Pre-lithiation device of pole piece

Abstract

The utility model provides a pre-lithiation device of a pole piece, comprising: a box body, the box body comprising a first placement area and a second placement area; the second placement area is arranged around the first placement area, and the second placement area is configured to accommodate pole pieces; an opening is formed in the top of the box body, and the top cover is matched with the opening of the box body; the lithium source is positioned in the first placement area; a gap is formed between the lithium source and the pole piece; the interior of the box body is divided into the first placement area and the second placement area, reasonable distribution of the internal space of the box body and batch treatment of the pole pieces are achieved, it is guaranteed that an SEI film with the high compact degree and the good uniformity degree can be formed on the surfaces of the pole pieces, and therefore the pre-lithiation treatment efficiency of the pole pieces is improved; and the top cover is matched for use, so that the opening of the box body can be blocked, the interference of the external environment on the pre-lithiation process is reduced, the heat preservation effect of the box body is improved, and the quality of the pole piece subjected to pre-lithiation treatment is favorably improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a pre-lithiation device for a pole piece. Background Art

[0002] Lithium batteries are widely used in various fields and have broad development prospects. In order to improve the energy density and cycle life of batteries, it is usually necessary to perform electrochemical pre-lithiation on the negative electrode sheets of lithium batteries to pre-form an SEI film (Solid Electrolyte Interphase) on the surface of the negative electrode sheets, thereby reducing the battery's consumption of active lithium in the positive electrode during the first cycle. Currently, the mainstream electrochemical pre-lithiation treatments include assembling pre-lithiated cells and pre-lithiating the sheets. However, in related technologies, the equipment used to implement electrochemical pre-lithiation treatments is relatively complex, and the specifications of the negative electrode sheets are relatively restricted. Therefore, it is difficult to process the negative electrode sheets in batches, thereby affecting the pre-lithiation efficiency of the negative electrode sheets. Utility Model Content

[0003] In view of this, the purpose of this application is to propose a pre-lithiation device for an electrode to solve some or all of the technical problems mentioned above.

[0004] Based on the above objectives, the present application provides a pre-lithiation device for a pole piece, comprising:

[0005] A box body, the box body comprising a first placement area for accommodating electrolyte and a second placement area; the second placement area surrounds the first placement area, and the second placement area is configured to accommodate the electrode;

[0006] A top cover, which is arranged on the top of the box body and is adapted to the box body;

[0007] A lithium source is located in the first placement area; and the lithium source and the second placement area are arranged in a gap.

[0008] As can be seen from the above, the pre-lithiation device for the electrode provided in the present application includes a box, a top cover and a lithium source, which has a simple structure and is easy to operate; by dividing the interior of the box into a first placement area and a second placement area, and placing the lithium source in the first placement area and the rolled electrode in the second placement area, a rational allocation of the internal space of the box is achieved, so that electrodes of different specifications can be processed in batches, ensuring that the lithium source provides sufficient lithium ions to the electrode through the electrolyte, which is conducive to the formation of a highly dense and well-uniform SEI film on the surface of the electrode, thereby improving the pre-lithiation efficiency of the electrode and its surface quality; by providing a top cover at the opening of the box, the degree of interference of the external environment on the pre-lithiation process can be reduced, the thermal insulation performance of the box can be improved, and the pre-lithiation treatment effect of the electrode can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in this application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, the drawings described below are merely embodiments of this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0010] Figure 1 Schematic diagram of the structure of the pre-lithiation device in this application;

[0011] Figure 2 This is a diagram of the usage state of the pre-lithiation device in this application;

[0012] Figure 3 This is a schematic diagram of the distribution of a pole piece in the box in this application;

[0013] Figure 4 Schematic diagram of the connection relationship between the pre-lithiation device and the power supply in this application;

[0014] Figure 5 Schematic cross-section of the box body and the first fixing protrusion in this application;

[0015] Figure 6 This is a cross-sectional schematic diagram of the box body and the first fixing groove in this application;

[0016] Figure 7 This is a schematic diagram of the three-dimensional structure of a top cover in this application;

[0017] Figure 8 is a cross-sectional schematic diagram of the top cover and the second fixing protrusion in this application;

[0018] Figure 9 Schematic cross-section of the top cover and the second fixing groove in this application;

[0019] Figure 10 This is a schematic diagram of the electrolyte circulation structure in this application.

[0020] Description of reference numerals:

[0021] 10. Pre-lithiation device;

[0022] 100, housing; 101, first fixing portion; 1011, first fixing protrusion; 1012, first fixing groove; 103, liquid inlet port; 104, liquid outlet port; 105, first cavity; 106, second cavity; 110, first placement area; 120, second placement area;

[0023] 200, top cover; 201, spring clip; 202, second fixing portion; 2021, second fixing protrusion; 2022, second fixing groove; 203, exhaust component; 204, temperature sensor; 205, liquid level sensor;

[0024] 300, lithium source; 301, lithium source installation part;

[0025] 400, electrolyte circulation assembly; 401, stop valve; 410, first pipeline; 420, second pipeline; 430, liquid reservoir; 440, pump body;

[0026] 20. Power supply;

[0027] 30. Pole piece; 31. Tab;

[0028] 40. Reel; 41. Through hole. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of this application more clear, this application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0030] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should have the usual meanings understood by people with ordinary skills in the field to which this application belongs. The "first", "second" and similar words used in the embodiments of the present application do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0031] The following is combined with Figures 1-10 The embodiments of the present application will be described in detail.

