Formation device and formation method for battery cell

Abstract

The application discloses a formation device and a formation method for an electric core. The formation device comprises a container body and a cover body. At least three blocking devices are arranged in the container body, and the container body is divided into at least three liquid storage tanks by the at least three blocking devices. Different electrolytes are carried in each liquid storage tank. The cover body is provided with at least three connecting pieces near one side of the container body. The connecting pieces correspond to the blocking devices, are connected with the blocking devices, and drive the blocking devices to reciprocate along a first direction. The container body is extended with a sharp nozzle at a lower end for sealingly cooperating with a liquid injection hole of the electric core. The application can not only store several different types of electrolytes at the same time to realize integrated liquid injection, but also release different types of electrolytes into the electric core to adjust the internal temperature of the electric core while supplementing the liquid, thereby ensuring the temperature stability of formation under a large current, avoiding the internal temperature of the electric core from rising too fast, and further improving the formation effect and performance of the electric core.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and more specifically, to a formation apparatus and a formation method for battery cells. Background Technology

[0002] Lithium-ion batteries have become widely used energy storage devices in recent years due to their high specific energy, high power density, high efficiency, and environmental friendliness. They are widely used in consumer electronics, electric drives, and energy storage power stations. The formation process is a crucial step in lithium-ion battery development, primarily used to activate the battery and form a solid electrolyte interphase (SEI) film on the negative electrode surface. Rapid, uniform, and dense formation of the SEI film not only improves formation efficiency but also enhances the initial efficiency, rate capability, and cycle performance of lithium-ion batteries.

[0003] The core of the formation process control lies in negative pressure degassing during gas generation and adjusting the temperature rise. Currently, the formation cup can only hold one type of electrolyte, which limits the range of electrolytes that can be selected for the battery cell during formation. In addition, during the charging and discharging temperature rise in the formation process, the cooling can only be achieved by relying on the ambient temperature, resulting in poor temperature stability inside the battery cell. Therefore, this is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] In view of this, the present invention provides a formation apparatus and a formation method for battery cells to solve the problems of the formation apparatus carrying a single electrolyte and poor temperature stability of the battery cells.

[0005] In a first aspect, this application provides a formation apparatus, including a container body and a cover connected to the container body. The container body is provided with at least three blocking devices, which divide the container body into at least three liquid storage tanks, each of which contains a different electrolyte.

[0006] The cover is provided with at least three connectors on the side near the container body. The connectors correspond to the blocking device, are connected to the blocking device, and drive the blocking device to reciprocate along a first direction, which is from the cover to the container body.

[0007] The lower end of the container body extends a pointed nozzle for sealing with the battery cell's liquid injection hole.

[0008] Secondly, this application provides a method for forming a battery cell, wherein an electrolyte is injected into the battery cell using a forming apparatus, the forming apparatus including any of the forming apparatuses described above;

[0009] Insert the pointed tip of the container body into the electrolyte injection hole of the battery cell, inject different electrolytes into different storage tanks, and then cover the container body with the cap.

[0010] Electrolyte is released in the corresponding region according to the cell temperature rise curve to complete cell activation.

[0011] Optionally, the step of releasing electrolyte in the corresponding region according to the cell temperature rise curve includes:

[0012] The electrolyte includes a first electrolyte, a lithium-replenishing electrolyte, and a second electrolyte. The first electrolyte is injected into a first storage tank, the lithium-replenishing electrolyte is injected into a second storage tank, and the second electrolyte is injected into a third storage tank.

[0013] Based on the cell temperature rise status, the electrolyte is released according to the first charging current range;

[0014] Based on the cell temperature rise status, the lithium replenishing electrolyte is released according to the second charging current range;

[0015] Based on the cell temperature rise status, the two electrolyte injections are released according to the discharge current range.

[0016] Optionally, the step of releasing electrolyte in the corresponding region according to the cell temperature rise curve includes:

[0017] The electrolyte includes a first electrolyte, a lithium replenishing electrolyte, and a second electrolyte. The first electrolyte is injected into a first storage tank, the second electrolyte is injected into a second storage tank, and the lithium replenishing electrolyte is injected into a third storage tank.

[0018] Based on the cell temperature rise status, the first injection of electrolyte is released based on a first potential range, the first injection of electrolyte and the second injection of electrolyte are released sequentially based on a second potential range, and the lithium replenishing electrolyte is released based on a third potential range, wherein the first potential range is smaller than the second potential range, and the second potential range is smaller than the third potential range.

[0019] Compared with the prior art, the formation apparatus provided by the present invention achieves at least the following beneficial effects:

[0020] The present invention provides a formation apparatus and a formation method for battery cells. The formation apparatus includes a container body and a cover connected to the container body. At least three blocking devices are disposed within the container body, dividing the container body into at least three liquid storage tanks, each containing a different electrolyte. At least three connectors are disposed on the side of the cover near the container body, corresponding to and connected to the blocking devices, and driving the blocking devices to reciprocate along a first direction, which is from the cover towards the container body. A nozzle extends from the lower end of the container body for sealing with the battery cell's electrolyte injection hole. This design not only allows for the simultaneous storage of several different types of electrolytes, thus achieving integrated electrolyte injection, but also enables the release of different types of electrolyte into the battery cell. This allows for electrolyte replenishment while simultaneously adjusting the internal temperature of the battery cell, ensuring temperature stability during formation under high current, thereby preventing excessively rapid internal temperature rise and improving the formation effect and performance of the battery cell.

