Battery piece electric injection method, electric injection battery piece and electric injection equipment

Abstract

The invention relates to a battery piece electric injection method, an electric injection battery piece and electric injection equipment. The battery piece electric injection method comprises the steps that a battery piece is provided; carrying out heating treatment on the battery piece; multiple times of electric injection processing are carried out on the heated battery piece, time intervals exist between the electric injection processing, the time, the temperature and the current of each time of electric injection processing are the same, and the time of each time of electric injection processing is 400-500 s. According to the battery piece electric injection method, multiple times of electric injection are carried out on the heated battery piece, meanwhile, the time, the temperature and the current of each time of electric injection processing are controlled to be the same, temperature control over the battery piece in the electric injection process can be stable, and the battery piece electric injection efficiency is improved. And the risk that ohmic contact is damaged by secondary sintering due to over-high battery temperature caused by continuous electric injection to the battery piece is reduced. According to the battery piece electric injection method, the effects of improving the efficiency of the battery piece and reducing the LID are good.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a method for injecting electricity into a cell, an electric injection cell, and an electric injection device. Background Art

[0002] Impurities and defects in silicon crystals will have a significant impact on the performance of solar cells, making it difficult to improve the conversion efficiency of solar cells. Impurities in silicon crystals include non-metallic impurities such as oxygen, carbon, and nitrogen, as well as metal impurities such as iron, cobalt, nickel, chromium, and copper. Defects in silicon crystals include grain boundaries, dislocations, and silicon dangling bonds on the surface of the crystal. Impurities and defects in silicon crystals will reduce the lifetime of carriers, thereby attenuating the conversion efficiency of solar cells.

[0003] In the process of manufacturing solar cells, the impurities and defects on the surface of the solar cell substrate can be passivated by depositing silicon nitride film; and hydrogen atoms can be introduced near the surface of the silicon crystal through hydrogen plasma treatment to passivate the impurities and defects on the surface of the solar cell substrate. However, it is difficult to introduce high concentrations of hydrogen atoms inside the substrate by depositing silicon nitride film and hydrogen plasma treatment, so the passivation effect on impurities and defects inside the solar cell substrate is relatively weak. The electrical injection process directly uses direct current to inject carriers into the solar cell, which can make the hydrogen atoms in the silicon crystal become charged, so that it can passivate the decayed boron-oxygen complex and some impurity defects in the silicon crystal, and finally achieve the purpose of resisting light decay and improving the conversion efficiency of solar cells. However, the traditional electrical injection process has poor effect on improving the efficiency of solar cells and reducing the light-induced degradation effect (LID). Summary of the invention

[0004] Based on this, it is necessary to provide a battery cell electricity injection method, an electricity injection battery cell, and an electricity injection device. The battery cell electricity injection method has a good effect on improving battery efficiency and reducing LID.

[0005] In a first aspect, the present application provides a method for electric injection into a battery cell, comprising: providing a battery cell; heating the battery cell; performing multiple electric injection treatments on the heated battery cell in sequence, with a time interval between each two electric injection treatments, the time, temperature and current of each electric injection treatment being the same, and the time of each electric injection treatment being 400s to 500s.

[0006] In some embodiments, the temperature of each electrical injection treatment is 100° C. to 200° C.

[0007] In some embodiments, the current of each electrical injection treatment is 2A-6A.

[0008] In some embodiments, the number of electrical injection treatments is 2 to 7 times.

[0009] In some embodiments, the total time of the multiple electrical injection treatments is 800s to 3500s.

[0010] In some embodiments, the time interval between each electrical injection treatment is 1s to 10s.

[0011] In some embodiments, it is characterized in that the temperature of the heating treatment is 100°C~200°C.

[0012] In some embodiments, the temperature rise treatment time is 400s~500s.

[0013] In some embodiments, after performing multiple electrical injection treatments on the battery cell after the temperature is increased, the method further includes: cooling the battery cell after the multiple electrical injection treatments.

[0014] In some embodiments, the cooling time is 1600s~2000s.

[0015] In a second aspect, the present application provides an electrically injected battery cell, which is obtained by processing any of the above-mentioned battery cell electrically injected methods.

[0016] In a third aspect, the present application provides an electric injection device for performing electric injection processing on a battery cell using any of the above-mentioned battery cell electric injection methods, comprising:

[0017] A temperature raising device, the temperature raising device is used to perform the temperature raising process on the battery cell;

[0018] The electric injection device is used to perform multiple electric injection treatments on the battery cell after heating, and control the time interval between each two electric injection treatments, the time, temperature and current of each electric injection treatment are the same, and the time of each electric injection treatment is 400s~500s.

