Battery cell processing method, battery cell processing device, and battery

Abstract

The present invention relates to the technical field of batteries, and particularly relates to a battery cell processing method, a battery cell processing device, and a battery. The battery cell processing method comprises the following steps: placing a battery cell in a reaction chamber; and performing excitation or introduction in the reaction chamber to form plasma which flows in a preset direction, wherein the preset direction comprises a direction in which the plasma flows through the battery cell, and using the flowing plasma to process the battery cell. The present invention is conducive to ameliorating the problems of low injection efficiency and low infiltration efficiency of an electrolyte.

Description

Battery cell processing method, battery cell processing equipment and battery

[0001] This application claims priority to Chinese patent application CN2023109286592, filed on July 25, 2023, entitled “Battery cell processing method, battery cell processing equipment and battery”. The entire contents of the above Chinese patent application are incorporated into this application by reference. Technical Field

[0002] The present invention relates to the technical field of batteries, and in particular to a method for processing a battery cell, a battery cell processing device, and a battery. Background Art

[0003] The battery cell is an important component in the battery. When assembling the battery, it is usually necessary to inject electrolyte into the battery shell where the battery cell is assembled. This process is one of the key process sections in assembling the battery.

[0004] Currently, there are still problems such as low electrolyte injection efficiency and long electrolyte soaking time for battery cells.

[0005] Summary of the Invention

[0006] Based on this, the present invention provides a battery cell processing method, a battery cell processing device and a battery to improve the problems of low electrolyte injection efficiency and low infiltration efficiency.

[0007] The first aspect of the present invention provides a method for processing a battery cell, and the technical solution thereof is as follows:

[0008] A method for processing a battery cell comprises the following steps:

[0009] Placing the battery cell in the reaction chamber;

[0010] A plasma is excited or introduced into the reaction chamber to flow along a preset direction, wherein the preset direction includes a direction of flowing through the battery cell, and the battery cell is processed by utilizing the flowing plasma.

[0011] In some embodiments, exciting the reaction chamber to form plasma flowing along a predetermined direction includes the following steps:

[0012] Connect the positive and negative tabs of the battery cell to electricity to form an electric field;

[0013] A preset gas is introduced into the reaction chamber to form a flow along the preset direction. When the preset gas flows through the battery core, it is excited by the electric field to form plasma that flows along the preset direction.

[0014] In some embodiments, introducing the predetermined gas into the reaction chamber to form a flow along the predetermined direction includes the following steps:

[0015] A preset gas is input into the reaction chamber, and the preset gas is made to flow along the preset direction.

[0016] In some embodiments, introducing plasma into the reaction chamber to form a flow along a predetermined direction includes the following steps:

[0017] inputting plasma into the reaction chamber;

[0018] The plasma entering the reaction chamber is caused to flow along a preset direction.

[0019] In some embodiments, the battery cell includes stacked positive electrode sheets, separators and negative electrode sheets, and the direction of flow through the battery cell includes the direction of flowing through the pores of the positive electrode sheets, the pores of the separators and the pores of the negative electrode sheets in sequence and / or the direction of flowing through the pores of the negative electrode sheets, the pores of the separators and the pores of the positive electrode sheets in sequence.

[0020] The second aspect of the present invention provides a battery cell processing device, the technical solution of which is as follows:

[0021] A battery cell processing device comprises a reaction chamber, wherein the reaction chamber is used to place a battery cell and can stimulate or introduce plasma in the reaction chamber to flow along a preset direction, wherein the preset direction includes a direction flowing through the battery cell.

[0022] In some embodiments, two electrodes are further provided in the reaction chamber, and the two electrodes are respectively used to electrically connect to the positive electrode tab and the negative electrode tab of the battery cell to form an electric field to excite the preset gas flowing through the battery cell to form a plasma flowing along the preset direction.

[0023] In some embodiments, a first ventilation system is further included, wherein the first ventilation system is connected to the reaction chamber and is used to input a preset gas into the reaction chamber and make the preset gas flow along the preset direction.