[0032] As far as lithium batteries are concerned, the negative electrode active material is the key to improving the energy density and cycle life of lithium batteries. Graphite negative electrode materials or silicon negative electrode materials are common negative electrode active materials. Among them, although graphite materials have the advantages of high capacity, low potential and high rate performance, there will be a SEI film that consumes active lithium during the first cycle of the battery. If the SEI film is damaged, it is easy to cause problems such as dead lithium in subsequent cycles, resulting in a large loss of reversible capacity in the later stage of the battery cycle. The volume change of silicon-based negative electrode materials is more obvious during the cycle, which is easy to cause frequent damage and regeneration of the SEI film, thereby leading to the loss of active lithium. Therefore, the formation of a dense SEI film on the surface of the negative electrode of the lithium battery plays a vital role in reducing the loss of active lithium and improving the performance of the negative electrode of the battery.

[0033] Currently, mainstream pre-lithiation methods include lithium alloy additive pre-lithiation, electrochemical pre-lithiation, lithium metal powder pre-lithiation, lithium foil pre-lithiation, and chemical pre-lithiation. Electrochemical pre-lithiation is widely used because it allows precise control of the speed and extent of pre-lithiation and offers high lithiation efficiency. Electrochemical pre-lithiation of the lithium battery's negative electrode can pre-form a high-performance SEI film, preventing the consumption of active lithium from the positive electrode during the first cycle. This reduces the risk of SEI film rupture and regeneration in later cycles, thereby increasing the battery's cycle life.

[0034] Currently, electrochemical pre-lithiation devices are divided into two forms. One is to assemble pre-lithiation batteries, that is, to construct a pre-lithiation positive electrode, combine the negative electrode plate with it to form a battery and inject electrolyte, and control the voltage and current for electrochemical treatment; however, the use of assembled pre-lithiation batteries is likely to cause a large amount of material waste, increase the investment in positive electrode plates, diaphragms, electrolytes, container construction and labor costs; the other is plate pre-lithiation, that is, immerse the negative electrode plate in the electrolyte, and then add a lithium source for electrochemical pre-lithiation, but the use of plate pre-lithiation is likely to limit the plate size, and cannot meet the pre-lithiation of longer plates in wound batteries, so the pre-lithiation processing efficiency is low.

[0035] In view of this, the present application provides a pre-lithiation device 10 for a pole piece 30, comprising a box body 100, a top cover 200 and a lithium source 300; the box body 100 comprises a first placement area 110 and a second placement area 120; the second placement area 120 is arranged around the first placement area 110, and the second placement area 120 is configured to accommodate the pole piece 30; an opening is provided at the top of the box body 100, and the top cover 200 is adapted to the opening of the box body 100; the lithium source 300 is located in the first placement area 110; and a gap is arranged between the lithium source 300 and the pole piece 30.

[0036] Specifically, see Figure 1-Figure 3 ;in, Figure 1 is a schematic structural diagram of the pre-lithiation device 10 in this application, Figure 2 This is a diagram showing the use status of the pre-lithiation device 10 in this application. Figure 3 Schematic diagram of the distribution of the pole pieces 30 in the box 100 in this application.

[0037] The present application provides a pre-lithiation device 10 for a pole piece 30, which can perform batch pre-lithiation treatment on the negative pole pieces 30 of a lithium battery to improve the energy density and cycle life of the lithium battery; more specifically, the pre-lithiation device 10 may include a box body 100 and a box cover, and the box body 100 is used to accommodate the electrolyte required in the pre-lithiation process; the box body 100 also includes a first placement area 110 and a second placement area 120, and the second placement area 120 is arranged around the first placement area 110, and the second placement area 120 is used to accommodate the pole piece 30 so that the rolled pole piece 30 is located inside the box body 100, thereby realizing the rational use of the internal space of the box body 100.

[0038] In addition, an opening is provided at the top of the box body 100 to connect the box body 100 with the external environment, making it convenient to place the electrode 30 inside the box body 100 or take it out from the box body 100; the top cover 200 is provided on the top of the box body 100 and is adapted to the opening of the box body 100, and is used to seal the opening of the box body 100, thereby reducing the interference of the external environment on the pre-lithiation process, improving the thermal insulation capacity of the box body 100, and preventing the external environment from polluting the electrolyte, thereby ensuring the pre-lithiation effect of the electrode 30.

[0039] The pre-lithiation device 10 also includes a lithium source 300 for providing lithium ions to the box 100; wherein the lithium source 300 is arranged in the box 100 and is located in the first placement area 110, so that the rolled pole piece 30 located in the second placement area 120 is arranged around the lithium source 300, realizing a rational distribution of the pole piece 30 and the lithium source 300, and improving the utilization rate of the internal space of the box 100; the lithium source 300 is located in the first placement area 110 and there is a gap between the lithium source 300 and the pole piece 30, that is, the lithium source 300 located in the first placement area 110 does not contact the pole piece 30 in the second placement area, thereby preventing a short circuit between the lithium source 300 and the pole piece 30 and causing damage to the pre-lithiation device 10.

