Pretreatment sagger and sintering equipment
By setting a lithium layer at the bottom of the sagger and optimizing the sagger design during the sintering process of lithium-ion battery cathode materials, the problem of abnormal lithium content in lithium-ion battery cathode materials was solved, achieving an efficient and stable sintering process and improving product quality and production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GEM WUXI ENERGY MATERIAL CO LTD
- Filing Date
- 2025-03-26
- Publication Date
- 2026-05-05
AI Technical Summary
Abnormal lithium content in lithium-ion battery cathode materials during sintering leads to a decline in the physicochemical properties and electrochemical performance of the finished product. Existing lithium replenishment methods are costly and have unstable effects, affecting production efficiency and product quality.
A lithium layer is set at the bottom of the sagger body, using lithium carbonate, lithium hydroxide or lithium oxide material, combined with a grid-like groove structure and sealing groove design to prevent lithium absorption and volatilization, and to prevent oxidation through a gas circulation system, along with precise temperature control and sagger support design.
It improves lithium utilization and sintering efficiency, reduces production costs, extends crucible life, ensures product quality and consistency, and reduces energy consumption and exhaust emissions.
Smart Images
Figure CN224202204U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of lithium battery cathode material technology, specifically to a pretreatment crucible and sintering equipment. Background Technology
[0002] In the manufacturing of lithium-ion battery cathode materials, the sagger is a crucial tool in the sintering process, used to support and heat the cathode material. However, the cycle life of the sagger is limited, especially during product switching or line opening, and the extensive use of brand-new saggers can cause several problems. The porous structure of a brand-new sagger absorbs lithium during sintering, leading to insufficient lithium content in the cathode material. This, in turn, affects the physicochemical and electrochemical properties of the finished product, such as reduced capacity and shortened cycle life. Furthermore, the surface and interior of a brand-new sagger contain numerous micropores. These pores adsorb lithium ions from the cathode material during high-temperature sintering, resulting in lithium loss. Under high-temperature conditions, lithium may react chemically with the sagger material to form stable compounds, further exacerbating lithium loss. In such cases, lithium replenishment is necessary.
[0003] In related technologies, lithium carbonate is usually used for lithium replenishment. Lithium carbonate is expensive, and the lithium replenishment process requires precise control, which increases production costs. The lithium replenishment operation requires additional process steps, which prolongs the production cycle and affects production efficiency. After lithium replenishment, lithium ions may not be able to fully recover to normal levels, and the lithium replenishment process may introduce new impurities or defects, affecting material performance. Utility Model Content
[0004] In view of this, the present invention provides a pretreatment crucible and sintering equipment to solve the problem of abnormal lithium content during the sintering process of cathode materials.
[0005] In a first aspect, this utility model provides a pretreatment sagger, comprising:
[0006] The body of the sagger;
[0007] A lithium layer is placed at the bottom of the sagger body to prevent lithium from being absorbed by the sagger body during sintering.
[0008] The lithium layer is composed of one of the following materials: lithium carbonate, lithium hydroxide, or lithium oxide, and is fixed to the bottom of the crucible body.
[0009] Beneficial Effects: The lithium layer, located at the bottom of the sagger body, effectively prevents lithium absorption by the sagger body during sintering, thereby reducing lithium loss and maximizing lithium utilization. Because the lithium layer prevents lithium absorption by the sagger, the chemical reactions during sintering are more stable, contributing to improved sintering efficiency and reduced energy consumption. The lithium layer can be composed of lithium carbonate, lithium hydroxide, or lithium oxide, allowing for the selection of the most suitable material based on specific process requirements, thus optimizing the sintering process. The lithium layer, fixed at the bottom of the sagger body, simplifies the production process, reduces additional operating steps, and lowers production costs. By preventing lithium loss, the lithium content of the final product is more stable, contributing to improved product quality and consistency. The presence of the lithium layer reduces direct contact between the sagger body and lithium, thereby reducing sagger corrosion and wear, and extending the sagger's service life.
[0010] In one alternative embodiment, the bottom of the sagger body is provided with a groove structure, which is distributed in a grid pattern.