[0024] In some embodiments, a plasma generating device is further included, wherein a plasma output end of the plasma generating device is in communication with the reaction chamber, and the plasma generating device is used to input plasma into the reaction chamber;

[0025] It also includes a second ventilation system, which is communicated with the reaction chamber and is used to make the plasma entering the reaction chamber flow along a preset direction.

[0026] A third aspect of the present invention provides a battery comprising a modified battery cell, wherein the modified battery cell is obtained by the above-mentioned method.

[0027] The present invention has the following beneficial effects:

[0028] The present invention first uses plasma to treat the battery cell, in order to reduce the contact angle of the electrolyte on the battery cell surface, thereby improving the efficiency of electrolyte injection and the efficiency of the battery cell soaking into the electrolyte. Further research by the inventors found that, compared to treating the battery cell with plasma in a disordered state, treating the battery cell with plasma in an orderly flow state (flowing in a preset direction) significantly improves the flowability of the electrolyte within the battery cell, which helps further shorten the time for electrolyte injection and the time it takes for the battery cell to soak into the electrolyte. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention and to provide a more complete understanding of the present invention and its beneficial effects, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0030] FIG1 is a schematic structural diagram of a battery cell processing device of Example 1;

[0031] FIG2 is a schematic structural diagram of a cell processing device of Example 2;

[0032] FIG3 is a schematic structural diagram of a cell processing device of Example 3;

[0033] FIG4 is a schematic structural diagram of the battery cell processing equipment of Example 4. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below with reference to specific embodiments. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the present disclosure.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0036] the term

[0037] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0038] In the present invention, the selection range of "and / or", "or / and", and "and / or" includes any one of two or more related listed items, and also includes any and all combinations of the related listed items, and the said any and all combinations include any combination of two related listed items, any more related listed items, or all related listed items. It should be noted that when at least three items are connected by at least two conjunctions selected from "and / or", "or / and", and "and / or", it should be understood that the technical solution undoubtedly includes technical solutions connected by "logical and" and technical solutions connected by "logical or". For example, "A and / or B" includes three parallel solutions of A, B and A+B. For example, the technical solution of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (that is, the technical solution of all being connected by "logical OR"), and also includes any and all combinations of A, B, C, and D, that is, the combination of any two or any three of A, B, C, and D, and also includes the four-item combination of A, B, C, and D (that is, the technical solution of all being connected by "logical AND").

[0039] In the present invention, "plurality", "multiple", "multiple times", "multiple", etc., unless otherwise specified, refer to a number greater than or equal to 2. For example, "one or more" means one or more than or equal to two.

[0040] In the present invention, references to "combinations thereof", "any combination thereof", "any combination thereof" and the like include all suitable combinations of any two or more of the listed items.

[0041] In the present invention, the “suitable” mentioned in “suitable combination”, “suitable method”, “any suitable method”, etc. shall be based on the ability to implement the technical solution of the present invention, solve the technical problem of the present invention, and achieve the expected technical effect of the present invention.

[0042] In the present invention, “preferred”, “better”, “more preferred” and “suitable” are only used to describe implementation methods or examples with better effects, and it should be understood that they do not constitute a limitation on the scope of protection of the present invention.

[0043] In the present invention, the terms “further”, “further”, “particularly”, etc. are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present invention.

[0044] In this disclosure, the terms "optionally," "optional," and "optional" are optional and refer to either option, i.e., to the selection of either option from the two parallel options of "optional" or "optional." If multiple "optional" terms appear in a technical solution, each "optional" term is independent unless otherwise specified and there are no conflicts or constraints.

[0045] In the present invention, in the "first aspect," "second aspect," "third aspect," "fourth aspect," etc., the terms "first," "second," "third," "fourth," etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or quantity, nor as implicitly indicating the importance or quantity of the technical features indicated. Furthermore, "first," "second," "third," "fourth," etc. serve only as non-exhaustive enumeration and description and should be understood not to constitute a closed-ended limitation on quantity.