[0019] The above-mentioned battery cell electrical injection method includes heating the battery cell and performing multiple electrical injection treatments on the heated battery cell. There is a time interval between each electrical injection treatment, and the time, temperature and current of each electrical injection treatment are the same. The battery cell is first heated to provide the energy required to open the HH bond on the back of the battery cell. The heating provides energy to increase the diffusion rate of hydrogen atoms. The battery cell after heating is subjected to multiple electrical injections for a time period of 400s to 500s, which can make the temperature control of the battery cell more stable during the electrical injection process, and reduce the risk of secondary sintering and destruction of ohmic contact caused by excessive battery temperature due to continuous electrical injection of the battery cell. At the same time, the time, temperature and current of each electrical injection treatment are controlled to be the same, which can improve the temperature stability of the battery cell when the battery cell is electrically injected multiple times, and the effect of electrical injection is better. The battery cell electrical injection method of the present application has a good effect on improving the efficiency of the battery cell and reducing LID. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a process of a battery cell electricity injection method provided in an embodiment of the present application;

[0021] Figure 2 A schematic diagram of the temperature of the battery cell provided in Example 1 of the present application when it is located at each station in the heating zone and the electro-injection zone;

[0022] Figure 3 A schematic diagram of the temperature of the battery cell provided in Example 2 of the present application when it is located at each station in the heating zone and the electro-injection zone;

[0023] Figure 4 A schematic diagram of the temperature of the battery cell provided in Example 3 of the present application when it is located at each station in the heating zone and the electro-injection zone;

[0024] Figure 5 A schematic diagram of the temperature of the battery cells provided in Example 4 of the present application when they are located at the heating zone station and the electro-injection zone stations. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0027] Reference Figure 1 , an embodiment of the present application provides a battery cell electrical injection method, comprising:

[0028] S10: Provide battery cells;

[0029] S20: heating the battery cell;

[0030] S30: performing multiple electrical injection treatments on the heated battery cells in sequence, with a time interval between each two electrical injection treatments, the time, temperature and current of each electrical injection treatment being the same, and the time of each electrical injection treatment being 400s to 500s.

[0031] It is understood that the electrical injection process refers to applying direct current to the battery cell.

[0032] The above-mentioned battery cell electric injection method includes heating the battery cell and performing multiple electric injection treatments on the heated battery cell. There is a time interval between each electric injection treatment, and the time, temperature and current of each electric injection treatment are the same. The battery cell is first heated to provide the energy required to open the HH bond on the back of the battery cell, and the heating provides energy to increase the diffusion rate of hydrogen atoms. The battery cell after heating is subjected to multiple electric injections for a time of 400s to 500s, which can make the temperature control of the battery cell more stable during the electric injection process, and reduce the risk of secondary sintering and destroying the ohmic contact caused by excessive battery temperature due to continuous electric injection of the battery cell. At the same time, the time, temperature and current of each electric injection treatment are controlled to be the same, which can improve the temperature stability of the battery cell when the battery cell is electrically injected multiple times, and the effect of electric injection is better. Electric injection applies direct current to the battery cell while controlling the temperature of the battery cell, which can reduce the binding barrier of other impurity atoms in crystalline silicon to hydrogen atoms, and can convert more hydrogen into electrically neutral hydrogen atoms. Hydrogen atoms are more likely to diffuse in silicon crystals than hydrogen ions, so that the speed and efficiency of hydrogen atoms passivating defects in silicon crystals are faster. The battery cell electricity injection method of the present application has a good effect on improving the efficiency of the battery cell and reducing the LID.

[0033] Within the time range of each electrical injection, the efficiency of passivation of defects in silicon crystals during electrical injection is high, the effect is good, and the efficiency of the cell and the reduction of LID are good. When the time of each electrical injection treatment is too short, the effect of hydrogen atoms on the passivation of defects in silicon crystals is poor; when the time of each electrical injection treatment is too long, secondary sintering is likely to damage the ohmic contact. Optionally, the time of each electrical injection treatment is 400s, 405s, 410s, 415s, 420s, 425s, 430s, 435s, 440s, 445s, 450s, 455s, 460s, 465s, 470s, 475s, 480s, 485s, 490s, 495s or 500s.