[0011] Beneficial effects: The grid-like groove structure enhances the adhesion of the lithium layer, increasing the contact area between the bottom of the sagger and the lithium layer. This better secures the lithium layer, preventing it from detaching or shifting during sintering and ensuring its stability. The grid structure also helps the lithium layer material distribute evenly within the grooves, avoiding localized accumulation or gaps, thus ensuring uniform lithium release during sintering and improving product quality consistency. Furthermore, the grid-like groove structure increases the surface area of the sagger bottom, facilitating uniform heat conduction and preventing localized overheating or uneven heat distribution, thereby improving sintering efficiency.
[0012] In one alternative embodiment, a sealing groove is provided on the top edge of the sagger body, and a sealing ring is embedded in the sealing groove.
[0013] Beneficial effects: The combination of the sealing groove and sealing ring effectively prevents the leakage or entry of gases or impurities during sintering, ensuring the airtightness of the sagger interior and maintaining a stable sintering environment. Lithium is prone to volatilization during high-temperature sintering. The sealing structure effectively reduces lithium volatilization loss, improves lithium utilization, and lowers production costs. The sealing structure also prevents external impurities from entering the sagger interior, avoiding contamination of the sintered materials and thus improving the purity and quality of the sintered product.
[0014] In one alternative embodiment, the exterior of the sagger body is coated with an antioxidant coating.
[0015] Beneficial effects: Extends the service life of the sagger. The anti-oxidation coating effectively prevents the sagger from reacting with oxygen at high temperatures, reducing oxidation and corrosion, thereby extending the sagger's service life. By preventing oxidation, the coating can reduce the wear and tear on the sagger material, lower the replacement frequency, and save production costs.
[0016] In one alternative embodiment, ribs are provided on the side wall of the sagger body.
[0017] Beneficial effects: Ribs can significantly improve the mechanical strength of the sidewalls of the sagger, making it less prone to deformation or cracking under high temperature, high pressure or mechanical impact, thereby improving the durability of the sagger.
[0018] Secondly, this utility model also provides a sintering apparatus for processing the aforementioned pretreated saggers, comprising:
[0019] A sintering furnace, which includes a heating device and a temperature control system;
[0020] The sagger support frame is set inside the sintering furnace to fix and arrange multiple pre-treated saggers. The ribs are connected to the sagger support frame.
[0021] A gas circulation system is used to introduce inert or reducing gases into the furnace during the sintering process to prevent lithium oxidation.
[0022] Beneficial Effects: The temperature control system precisely regulates the temperature within the sintering furnace, ensuring the sintering process operates within the optimal temperature range, thus improving product quality and consistency. The sagger support frame secures and arranges multiple pre-treated saggers, ensuring their stability during sintering and preventing material loss or contamination due to movement or tipping. By rationally arranging the saggers, the space within the sintering furnace is maximized, increasing the yield per sintering cycle. The sagger support frame connects with the ribs on the sagger sidewalls, enhancing sagger stability and preventing displacement or tilting during sintering. The support frame design facilitates sagger loading and unloading, simplifying operations and improving production efficiency. By introducing inert gases (such as nitrogen or argon) or reducing gases (such as hydrogen) into the furnace, the gas circulation system effectively prevents lithium from oxidizing at high temperatures due to reaction with oxygen, reducing lithium loss. Recycling the gas reduces waste emissions and environmental impact. The coordinated operation of the heating device, temperature control system, sagger support frame, and gas circulation system enables a highly efficient and stable sintering process, significantly improving production efficiency. The fit and connection between the sagger support and the ribs, along with the protective function of the gas circulation system, reduces equipment wear and extends its service life. By reducing lithium oxidation loss, lowering energy consumption, and minimizing emissions, the overall design offers significant environmental benefits.
[0023] In one alternative embodiment, the sagger support frame is provided with a positioning groove that matches the bottom shape of the pre-treated sagger, and the edge of the positioning groove is provided with a groove suitable for engaging with the rib.
[0024] Beneficial effects: The sagger support frame is equipped with positioning grooves, and the edges of these grooves have recesses to engage with the ribs of the pre-treated sagger. The positioning grooves match the shape of the sagger's bottom, ensuring precise positioning of the sagger on the support frame and preventing displacement or tilting during sintering. Precise positioning reduces uneven sintering and material loss caused by inaccurate sagger placement, improving product quality. The positioning groove and recess design ensure a tight connection between the sagger and the support frame, preventing movement due to vibration or gas flow during sintering. The interlocking structure between the ribs and recesses enhances the sagger's stability, preventing it from tipping over at high temperatures or during handling, reducing material waste and equipment damage.