[0046] In the present invention, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0047] In the present invention, when referring to a numerical interval (i.e., a numerical range), unless otherwise specified, the optional numerical distribution is considered continuous within the above numerical interval and includes the two numerical endpoints of the numerical range (i.e., the minimum value and the maximum value), as well as each numerical value between the two numerical endpoints. Unless otherwise specified, when a numerical interval refers only to integers within the numerical interval, it includes the two endpoint integers of the numerical range, as well as each integer between the two endpoints. In this article, it is equivalent to directly listing each integer, such as t is an integer selected from 1 to 10, indicating that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be merged. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges included therein.

[0048] The temperature parameters in the present invention, unless otherwise specified, may be either constant temperature or fluctuating within a certain temperature range. It should be understood that the constant temperature treatment allows for temperature fluctuations within the precision range of the instrument control. Fluctuations within ranges such as ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are permitted.

[0049] In the present invention, when it comes to percentage content, unless otherwise specified, for solid-liquid mixing and solid-solid mixing, it refers to mass percentage, and for liquid-liquid mixing, it refers to volume percentage.

[0050] In the present invention, when referring to percentage concentration, unless otherwise specified, it refers to the final concentration. The final concentration refers to the percentage of the added component in the system after the addition of the component.

[0051] To improve electrolyte injection efficiency, there are currently two main methods: one is to increase the external injection pressure of the injection machine, thereby improving injection efficiency; the other is to reduce the pressure inside the injection machine's cavity, creating a pressure difference between the inside and outside of the battery cell, thereby improving injection efficiency. Different from the above-mentioned external means to improve injection efficiency, one embodiment of the present invention provides a battery cell processing method, which addresses the problems of low electrolyte injection efficiency and low electrolyte infiltration efficiency from the perspective of modifying the battery cell.

[0052] In this embodiment, the method for processing the battery cell includes the following steps:

[0053] Placing the battery cell in the reaction chamber;

[0054] A plasma is excited or introduced into the reaction chamber to flow along a preset direction, wherein the preset direction includes a direction of flowing through the battery cell, and the battery cell is processed by utilizing the flowing plasma.

[0055] It can be understood that the battery cell may include a positive electrode sheet, a separator, a negative electrode sheet, a positive electrode tab and a negative electrode tab, wherein the positive electrode sheet, the separator and the negative electrode sheet are stacked in sequence, the positive electrode tab is connected to the positive electrode sheet, and the negative electrode tab is connected to the negative electrode sheet. The positive electrode sheet of the battery cell can be one or more, each positive electrode sheet can be led out through each positive electrode tab, and each positive electrode tab is welded together, and each negative electrode sheet can be led out through each negative electrode tab, and each negative electrode tab is welded together.

[0056] Optionally, the battery cell comprises a stacked positive electrode sheet, a separator, and a negative electrode sheet, wherein the positive electrode sheet, the separator, and the negative electrode sheet all have pores, and plasma can flow through the pores to pass through the battery cell.

[0057] Optionally, the direction of flowing through the battery cell includes the direction of flowing through the pores of the positive electrode sheet, the pores of the diaphragm and the pores of the negative electrode sheet in sequence and / or the direction of flowing through the pores of the negative electrode sheet, the pores of the diaphragm and the pores of the positive electrode sheet in sequence.

[0058] It can be understood that the battery cell can be a cylindrical battery cell, a blade-shaped battery cell, a square battery cell or other special-shaped battery cells, and the battery cell can be formed by winding or laminating methods.

[0059] In this embodiment, plasma flowing along a preset direction may be excited in the reaction chamber, or plasma flowing along a preset direction may be introduced into the reaction chamber.

[0060] In the first mode, a plasma is excited in the reaction chamber to form a flow in a predetermined direction, which includes the following steps:

[0061] Connect the positive and negative tabs of the battery cell to electricity to form an electric field;

[0062] A preset gas is introduced into the reaction chamber to form a flow along the preset direction. When the preset gas flows through the battery core, it is excited by the electric field to form plasma that flows along the preset direction.