[0021] Of course, any product implementing this invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0022] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0024] Figure 1 This is a schematic diagram of the open state of the container body and the cover in a formation apparatus provided by the present invention;

[0025] Figure 2 This is a schematic diagram of the closed state of the container body and the cover in a formation apparatus provided by the present invention;

[0026] Figure 3 This is a schematic diagram of the structure of the base plate provided by the present invention;

[0027] Figure 4 yes Figure 2 Enlarged view of a portion of point A in the middle;

[0028] Figure 5 This is a schematic diagram of the structure of the first partition, the second partition, and the third partition provided by the present invention;

[0029] Figure 6 This is a schematic diagram of the open state of the container body and the cover in another formation device provided by the present invention;

[0030] Figure 7This is a schematic diagram of the structure of the first blocking plate, the second blocking plate, and the third blocking plate provided by the present invention;

[0031] Figure 8 This is a schematic diagram of the open state of the container body and the cover in another formation apparatus provided by the present invention;

[0032] Figure 9 This is a schematic diagram of the open state of the container body and the cover in another formation apparatus provided by the present invention;

[0033] Figure 10 This is one of the schematic flowcharts of the formation method for battery cells provided by the present invention;

[0034] Figure 11 This is the cell temperature rise curve provided by the present invention;

[0035] Figure 12 This is the second schematic diagram of the formation method for battery cells provided by the present invention;

[0036] Figure 13 This is the third schematic diagram of the formation method for battery cells provided by the present invention. Detailed Implementation

[0037] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0038] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0039] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0040] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0041] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0042] Figure 1 This is a schematic diagram of the open state of the container body and the cover in a formation apparatus provided by the present invention; Figure 2 This is a schematic diagram showing the closed state of the container body and the lid in a formation apparatus provided by the present invention; combined with Figure 1 and Figure 2 As shown, this embodiment provides a formation apparatus, including a container body 1 and a cover 2 connected to the container body 1. The container body 1 is provided with at least three blocking devices 11, which divide the container body 1 into at least three liquid storage tanks 3, each liquid storage tank 3 containing a different electrolyte. The cover 2 is provided with at least three connectors 21 on the side near the container body 1. The connectors 21 correspond to the blocking devices 11 and are connected to the blocking devices 11, and drive the blocking devices 11 to reciprocate along a first direction X, where the first direction X is from the cover 2 to the side of the container body 1. The lower end of the container body 1 extends a pointed nozzle 4 for sealing with the liquid injection hole of the battery cell 6.

[0043] Specifically, in combination Figure 1 and Figure 2 As shown, this formation device is suitable for the formation of battery cell 6. During the production process of battery cell 6, the initially formed battery cell 6 needs to have an appropriate current passed through its electrodes to activate the active materials inside the battery cell 6. This process is called formation. Formation generates a passivation interface film (SEI film) on the electrode surface, which can prevent the electrolyte from reacting with the electrode active materials. Therefore, formation is a very critical step in the production process of battery cell 6. The quality of the formation process directly affects the performance of battery cell 6. Battery cell 6 can only exhibit its true performance after formation. If battery cell 6 does not undergo formation, it cannot perform normal charging and discharging.

[0044] The formation device includes a container body 1 and a cover 2. The cover 2 can cover the container body 1. A plurality of blocking devices 11 are provided inside the container body 1. The two adjacent blocking devices 11 can have the same interval, or the two adjacent blocking devices 11 can have different intervals. Of course, the interval between the two adjacent blocking devices 11 can also be adjusted according to actual needs. This embodiment does not impose specific limitations.

[0045] Multiple blocking devices 11 divide the container body 1 into multiple liquid storage tanks 3, each liquid storage tank 3 containing different electrolytes (not shown in the figure). The blocking devices 11 are used to separate the electrolytes in different liquid storage tanks 3. For example, three blocking devices 11 divide the container body 1 into three liquid storage tanks 3 and a tank body. Different types of electrolytes in the three liquid storage tanks 3 can be released into the tank body (not shown in the figure) in sequence. Different electrolytes are stored in the three liquid storage tanks 3 respectively, so that the electrolyte can be selectively applied during the formation of the battery cell. Electrolyte is injected into the battery cell 6 through the tank body.

[0046] Multiple connectors 21 are provided on the side of the cover 2 near the container body 1. Each connector 21 corresponds to a blocking device 11. The connector 21 is connected to the blocking device 11 and drives the blocking device 11 to reciprocate along the first direction X, which is from the cover 2 to the container body 1. The height of each connector 21 along the first direction X can be the same. When the cover 2 is connected to the formation cabinet lifting mechanism and is raised or lowered by the formation cabinet lifting mechanism (not shown in the figure), the formation cabinet lifting mechanism can connect the cover 2 to the side away from the container body 1. It can be understood that the cover 2 raises and lowers the blocking device 11 in the vertical direction through the connectors 21 to realize the release of different electrolytes.

[0047] The lower end of the container body 1 has a pointed nozzle 4 for sealing with the liquid injection hole of the battery cell 6. The pointed nozzle 4 can be directly inserted into the liquid injection hole of the battery cell 6.

[0048] In practical use, step 1 involves injecting different electrolytes into different storage tanks 3 in the order of injecting electrolyte into the battery cell 6, moving from near the nozzle 4 to away from the nozzle 4, and then covering the container body 1 with the cover 2. Step 2 involves connecting the container body 1 with the cover 2 closed to the battery cell 6, such as inserting the nozzle 4 into the injection hole (not shown in the figure) of the battery cell 6. Step 3 involves sending the battery cell to the formation cabinet for formation. When the cover 2 is connected to the lifting mechanism of the formation cabinet, the cover 2 is raised by the lifting mechanism at the corresponding moment (such as 1-2℃ before the battery cell temperature reaches the critical point of 55℃). The cover 2 then drives the blocking device 11 to reciprocate along the first direction X, thereby releasing the electrolyte in the different storage tanks 3 and finally activating the battery cell 6. Of course, the order between steps 1 and 2 can be adjusted according to the actual situation, such as executing step 2 first and then step 1. However, the order between steps 1 and 3, as well as between steps 2 and 3, is irreversible.

[0049] Compared with the prior art, the formation apparatus provided in this embodiment achieves at least the following beneficial effects:

[0050] The formation apparatus provided in this embodiment includes a container body 1 and a cover 2 connected to the container body 1. The container body 1 is provided with at least three blocking devices 11, which divide the container body 1 into at least three liquid storage tanks 3, each of which contains a different electrolyte. The cover 2 is provided with at least three connectors 21 on the side near the container body 1. The connectors 21 correspond to the blocking devices 11 and are connected to the blocking devices 11, and drive the blocking devices 11 to reciprocate along a first direction X, where the first direction X is from the cover 2 to the side of the container body 1. The lower end of the container body 1 extends a pointed nozzle 4 for sealing with the liquid injection hole of the battery cell 6. With the above solution, not only can several different types of electrolytes be stored at the same time to achieve integrated liquid injection, but different types of electrolytes can also be released into the battery cell 6. This allows for liquid replenishment of the battery cell 6 while adjusting the internal temperature of the battery cell 6, ensuring the temperature stability of the formation under high current, thereby avoiding excessively rapid internal temperature rise of the battery cell 6, and thus improving the formation effect and performance of the battery cell 6.