[0025] In one alternative embodiment, the gas circulation system includes a gas supply device and an exhaust device, the gas supply device being adapted to regulate the gas flow rate and pressure.
[0026] Beneficial effects: By adjusting the gas flow rate, the concentration and distribution of gas inside the furnace can be precisely controlled, ensuring the stability of the gas environment during sintering.
[0027] In one alternative embodiment, the sintering equipment further includes a detection device for monitoring the integrity and thickness of the lithium layer at the bottom of the pretreated crucible.
[0028] Beneficial effects: The detection device can monitor the integrity of the lithium layer in real time, avoiding uneven sintering or lithium loss caused by damage or missing lithium layers, thereby improving the quality of sintered products.
[0029] In one alternative embodiment, the detection device further includes an observation window suitable for observing the sintering process.
[0030] Beneficial effects: The observation window is suitable for manual observation of the internal sintering environment, so as to facilitate the observation of the working process at any time and prevent errors.
[0031] Since the sintering equipment includes a pretreatment sagger, which has the same effect as the pretreatment sagger, it will not be elaborated here. Attached Figure Description
[0032] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0033] Figure 1 This is a schematic diagram of the pretreatment sagger of this utility model;
[0034] Figure 2This is a schematic diagram of the pre-treated crucible before the lithium layer is assembled.
[0035] Explanation of reference numerals in the attached figures:
[0036] 1. Sagger body; 2. Lithium layer; 3. Sealing groove; 4. Ribs; 5. Groove structure. Detailed Implementation
[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0038] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0039] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0040] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.
[0041] In the manufacturing of lithium-ion battery cathode materials, the sagger, as a key tool in the sintering process, supports and heats the cathode material, ensuring it completes chemical reactions and structural formation at high temperatures. The performance of the sagger directly affects the quality, consistency, and production efficiency of the cathode material. However, the cycle life of the sagger is limited, especially during product switching or line opening, and the extensive use of brand-new saggers can lead to a series of problems. The porous structure of a brand-new sagger absorbs lithium during sintering, resulting in insufficient lithium content in the cathode material, which in turn affects the physicochemical properties and electrochemical performance of the finished product, such as reduced capacity and shortened cycle life. Specifically, a brand-new sagger has numerous micropores on its surface and inside. These pores adsorb lithium ions from the cathode material during high-temperature sintering, leading to lithium loss. Furthermore, at high temperatures, lithium may react chemically with the sagger material to form stable compounds, further exacerbating lithium loss. This lithium loss not only affects the chemical composition of the cathode material but may also lead to structural defects, thereby reducing its electrochemical performance.
[0042] To compensate for lithium loss, lithium replenishment is commonly used in related technologies, with lithium carbonate being the most frequently employed replenishing agent. However, lithium carbonate is expensive, and the replenishment process requires precise control, increasing production costs. Lithium replenishment typically involves several steps: first, accurately measuring the amount of lithium lost from the cathode material; second, calculating the required amount of lithium carbonate to add based on the loss; and finally, uniformly mixing the lithium carbonate into the cathode material and performing a secondary sintering process to ensure uniform lithium distribution. This process not only increases complexity but also prolongs the production cycle, impacting efficiency. Furthermore, the effectiveness of lithium replenishment is not always ideal; lithium ions may not fully recover after replenishment, and the process may introduce new impurities or defects, affecting material performance. For example, lithium carbonate may not decompose completely at high temperatures, resulting in residual impurities; or uneven lithium distribution during replenishment may lead to localized performance differences in the material. These issues not only increase production costs but may also negatively impact the quality and consistency of the final product.
[0043] The following is combined Figures 1 to 2 The following describes embodiments of the present invention.
[0044] According to an embodiment of the present invention, a pre-treatment sagger is provided, comprising: a sagger body 1; a lithium layer 2, wherein the lithium layer 2 is disposed at the bottom of the sagger body 1 and is adapted to prevent lithium from being absorbed by the sagger body 1 during sintering; the lithium layer 2 is composed of one of lithium carbonate, lithium hydroxide or lithium oxide and is fixed at the bottom of the sagger body 1.