[0063] Plasma is an ionized gaseous substance composed of positive and negative ions generated by the ionization of atoms and atomic groups stripped of some of their electrons. In this embodiment, when the predetermined gas flows through the battery cell, it is located within the electric field and excited by the electric field to form a plasma. The flow direction of the predetermined gas before and after the excitation remains unchanged. Therefore, the excited plasma flows in the direction of the predetermined gas flow before the excitation, thereby treating the battery cell.

[0064] Optionally, the preset gas is selected from air, nitrogen, argon, oxygen, hydrogen or a combination thereof.

[0065] Optionally, the step of introducing a preset gas into the reaction chamber to form a flow along the preset direction comprises the following steps:

[0066] A preset gas is input into the reaction chamber, and the preset gas is made to flow along the preset direction.

[0067] Optionally, the reaction chamber is a vacuum reaction chamber.

[0068] The preset gas can be introduced into the vacuum reaction chamber at a certain pressure, for example, at a pressure of 1 Pa to 100,000 Pa.

[0069] In this embodiment, a first ventilation system may be provided, connected to the reaction chamber, and gas is introduced into and extracted from the reaction chamber through the first ventilation system, so that the preset gas flows along the preset direction.

[0070] In the second mode, a plasma flowing in a predetermined direction is introduced into the reaction chamber, which includes the following steps:

[0071] inputting plasma into the reaction chamber;

[0072] The plasma entering the reaction chamber is caused to flow along a preset direction.

[0073] Optionally, the reaction chamber is a vacuum reaction chamber.

[0074] The plasma can be formed by introducing gas into the vacuum reaction chamber at a certain pressure, for example, at a pressure of 1 Pa to 100,000 Pa.

[0075] In this embodiment, a plasma generating device may be provided, and a plasma output end of the plasma generating device is connected to the reaction chamber, so that plasma is input into the reaction chamber through the plasma generating device.

[0076] In this embodiment, a second ventilation system may be provided, and the second ventilation system is connected to the reaction chamber. Gas is introduced into the reaction chamber and gas is extracted from the reaction chamber through the second ventilation system, so that the plasma flows along the preset direction.

[0077] Optionally, in the first or second manner, the time for treating the battery cell with the flowing plasma can be adjusted according to the battery process, for example, the treatment time can be 1 second to 1 hour, such as 30 seconds, 1 minute, 10 minutes, 50 minutes, etc.

[0078] This embodiment first uses plasma to treat the battery cell in order to reduce the contact angle of the electrolyte on the surface of the battery cell, thereby improving the efficiency of electrolyte injection and the efficiency of the battery cell soaking in the electrolyte. Through further research by the inventors, it was found that when the plasma is in an orderly flow state (flowing in a preset direction) and the battery cell is treated, the fluidity of the electrolyte inside the battery cell can be significantly improved, which is conducive to further shortening the time of electrolyte injection and the time of battery cell soaking in the electrolyte.

[0079] One embodiment of the present invention also provides a battery cell processing device, including a reaction chamber, which is used to place the battery cell and can excite or introduce plasma in the reaction chamber to flow along a preset direction, wherein the preset direction includes the direction of flowing through the battery cell.

[0080] In this embodiment, plasma flowing along a preset direction may be excited in the reaction chamber, or plasma flowing along a preset direction may be introduced into the reaction chamber.

[0081] In the first mode, plasma is excited in the reaction chamber to form a flow in a predetermined direction. In this case, two electrodes are also provided in the reaction chamber, and the two electrodes are respectively used to electrically connect to the positive and negative tabs of the battery cell to form an electric field to excite a predetermined gas flowing through the battery cell to form a plasma flowing in the predetermined direction.

[0082] Optionally, the cell processing device of this embodiment further includes a radio frequency power supply, which is connected to the two electrodes to form an alternating electric field between the two electrodes. Optionally, the frequency of the radio frequency power supply can be 10 Hz to 16 Hz, for example, 13.56 Hz.