[0040] Combine Figure 2The working principle of the pre-lithiation device 10 provided in the present application can be further elaborated; specifically, when the electrode 30 is pre-lithiated, sufficient electrolyte can be added to the box 100, and the lithium source 300 is placed in the first placement area 110, and the rolled electrode 30 is placed in the second placement area 120 in the box 100, so that the lithium source 300 and the electrode 30 are both immersed in the electrolyte; at this time, the electrode 30 is located in the second placement area 120 and is arranged around the lithium source 300, and there is a gap between the electrode 300 and the lithium source 300; at the same time, the top cover 200 is covered on the opening at the top of the box 100 to seal the opening of the box 100 and improve the thermal insulation effect of the box 100; wherein, the standing time of the electrode 30 in the electrolyte does not exceed 72 hours, and the standing time is 24 hours. The temperature range can be -20℃-65℃ (the optimal temperature is 45℃); then the lithium source 300 and the electrode 30 are energized to make the pre-lithiation device 10 and the electrode 30 form a battery structure, at this time the lithium source 300 is the positive electrode and the electrode 30 is the negative electrode; illustratively, the battery structure can be charged with a charging current of 0.1C (C is the rate of the rated capacity of the battery structure) for 7 minutes, and then the charging is stopped and left to stand for 5 minutes so that the lithium source 300 can provide sufficient lithium ions to the electrolyte, and then continue charging with a charging current of 1 / 3C until the SOC of the negative electrode of the battery structure (i.e., the electrode 30) reaches 30%, so that the lithium ions can be transferred to the surface of the electrode 30 and form a SEI film with good density on the surface of the electrode 30.

[0041] In addition, when the electrode 30 is pre-lithiated, the electrolyte in the box 100 can be driven to flow at a suitable flow rate through a delivery pump or other device, which can alleviate the difference in lithium ion concentration in the electrolyte, enhance the uniformity of the pre-lithiation of the electrode 30, and at the same time expel the bubbles attached to the electrolyte and the surface of the electrode 30, thereby improving the quality of the pre-lithiation treatment.

[0042] The electrolyte is further described in conjunction with the above embodiments; the electrolyte may include an electrolyte solvent and an electrolyte solute, wherein the electrolyte solvent may be a solvent material such as ethylene carbonate, propylene carbonate, diethyl carbonate, dimethyl carbonate and ethyl methyl carbonate, and the electrolyte solute may be a solvent material such as lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis(trifluoromethanesulfonyl)imide and lithium bis(fluorosulfonyl)imide. The electrolyte formed by the aforementioned electrolyte solvent and electrolyte solute has strong stability, good wetting effect, and can form a denser and more efficient SEI film, which will not be repeated here.

[0043] In some embodiments, the pre-lithiation device 10 is connected to a power source 20 ; when the electrode 30 is pre-lithiation treated, the lithium source 300 is electrically connected to the positive electrode of the power source 20 , and the electrode 30 is electrically connected to the negative electrode of the power source 20 .

[0044] Specifically, see Figure 4 ;in, Figure 4 Schematic diagram of the connection relationship between the pre-lithiation device 10 and the power source 20 in this application.

[0045] As for the pre-lithiation device 10, Figure 4 As shown, when the electrode 30 is pre-lithiated, it is necessary to energize the lithium source 300 and the electrode 30 so that the lithium ions in the electrolyte are transferred to the surface of the electrode 30 by the pre-lithiation device 10 to form an SEI film, thereby achieving the pre-lithiation of the electrode 30; Figure 4 As shown, the pre-lithiation device 10 can be connected to a power source 20, and the power source 20 provides electrical energy to the lithium source 300 in the pre-lithiation device 10 and the electrode 30 therein; when the electrode 30 is pre-lithiation treated, the positive electrode of the power source 20 can be electrically connected to the lithium source 300 inside the pre-lithiation device 10, and the negative electrode of the power source 20 can be electrically connected to the electrode 30 located in the box 100. At this time, a battery structure is formed between the pre-lithiation device 10 and the electrode 30; when the power source 20 is used to power the pre-lithiation device 10, the lithium source 300 is the positive electrode of the battery structure, and the electrode 30 is the negative electrode of the battery structure. When the power source 20 is turned on, lithium ions can be provided to the electrolyte through the lithium source 300, and the lithium ions can be transferred to the surface of the electrode 30 through the electrolyte to form a dense SEI film, thereby achieving the purpose of pre-lithiation treatment of the electrode 30.

[0046] In some embodiments, a plurality of spring clips 201 are provided at the bottom of the top cover 200, and the plurality of spring clips 201 are electrically connected to the negative pole of the power supply 20; when the top cover 200 is closed on the box body 100, the plurality of spring clips 201 are located inside the box body 100, and at least some of the spring clips 201 are clamped on the pole ear 31 of the pole piece 30 and are electrically connected to the pole piece 30.

[0047] Specifically, see Figure 7 and Figure 8 ,in, Figure 7 This is a schematic diagram of the three-dimensional structure of a top cover 200 in this application. Figure 8 This is a cross-sectional diagram of the top cover 200 and the second fixing protrusion 2021 in this application. Figure 9 It is a cross-sectional schematic diagram of the top cover 200 and the second fixing groove 2022 in this application.