[0034] In some embodiments, the temperature of each electrical injection treatment is 100°C to 200°C. Within the temperature range of the electrical injection treatment, the efficiency of passivation of defects in silicon crystals during electrical injection is high, the effect is good, and the efficiency of the battery cell and the reduction of LID are good. When the temperature of each electrical injection treatment is too low, the speed of hydrogen atoms passivating defects in silicon crystals is slow and the efficiency is low; when the temperature of each electrical injection treatment is too high, it is easy to cause secondary sintering to destroy the ohmic contact. Optionally, the temperature of each electrical injection treatment is 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C or 200°C.

[0035] In some embodiments, the current of each electrical injection treatment is 2A to 6A. Within the current range of each electrical injection treatment, the speed and efficiency of hydrogen atoms passivating defects in silicon crystals are high, and the efficiency of the cell is improved and the LID is reduced. When the current of each electrical injection treatment is too low, the speed of hydrogen atoms passivating defects in silicon crystals is slow and the efficiency is low; when the current of each electrical injection treatment is too high, it is easy to cause the temperature of the cell to be too high, which is easy to cause secondary sintering to damage the ohmic contact. Optionally, the current of each electrical injection treatment is 2A, 2.1A, 2.2A, 2.3A, 2.4A, 2.5A, 2.6A, 2.7A, 2.8A, 2.9A, 3.0A, 3.1A, 3.2A, 3.3A, 3.4A, 3.5A, 3.6A, 3.7A, 3.8A, 3.9A, 4A, 4.1A, 4.2A, 4.3A, 4.4A, 4.5A, 4.6A, 4.7A, 4.8A, 4.9A, 5A, 5.1A, 5.2A, 5.3A, 5.4A, 5.5A, 5.6A, 5.7A, 5.8A, 5.9A or 6A.

[0036] In some embodiments, the number of times of the electrical injection treatment is 2 to 7 times. Within the range of the number of times of the electrical injection treatment, the hydrogen atoms have a better passivation effect on the defects in the silicon crystal, and have a better effect on improving the efficiency of the cell and reducing the LID. Optionally, the number of times of the electrical injection treatment is 2, 3, 4, 5, 6 or 7 times.

[0037] In some embodiments, the total time of the multiple electrical injection treatments is 800s to 3500s. Within the total time range of the multiple electrical injection treatments, the passivation effect on defects in the silicon crystal is better, and the efficiency improvement of the battery cell and the reduction effect of LID are better. Optionally, the total time of the multiple electrical injection treatments is 800s, 900s, 1000s, 1100s, 1200s, 1300s, 1400s, 1500s, 1600s, 1700s, 1800s, 1900s, 2000s, 2100s, 2200s, 2300s, 2400s, 2500s, 2600s, 2700s, 2800s, 2900s, 3000s, 3100s, 3200s, 3300s, 3400s or 3500s.

[0038] In some embodiments, the time interval between each electrical injection treatment is 1s to 10s. When the time interval between each electrical injection treatment is too short, the electrical injection may cause the temperature of the cell to be too high, which may easily cause secondary sintering to damage the ohmic contact; when the time interval between each electrical injection treatment is too long, the temperature of the cell will drop significantly during the time interval between two electrical injection treatments, affecting the temperature control of the cell during the electrical injection treatment, resulting in a slower passivation speed and lower efficiency of hydrogen atoms on defects in the silicon crystal, and a poor electrical injection effect. Optionally, the time interval between each electrical injection treatment is 1s, 1.2s, 1.4s, 1.6s, 1.8s, 2.0s, 2.2s, 2.4s, 2.6s, 2.8s, 3.0s, 3.2s, 3.4s, 3.6s, 3.8s, 4.0s, 4.2s, 4.4s, 4.6s, 4.8s, 5.0s, 5.2s, 5.4s, 5.6s, 5.8s, 6.0s, 6.2s, 6.4s, 6.6s, 6.8s, 7.0s, 7.2s, 7.4s, 7.6s, 7.8s, 8.0s, 8.2s, 8.4s, 8.6s, 8.8s, 9.0s, 9.2s, 9.4s, 9.6s, 9.8s or 10s.

[0039] In some embodiments, it is characterized in that the temperature of the heating treatment is 100°C to 200°C. The heating treatment can provide the energy required to open the HH bond on the back of the battery cell, and the heating provides energy to increase the diffusion rate of hydrogen atoms. Within the temperature range of the heating treatment, the effect of electrical injection is better, and the efficiency improvement of the battery cell and the reduction of LID are better. When the temperature of the heating treatment is too low, the passivation effect of hydrogen atoms on defects in the silicon crystal is poor; when the temperature of the heating treatment is too high, it is easy to cause secondary sintering to destroy the ohmic contact. Optionally, the temperature of the heating treatment is 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C or 200°C.