[0083] Optionally, the battery cell processing equipment of this embodiment further includes a first ventilation system, which is connected to the reaction chamber and is used to input a preset gas into the reaction chamber and make the preset gas flow along the preset direction.

[0084] 1 , in Example 1, a cell processing device 01 includes a reaction chamber 10 , a first electrode 11 , a second electrode 12 , a radio frequency power supply 13 , and a first ventilation system 14 ;

[0085] The first electrode 11 and the second electrode 12 are disposed in the reaction chamber 10 and connected to a radio frequency power source 13 outside the reaction chamber. The reaction chamber 10 is provided with a vent, and the first ventilation system 14 is connected to the reaction chamber 10 through the vent.

[0086] A battery cell 15 is provided, which includes a stacked positive electrode sheet, a separator and a negative electrode sheet. When the battery cell processing equipment of this example is used to process the battery cell 15, referring to Figure 1, the battery cell 15 can be placed in a reaction chamber 10, and the positive electrode tab and the negative electrode tab of the battery cell 15 are electrically connected to the first electrode 11 and the second electrode 12 respectively. The first ventilation system 14 provides a preset gas, and by introducing air into the reaction chamber and extracting air from the reaction chamber, the preset gas first flows through the pores of the positive electrode sheet, the pores of the separator and the pores of the negative electrode sheet of the battery cell 15 in sequence; and then flows through the pores of the negative electrode sheet, the pores of the separator and the pores of the positive electrode sheet of the battery cell 15 in sequence.

[0087] Optionally, the number of the vents can be 1 or more. When the number of the vents is 2, one can be used as an air inlet and the other can be used as an air outlet.

[0088] Optionally, the first ventilation system may include two first sub-ventilation systems, one of which is for supplying air into the reaction chamber, and the other is for extracting air from the reaction chamber.

[0089] In the second mode, plasma is introduced into the reaction chamber to form a flow in a preset direction. In this case, the reaction chamber also includes a plasma generator, the plasma output end of the plasma generator is connected to the reaction chamber, and the plasma generator is used to input plasma into the reaction chamber;

[0090] The reaction chamber further includes a second ventilation system, which is communicated with the reaction chamber and is used to allow the plasma entering the reaction chamber to flow along a preset direction.

[0091] Optionally, the reaction chamber is provided with a vent, and the plasma generating device and the second ventilation device are connected to the reaction chamber through the vent.

[0092] 2 , in Example 2, the cell processing device 02 includes a reaction chamber 20 , a first electrode 21 and a second electrode 22 , a radio frequency power supply 23 , a second ventilation system 24 , and a plasma generating device 25 ;

[0093] The first electrode 21 and the second electrode 22 are disposed in the reaction chamber 20 and connected to a radio frequency power source 23 outside the reaction chamber. The reaction chamber 20 is provided with a vent, through which the second ventilation system 24 and the plasma generator 25 are both connected to the reaction chamber 20.

[0094] A battery cell 26 is provided, which includes a stacked positive electrode sheet, a separator and a negative electrode sheet. When the battery cell processing equipment of this example is used to process the battery cell 26, referring to Figure 2, the battery cell 26 can be placed in the reaction chamber 20, and the positive electrode tab and the negative electrode tab of the battery cell 26 are electrically connected to the first electrode 21 and the second electrode 22 respectively. The plasma generating device 25 inputs plasma into the reaction chamber 20, and the second ventilation system 24 allows the plasma entering the reaction chamber to first flow through the pores of the positive electrode sheet, the pores of the separator and the pores of the negative electrode sheet of the battery cell 26 in sequence by introducing air into the reaction chamber and exhausting air from the reaction chamber; and then flows through the pores of the negative electrode sheet, the pores of the separator and the pores of the positive electrode sheet of the battery cell 26 in sequence.

[0095] Optionally, the number of the vents can be one or more. When the number of the vents is two, one of them can be used as an air inlet and the other can be used as an air outlet.

