taken out for testing. There are still test cells in the baking chamber that have not been inspected. In order to avoid affecting their baking effect, the vacuum value in the baking chamber is maintained at the fourth vacuum level. Among them, the fourth vacuum level is lower than the low vacuum level, that is, it is also in a high vacuum environment. In a high vacuum environment, the heat preservation effect is better. The fourth vacuum level can be 300-500Pa. If a lower air pressure value is required, it can also be 15-30Pa, which has a better heat preservation effect.

[0087] The embodiment of the present disclosure mainly performs multiple preheating operations on the baking chamber and discharges the water vapor generated during the preheating process, thereby achieving the purpose of quickly releasing and discharging the water vapor inside the battery cell. The following is an explanation of the specific operation steps using a complete embodiment:

[0088] S201, place the test battery cell into the baking chamber, and close the chamber door after it is full.

[0089] S202, controlling the vacuum pump to evacuate the baking chamber to 1000 Pa, and then filling the baking chamber with inert gas to a first vacuum level.

[0090] S203, controlling the baking chamber to preheat to a preset temperature and continuing for a first preset time, for example, 1800-2400 seconds.

[0091] S204, controlling the vacuum pump to evacuate the baking chamber, for example, maintaining the vacuum for 1-30 seconds, and filling the baking chamber with inert gas to a first vacuum level.

[0092] S205. Execute S203 and S204 in a loop, 1 to 3 times.

[0093] S206, controlling the vacuum pump to perform vacuum processing on the baking chamber until the vacuum value of the baking chamber reaches a third vacuum value and is maintained for a third preset time, for example, 900-1800 seconds.

[0094] S207, controlling the vacuum pump again to evacuate the baking chamber until the vacuum value of the baking chamber reaches a second vacuum value, and maintaining the vacuum value for a second preset time, such as 4500-6000 seconds.

[0095] S208, replacing the inert gas in the baking chamber to make the vacuum value in the baking chamber reach the first vacuum level.

[0096] S209, execute S207 and S208 in a loop, and repeat 2-5 times.

[0097] S210, controlling the baking chamber to maintain the second vacuum level for a time period that satisfies a fourth preset time period, for example, 3000-3600 seconds.

[0098] S211, taking out some test cells in the baking chamber for testing, and maintaining the vacuum value in the baking chamber at the fourth vacuum level.

[0099] Among them, the first vacuum level is normal pressure, 98000-103000Pa; the second vacuum level is 15-30Pa; the third vacuum level is 100-300Pa; the fourth vacuum level is 300-500Pa. In addition, nitrogen can be selected as the inert gas, and the moisture content of nitrogen is ≤0.06g / cm 3 The temperature of the preheating process and the heating process can be 90-110℃.

[0100] It should be noted that the above-mentioned vacuum level, various time durations, temperature and other parameters as well as the type of inert gas can be set according to actual needs, and the inert gas in the embodiments of the present disclosure is only used as an example.

[0101] Optionally, the embodiments of the present disclosure further provide three embodiments of baking the test battery cells using different numbers of preheating treatment operations. By comparing the baking effects of the three embodiments, the beneficial effects brought by the embodiments of the present disclosure can be more intuitively reflected.

[0102] Specifically, in Example 1, the specific steps are as follows:

[0103] S301, placing 864 test cells in a tray into a baking chamber;

[0104] S302, test the preheating of the battery cell, the preheating time is 80-120 minutes, and the preheating temperature rises to 95°C;

[0105] S303, control the vacuum pump to perform vacuum operation, vacuumize to 30-100Pa, and bake for 100-150min;

[0106] S304, replace nitrogen, fill with 60-100KPa nitrogen, and heat with air circulation for 5-10 minutes;

[0107] S305, steps S303 and S304 are repeated 3 times;

[0108] S306, maintaining the pressure at 30-100 Pa until the baking process is completed.

[0109] At the end of the baking process, the test cell was taken out and the moisture content was tested with a Karl Fischer moisture tester to less than 250ppm. The test conditions included: temperature of 170°C, test time of 600s, gas flow rate of 80mL / min, sampling mass of 0.8-1.2g, and relative drift value of 8ug / min.

[0110] In Example 2, a 120Ah lithium iron phosphate short-blade battery cell with a battery cell length of 500 mm was used for testing, and the specific steps are as follows:

[0111] S311, put 864 test cells into the baking chamber.

[0112] S312, test the preheating of the battery cell. The preheating time is 40 minutes and the preheating temperature rises to 90°C.

[0113] S313, control the vacuum pump to perform vacuum operation, vacuum for 10-30 seconds, fill with 100KPa nitrogen, and heat for 5 minutes.

[0114] S314, steps S312 and S313 are cycled once, and preheating is repeated.

[0115] S315. Keep the vacuum environment dry, evacuate to 30-100Pa, and bake for 120 minutes.

[0116] S316, carry out nitrogen replacement, fill in 60-100KPa nitrogen, and heat with air circulation for 10 minutes.

[0117] S317, steps S315 and S316 are looped three times.