[0045] A lithium layer 2 is disposed at the bottom of the sagger body 1, effectively preventing lithium from being absorbed by the sagger body 1 during sintering, thereby reducing lithium loss and ensuring maximum lithium utilization. Because the lithium layer 2 prevents lithium absorption by the sagger, the chemical reaction during sintering is more stable, contributing to improved sintering efficiency and reduced energy consumption. The lithium layer 2 can be composed of lithium carbonate, lithium hydroxide, or lithium oxide, allowing for the selection of the most suitable material based on specific process requirements, thus optimizing the sintering process. The lithium layer 2, fixed to the bottom of the sagger body 1, simplifies the production process, reduces additional operating steps, and lowers production costs. By preventing lithium loss, the lithium content of the final product is more stable, contributing to improved product quality and consistency. The presence of the lithium layer 2 reduces direct contact between the sagger body 1 and lithium, thereby reducing sagger corrosion and wear, and extending the sagger's service life. Specifically, lithium can be evenly applied to the bottom of the sagger body 1 by brushing.
[0046] In some embodiments, combined with Figure 1 As shown, the bottom of the sagger body 1 is provided with a groove structure 5, which is distributed in a grid pattern.
[0047] The grid-like groove structure 5 enhances the adhesion of the lithium layer 2, increasing the contact area between the bottom of the sagger and the lithium layer 2. This better secures the lithium layer 2, preventing it from detaching or shifting during sintering and ensuring its stability. The grid structure also helps the lithium layer 2 material distribute evenly within the grooves, avoiding localized accumulation or gaps, thus ensuring uniform lithium release during sintering and improving product quality consistency. Furthermore, the grid-like groove structure 5 increases the surface area of the sagger bottom, facilitating uniform heat conduction and preventing localized overheating or uneven heat distribution, thereby improving sintering efficiency.
[0048] Furthermore, a sealing groove 3 is provided on the top edge of the sagger body 1, and a sealing ring is embedded in the sealing groove 3. The combination of the sealing groove 3 and the sealing ring can effectively prevent the leakage or entry of gas or impurities during sintering, ensuring the airtightness of the sagger interior and thus maintaining a stable sintering environment. During high-temperature sintering, lithium is prone to volatilization. The sealing structure can effectively reduce lithium volatilization loss, improve lithium utilization, and reduce production costs. The sealing structure can prevent external impurities from entering the sagger interior, avoiding contamination of the sintering material, thereby improving the purity and quality of the sintered product.
[0049] Furthermore, the outer surface of the sagger body 1 is coated with an anti-oxidation coating. This coating effectively prevents the sagger from reacting with oxygen at high temperatures, reducing oxidation and corrosion, thus extending its service life. By preventing oxidation, the coating reduces material loss in the sagger, lowers replacement frequency, and saves production costs.
[0050] Furthermore, the side wall of the sagger body 1 is provided with ribs 4. The ribs 4 can significantly improve the mechanical strength of the side wall of the sagger, making it less prone to deformation or cracking under high temperature, high pressure or mechanical impact, thereby improving the durability of the sagger.
[0051] According to an embodiment of the present invention, another aspect provides a sintering apparatus, comprising: a sintering furnace for processing the aforementioned pretreated saggers, including: a sintering furnace, the sintering furnace including a heating device and a temperature control system; a sagger support frame, the sagger support frame being disposed inside the sintering furnace for fixing and arranging a plurality of the pretreated saggers, the ribs 4 being connected in cooperation with the sagger support frame; and a gas circulation system, the gas circulation system being used to introduce inert gas or reducing gas into the furnace during the sintering process to prevent lithium oxidation.
[0052] The temperature control system precisely regulates the temperature within the sintering furnace, ensuring the sintering process operates within the optimal temperature range, thus improving product quality and consistency. The sagger support frame secures and arranges multiple pre-treated saggers, ensuring their stability during sintering and preventing material loss or contamination due to movement or tipping. By rationally arranging the saggers, the space within the sintering furnace is maximized, increasing the yield per sintering cycle. The sagger support frame connects with the ribs 4 on the sagger sidewalls, enhancing sagger stability and preventing displacement or tilting during sintering. The support frame design facilitates sagger loading and unloading, simplifying operations and improving production efficiency. By introducing inert gases (such as nitrogen or argon) or reducing gases (such as hydrogen) into the furnace, the gas circulation system effectively prevents lithium from oxidizing at high temperatures due to reaction with oxygen, reducing lithium loss. Recycling the gas reduces waste emissions and environmental impact. The coordinated operation of the heating device, temperature control system, sagger support frame, and gas circulation system enables a highly efficient and stable sintering process, significantly improving production efficiency. The fit between the sagger support and rib 4, along with the protective function of the gas circulation system, reduces equipment wear and extends its service life. By reducing lithium oxidation loss, lowering energy consumption, and minimizing emissions, the overall design offers significant environmental benefits.