[0048] As for the top cover 200 in the pretreatment device, the top cover 200 is adapted to the opening on the top of the box 100, and can seal the box 100 during the pretreatment process of the electrode 30 to improve the thermal insulation performance of the box 100; Figure 1-Figure 4 、 Figure 7 as well as Figure 8As shown, a plurality of spring clips 201 can be provided at the bottom of the top cover 200. Since the thickness of the electrode 30 is relatively thin (typically 70 μm-120 μm), before the electrode 30 is pre-lithiation treated, at least part of the spring clips 201 can be clamped on the electrode ear 31 of the electrode 30 to ensure that after the top cover 200 is closed on the top of the box body 100, the second electrode 30 located in the second placement area 120 inside the box body 100 can always remain in an unfolded state to prevent the electrode 30 from wrinkling or damage, and to enable the surface of the electrode 30 to be fully infiltrated by the electrolyte to ensure that a well-uniform SEI film can be formed on the surface of the electrode 30.

[0049] In addition, as for the spring clip 201 provided at the bottom of the top cover 200, multiple spring clips 201 are electrically connected to the negative pole of the power supply 20, and some spring clips 201 are clamped on the pole ear 31 of the pole piece 30, so that it can clamp and fix the pole piece 30 while also being electrically connected to the negative pole of the power supply 20, thereby making the pole piece 30 serve as the negative pole of the battery structure; when the external power supply 20 is used to provide electrical energy, the lithium ions in the electrolyte can move toward the surface of the pole piece 30, thereby forming a relatively uniform SEI film on the surface of the pole piece 30.

[0050] In some embodiments, the bottom wall of the box 100 is provided with a first fixing portion 101, and the first fixing portion 101 is detachably connected to a reel 40, and the reel 40 is provided with at least one layer of pole pieces 30 around its circumference;

[0051] As for the pre-lithiation device 10, in order to realize batch processing of the electrode 30 and enable the pre-lithiation device 10 to process electrode 30 of more specifications, the electrode 30 can be arranged in a roll shape to ensure that after the electrode 30 is placed inside the box 100, the roll 40 can be placed in the second placement area 120 without contacting the lithium source 300 in the first placement area 110; more specifically, as Figure 2 and Figure 3 As shown, before the electrode 30 is placed in the box 100, a reel 40 can be provided, and the electrode 30 can be wound on the surface of the reel 40 to form a rolled structure of the electrode 30; by adopting the reel 40, it is convenient to place the electrode 30 in batches inside the box 100, and ensure that the electrode 30 can be distributed in the second placement area 120; at the same time, the reel 40 can also block the first placement area 110 and the second placement area 120 in the box 100 to prevent the lithium source 300 from contacting the electrode 30 and causing a short circuit.

[0052] In addition, if Figure 1 、 Figure 2 as well as Figure 4As shown, with respect to the box body 100, a first fixing portion 101 can be provided at the bottom of the box body 100, and the first fixing portion 101 is adapted to the bottom end of the reel 40. The reel 40 can be limited by the first fixing portion 101 to ensure that the electrode 30 can be located in the second placement area 120, which is beneficial to improving the stability of the installation of the reel 40 in the box body 100; since the first fixing portion 101 and the end of the reel 40 are detachably connected, it is convenient to place the electrode 30 that has not undergone pre-lithiation treatment in the box body 100, and it is also convenient to take out the electrode 30 that has undergone pre-lithiation treatment from the box body 100.

[0053] In some embodiments, the first fixing portion 101 is a first fixing protrusion 1011 that protrudes toward the direction close to the top cover 200 , or is a first fixing groove 1012 that is recessed toward the direction away from the top cover 200 .

[0054] Specifically, see Figure 5 and Figure 6 ,in, Figure 5 This is a cross-sectional diagram of the box body 100 and the first fixing protrusion 1011 in this application. Figure 6 It is a cross-sectional schematic diagram of the box body 100 and the first fixing groove 1012 in this application.

[0055] As for the first fixing portion 101, the first fixing portion 101 is provided on the bottom wall of the box body 100. The first fixing portion 101 is adapted to the end of the reel 40 and is detachably connected to the reel 40, so as to limit and install the reel 40 and reduce the difficulty of taking the electrode 30. Specifically, Figure 5 and Figure 6 As shown, when the first fixing portion 101 is a first fixing protrusion 1011 or a first fixing groove 1012 , the aforementioned effect can be achieved.

[0056] For example, Figure 5 As shown, the first fixing portion 101 can be a first fixing protrusion 1011 protruding toward the direction close to the top cover 200; when installing the reel 40 with the pole piece 30, the reel 40 can be placed inside the box 100 so that the bottom end of the reel 40 is sleeved on the first fixing protrusion 1011, thereby completing the installation of the reel 40; it should be noted that, as far as the first fixing protrusion 1011 is concerned, the first fixing protrusion 1011 can be set to a raised columnar or ring shape, both of which can achieve the limiting and fixing effect of the reel 40.

[0057] For example, Figure 6As shown, the first fixing portion 101 can also be a first fixing groove 1012 that is recessed in the direction away from the top cover 200; when installing the reel 40 with the pole piece 30, the reel 40 can be placed inside the box 100 so that the bottom end of the reel 40 is inserted into the first fixing groove 1012, thereby completing the installation of the reel 40; it should be noted that, as far as the first fixing groove 1012 is concerned, the first fixing groove 1012 can be set to be a recessed columnar or annular shape, both of which can achieve the limiting and fixing effect of the reel 40.

[0058] In some embodiments, a lithium source mounting portion 301 is provided on the bottom wall of the box 100 . The lithium source mounting portion 301 is adapted to fit the lithium source 300 , and a gap is formed between the lithium source 300 and the reel 40 .