[0118] S318, maintain the pressure at 30-100Pa until the baking process is completed.

[0119] At the end of the baking process, the test cell was taken out and the moisture content was tested with a Karl Fischer moisture tester to less than 250ppm. The test conditions included: temperature of 170°C, test time of 600s, gas flow rate of 80mL / min, sampling mass of 0.8-1.2g, and relative drift value of 8ug / min.

[0120] In Example 3, a 150Ah lithium iron phosphate short-blade battery cell with a battery cell length of 600 mm was used for testing, and the specific steps are as follows:

[0121] S321, put 864 test cells into the baking chamber.

[0122] S322, test the preheating of the battery cell. The preheating time is 40 minutes and the preheating temperature rises to 90°C.

[0123] S323. Control the vacuum pump to perform vacuum operation for 10-30 seconds, fill with 100KPa nitrogen, and heat for 5 minutes.

[0124] S324, steps S322, and S323 are cycled twice to repeat preheating.

[0125] S325. Keep the vacuum environment dry, evacuate to 30-100Pa, and bake for 100 minutes.

[0126] S326, carry out nitrogen replacement, fill in 60-100KPa nitrogen, and heat with air circulation for 10 minutes.

[0127] S327, steps S325 and S326 are looped three times.

[0128] S328, maintain the pressure at 30-100Pa until the baking process is completed.

[0129] At the end of the baking process, the test cell was taken out and the moisture content was tested with a Karl Fischer moisture tester to less than 250ppm. The test conditions included: temperature of 170°C, test time of 600s, gas flow rate of 80mL / min, sampling mass of 0.8-1.2g, and relative drift value of 8ug / min.

[0130] Figure 2 A comparative schematic diagram of a moisture test of a battery cell under different baking environments provided by an embodiment of the present disclosure, referring to Figure 2 , the horizontal axis represents the battery cell groups, each group includes multiple test batteries, and the vertical axis represents the average water content of the test batteries in each group. Among them, L1 represents the test results of implementation 1, L2 represents the test results of implementation 2, and L3 represents the test results of implementation 3. It can be seen from the figure that the water content of implementation 1 is the largest, and the water content of implementation 3 is the smallest. During the baking process, implementation 1 only performs one preheating treatment operation, implementation 2 performs two preheating treatment operations, and implementation 3 performs three preheating treatment operations. Therefore, it can be seen that the baking effects of implementation 2 and implementation 3 are better than those of implementation 1. As the number of preheating treatments increases, the better the drying effect of the test battery cells, the lower the water content. It should be noted that the above embodiments are only a comparison result provided by the present disclosure, and the test time, air pressure value, number of cycles, etc. will affect the baking effect.

[0131] The present disclosure also provides a battery cell baking device, Figure 3 This is a schematic diagram of a battery cell baking device provided by an embodiment of the present disclosure, referring to Figure 3 The battery cell baking device includes a processor 401 and a memory 402. The memory 402 stores a computer program. When the processor 401 executes the computer program, the steps of the battery cell baking method in any one of the above embodiments are implemented.

[0132] Specifically, Figure 3 As shown, the cell baking device includes at least one processor 401, at least one memory 402 and at least one communication interface 403. The various components in the cell baking device are coupled together through a bus system 404. The communication interface 403 is used for information transmission between external devices. It can be understood that the bus system 404 is used to achieve connection and communication between these components. In addition to the data bus, the bus system 404 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, Figure 3 Various buses are labeled as bus system 404 .

[0133] It is understood that the memory 402 in this embodiment may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. In some implementations, the memory 402 stores the following elements: executable units or data structures, or their subsets, or their extended set operating systems and applications. In the disclosed embodiment, the processor 401 executes the steps of each embodiment of the method provided in the disclosed embodiment by calling the program or instruction stored in the memory 402.

[0134] The method provided in the embodiment of the present disclosure can be applied to the processor 401, or implemented by the processor 401. The processor 401 can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor 401 or an instruction in the form of software. The above-mentioned processor 401 can be a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), a field programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc.

[0135] The steps of the method provided in the embodiment of the present disclosure can be directly embodied as being executed by a hardware decoding processor, or can be executed by a combination of hardware and software units in the decoding processor. The software unit can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 402, and the processor 401 reads the information in the memory 402 and completes the steps of the method in combination with its hardware.

[0136] Figure 4 A schematic diagram of the structure of another battery cell baking device provided in the embodiment of the present disclosure, referring to Figure 4 The battery cell baking equipment further includes: at least one vacuum pump 50 and a plurality of baking chambers 60 ; wherein one vacuum pump 50 is connected to at least two baking chambers 60 .