[0053] Furthermore, the sagger support frame is equipped with a positioning groove that matches the bottom shape of the pre-treated sagger. The positioning groove has a recessed edge for engaging with the rib 4. The positioning groove on the sagger support frame, with its recessed edge for engaging with the rib 4 of the pre-treated sagger, ensures precise positioning of the sagger on the support frame, preventing displacement or tilting during sintering. Precise positioning reduces uneven sintering or material loss caused by inaccurate sagger positioning, improving product quality. The positioning groove and recessed edge design ensure a tight connection between the sagger and the support frame, preventing movement of the sagger due to vibration or gas flow during sintering. The engaging structure between the rib 4 and the recessed edge enhances the stability of the sagger, preventing it from tipping over at high temperatures or during handling, reducing material waste and equipment damage.
[0054] Furthermore, the gas circulation system includes a gas supply device and an exhaust device, the gas supply device being adapted to regulate gas flow and pressure. By regulating the gas flow, the concentration and distribution of gas within the furnace can be precisely controlled, ensuring the stability of the gas environment during sintering.
[0055] In some embodiments, the sintering equipment further includes a detection device for monitoring the integrity and thickness of the lithium layer 2 at the bottom of the pretreatment sagger. The detection device can monitor the integrity of the lithium layer 2 in real time, avoiding uneven sintering or lithium loss due to damage or absence of the lithium layer 2, thereby improving the quality of the sintered product.
[0056] In some embodiments, the detection device further includes an observation window suitable for observing the sintering process. The observation window is suitable for manual observation of the internal sintering environment, so as to facilitate continuous monitoring of the work progress and prevent errors.
[0057] Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and all such modifications and variations fall within the scope defined by the present invention.
Claims
1. A pretreatment sagger, characterized in that, include: Sagger body (1); A lithium layer (2) is disposed at the bottom of the sagger body (1) to prevent lithium from being absorbed by the sagger body (1) during sintering. The lithium layer (2) is composed of one of lithium carbonate, lithium hydroxide or lithium oxide and is fixed to the bottom of the sagger body (1); The bottom of the sagger body (1) is provided with a groove structure (5), which is distributed in a grid pattern.
2. The pretreatment sagger according to claim 1, characterized in that, The top edge of the sagger body (1) is provided with a sealing groove (3), and a sealing ring is embedded in the sealing groove (3).
3. The pretreatment crucible according to claim 1, characterized in that, The outer surface of the sagger body (1) is coated with an anti-oxidation coating.
4. The pretreatment sagger according to claim 1, characterized in that, The side wall of the sagger body (1) is provided with ribs (4).
5. A sintering apparatus for processing the pretreated saggers according to any one of claims 1 to 4, characterized in that, include: A sintering furnace, the sintering furnace including a heating device and a temperature control system; A sagger support frame is provided inside the sintering furnace for fixing and arranging multiple pre-treated saggers. The sagger body (1) is connected to the sagger support frame. A gas circulation system is provided for introducing inert or reducing gases into the furnace during the sintering process to prevent lithium oxidation.
6. The sintering equipment according to claim 5, characterized in that, The sagger support frame is provided with a positioning groove, which matches the bottom shape of the pre-treated sagger. The edge of the positioning groove is provided with a groove, which is suitable for engaging with the sagger body (1).
7. The sintering equipment according to claim 5, characterized in that, The gas circulation system includes a gas supply device and an exhaust device, wherein the gas supply device is adapted to regulate the gas flow rate and pressure.
8. The sintering equipment according to claim 5, characterized in that, The sintering equipment also includes a detection device for monitoring the integrity and thickness of the lithium layer (2) at the bottom of the pretreated sagger.
9. The sintering equipment according to claim 8, characterized in that, The detection device also includes an observation window, suitable for observing the sintering process.