[0051] In one alternative embodiment, Figure 3 This is a schematic diagram of the structure of the base plate provided by the present invention; see also Figure 3 As shown, in this embodiment, the container body 1 also includes a bottom plate 12. The bottom plate 12 is inclined towards the cover 2 along the side near the tip 4. It can be understood that the bottom plate 12 is an inclined plate. When the cover 2 drives the blocking device 11 to lift along the first direction X, the liquid storage tank 3 near the tip 4 is released. Since the bottom plate 12 is an inclined plate, the electrolyte in the liquid storage tank 3 can be released quickly and injected into the liquid injection hole of the battery cell 6 through the tip 4.

[0052] See also Figure 1 As shown, a first magnetic element 22 is provided on the side of the connector 21 near the blocking device 11. The first magnetic element 22 is located at the bottom of the connector 21. Specifically, the connector 21 can be a connecting plate, and the shape of the connecting plate can be rectangular. Each connector 21 can be provided with a first magnetic element 22 on the side near the blocking device 11 to facilitate subsequent connection with the blocking device 11. The design of each first magnetic element 22 at the bottom of the connector 21 is in preparation for the subsequent sequential opening of the blocking device 11 from the side near the tip 4 to the side away from the tip 4.

[0053] Optionally, Figure 4 yes Figure 2 Enlarged view of a section at point A; combined with Figure 2 and Figure 4As shown, the container body 1 also includes a first sidewall 13, a portion of which is connected to the side of the bottom plate 12 away from the nozzle 4. The lid 2 also includes a second sidewall 23 that abuts against the first sidewall 13. The cross-sectional shape of both the first sidewall 13 and the second sidewall 23 along the first direction X is annular. When the lid 2 is closed on the container body 1, the second sidewall 23 in the lid 2 abuts against the first sidewall 13 in the container body 1. The inclined surfaces of the first sidewall 13 near the second sidewall 23 and the second sidewall 23 near the first sidewall 13 can cooperate with each other, so as to facilitate quick insertion between the second sidewall 23 of the lid 2 and the first sidewall 13 of the container body 1.

[0054] In one alternative embodiment, Figure 5 This is a schematic diagram of the structure of the first partition, the second partition, and the third partition provided by the present invention; combined with Figure 1 and Figure 5 As shown, in this embodiment, at least three blocking devices 11 include a first partition 110, a second partition 111, and a third partition 112. The first partition 110 is located on the side closer to the tip 4, the third partition 112 is located on the side away from the tip 4, and the second partition 111 is located between the first partition 110 and the second partition 111. The first partition 110, the second partition 111, and the third partition 112 reciprocate along the first direction X. The first partition 110, the second partition 111, and the third partition 112 are provided with second magnetic elements 113 that attract the first magnetic element 22. The second magnetic element 113 in the first partition 110 is located in the middle of the first partition 110, the second magnetic element 113 in the second partition 111 is located in the upper middle part of the second partition 111, and the second magnetic element 113 in the third partition 112 is located at the top of the third partition 112.

[0055] Specifically, continue to refer to Figure 1 and Figure 5 As shown, at least three blocking devices 11 include a first partition 110, a second partition 111, and a third partition 112. The first partition 110, the second partition 111, and the third partition 112 can be rectangular in shape. The first partition 110 is located on the side closer to the nozzle 4, the third partition 112 is located on the side farther from the nozzle 4, and the second partition 111 is located between the first partition 110 and the second partition 111. The first partition 110, the second partition 111, and the third partition 112 divide the container body 1 into a tank and three liquid storage tanks 3. The tank corresponds to the nozzle 4, and the three liquid storage tanks 3 are located on one side of the tank and are arranged sequentially.

[0056] Second magnetic elements 113 are provided on the first partition 110, the second partition 111, and the third partition 112. The second magnetic elements 113 are attracted to the first magnetic elements 22. Specifically, the second magnetic elements 113 in the first partition 110 are designed in the middle of the first partition 110, the second magnetic elements 113 in the second partition 111 are designed in the upper middle part of the second partition 111, and the second magnetic elements 113 in the third partition 112 are designed at the top of the third partition 112. This can be understood as: located on the first partition 110, the second partition 111, and the third partition 22. The second magnetic element 113 on 112 is designed from low to high. With this scheme, since the first magnetic element 22 is designed at the bottom of the connector 21 in the cover 2, and the second magnetic element 113 on the first partition 110, the second partition 111 and the third partition 112 are arranged from low to high, the connector 21 of the cover 2 can sequentially drive the first partition 110, the second partition 111 and the third partition 112 to lift up, and can sequentially release the electrolyte in the storage tank 3 near the tip 4 to the electrolyte in the storage tank 3 away from the tip 4. Specifically, the first partition 110 is first lifted to release the electrolyte in the storage tank 3 between the first partition 110 and the second partition 111; then the second partition 111 is lifted to release the electrolyte in the storage tank 3 between the second partition 111 and the third partition 112; finally, the third partition 112 is lifted to release the electrolyte in the last storage tank 3. This allows the electrolyte to be released under different conditions, providing sufficient electrolyte for subsequent formation, resulting in good cell activation and avoiding spots at the formation interface.

[0057] Optionally, continue to refer to Figure 1 and Figure 2 As shown, the first magnetic component 22 and the second magnetic component 113 can be made of powerful magnets, such as neodymium iron boron magnets. Compared with ferrite magnets, AlNiCo and Samarium Cobalt, their magnetic properties far surpass those of other types of magnets. Neodymium iron boron magnets can attract a weight 640 times their own weight. Therefore, the first magnetic component 22 in the cover 2 can drive the second magnetic component 113 in the first partition 110, the second partition 111 and the third partition 112 to reciprocate along the first direction X.