[0137] For example, Figure 4 The vacuum pump 50 includes four vacuum pumps, namely vacuum pump 51, vacuum pump 52, vacuum pump 53 and vacuum pump 54, and fourteen baking chambers (the numbers can refer to the attached figure). Among them, vacuum pump 51 is connected to baking chambers No. 61-64 to meet their vacuum requirements; vacuum pump 52 is connected to baking chambers No. 65-68 to meet their vacuum requirements; vacuum pump 53 is connected to baking chambers No. 69-71 to meet their vacuum requirements, and vacuum pump 54 is connected to baking chambers No. 72-74 to meet their vacuum requirements. Through this structure, the priority of the vacuum pump can be reasonably allocated to avoid the vacuum pump resources being occupied by adjacent ovens for a long time, or being idle for a long time. The vacuum pump 50 can make the baking chamber form different vacuum levels, and different vacuum levels can have priorities. For example, it is determined according to the pressure value. The smaller the pressure value, the longer the vacuuming time, and the lower the priority. Therefore, when multiple baking chambers corresponding to a vacuum pump 50 all need to be vacuumed, the priority of the vacuum level will be used to decide which baking chamber's vacuum demand will be met first, so as to reasonably allocate vacuum pump resources and avoid long waiting time and time consumption.

[0138] The embodiments of the present disclosure also provide a computer-readable storage medium, which stores a program or instruction, and the program or instruction enables a computer to execute the steps of any method in the above method embodiments.

[0139] The computer-readable storage medium provided in the embodiments of the present disclosure can execute the steps of any one of the methods in the above-mentioned battery cell baking method embodiments, and thus can also achieve the same technical effect as the above-mentioned battery cell baking method.

[0140] In addition to the above-mentioned method and battery cell baking device, the embodiments of the present application may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the method steps of various embodiments of the present application.

[0141] The computer program product may be written in any combination of one or more programming languages ​​to write program code for performing the operations of the embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0142] In addition, the embodiments of the present application may also be a computer-readable storage medium on which computer program instructions are stored. When the computer program instructions are executed by the processor 401, the processor 401 executes the method steps of various embodiments of the present application.

[0143] Computer readable storage media can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0144] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0145] The above description is only a specific embodiment of the present disclosure, so that those skilled in the art can understand or implement the present disclosure. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to the embodiments described herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for baking a battery cell, characterized in that: include: Place the test cell into the baking chamber; Performing a preheating treatment operation according to the vacuum value of the baking chamber being the first vacuum level; cyclically performing the preheating treatment operation at least n times; wherein n is a positive integer greater than or equal to 1; Performing a drying operation on the test battery cell according to the vacuum value of the baking chamber being the second vacuum level; Wherein, the first vacuum level is normal pressure, and the first vacuum level is greater than the second vacuum level.

2. The battery cell baking method according to claim 1, characterized in that: The preheating treatment operation is performed according to the vacuum value of the baking chamber being the first vacuum level, comprising: Controlling the vacuum pump to perform vacuum treatment on the baking chamber; The baking chamber is filled with inert gas to the first vacuum level to perform the preheating treatment operation.

3. The battery cell baking method according to claim 1, characterized in that: The preheating treatment operation includes: Controlling the baking chamber to be preheated to a preset temperature and continuing the preheating for a first preset time period; The vacuum pump is controlled to evacuate the baking chamber, and an inert gas is filled into the baking chamber to reach the first vacuum level.

4. The battery cell baking method according to claim 1, characterized in that: The drying operation of the test cell according to the vacuum value of the baking chamber being the second vacuum level includes: controlling a vacuum pump to evacuate the baking chamber until the vacuum value of the baking chamber reaches a second vacuum value; Maintaining the vacuum value in the baking chamber unchanged, and continuing heating for a second preset time; The inert gas in the baking chamber is replaced so that the vacuum value in the baking chamber reaches a first vacuum level.

5. The battery cell baking method according to claim 1, characterized in that: After the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes: The drying operation is performed in a cycle at least m times, wherein m is a positive integer greater than or equal to 2.

6. The battery cell baking method according to claim 1, characterized in that: The battery cell baking equipment comprises at least one vacuum pump and a plurality of baking chambers, wherein one vacuum pump is connected to at least two of the baking chambers; Before the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes: Controlling the vacuum pump to perform vacuum processing on one of the baking chambers until the vacuum value of the baking chamber reaches a third vacuum value and is maintained for a third preset time; Within a third preset time period, controlling the vacuum pump to perform vacuum processing on other baking chambers; The third vacuum value is greater than the second vacuum level and less than the first vacuum level.

7. The battery cell baking method according to claim 1, characterized in that: After the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes: The baking chamber is controlled to maintain the second vacuum level for a time period that satisfies a fourth preset time period.

8. The battery cell baking method according to claim 1, characterized in that: Also includes: After the test cell is dried according to the vacuum value of the baking chamber being the second vacuum level, the method further includes: Taking out some test cells in the baking chamber for testing, and maintaining the vacuum value in the baking chamber at the fourth vacuum level; The fourth vacuum level is lower than the first vacuum level.

9. A battery cell baking device, characterized in that: The invention comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the battery cell baking method according to any one of claims 1 to 8 when executing the computer program.

10. The battery cell baking device according to claim 9, characterized in that: Also includes: at least one vacuum pump and a plurality of baking chambers; Wherein, one vacuum pump is connected to at least two baking chambers.

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