[0040] In some embodiments, the time of the temperature increase treatment is 400s to 500s. Within the time range of the temperature increase treatment, the effect of the electric injection is better, and the efficiency of the battery cell and the effect of reducing the LID are better. Optionally, the time of the temperature increase treatment is 400s, 405s, 410s, 415s, 420s, 425s, 430s, 435s, 440s, 445s, 450s, 455s, 460s, 465s, 470s, 475s, 480s, 485s, 490s, 495s or 500s.

[0041] In some embodiments, the temperature of each electrical injection process is the same as the temperature of the temperature increase process.

[0042] In some embodiments, the duration of each electrical injection process is the same as the duration of each temperature increase process.

[0043] In some embodiments, the temperature and time of each electrical injection treatment and the temperature increase treatment are the same. When the temperature and time of each electrical injection treatment and the temperature increase treatment are the same, it is convenient to process the battery cells in an assembly line, and the processed battery cells can be transferred to the next station for subsequent processing at the same time point.

[0044] In some embodiments, after performing multiple electrical injection treatments on the heated cell, the method further includes: cooling the cell after the multiple electrical injection treatments. Since the cell temperature after the electrical injection is relatively high, long-term and sufficient cooling can reduce the reactivation rate of the passivated defects.

[0045] In some embodiments, the cooling time is 1600s to 2000s. Optionally, the cooling time is 1600s, 1620s, 1640s, 1660s, 1680s, 1700s, 1720s, 1740s, 1760s, 1780s, 1800s, 1820s, 1840s, 1860s, 1880s, 1900s, 1920s, 1940s, 1960s, 1980s or 2000s.

[0046] In some embodiments, the battery cell electrical injection method includes the following steps:

[0047] (1) Provide battery cells;

[0048] (2) The battery cell is subjected to a heating treatment for 400s to 500s at a temperature of 100°C to 200°C;

[0049] (3) The heated battery cell is subjected to 2 to 7 electrical injection treatments, with a time interval between each electrical injection treatment of 1s to 10s; the time, temperature and current of each electrical injection treatment are the same; the total time of multiple electrical injection treatments is 800s to 3500s, the time of each electrical injection treatment is 400s to 500s, the temperature of each electrical injection treatment is 100℃ to 200℃, and the current of each electrical injection treatment is 2A to 6A;

[0050] (4) Cooling the battery cells after multiple electrical injection treatments for a period of 1600s to 2000s.

[0051] In some embodiments, the battery cell electrical injection method comprises the following steps:

[0052] (1) Provide battery cells;

[0053] (2) The battery cell is subjected to a heating treatment for 400s to 500s at a temperature of 100°C to 200°C;

[0054] (3) The heated battery cell is subjected to 2 to 7 electrical injection treatments, with a time interval between each electrical injection treatment of 1s to 10s; the time, temperature and current of each electrical injection treatment are the same; the total time of multiple electrical injection treatments is 800s to 3500s, the time of each electrical injection treatment is 400s to 500s, the temperature of each electrical injection treatment is 100℃ to 200℃, and the current of each electrical injection treatment is 2A to 6A;

[0055] (4) Cooling the battery cells after multiple electrical injection treatments for a period of 1600s to 2000s.

[0056] Yet another embodiment of the present application provides an electrically injected battery cell, which is obtained by processing any of the above-mentioned battery cell electrically injected methods.

[0057] The present application further provides an electric injection device, which is used to perform electric injection processing on a battery cell using any of the above-mentioned battery cell electric injection methods, comprising:

[0058] A heating device, which is used to heat the battery cell;

[0059] The electric injection device is used to perform multiple electric injection treatments on the heated battery cells and control the time interval between each two electric injection treatments. The time, temperature and current of each electric injection treatment are the same, and the time of each electric injection treatment is 400s~500s.

[0060] In some embodiments, the electric injection device includes a heating station, an electric injection station and a cooling station, the heating station includes a temperature increasing device, and the electric injection station includes an electric injection device. The upper and lower electrodes of the heating station only have a heating function and do not have an electrification effect. The upper and lower electrodes of the electric injection station have heating and electrification functions.

[0061] In some embodiments, the number of the electrical injection processes is plural, and the number of the cooling stations is plural.