[0096] 3 , in Example 3, the cell processing device 03 includes a reaction chamber 30 , a first electrode 31 and a second electrode 32 , a radio frequency power supply 33 , a second ventilation system 34 and a plasma generating device 35 ;

[0097] A first electrode 31 and a second electrode 32 are disposed within the reaction chamber 30 and connected to a radio frequency power source 33 outside the reaction chamber. The reaction chamber 30 is provided with an air inlet and an air outlet. A second ventilation system 34 is connected to the reaction chamber 30 by connecting to the air inlet and the air outlet, respectively. The plasma generator 25 is connected to the reaction chamber 30 through the air inlet.

[0098] A battery cell 36 is provided, which includes a stacked positive electrode sheet, a separator and a negative electrode sheet. When the battery cell processing equipment of this example is used to process the battery cell 36, referring to Figure 3, the battery cell 36 can be placed in a reaction chamber 30, and the positive electrode tab and the negative electrode tab of the battery cell 36 are electrically connected to the first electrode 31 and the second electrode 32 respectively. The plasma generating device 35 inputs plasma into the reaction chamber 30, and the second ventilation system 34 allows the plasma entering the reaction chamber to flow through the pores of the positive electrode sheet, the pores of the separator and the pores of the negative electrode sheet of the battery cell 36 in sequence by introducing air into the reaction chamber and exhausting air from the reaction chamber; or flows through the pores of the negative electrode sheet, the pores of the separator and the pores of the positive electrode sheet of the battery cell 36 in sequence.

[0099] Optionally, the second ventilation system may include two second sub-ventilation systems, wherein one second sub-ventilation system takes air into the reaction chamber, and the other second sub-ventilation system draws air from the reaction chamber.

[0100] 4 , in Example 4, the cell processing device 04 includes a reaction chamber 40, a first electrode 41 and a second electrode 42, a radio frequency power supply 43, a second sub-one ventilation system 441, a second sub-two ventilation system 442, and a plasma generating device 45;

[0101] A first electrode 41 and a second electrode 42 are disposed within a reaction chamber 40 and connected to a radio frequency power source 43 outside the reaction chamber. The reaction chamber 40 is provided with two vents. A first ventilation system 44 communicates with the reaction chamber 40 by connecting to the two vents, respectively. A plasma generator 45 communicates with the reaction chamber 40 through one vent.

[0102] A battery cell 46 is provided, which includes a stacked positive electrode sheet, a diaphragm and a negative electrode sheet. When the battery cell processing equipment of this example is used to process the battery cell 46, referring to Figure 4, the battery cell 46 can be placed in a reaction chamber 40, and the positive electrode tab and the negative electrode tab of the battery cell 46 are electrically connected to the first electrode 41 and the second electrode 42 respectively. The plasma generating device 45 inputs plasma into the reaction chamber 40, and the second sub-one ventilation system 441 and the second sub-two ventilation system 442 allow air to enter the reaction chamber and exhaust air from the reaction chamber, so that the plasma entering the reaction chamber first flows through the pores of the positive electrode sheet, the pores of the diaphragm and the pores of the negative electrode sheet of the battery cell 46 in sequence; and then flows through the pores of the negative electrode sheet, the pores of the diaphragm and the pores of the positive electrode sheet of the battery cell 46 in sequence.

[0103] It can be understood that in the above examples 1 to 4, the top and bottom of the reaction chamber are not in contact with the battery cells. In other examples, the top and bottom of the reaction chamber may be in contact with the battery cells. In this case, it is easier to control the flow direction of the preset gas or plasma.

[0104] One embodiment of the present invention further provides a modified battery cell obtained by the above method. The modified battery cell has a small contact angle with the electrolyte, and the electrolyte has good fluidity and wettability inside the battery cell.

[0105] One embodiment of the present invention further provides a battery, comprising a modified battery cell, wherein the modified battery cell is obtained by the above-mentioned method.

[0106] It can be understood that one or more modified battery cells can be installed inside the battery shell.