[0058] It should be noted that: continue to refer to Figure 1 As shown, since the base plate 12 is an inclined plate, the height of the first partition 110 along the first direction X is h1, the height of the third partition 112 along the first direction X is h2, and the height of the second partition 111 along the first direction X is h3, where h1 > h2 > h3.

[0059] In one alternative embodiment, combined with Figure 1 and Figure 3As shown, the bottom plate 12 has a groove 5 on the side near the cover 2, corresponding to the first partition 110, the second partition 111, and the third partition 112. The bottom ends of the first partition 110, the second partition 111, and the third partition 112 are located in the groove 5. Specifically, the bottoms of the first partition 110, the second partition 111, and the third partition 112 can be placed in the groove 5. When the connector 21 in the cover 2 lifts the first partition 110, the second partition 111, and the third partition 112, the first partition 110, the second partition 111, and the third partition 112... The bottoms of the first partition 110 and the third partition 112 are directly detached from the groove 5 of the base plate 12; when the connector 21 in the cover 2 drives the first partition 110, the second partition 111 and the third partition 112 to fall, the bottoms of the first partition 110, the second partition 111 and the third partition 112 fall directly into the groove 5 of the base plate 12. By adopting the above solution, the first partition 110, the second partition 111 and the third partition 112 can be conveniently and quickly fixed to prevent the first partition 110, the second partition 111 and the third partition 112 from slipping.

[0060] In one alternative embodiment, Figure 6 This is a schematic diagram of the open state of the container body and the cover in another formation device provided by the present invention; Figure 7 This is a schematic diagram of the structure of the first, second, and third blocking plates provided by the present invention; continue referring to... Figure 6 and Figure 7 As shown, in this embodiment, at least three blocking devices 11 include a first blocking plate 114, a second blocking plate 115, and a third blocking plate 116. The first blocking plate 114 is used to block the release of electrolyte from the storage tank 3 between the first blocking plate 114 and the second blocking plate 115. The second blocking plate 115 is used to block the release of electrolyte from the storage tank 3 between the second blocking plate 115 and the third blocking plate 116. The third blocking plate 116 is used to block the release of electrolyte from the storage tank 3 between the third blocking plate 116 and the side wall 13 of the container body. The first blocking plate 114 is located on the side closer to the nozzle 4, the third blocking plate 116 is located on the side away from the nozzle 4, and the second blocking plate 115 is located between the first blocking plate 114 and the third blocking plate 116.

[0061] The first baffle plate 114, the second baffle plate 115, and the third baffle plate 116 each include a first sub-plate 1140 and a second sub-plate 1141 connected to the first sub-plate 1140. The first sub-plate 1140 and the second sub-plate 1141 can be rectangular in shape. The first sub-plate 1140 is connected to the side wall 13 of the container body. Optionally, the side wall of the first sub-plate 1140 is fixedly connected to the side wall 13 of the container body, and the bottom wall of the first sub-plate 1140 is fixedly connected to the bottom plate 12 of the container body 1. The bottom of the first sub-plate 1140 is provided with a liquid outlet 1140a. The second sub-plate 1141 reciprocates along the first direction X. The connector 21 in the container body 1 can drive the second sub-plate 1141 to reciprocate along the first direction X. When the connector 21 in the container body 1 lifts the second sub-plate 1141 along the first direction X, the electrolyte can flow out through the liquid outlet 1140a in the first sub-plate 1140.

[0062] The second sub-plate 1141 is provided with a third magnetic element 1141a that attracts the first magnetic element 22 on the side near the connector 21. The third magnetic element 1141a of the second sub-plate 1141 in the first blocking plate 114 is located in the middle of the first blocking plate 114. The third magnetic element 1141a of the second sub-plate 1141 in the second blocking plate 115 is located in the upper middle part of the second blocking plate 115. The third magnetic element 1141a of the second sub-plate 1141 in the third blocking plate 116 is located at the top of the third blocking plate 116. It can be understood that the third magnetic elements 1141a on the second sub-plate 1141 in the first blocking plate 114, the second sub-plate 1141 in the second blocking plate 115, and the second sub-plate 1141 in the third blocking plate 116 are designed from low to high. With this scheme, since the first magnetic component 22 is designed at the bottom of the connector 21 in the cover 2, and the third magnetic component 1141a on the second sub-plate 1141 in the first baffle plate 114, the second sub-plate 1141 in the second baffle plate 115, and the second sub-plate 1141 in the third baffle plate 116 are arranged sequentially from low to high, the connector 21 of the cover 2 can sequentially drive the second sub-plate 1141 in the first baffle plate 114, the second sub-plate 1141 in the second baffle plate 115, and the second sub-plate 1141 in the third baffle plate 116 to lift up, thereby sequentially releasing the electrolyte in the storage tank 3 near the tip 4 to the electrolyte in the storage tank 3 away from the tip 4. Specifically, first, the second sub-plate 1141 in the first baffle 114 is lifted to release the electrolyte in the storage tank 3 between the first baffle 114 and the second baffle 115; then, the second sub-plate 1141 in the second baffle 115 is lifted to release the electrolyte in the storage tank 3 between the second baffle 115 and the third baffle 116; finally, the second sub-plate 1141 in the third baffle 116 is lifted to release the electrolyte in the last storage tank 3.

[0063] Optionally, combined Figure 6 and Figure 7 As shown, the first magnetic component 22 and the third magnetic component 1141a can be made of powerful magnets, such as neodymium iron boron magnets. Compared with ferrite magnets, AlNiCo and Samarium Cobalt, their magnetic properties far surpass those of other types of magnets. Neodymium iron boron magnets can attract a weight 640 times their own weight. Therefore, the first magnetic component 22 in the cover 2 can drive the second sub-plate 1141 in the first blocking plate 114, the second sub-plate 1141 in the second blocking plate 115, and the second sub-plate 1141 in the third blocking plate 116 to reciprocate along the first direction X.