[0059] As for the lithium source 300, when the electrode 30 is pre-lithiated, a battery structure can be formed between the electrode 30 and the lithium source 300, and the lithium source 300 continuously provides lithium ions to the electrolyte, so that the lithium ions are transferred to the surface of the electrode 30 to form a dense SEI film; during the pre-lithiation process, since the lithium source 300 is continuously consumed, when the lithium source 300 cannot provide sufficient lithium ions, it needs to be replaced; Figures 1-6 As shown, by providing a lithium source mounting portion 301 on the bottom wall of the box body 100 and making the lithium source mounting portion 301 compatible with the lithium source 300, the stability of the installation of the lithium source 300 can be improved, and a detachable connection can be achieved between the lithium source 300 and the lithium source mounting portion 301; specifically, when the lithium source 300 is replaced or installed, the lithium source 300 can be taken out from the lithium source mounting portion 301 in the box body 100, and the new lithium source 300 can be placed in the lithium source mounting portion 301, and the lithium source mounting portion 301 provides a corresponding installation position for the lithium source 300; illustratively, the lithium source mounting portion 301 can be provided in a groove shape, which can limit the position of the lithium source 300 in the box body 100, and avoid the lithium source 300 from shaking or shifting when the electrolyte flows; and by arranging a gap between the lithium source 300 and the reel 40, the lithium source 300 is avoided from contacting the reel 40 to cause a short circuit problem of the lithium source 300.

[0060] In some embodiments, a second fixing portion 202 is provided at the bottom of the top cover 200 , and the second fixing portion 202 is detachably connected to a reel 40 , and the reel 40 is provided with at least one layer of pole pieces 30 around its circumference;

[0061] As for the electrode 30, the electrode 30 can be wound on the surface of the reel 40 using the reel 40 so that the rolled electrode 30 can be placed inside the box 100 at one time, ensuring that after the electrode 30 is placed inside the box 100, the electrode 30 can be distributed in the second placement area 120, and the electrode 30 and the lithium source 300 can be reasonably distributed in the box 100.

[0062] As for the top cover 200, Figure 1 and Figure 2 As shown, a second fixing portion 202 is provided at the bottom of the top cover 200, and the second fixing portion 202 is adapted to the top end of the reel 40. The position of the reel 40 can be restricted by the second fixing portion 202 to ensure that when the electrode 30 is placed inside the box 100, the electrode 30 can be in the second placement area 120, which is beneficial to improving the stability of the reel 40 inside the box 100; since the second fixing portion 202 and the end of the reel 40 are detachably connected, it is convenient to assemble the electrode 30 that has not undergone pre-lithiation treatment on the second fixing portion 202, and it is also convenient to remove the electrode 30 that has completed pre-lithiation treatment from the second fixing portion 202.

[0063] In some embodiments, the second fixing portion 202 is a second fixing protrusion 2021 protruding toward the bottom wall of the box body 100 ; or a second fixing groove 2022 recessed toward the bottom wall of the box body 100 .

[0064] For example, Figure 8 As shown, the second fixing portion 202 can be a second fixing protrusion 2021 protruding toward the bottom wall of the box body 100; when installing the reel 40 with the pole piece 30, the top end of the reel 40 can be sleeved on the surface of the first fixing protrusion 1011 to ensure that when the top cover 200 is covered on the box body 100, the second fixing protrusion 2021 at the bottom of the top cover 200 can limit the position of the reel 40 and improve the firmness of the reel 40 in the box body 100; it should be noted that, with regard to the second fixing protrusion 2021, the first fixing protrusion 1011 can be set to a raised columnar or ring shape, both of which can achieve the effect of limiting and fixing the reel 40.

[0065] For example, Figure 9 As shown, the second fixing portion 202 can be a second fixing groove 2022 that is recessed in the direction away from the bottom wall of the box body 100; when installing the reel 40 with the pole piece 30, the top end of the reel 40 can be inserted into the second fixing groove 2022 to ensure that when the top cover 200 is closed on the box body 100, the second fixing groove 2022 at the bottom of the top cover 200 can limit the position of the reel 40 and improve the firmness of the reel 40 in the box body 100; it should be noted that, as far as the second fixing groove 2022 is concerned, the second fixing groove 2022 can be set to a recessed columnar or annular shape, both of which can achieve the effect of limiting and fixing the reel 40.

[0066] It should be noted that the electrode 30 will be further explained in conjunction with the above-mentioned embodiment; when the electrode 30 is pre-lithiated, the electrode 30 needs to be placed inside a box 100 containing an electrolyte so that the electrolyte can fully infiltrate the electrode 30 and the lithium source 300, ensuring that a uniform and dense SEI film can be formed on the surface of the electrode 30; in order to improve the infiltration effect of the electrolyte, the layers of electrode 30 wound on the surface of the reel 40 can be arranged in a gap so that the electrolyte can flow into the gap to ensure that a continuous SEI film can be formed on the surface of the electrode 30; illustratively, when the electrode 30 is wound on the surface of the reel 40, a spacer can be set on the surface of the reel 40 (the spacer can be a raised structure formed by materials such as polypropylene, polyethylene, a composite diaphragm, a gel diaphragm, etc.) to form a gap between the layers of electrode 30 so that the electrolyte can fully infiltrate the surface of the electrode 30.