[0062] In one embodiment, the number of heating stations is one, the number of electric injection stations is seven, and the number of cooling stations is four. One of the cooling stations is an exhaust cooling station, and three are fan and exhaust combined cooling stations. When the electric injection equipment is used to perform electric injection treatment on the battery cell, when the working time of each station is the same, that is, the time of the heating treatment, the time of each electric injection treatment, and the cooling time of each cooling station are the same, the battery cell can be processed in each station in sequence, which is convenient for automated operation and has a high efficiency of electric injection treatment.

[0063] In one embodiment, the above-mentioned electric injection equipment is used to perform a temperature increase process, seven electric injection processes, and four cooling processes on each battery cell.

[0064] The following are specific embodiments

[0065] In the following embodiments, an electric injection device is used to perform electric injection treatment on the battery cells. In the electric injection device, the number of heating stations is one, the number of electric injection stations is seven, and the number of cooling stations is four. The upper and lower electrodes of the heating station only have a heating function and do not have an electrification effect. The upper and lower electrodes of the electric injection station have heating and electrification functions. One of the cooling stations is an exhaust cooling station, and the other three are fan, exhaust combined cooling stations. They are numbered in sequence as stations 1 to 12. In each embodiment, multiple battery cells are processed in each station in turn, that is, a temperature treatment is performed in station 1, and then 7 electric injection treatments are performed in stations 2 to 8, and then cooling treatments are performed in stations 9 to 12. After the battery cells complete the corresponding treatment in each station, they enter the next station in sequence for the next step of processing, and new battery cells are added in station 1. The processing time of each different station is the same, and all stations are processed synchronously.

[0066] Example 1

[0067] The battery cell electricity injection method is as follows:

[0068] The battery cell was subjected to a heating treatment, the heating treatment time was 400s, and the heating treatment temperature was 100°C. The heated battery cell was subjected to 7 electrical injection treatments, the time interval between each electrical injection treatment was 5s, the total time of multiple electrical injection treatments was 2800s, the time of each electrical injection treatment was 400s, the temperature of each electrical injection treatment was 100°C, and the current of each electrical injection treatment was 2A. The battery cell after multiple electrical injection treatments was cooled, the cooling time in each station was 400s, and the total cooling time was 1600s. The setting parameters of each station in the battery cell electrical injection method in Example 1 are shown in Table 1 below:

[0069] Table 1

[0070]

[0071] Reference Figure 2 , Figure 2 The temperature diagram of the battery cell provided in Example 1 when it is located in the heating zone station and each station of the electric injection zone. When the battery cell in Example 1 is located in each station of stations 1 to 8, the actual temperature of the surface of the battery cell is as shown in Table 2 below:

[0072] Table 2

[0073]

[0074] Example 2

[0075] The battery cell electricity injection method is as follows:

[0076] The battery cell is subjected to a heating treatment, the heating treatment time is 450s, and the heating treatment temperature is 150°C. The heated battery cell is subjected to 7 electrical injection treatments, the time interval between each electrical injection treatment is 5s, the total time of multiple electrical injection treatments is 3150s, the time of each electrical injection treatment is 450s, the temperature of each electrical injection treatment is 150°C, and the current of each electrical injection treatment is 4A. The battery cell after multiple electrical injection treatments is cooled, the cooling time in each station is 450s, and the total cooling time is 1800s. The setting parameters of each station in the battery cell electrical injection method in Example 1 are shown in Table 3 below:

[0077] Table 3

[0078]

[0079] Reference Figure 3 , Figure 3 The temperature diagram of the battery cell provided in Example 2 when it is located in the heating zone station and each station of the electric injection zone. When the battery cell in Example 2 is located in each station of stations 1 to 8, the actual temperature of the surface of the battery cell is as shown in Table 4 below:

[0080] Table 4

[0081]

[0082] Example 3

[0083] The battery cell electricity injection method is as follows:

[0084] The battery cell was subjected to a heating treatment, the heating treatment time was 500s, and the heating treatment temperature was 200°C. The heated battery cell was subjected to 7 electrical injection treatments, the time interval between each electrical injection treatment was 5s, the total time of multiple electrical injection treatments was 3500s, the time of each electrical injection treatment was 500s, the temperature of each electrical injection treatment was 200°C, and the current of each electrical injection treatment was 6A. The battery cell after multiple electrical injection treatments was cooled, the cooling time in each station was 500s, and the total cooling time was 2000s. The setting parameters of each station in the battery cell electrical injection method in Example 1 are shown in Table 5 below:

[0085] Table 5

[0086]