[0107] In this embodiment, the battery cell is assembled in the battery shell. After the assembly is completed, the battery shell is provided with an opening, and the electrolyte is injected along the opening.

[0108] Optionally, the material of the battery shell is selected from stainless steel, aluminum, aluminum-plastic film or a combination thereof.

[0109] In this embodiment, after the modified battery cell is placed in the shell, during the electrolyte injection process, the electrolyte injection efficiency and the battery cell infiltration efficiency are high.

[0110] Optionally, after injecting the electrolyte, the process further includes aging, formation and other steps to prepare the battery.

[0111] The battery of this embodiment has good electrochemical performance.

[0112] The following is further described in conjunction with specific examples and comparative examples. Unless otherwise specified, the raw materials involved in the following specific examples and comparative examples can be sourced from commercial sources. The instruments used can be sourced from commercial sources unless otherwise specified. The processes involved can be selected conventionally by those skilled in the art unless otherwise specified.

[0113] The positive electrode sheet is aluminum foil with a positive electrode active layer on both sides. The positive electrode active layer materials include lithium iron phosphate, polyvinylidene fluoride, and carbon nanotubes. The separator is polyethylene. The negative electrode sheet is copper foil with a negative electrode active layer on both sides. The negative electrode active layer materials include graphite, sodium carboxymethyl cellulose, and carbon nanotubes. The electrolyte is a carbonate solution containing lithium hexafluorophosphate.

[0114] Example 1

[0115] This embodiment provides a method for processing a battery cell, a modified battery cell, a battery, and a method for preparing the same, and the steps are as follows:

[0116] Step 100: stack the positive electrode sheet, the separator and the negative electrode sheet in sequence to prepare a battery cell.

[0117] Step 200, referring to FIG1 , a battery cell 15 is placed in a reaction chamber 10, and the positive electrode tab and the negative electrode tab of the battery cell 15 are electrically connected to a first electrode 11 and a second electrode 12 disposed in the reaction chamber 10, respectively. The first electrode 11 and the second electrode 12 are connected to a radio frequency power supply 13 outside the reaction chamber, and the first ventilation system 14 is connected to the reaction chamber through the vent of the reaction chamber.

[0118] Step 300, the reaction chamber is evacuated, and oxygen is continuously introduced into the reaction chamber through the first ventilation system 14 so that the oxygen first flows through the pores of the positive electrode sheet, the pores of the diaphragm, and the pores of the negative electrode sheet of the battery cell 15 in sequence, and then oxygen is continuously extracted from the reaction chamber; the oxygen is made to flow through the pores of the negative electrode sheet, the pores of the diaphragm, and the pores of the positive electrode sheet of the battery cell 15 in sequence, and the frequency of the radio frequency power supply is set to 13.56 Hz, and the oxygen located between the electric field is excited to form a plasma, forming a plasma that first flows through the pores of the positive electrode sheet, the pores of the diaphragm, and the pores of the negative electrode sheet of the battery cell 15 in sequence, and then flows through the pores of the negative electrode sheet, the pores of the diaphragm, and the pores of the positive electrode sheet of the battery cell 15 in sequence, and maintains discharge for 40 seconds.

[0119] Step 400: exhaust the gas and take out the battery cell after the plasma treatment.

[0120] Step 500: Assemble the battery cell into the battery case, then inject 70 g of electrolyte through the opening of the battery case, and record the total injection time. The results are shown in Table 1. Infiltrate at 45°C, undergo aging and formation steps, and obtain a battery. Determine the electrochemical performance and safety characteristics with reference to GB / T 28164, and record the shortest infiltration time when the electrochemical performance and safety characteristics meet the requirements. The results are shown in Table 1.