[0067] It should be noted that the electrode 30 will be further explained in conjunction with the above embodiment; for the pre-lithiation device 10, the lithium source 300 can be used as the positive electrode of the battery structure to provide lithium ions to the electrolyte, so it is necessary to ensure that the lithium source 300 is fully immersed in the electrolyte; since the reel 40 can separate the first placement area 110 from the second placement area 120, a through hole 41 can be opened on the curved side wall of the reel 40, so that the electrolyte can flow through the through hole 41, thereby improving the flatness of the liquid level surface and ensuring that the electrolyte can fully immerse the lithium source 300; in order to avoid contact between the electrode 30 and the lithium source 300, and to prevent the electrode 30 from blocking the through hole 41, the orthographic projection of the electrode 30 on the surface of the reel 40 does not coincide with the orthographic projection of the through hole 41 on the surface of the reel 40. For example, Figure 2 As shown, the through hole 41 can be provided at one end of the reel 40 close to the top cover 200 , which will not be described in detail here.

[0068] In some embodiments, the top cover 200 is provided with an exhaust component 203 , and an air inlet end of the exhaust component 203 is in communication with the interior of the box body 100 .

[0069] As for the pre-lithiation device 10, when the pre-lithiation device 10 is used to perform pre-lithiation treatment on the electrode 30, it is necessary to maintain a certain vacuum inside the box 100 to ensure the treatment effect on the electrode 30; Figure 1-Figure 4 as well as Figure 7-Figure 9 As shown, the top cover 200 is provided with an exhaust component 203, and the air inlet end of the exhaust component 203 is connected to the interior of the box body 100. The exhaust component 203 can be used to extract the gas generated during the pre-lithiation treatment of the electrode 30, thereby reducing the interference of the gas inside the box body 100 on the pre-lithiation process of the electrode 30, which is beneficial to improving the treatment effect and product quality of the electrode 30.

[0070] Exemplarily, the exhaust component 203 can be a vacuum pump with a conduit; when the top cover 200 is closed on the opening of the box body 100, the two ends of the conduit can be connected to the vacuum pump and the interior of the box body 100 respectively, so as to timely extract the gas generated during the pre-lithiation process of the electrode 30, which will not be repeated here.

[0071] In some embodiments, the top cover 200 is provided with a temperature sensor 204 for detecting the temperature inside the box body 100 , and / or is provided with a liquid level sensor 205 for detecting the electrolyte level inside the box body 100 .

[0072] As for the pre-lithiation device 10, when the electrode 30 is pre-lithiated using the pre-lithiation device 10, it is necessary to ensure that there is sufficient electrolyte inside the box 100 to ensure that the electrode 30 is immersed in the electrolyte after being placed inside the box 100; in order to improve the transfer ability of lithium ions in the electrolyte and improve the treatment effect on the electrode 30, it is also necessary to adjust the inside of the box 100 to a suitable temperature; wherein the temperature range in the box 100 can be a value between -20°C and 65°C; therefore, if Figure 1-Figure 4 as well as Figure 7-Figure 9 As shown, when the top cover 200 is provided with a temperature sensor 204 for detecting the internal temperature of the box body 100, the temperature inside the box body 100 can be monitored in real time so that the staff can adjust the temperature inside the box body 100 to an appropriate value; similarly, when the top cover 200 is provided with a liquid level sensor 205 for detecting the electrolyte level inside the box body 100, the temperature inside the box body 100 can be monitored in real time to ensure that the electrolyte inside the box body 100 can immerse the electrode 30, meet the pre-lithiation treatment requirements of the electrode 30, and when the electrolyte is insufficient, the electrolyte can be replenished in time according to the detection result of the liquid level sensor 205.

[0073] In some embodiments, the pre-lithiation device 10 also includes an electrolyte circulation component 400, which includes a first pipeline 410, a second pipeline 420, a liquid reservoir 430 and a pump body 440; the bottom wall of the box body 100 is provided with a liquid inlet port 103 and a liquid discharge port 104, and the first pipeline 410 and the second pipeline 420 are both provided with a shut-off valve 401, the first pipeline 410 is respectively connected to the liquid inlet port 103 and the liquid reservoir 430, and the second pipeline 420 is respectively connected to the liquid discharge port 104 and the liquid reservoir 430; the pump body 440 is arranged in the first pipeline 410.

[0074] Specifically, see Figure 10 ; Figure 10 This is a schematic diagram of the electrolyte circulation structure in this application.

[0075] As for the pre-lithiation device 10, when the electrode 30 is pre-lithiated, sufficient electrolyte needs to be added to the box 100 to meet the pre-lithiation treatment requirements of the electrode 30; therefore, an electrolyte circulation component 400 can be set in the pre-lithiation device 10 to enable it to continuously add electrolyte to the box 100 in the pre-lithiation device 10, and realize the recycling of the electrolyte, thereby reducing the cost of pre-lithiation.