[0087] Reference Figure 4 , Figure 4 The temperature diagram of the battery cell provided in Example 3 when it is located in the heating zone station and each station of the electric injection zone. When the battery cell in Example 3 is located in each station of stations 1 to 8, the actual temperature of the surface of the battery cell is as shown in Table 6 below:

[0088] Table 6

[0089]

[0090] Example 4

[0091] The battery cell electricity injection method is as follows:

[0092] The battery cell was subjected to a heating treatment, the heating treatment time was 400s, and the heating treatment temperature was 100°C. The heated battery cell was subjected to 7 electrical injection treatments, the time interval between each electrical injection treatment was 5s, the total time of multiple electrical injection treatments was 2800s, the time of each electrical injection treatment was 400s, the temperature of each electrical injection treatment was 100°C, and the current of each electrical injection treatment was 1A. The battery cell after multiple electrical injection treatments was cooled, the cooling time in each station was 400s, and the total cooling time was 1600s. The setting parameters of each station in the battery cell electrical injection method in Example 1 are shown in Table 7 below:

[0093] Table 7

[0094]

[0095] Reference Figure 5 , Figure 5 The temperature diagram of the battery cell provided in Example 4 when it is located in the heating zone station and each station of the electric injection zone. When the battery cell in Example 4 is located in each station of stations 1 to 8, the actual temperature of the surface of the battery cell is as shown in Table 8 below:

[0096] Table 8

[0097]

[0098] Photoelectric performance tests were performed on multiple cell samples before and after the electrical injection treatment in Examples 1 to 4. The test results are shown in Table 9 below, including oc ,I sc , FF, E ta , ΔE ta , LID and ΔLID. Among them, U oc ,I sc , FF, E ta and LID are averaged over all samples, ΔE ta and ΔLID are E before and after electrical injection ta and the difference between LID.

[0099] Table 9

[0100]

[0101] From the test results in Examples 1 to 4, it can be seen that the efficiency of the cells in each example is improved before and after electrical injection, and the LID is reduced. Among them, the reduction in LID of the samples in Examples 1 to 3 is more obvious, reaching 0.55%, while the reduction in LID and the increase in efficiency in Example 4 are not obvious. This is because the current of each electrical injection treatment in Example 4 is small, 1A, which leads to a lower temperature of the cell during actual operation and a relatively poor effect of electrical injection.

[0102] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0103] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims, and the description and drawings may be used to interpret the contents of the claims.

Claims

1. A method for injecting electricity into a battery cell, characterized in that: include: Provide battery cells; Performing a temperature raising process on the battery cell; The battery cells after heating are subjected to multiple electrical injection treatments in sequence, with a time interval between each two electrical injection treatments, the time, temperature and current of each electrical injection treatment being the same, and the time of each electrical injection treatment being 400s to 500s.

2. The battery cell electrical injection method according to claim 1, characterized in that: The temperature of each electrical injection treatment is 100°C to 200°C; And / or, the current of each electrical injection treatment is 2A~6A.

3. The battery cell electrical injection method according to claim 1, characterized in that: The number of electrical injection treatments is 2 to 7 times.

4. The battery cell electrical injection method according to claim 3, characterized in that: The total time of the multiple electrical injection treatments is 800s to 3500s.

5. The battery cell electrical injection method according to claim 1, characterized in that: The time interval between each electrical injection treatment is 1s to 10s.

6. The battery cell electric injection method according to any one of claims 1 to 5, characterized in that: The temperature of the heating treatment is 100°C to 200°C; And / or, the temperature rising treatment time is 400s~500s.

7. The battery cell electrical injection method according to any one of claims 1 to 5, characterized in that: After the battery cell after the temperature is raised is subjected to multiple electrical injection processes, the method further comprises: The battery cell is cooled after multiple electrical injection processes.

8. The battery cell electrical injection method according to claim 7, characterized in that: The cooling time is 1600s~2000s.

9. An electric injection cell, characterized in that: The method is obtained by processing the battery cell electric injection method according to any one of claims 1 to 8.

10. An electrical injection device, characterized in that: The method for electrically injecting a battery cell using the battery cell electrical injection method according to any one of claims 1 to 8 comprises: A temperature raising device, the temperature raising device is used to perform the temperature raising process on the battery cell; The electric injection device is used to perform multiple electric injection treatments on the battery cell after heating, and control the time interval between each two electric injection treatments, the time, temperature and current of each electric injection treatment are the same, and the time of each electric injection treatment is 400s~500s.

Images