[0121] Comparative Example 1

[0122] This comparative example provides a cell processing method, a modified cell, a battery, and a preparation method thereof, which are substantially the same as those in Example 1, with the main differences being that in step 200, no ventilation system is used, and an oxygen storage tank is used to provide oxygen; and in step 300, oxygen and plasma flow in a disordered manner. Steps 200 and 300 are specifically as follows:

[0123] Step 200: Place the battery cell in a reaction chamber, and electrically connect the positive electrode tab and the negative electrode tab of the battery cell to the first electrode and the second electrode disposed in the reaction chamber, respectively. The first electrode and the second electrode are connected to a radio frequency power supply outside the reaction chamber, and the oxygen tank is connected to the reaction chamber through the vent of the reaction chamber.

[0124] Step 300: Evacuate the reaction chamber, supply oxygen into the reaction chamber through an oxygen tank, set the frequency of the RF power supply to 13.56 Hz, excite the disordered oxygen flowing between the electric fields to form a plasma without flow, and maintain the discharge for 40 seconds.

[0125] Table 1

[0126] As can be seen from Table 1, under the condition that both the electrochemical performance and safety characteristics meet the requirements, compared with Comparative Example 1, Example 1 has significantly shortened the injection time and the immersion time, and the efficiency of the two processes is significantly improved.

[0127] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0128] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for processing a battery cell, characterized in that: The following steps are involved: Placing the battery cell in the reaction chamber; A plasma flowing along a preset direction is excited or introduced in the reaction chamber, wherein the preset direction includes a direction flowing through the battery core, and the battery core is processed by using the flowing plasma.

2. The method for processing a battery cell according to claim 1, characterized in that: The exciting and forming plasma flowing along a preset direction in the reaction chamber comprises the following steps: Connect the positive and negative poles of the battery cell to electricity to form an electric field; A preset gas is introduced into the reaction chamber to flow along the preset direction. When the preset gas flows through the battery core, it is excited by the electric field to form plasma that flows along the preset direction.

3. The method for processing a battery cell according to claim 2, characterized in that: The step of introducing a preset gas into the reaction chamber to form a flow along the preset direction comprises the following steps: A preset gas is input into the reaction chamber, and the preset gas is made to flow along the preset direction.

4. The method for processing a battery cell according to claim 1, characterized in that: The step of introducing plasma into the reaction chamber to form a flow in a preset direction comprises the following steps: inputting plasma into the reaction chamber; The plasma entering the reaction chamber is made to flow along a preset direction.

5. The method for processing a battery cell according to any one of claims 1 to 4, characterized in that: The battery cell includes stacked positive electrode sheets, a separator and a negative electrode sheet, and the direction of the flow through the battery cell includes the direction of flowing through the pores of the positive electrode sheet, the pores of the separator and the pores of the negative electrode sheet in sequence and / or the direction of flowing through the pores of the negative electrode sheet, the pores of the separator and the pores of the positive electrode sheet in sequence.

6. A battery cell processing device, characterized in that: The invention comprises a reaction chamber, wherein the reaction chamber is used for placing a battery core, and plasma can be excited or introduced in the reaction chamber to flow along a preset direction, wherein the preset direction includes a direction flowing through the battery core.

7. The battery cell processing equipment according to claim 6, characterized in that: Two electrodes are also provided in the reaction chamber, and the two electrodes are respectively used to be electrically connected to the positive electrode tab and the negative electrode tab of the battery cell to form an electric field to excite the preset gas flowing through the battery cell to form plasma flowing along the preset direction.

8. The battery cell processing equipment according to claim 7, characterized in that: It also includes a first ventilation system, which is connected to the reaction chamber and is used to input a preset gas into the reaction chamber and make the preset gas flow along the preset direction.

9. The battery cell processing equipment according to claim 7, characterized in that: It also includes a plasma generating device, wherein a plasma output end of the plasma generating device is connected to the reaction chamber, and the plasma generating device is used to input plasma into the reaction chamber; It also includes a second ventilation system, which is communicated with the reaction chamber and is used to make the plasma entering the reaction chamber flow along a preset direction.

10. A battery, characterized in that: The invention comprises a modified battery cell, wherein the modified battery cell is obtained by being processed by the method according to any one of claims 1 to 5.

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