[0076] Specifically, if Figure 1-Figure 4 as well as Figure 10 As shown, the electrolyte circulation component 400 may include a first pipeline 410, a second pipeline 420, a liquid reservoir 430 and a pump body 440; wherein, the bottom wall of the box body 100 is provided with a liquid inlet port 103 and a liquid discharge port 104, the electrolyte circulation component 400 can transport electrolyte to the inside of the box body 100 through the liquid inlet port 103, and recover the electrolyte in the box body 100 to the electrolyte circulation component 400 through the liquid discharge port 104; the first pipeline 410 and the second pipeline 420 are both provided with a stop valve 401, and the stop valve 401 can control the flow of the first pipeline 410 and the second pipeline 420 respectively. The on-off state can also adjust the flow rate passing through the two; the first pipeline 410 is connected to the liquid inlet port 103 and the liquid reservoir 430 respectively, and the second pipeline 420 is connected to the liquid discharge port 104 and the liquid reservoir 430 respectively, wherein the first pipeline 410 can be used as a liquid supply pipeline for the electrolyte, and the second pipeline 420 can be used as a liquid discharge pipeline for the electrolyte, which is conducive to the circulation and recovery of the electrolyte, and the liquid is stored in the liquid reservoir 430; in addition, the first pipeline 410 is provided with a pump body 440, which can provide driving force for the electrolyte to realize the circulation and transportation of the electrolyte.

[0077] like Figure 1 and Figure 2 As shown, when the electrode 30 is pre-lithiated using the pre-lithiation device, the electrolyte circulation component 400 can be used to replenish the electrolyte in the box 100, and the electrolyte circulation component 400 can also be used to recover the electrolyte in the box 100. Therefore, at different stages of pre-lithiation, the working state of the electrolyte circulation component 400 also has certain differences.

[0078] For example, when the electrolyte circulation assembly 400 is used to replenish the electrolyte into the box 100, the stop valve 401 of the first pipeline 410 can be controlled to open and the stop valve 401 of the second pipeline 420 can be closed, so that the electrolyte can be transported from the liquid reservoir 430 to the liquid inlet port 103 through the pump body 440 provided in the first pipeline 410, and then enter the box 100 through the liquid inlet port 103. When the electrolyte capacity in the box 100 meets the pre-lithiation treatment requirements and can immerse the lithium source 300 and the electrode 30, the stop valve 401 of the first pipeline 410 can be controlled to close so that there is sufficient electrolyte in the box 100.

[0079] For example, when the electrode 30 in the pre-lithiation device 10 is in a stationary state, the stop valves 401 of the first pipeline 410 and the second pipeline 420 can be closed, and the pump body 440 can also be stopped to ensure the stability of the electrolyte inside the box 100.

[0080] For example, when the electrode 30 is pre-lithiated using the pre-lithiation device 10, in one case, the stop valves 401 of the first pipeline 410 and the second pipeline 420 can be closed, and the pump body 440 can also be in a power-off state, so that the electrode 30 can be pre-lithiated in a relatively stable environment; in another case, the stop valves 401 of the first pipeline 410 and the second pipeline 420 can be opened, and the pump body 440 can also be in an operating state. At this time, the combination of the first pipeline 410, the second pipeline 420 and the liquid reservoir 430 can make the electrolyte in the box 100 circulate, alleviate the concentration difference of lithium ions in the electrolyte, and help improve the uniformity of the pre-lithiation treatment on the surface of the electrode 30.

[0081] For example, when the electrolyte in the box 100 is discharged using the electrolyte circulation component 400, the stop valve 401 set in the first pipeline 410 can be in a closed state, and the stop valve 401 set in the second pipeline 420 can be in an open state. At this time, the electrolyte in the box 100 can enter the second pipeline 420 from the discharge port 104 and flow back to the liquid reservoir 430 through the second pipeline 420, thereby realizing the recovery of the electrolyte.

[0082] In some embodiments, a first cavity 105 and a second cavity 106 are provided in the bottom wall of the box body 100, and at least a portion of the second cavity 106 surrounds the first cavity 105; multiple liquid inlet ports 103 and multiple liquid discharge ports 104 are provided, and the first cavity 105 is respectively connected to the first pipeline 410 and multiple liquid inlet ports 103, and the second cavity 106 is respectively connected to the second pipeline 420 and multiple liquid discharge ports 104.

[0083] As for the box body 100, the bottom wall inside the box body 100 is provided with a liquid inlet port 103 and a liquid discharge port 104. The liquid inlet port 103 is connected to the liquid reservoir 430 through a first pipe 410, and the liquid discharge port 104 is connected to the liquid reservoir 430 through a second pipe 420, thereby realizing the supply and discharge of the electrolyte inside the box body 100; Figure 1 、 Figure 2 、 Figure 4-Figure 6 as well as Figure 10 It can be seen that a first cavity 105 and a second cavity 106 can be provided in the bottom wall of the box body 100, and at least part of the second cavity 106 surrounds the first cavity 105, which is beneficial to controlling the thickness of the bottom wall of the box body 100; there are multiple liquid inlet ports 103 and liquid discharge ports 104, and they can be evenly arranged in a ring shape on the bottom wall of the box body 100, wherein the first cavity 105 is connected to the first pipeline 410 and the multiple liquid inlet ports 103 respectively, so that the electrolyte provided by the electrolyte circulation component 400 can enter the interior of the box body 100 through the multiple liquid inlet ports 103, thereby improving the electrolyte transportation efficiency and the uniformity of the electrolyte distribution; the second cavity 106 is connected to the second pipeline 420 and the multiple liquid discharge ports 104 respectively, which is beneficial to increasing the discharge speed of the electrolyte and preventing incomplete discharge of the electrolyte in the box body 100.