[0064] In one alternative embodiment, continue to refer to Figure 7 As shown, the area of ​​the flow port 1140a of the first sub-plate 1140 in the first baffle 114 is S1, the area of ​​the flow port 1140a of the first sub-plate 1140 in the second baffle 115 is S2, and the area of ​​the flow port 1140a of the first sub-plate 1140 in the third baffle 116 is S3, where S1 > S2 > S3. That is, the area of ​​the flow port 1140a of the first sub-plate 1140 in the first baffle 114, second baffle 115, and third baffle 116 decreases from large to small, thus... Electrolyte in different storage tanks 3 is released. When the cover 2 lifts the first baffle 114, because S1 is at its maximum, before the second baffle 115 is lifted, the electrolyte in the storage tank 3 between the first baffle 114 and the second baffle 115 can be quickly injected into the cell 6 through the nozzle 4. Before the third baffle 116 is lifted, because S2 is in the middle, the electrolyte in the storage tank 3 between the second baffle 115 and the third baffle 116 can also be quickly injected into the cell 6 through the nozzle 4.

[0065] Optionally, continue to refer to Figure 7As shown, the first sub-plate 1140 and the second sub-plate 1141 are connected by a guide rail assembly 1142. Specifically, the first sub-plate 1140 and the second sub-plate 1141 can be slidably connected by the guide rail assembly 1142. The guide rail assembly 1142 includes sliders 1142b and guide rails 1142a. For example, the guide rail 1142a is provided on the side of the first sub-plate 1140 near the second sub-plate 1141, and a pair of sliders 1142b that cooperate with the guide rail 1142a are provided on the side of the second sub-plate 1141 near the first sub-plate 1140. 142b can slide along the first direction X on the guide rail 1142a on the first sub-plate 1140, enabling the sequential release of electrolyte in each storage tank 3. Alternatively, depending on the actual situation, a pair of sliders can be provided on the side of the first sub-plate 1140 near the second sub-plate 1141, and a guide rail that cooperates with the sliders can be provided on the side of the second sub-plate 1141 near the first sub-plate 1140. The slider on the first sub-plate 1140 can slide along the first direction X on the guide rail on the second sub-plate 1141, which can also enable the sequential release of electrolyte in each storage tank 3. No specific limitation is made in this regard.

[0066] In one alternative embodiment, Figure 8 This is a schematic diagram of the open state of the container body and the cover in another formation apparatus provided by the present invention; Figure 9 This is a schematic diagram showing the open state of the container body and the lid in another formation apparatus provided by the present invention; see also Figure 8 and Figure 9 As shown, at least three liquid storage tanks 3 include a first liquid storage tank 31, a second liquid storage tank 32, and a third liquid storage tank 33. The first liquid storage tank 31 is located on the side closer to the nozzle 4, the third liquid storage tank 33 is located on the side away from the nozzle 4, and the second liquid storage tank 32 is located between the first liquid storage tank 31 and the second liquid storage tank 32. The number of the first liquid storage tank 31 and the second liquid storage tank 32 is at least two, and the number of the third liquid storage tank 33 is at least one.

[0067] Specifically, continue to refer to Figure 8 and Figure 9 As shown, at least three liquid storage tanks 3 include a first liquid storage tank 31, a second liquid storage tank 32, and a third liquid storage tank 33. The first liquid storage tank 31 is used to store one injection of electrolyte, which is used to maintain the performance of the temperature rise. The second liquid storage tank 32 is used to store lithium replenishing electrolyte, which is used to activate the lithium replenishing agent. The third liquid storage tank 33 is used to store two injections of electrolyte, which are used to maintain the cycle. The volumes of the first liquid storage tank 31, the second liquid storage tank 32, and the third liquid storage tank 33 are determined according to the amount of electrolyte injected into the battery cell, and no specific limitation is made in this regard.

[0068] The first liquid storage tank 31 is located near the tip 4, the third liquid storage tank 33 is located away from the tip 4, and the second liquid storage tank 32 is located between the first liquid storage tank 31 and the second liquid storage tank 32. The number of first liquid storage tanks 31 is greater than or equal to 2, the number of second liquid storage tanks 32 is greater than or equal to 2, and the number of third liquid storage tanks 33 is greater than or equal to 1. The volumes of the first liquid storage tank 31, the second liquid storage tank 32, and the third liquid storage tank 33 are different, and their volumes can follow a large, medium, or small trend. During the formation process, the electrolyte in the first liquid storage tank 31, the second liquid storage tank 32, and the third liquid storage tank 33 are released sequentially according to the actual situation. The electrolyte is released based on three dimensions: first, based on the cell film formation potential, different types of electrolyte can be released; second, based on the cell temperature setting, when the temperature inside the cell 6 is greater than 55°C, the same type of electrolyte can be released; and third, based on the long cycle of the cell, two injections of electrolyte are required.

[0069] The volume of the two first liquid storage tanks 31 can be larger on the side closer to the tip 4 than on the side farther from the tip 4. The electrolyte in the two first liquid storage tanks 31 can be released simultaneously. Taking the two first partitions 110 as an example, the positions of the first magnetic components 22 in the two first partitions 110 can be designed to be completely consistent. The volume of the two second liquid storage tanks 32 can be larger on the side closer to the first liquid storage tank 31 than on the side farther from the first liquid storage tank 31. The electrolyte in the two second liquid storage tanks 32 can be released simultaneously.

[0070] Optionally, continue to refer to Figure 1 and Figure 2 As shown, the materials of the cover 2, container body 1 and blocking device 11 all include heat-insulating materials. The heat-insulating materials have low thermal conductivity, high thermal resistance (effectively reducing heat transfer) and good high temperature resistance. By using heat-insulating materials for the cover 2, container body 1 and blocking device 11, heat transfer between the various liquid storage tanks 3 can be prevented, so as to maintain the internal normal temperature.

[0071] Figure 10 This is one of the schematic flowcharts of the formation method for battery cells provided by the present invention; Figure 11 This is the cell temperature rise curve provided by the present invention; combined with Figure 1 , Figure 2 , Figure 10 and Figure 11 As shown, this embodiment provides a formation method for a battery cell, which involves injecting electrolyte into the battery cell 6 using a formation apparatus, the formation apparatus including the aforementioned formation apparatus; the method includes the following steps:

[0072] Insert the nozzle 4 of the container body into the liquid injection hole of the cell 6, inject different electrolytes into different liquid storage tanks 3, and cover the container body with the cap 2; release the electrolyte in the corresponding area according to the cell temperature rise curve to complete the activation of the cell 6.

[0073] Specifically, in combination Figure 1 , Figure 2 and Figure 10 As shown, the electrolyte is injected into the cell 6 using the above-mentioned formation apparatus, including the following steps:

[0074] First, insert the nozzle 4 of the container body into the liquid injection hole of the cell 6, and inject different electrolytes into different storage tanks 3. After injecting the corresponding electrolytes into different storage tanks 3, close the container body with the cover 2. Of course, depending on the actual situation, you can also first inject different electrolytes into different storage tanks 3 in the container body, and then close the container body with the cover 2. Then insert the nozzle 4 of the container body into the liquid injection hole of the cell 6. Finally, send the formation device with the cell 6 connected to it to the formation cabinet for formation. The above order can be adjusted and is not specifically limited.

[0075] According to the cell temperature rise curve, the cover 2 is raised or the blocking device 11 is lowered to release the electrolyte in the corresponding area to complete the activation of the cell 6. If the reaction is violent and a lot of gas is produced at the film formation peak, a lot of gas production usually means that the internal resistance is large and the temperature rises quickly. At this time, the corresponding electrolyte needs to be released and injected into the cell 6 to control the gas production. At the same time as controlling the gas production, the internal temperature of the cell 6 can also be adjusted.

[0076] It should be noted that: Figure 11 The formation process of the conventional group and the release group is the same. For example, the constant current charging is first carried out at 0.02C (small current) for 3 hours, and then constant current charging is carried out at 0.1C (large current) for 3 hours. The electrolyte can be released in the release group between 45℃ and 55℃.

[0077] Compared with the prior art, the formation method for battery cells provided in this embodiment achieves at least the following beneficial effects:

[0078] The formation method for the battery cell in this embodiment involves injecting electrolyte into the battery cell 6 using the aforementioned formation device. The method includes the following steps: inserting the nozzle 4 of the container body into the injection hole of the battery cell 6; injecting different electrolytes into different storage tanks 3; and covering the container body with the cap 2. Electrolyte is released in the corresponding area according to the battery cell temperature rise curve to activate the battery cell 6. By adopting this scheme, electrolyte release at the corresponding position according to the battery cell temperature rise curve during the formation process not only replenishes the electrolyte but also adjusts the internal temperature of the battery cell 6, ensuring temperature stability during formation under high current, preventing excessively rapid internal temperature rise of the battery cell 6, and improving formation efficiency.

[0079] In one alternative embodiment, Figure 12 This is the second schematic flowchart of the cell formation method provided by the present invention. (In conjunction with...) Figure 1 , Figure 2 , Figure 11 and Figure 12 As shown, in this embodiment, releasing electrolyte in the corresponding region according to the cell temperature rise curve includes:

[0080] The electrolyte includes a primary electrolyte, a lithium replenishing electrolyte, and a secondary electrolyte. The primary electrolyte is injected into a first storage tank 31, the lithium replenishing electrolyte is injected into a second storage tank 32, and the secondary electrolyte is injected into a third storage tank 33. Based on the cell temperature rise, the primary electrolyte is released within a first charging current range; based on the cell temperature rise, the lithium replenishing electrolyte is released within a second charging current range; and based on the cell temperature rise, the secondary electrolyte is released within a discharge current range.

[0081] Specifically, the electrolyte includes a primary electrolyte, a lithium replenishing electrolyte, and a secondary electrolyte. The primary electrolyte is injected into the first storage tank 31 to ensure the internal temperature rise performance of the battery cell 6. The lithium replenishing electrolyte is injected into the second storage tank 32 to activate the lithium replenishing agent. The secondary electrolyte is injected into the third storage tank 33 to ensure the internal circulation performance of the battery cell 6.

[0082] A single electrolyte is released based on a first charging current range. This first charging current range may include a first sub-charging current range and a second sub-charging current range. Based on the assumption that the film formation potential and peak intensity do not change significantly, and according to the cell temperature rise, a single electrolyte is released based on the first sub-charging current range. The first sub-charging current range can be 0.02C to 0.2C. This can be understood as selecting a value between 0.02C and 0.2C based on the cell temperature rise. The cover 2 drives the first partition 110 or the first baffle 114 to release a single electrolyte stored in the first storage tank 31. Depending on the actual situation, the single electrolyte in the first storage tank 31 can be released multiple times. The cell temperature rise can be determined based on the electrolyte reaction characteristics, and the temperature range for this cell temperature rise is 50℃ to 100℃. Optionally, the temperature in this cell temperature rise can be 55℃. The above scheme can adjust the internal temperature of the cell 6 according to the electrolyte reaction characteristics.

[0083] Based on the assumption that the lithium intercalation potential and the intensity of the lithium intercalation peak do not change significantly, and according to the cell temperature rise state, the cover 2 drives the first partition 110 or the first baffle 114 to release a vial of electrolyte stored in the first storage tank 31. Depending on the actual situation, the vial of electrolyte in the first storage tank 31 can be released multiple times. The second sub-charging current range can be 0.1C to 1C. This can be understood as releasing a vial of electrolyte by selecting a value between 0.1C and 1C according to the cell temperature rise state. The temperature range during the cell temperature rise state is 20℃ to 100℃. Optionally, the temperature during the cell temperature rise state can be 45℃. The above scheme can adjust the internal temperature of the cell 6 according to the cell charging temperature rise characteristics.

[0084] Based on the assumption that the intensity of the lithium replenishment activation peak does not change significantly, and according to the cell temperature rise state, the first separator 110 and the second separator 111 are sequentially raised to release the lithium replenishing electrolyte, or the cover 2 is sequentially raised to release the first baffle 114 and the second baffle 115. Depending on the actual situation, the lithium replenishing electrolyte in the second storage tank 32 can be released multiple times until the lithium replenishing electrolyte in the second storage tank 32 is completely injected into the cell 6. Only then can the third separator 112 or the third baffle 116 be raised to release a second injection of electrolyte. The third charging current range can be 0.01C to 0.3C, and the temperature range during the cell temperature rise state is 20℃ to 100℃. Optionally, the temperature during the cell temperature rise state can be 55℃. The above scheme can control the internal temperature of the cell 6 according to the reaction characteristics of the lithium replenishing electrolyte.