[0084] Specifically, when the electrolyte is transported to the box body 100 using the electrolyte circulation component 400, the electrolyte can be transported to the first cavity 105 through the first pipeline 410 so that the electrolyte fills the first cavity 105. Since the first cavity 105 is connected to the multiple liquid inlet ports 103, the electrolyte can enter the box body 100 through the multiple liquid inlet ports 103 at this time, thereby increasing the electrolyte replenishment speed; similarly, when the electrolyte in the box body 100 is discharged, the electrolyte in the box body 100 can enter the second cavity 106 through the multiple discharge ports 104, and then flow into the second pipeline 420 through the second cavity 106, so as to flow back to the liquid reservoir 430 through the second pipeline 420, thereby completing the recovery of the electrolyte.

[0085] In addition, after the pre-lithiation treatment of the electrode 30 is completed, the electrolyte is discharged from the box 100 through the electrolyte circulation device, and the roll 40 with the electrode 30 is taken out from the box 100; at this time, the rolled electrode 30 can be unfolded, and the electrolyte remaining on the surface of the electrode 30 can be dried using a drying oven, and then rewound; during the winding process, the surface morphology of the electrode 30 can be checked by CCD (Charge Coupled Device) visual inspection equipment to detect whether there are defects such as cracks or falling off on the surface of the electrode 30, so that the surface defects of the electrode 30 can be dealt with in time, which is beneficial to improving the product quality of the electrode 30.

[0086] It should be noted that the above description is limited to some embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in an order different from that described in the above embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0087] The various embodiments in this application are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0088] The description of this application is provided for purposes of illustration and description and is not intended to be exhaustive or to limit the application to the disclosed form. Many modifications and variations will be apparent to those skilled in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the application and to enable those skilled in the art to understand the application and design various embodiments with various modifications suitable for specific applications.

[0089] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present application (including the claims) is limited to these examples. Within the scope of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.

[0090] While the present application has been described in conjunction with specific embodiments thereof, many alternatives, modifications and variations of these embodiments will be apparent to those skilled in the art in light of the foregoing description.

[0091] The embodiments of the present application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of this application.

Claims

1. A pre-lithiation device for a pole piece, characterized in that: include: A box body, the box body comprising a first placement area and a second placement area; the second placement area is arranged around the first placement area, and the second placement area is configured to accommodate the electrode; A top cover, wherein the top of the box body is provided with an opening, and the top cover is adapted to the opening of the box body; a lithium source, the lithium source being located in the first placement area; The lithium source and the pole piece are arranged in a gap.

2. The pre-lithiation device for a pole piece according to claim 1, characterized in that: The pre-lithiation device processing device is connected to a power supply; when the electrode is subjected to pre-lithiation treatment, the lithium source is electrically connected to the positive electrode of the power supply, and the electrode is electrically connected to the negative electrode of the power supply.

3. The pre-lithiation device for a pole piece according to claim 2, characterized in that: A plurality of spring clips are provided at the bottom of the top cover, and the plurality of spring clips are electrically connected to the negative pole of the power supply; when the top cover is closed on the box body, the plurality of spring clips are located inside the box body, and at least some of the spring clips are clamped on the pole ears of the pole piece and electrically connected to the pole piece.

4. The pre-lithiation device for a pole piece according to claim 1, characterized in that: The bottom wall of the box body is provided with a first fixing portion, the first fixing portion is detachably connected to a reel, and the reel is provided with at least one layer of the pole piece around its circumference; The first fixing portion is a first fixing protrusion protruding toward the direction close to the top cover, or The first fixing groove is recessed in a direction away from the top cover.

5. The pre-lithiation device for a pole piece according to claim 4, characterized in that: The bottom wall of the box is provided with a lithium source installation portion, the lithium source installation portion is adapted to the lithium source, and a gap is arranged between the lithium source and the reel.

6. The pre-lithiation device for a pole piece according to claim 1, characterized in that: A second fixing portion is provided at the bottom of the top cover, and the second fixing portion is detachably connected to a reel, and the reel is provided with at least one layer of the pole piece around its circumference; The second fixing portion is a second fixing protrusion protruding toward the bottom wall of the box body; or The second fixing groove is recessed in a direction away from the bottom wall of the box body.

7. The pre-lithiation device for a pole piece according to claim 1, characterized in that: The top cover is provided with an exhaust component, and the air inlet end of the exhaust component is communicated with the interior of the box body.

8. The pre-lithiation device for a pole piece according to claim 1, characterized in that: The top cover is provided with a temperature sensor for detecting the temperature inside the box, and / or A liquid level sensor is provided for detecting the electrolyte level inside the box.

9. The pre-lithiation device for a pole piece according to claim 1, characterized in that: Also includes: An electrolyte circulation assembly, comprising a first pipeline, a second pipeline, a liquid reservoir, and a pump body; The bottom wall of the box body is provided with a liquid inlet port and a liquid discharge port, the first pipeline and the second pipeline are both provided with a shut-off valve, the first pipeline is connected with the liquid inlet port and the liquid reservoir respectively, and the second pipeline is connected with the liquid discharge port and the liquid reservoir respectively; the pump body is arranged in the first pipeline.

10. The electrode pre-lithiation device according to claim 9, characterized in that: A first cavity and a second cavity are provided in the bottom wall of the box body, and the second cavity at least partially surrounds the first cavity; there are multiple liquid inlet ports and multiple liquid discharge ports, the first cavity is connected to the first pipeline and the multiple liquid inlet ports respectively, and the second cavity is connected to the second pipeline and the multiple liquid discharge ports respectively.

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