[0085] During the cell temperature rise, the temperature range is 20℃ to 80℃. Optionally, the temperature during the cell temperature rise can be 45℃. The two injections of electrolyte are released based on the discharge current range, which can be 0.2C to 1C. This can be understood as: during the cell temperature rise, the temperature is 45℃, and two injections of electrolyte are released at a value between 0.2C and 1C. The above scheme can control the internal temperature of the cell 6 based on the cell's own discharge temperature rise.

[0086] The above scheme not only ensures the formation effect of lithium-ion batteries, but also minimizes the formation time. For example, the total time of the lithium-ion activation stage in the above scheme is reduced by half compared to the conventional lithium-ion laser stage, thereby increasing battery production capacity. At the same time, it can also reduce the use of formation cabinets and reduce costs.

[0087] It should be noted that 0.02C~0.2C, 0.1C~1C, 0.01C~0.3C, and 0.2C~1C represent the charge / discharge rate of the battery, which can be calculated by dividing the charge / discharge current by the rated capacity of the cell.

[0088] In one alternative embodiment, Figure 13 This is the third schematic flowchart of the cell formation method provided by the present invention. Figure 1 , Figure 2 , Figure 11 and Figure 13 As shown, the release of electrolyte in the corresponding region according to the cell temperature rise curve includes:

[0089] The electrolyte includes a first electrolyte, a lithium replenishing electrolyte, and a second electrolyte. The first electrolyte is injected into the first storage tank 31, the second electrolyte is injected into the second storage tank 32, and the lithium replenishing electrolyte is injected into the third storage tank 33.

[0090] Based on the cell temperature rise status, one injection of electrolyte is released based on the first potential range, one injection of electrolyte and two injections of electrolyte are released sequentially based on the second potential range, and lithium replenishing electrolyte is released based on the third potential range. The first potential range is smaller than the second potential range, and the second potential range is smaller than the third potential range.

[0091] Specifically, the electrolyte includes a primary electrolyte, a lithium replenishing electrolyte, and a secondary electrolyte. The primary electrolyte is injected into the first storage tank 31 to ensure the internal temperature rise performance of the battery cell 6. The secondary electrolyte is injected into the second storage tank 32 to ensure the internal circulation performance of the battery cell 6. The lithium replenishing electrolyte is injected into the third storage tank 33 to activate the lithium replenishing agent.

[0092] During the cell temperature rise, the temperature can be between 45℃ and 55℃. Based on this, the first potential range can be before 3.3V, the second potential range can be between 3.3V and 3.65V, and the third potential range can be between 36.5V and 4.2V. Specifically, charging at 0.1C to 3.0V cutoff and charging at 0.2C to 3.3V cutoff will raise the cover 2 according to the cell temperature rise, thereby driving the first partition 110 or the first baffle 114 to release a bottle of electrolyte stored in the first storage tank 31. Depending on the actual situation, the bottle of electrolyte in the first storage tank 31 can be released multiple times. A large current is used to shorten the formation time, but it should not affect film formation. During the entire high-current charging process, if the internal temperature of the cell 6 exceeds the limit (e.g., the internal temperature of the cell 6 is 45℃, 47℃, 49℃, 51℃, 53℃, or 55℃), a bottle of electrolyte can also be released.

[0093] When charging from 0.3C to 3.65V, cover 2 first lifts the first partition 110 or the first baffle 114 to release one electrolyte from the first storage tank 31. After the first electrolyte is released, the second electrolyte is released. When releasing the second electrolyte, cover 2 needs to lift the first partition 110 and the second partition 111 in sequence, or lift the first baffle 114 and the second baffle 115 in sequence, to maximize the internal circulation performance of the cell 6. During the entire high-current charging process, if the internal temperature of the cell 6 exceeds the limit (e.g., the internal temperature of the cell 6 is 45℃, 47℃, 49℃, 51℃, 53℃ or 55℃), one electrolyte can be released first, followed by the second electrolyte. It should be noted that the second electrolyte is released only after the first electrolyte is released.

[0094] When charging to 4.2V (0.1C), the cover 2 sequentially lifts the first separator 110, the second separator 111, and the third separator 112 to release the lithium replenishing electrolyte. Alternatively, the cover 2 sequentially lifts the first baffle 114, the second baffle 115, and the third baffle 116 to release the lithium replenishing electrolyte. Depending on the actual situation, the lithium replenishing electrolyte in the third storage tank 33 can be released multiple times to shorten the formation time as much as possible. During the entire high-current charging process, if the internal temperature of the cell 6 exceeds the limit (e.g., the internal temperature of the cell 6 is 45℃, 47℃, 49℃, 51℃, 53℃, or 55℃), the lithium replenishing electrolyte can be released.

[0095] The above scheme not only ensures the formation effect of lithium-ion batteries, but also minimizes the formation time. For example, the total time of the lithium-ion activation stage in the above scheme is reduced by half compared to the conventional lithium-ion laser stage, thereby increasing battery production capacity. At the same time, it can also reduce the use of formation cabinets and reduce costs.

[0096] As can be seen from the above embodiments, the formation apparatus and formation method for battery cells provided by the present invention achieve at least the following beneficial effects:

[0097] The present invention provides a formation apparatus and a formation method for battery cells. The formation apparatus includes a container body and a cover connected to the container body. At least three blocking devices are disposed within the container body, dividing the container body into at least three liquid storage tanks, each containing a different electrolyte. At least three connectors are disposed on the side of the cover near the container body, corresponding to and connected to the blocking devices, and driving the blocking devices to reciprocate along a first direction, which is from the cover towards the container body. A nozzle extends from the lower end of the container body for sealing with the battery cell's electrolyte injection hole. This design not only allows for the simultaneous storage of several different types of electrolytes, thus achieving integrated electrolyte injection, but also enables the release of different types of electrolyte into the battery cell. This allows for electrolyte replenishment while simultaneously adjusting the internal temperature of the battery cell, ensuring temperature stability during formation under high current, thereby preventing excessively rapid internal temperature rise and improving the formation effect and performance of the battery cell.

[0098] While specific embodiments of the invention have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A formation apparatus, characterized in that, The container includes a container body and a cover connected to the container body. The container body is provided with at least three blocking devices, which divide the container body into at least three liquid storage tanks, each of which contains a different electrolyte. The cover is provided with at least three connectors on the side near the container body. The connectors correspond to the blocking device, are connected to the blocking device, and drive the blocking device to reciprocate along a first direction, which is from the cover to the container body. The lower end of the container body extends a pointed nozzle for sealing with the battery cell's liquid injection hole; The container body also includes a bottom plate, which is inclined towards the lid from the side near the nozzle; a first magnetic element is provided on the side of the connector near the blocking device, and the first magnetic element is located at the bottom of the connector; At least three of the aforementioned blocking devices include a first partition, a second partition, and a third partition. The first partition is located near the tip, the third partition is located away from the tip, and the second partition is located between the first and second partitions. The first, second, and third partitions reciprocate along the first direction. Second magnetic elements that attract the first magnetic element are disposed on the first, second, and third partitions. Specifically, the second magnetic element in the first partition is located in the middle of the first partition, the second magnetic element in the second partition is located in the upper-middle part of the second partition, and the second magnetic element in the third partition is located at the top of the third partition. Alternatively, At least three of the aforementioned blocking devices include a first blocking plate, a second blocking plate, and a third blocking plate. The first blocking plate is located near the nozzle, the third blocking plate is located away from the nozzle, and the second blocking plate is located between the first and second blocking plates. Each of the first, second, and third blocking plates includes a first sub-plate and a second sub-plate connected to the first sub-plate. The first sub-plate is connected to the side wall of the container body, and a flow port is provided at the bottom of the first sub-plate. The second sub-plate reciprocates along the first direction. A third magnetic element is provided on the side of the second sub-plate near the connector, which attracts the first magnetic element. Specifically, the third magnetic element of the second sub-plate in the first blocking plate is located in the middle of the first blocking plate, the third magnetic element of the second sub-plate in the second blocking plate is located in the upper middle part of the second blocking plate, and the third magnetic element of the second sub-plate in the third blocking plate is located at the top of the third blocking plate.

2. The formation apparatus according to claim 1, characterized in that, When at least three of the blocking devices include a first partition, a second partition, and a third partition, with the first partition located near the tip, the third partition located away from the tip, and the second partition located between the first and second partitions, and the first, second, and third partitions reciprocating along the first direction; and the first, second, and third partitions are provided with second magnetic elements that attract the first magnetic element, wherein the second magnetic element in the first partition is located in the middle of the first partition, the second magnetic element in the second partition is located in the upper middle part of the second partition, and the second magnetic element in the third partition is located at the top of the third partition, the bottom plate near the cover body has a groove corresponding to the first, second, and third partitions, and the bottom ends of the first, second, and third partitions are located within the groove.

3. The formation apparatus according to claim 1, characterized in that, When at least three blocking devices include a first blocking plate, a second blocking plate, and a third blocking plate, the first blocking plate is located near the nozzle, the third blocking plate is located away from the nozzle, and the second blocking plate is located between the first blocking plate and the second blocking plate; each of the first, second, and third blocking plates includes a first sub-plate and a second sub-plate connected to the first sub-plate, the first sub-plate is connected to the side wall of the container body, and a flow port is provided at the bottom of the first sub-plate; the second sub-plate reciprocates along the first direction; the second sub-plate is positioned near the connector. A third magnetic element is attracted to the first magnetic element. The third magnetic element of the second sub-plate in the first blocking plate is located in the middle of the first blocking plate. The third magnetic element of the second sub-plate in the second blocking plate is located in the upper middle part of the second blocking plate. When the third magnetic element of the second sub-plate in the third blocking plate is located at the top of the third blocking plate, the area of ​​the liquid outlet of the first sub-plate in the first blocking plate is S1, the area of ​​the liquid outlet of the first sub-plate in the second blocking plate is S2, and the area of ​​the liquid outlet of the first sub-plate in the third blocking plate is S3, wherein S1 > S2 > S3.

4. The formation apparatus according to claim 1, characterized in that, The at least three liquid storage tanks include a first liquid storage tank, a second liquid storage tank, and a third liquid storage tank. The first liquid storage tank is located on the side closer to the nozzle, the third liquid storage tank is located on the side farther from the nozzle, and the second liquid storage tank is located between the first liquid storage tank and the second liquid storage tank. The number of the first liquid storage tank and the second liquid storage tank is at least two, and the number of the third liquid storage tank is at least one.

5. A method for forming a battery cell using the formation apparatus according to any one of claims 1-4, characterized in that, Electrolyte is injected into the battery cell using the formation device; Insert the pointed tip of the container body into the electrolyte injection hole of the battery cell, inject different electrolytes into different storage tanks, and then cover the container body with the cap. Electrolyte is released in the corresponding region according to the cell temperature rise curve to complete cell activation.

6. The method for forming a battery cell according to claim 5, characterized in that, The step of releasing electrolyte in the corresponding region according to the cell temperature rise curve includes: The electrolyte includes a first electrolyte, a lithium-replenishing electrolyte, and a second electrolyte. The first electrolyte is injected into a first storage tank, the lithium-replenishing electrolyte is injected into a second storage tank, and the second electrolyte is injected into a third storage tank. Based on the cell temperature rise status, the electrolyte is released according to the first charging current range; Based on the cell temperature rise status, the lithium replenishing electrolyte is released according to the second charging current range; Based on the cell temperature rise status, the two electrolyte injections are released according to the discharge current range.

7. The method for forming a battery cell according to claim 6, characterized in that, The step of releasing electrolyte in the corresponding region according to the cell temperature rise curve includes: The electrolyte includes a first electrolyte, a lithium replenishing electrolyte, and a second electrolyte. The first electrolyte is injected into a first storage tank, the second electrolyte is injected into a second storage tank, and the lithium replenishing electrolyte is injected into a third storage tank. Based on the cell temperature rise status, the first injection of electrolyte is released based on a first potential range, the first injection of electrolyte and the second injection of electrolyte are released sequentially based on a second potential range, and the lithium replenishing electrolyte is released based on a third potential range, wherein the first potential range is smaller than the second potential range, and the second potential range is smaller than the third potential range.

Images