Description:BACKGROUND
[0001]
The assembly of secondary cells such as Lithium-ion cells (hereinafter referred to as “cells”) include stacking or winding of a positive 5 electrode (cathode), a negative electrode (anode), and an electrolyte that enables ion transport between the electrodes. A separator is positioned between the electrodes to prevent electrical short circuits while permitting ionic conductivity. Further, the electrodes include some excess uncoated areas functioning as current collectors, called a tab, attached to it. Such tabs 10 are typically composed of a metallic conductor such as aluminum for the cathode or copper for the anode. Tabs are used for conducting current to and from the battery.
BRIEF DESCRIPTION OF FIGURES 15
[0002]
Systems and/or methods, in accordance with examples of the present subject matter are not described and with reference to the accompanying figures, in which:
[0003]
FIG. 1 illustrates a block diagram of a metallic debris removal system, in accordance with an example of the present subject matter; 20
[0004]
FIG. 2 illustrates a process flow diagram depicting removal of metallic debris from an electrode assembly, in accordance with an example of the present subject matter;
[0005]
FIG. 3 illustrates a method for removing metallic debris from an electrode assembly, in accordance with an example of the present subject 25 matter;
[0006]
FIG. 4 illustrates a comparative analysis of effectiveness of debris removal techniques by measuring the number of metallic particles measured across different samples S1 through S10 on an anode side of an electrode assembly, in accordance with an example of the present subject 30 matter; and 2
[0007]
FIG. 5 illustrates a comparative analysis of effectiveness of debris removal techniques by measuring the number of metallic particles measured across different samples S1 through S10 on a cathode side of an electrode assembly, in accordance with an example of the present subject matter. 5
[0008]
It may be noted that throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the 10 description; however, the description is not limited to the examples and/or implementations provided in the drawings.
DETAILED DESCRIPTION
[0009]
After manufacturing the electrode assembly, the tabs are 15 connected to current collectors or cell terminals through welding, soldering, or other mechanical connections. Typically, during assembly, the tabs are “crushed” or flattened to achieve a reduced height profile, enabling tighter packaging, and enhancing both thermal and electrical connection efficiency. The crushing of tabs involves application of compressive forces using 20 rollers, presses, or dies to flatten the tabs against the electrode assembly. However, the crushing leads to small pieces of metal, called debris, to break off from the tab. The debris may be understood as microscopic particles, or flakes that detach from a tab surface due to shear stress, surface abrasion, and a localized fracturing of the tab under high pressure. As may be evident, 25 the microscopic particles may not be visible to the eye but cause severe problems.
[0010]
For example, the introduction of debris inside the cell causes movement of metal pieces during charging or use of the cell. In an example, the debris may pierce through the separator layer, leading to a short circuit 30 within the cell. In severe conditions, the short circuit may give rise to cell 3
failure, or even thermal runaway causing the battery to overheat and catch fire.
[0011]
To address these concerns, conventional technologies often incorporate debris removal mechanisms after a tab crushing station. Commonly debris removal methods include vacuum suction systems that 5 may be configured to extract particles from the crushing station; compressed air nozzles for blowing debris away from the tab surface; rotating brushes to mechanically dislodge adhered debris; and sticky or adhesive rollers designed to capture and lift debris through surface contact.
[0012]
However, these conventional debris removal methods suffer from 10 several limitations. One of the major challenges in removing the debris stems from the accumulation of electrostatic charges during the tab crushing process. As the tab materials are subjected to friction and mechanical deformation against metallic or non-conductive surfaces, static electricity is generated. The static electricity causes the detached metallic 15 particles to become electrostatically attracted to nearby surfaces, including the tab. Once adhered through static forces, the debris are difficult to remove using conventional technologies. For example, vacuum and air-blow systems often fail to capture finer particles, particularly those that become embedded in a surface of the tab or lodged within the 20 microstructures created during crushing.
[0013]
Moreover, mechanical cleaning components, such as brushes or rollers, rely on physical contact to remove debris from the surface. However, such components may wear down over time due to continuous use and friction. As a result, the mechanical components may require frequent 25 maintenance or replacement to remain effective. Additionally, the friction and contact involved in mechanical cleaning may cause the components to shed tiny particles, known as secondary particles. These particles may add to the overall contamination, rather than eliminating it. Furthermore, the 4
conventional methods are not always capable of reaching areas between tightly compressed layers or within folds and crevices of the tab geometry.
[0014]
Example approaches for removing metallic debris from an electrode assembly are described. The present subject matter relates to approaches for removing metallic debris from an electrode assembly by 5 neutralizing a static charge present on the electrode assembly leading to accumulation of metallic debris onto the axial end surfaces of the electrode assembly due to the compression of tabs.
[0015]
For example, a system for removing metallic debris from an electrode assembly includes a chamber, one or more ionizing units, and a 10 removing unit. The system may be used after a tab flattening process to remove metallic debris resulting during the flattening of a cylindrical jelly roll. In an example, a method for removing metallic debris from an electrode assembly may include conveying the electrode assembly through the chamber for a pre-defined time. In an example, the electrode assembly 15 includes compressed tabs and metallic debris accumulated onto axial end surfaces due to presence of static charges. The method may further include directing one or more ion beams onto the axial end surfaces of the electrode assembly to neutralize the static charge and consequently removing the metallic debris from the electrode assembly upon neutralizing the static 20 charges.
[0016]
The metallic debris removal system and method of the present subject matter offers several advantages over existing approaches by neutralizing static charges on electrode assembly by performing ionization. In this manner, the effectiveness of debris removal is enhanced. By 25 neutralizing the static charges, the ionizing unit eliminates electrostatic adherence between the electrode assembly and the debris, thereby allowing the subsequent air flow to effectively dislodge the loosened debris. Moreover, the non-contact nature of the debris removing method helps preserve the integrity of the electrode assembly, thereby enhancing 30 5
cleaning efficiency. Therefore, the present subject matter helps mitigate the risk of short circuits and thermal runaway events caused by metallic debris bridging the anode and cathode.
[0017]
The above aspects are further described in conjunction with the figures, and in the associated description below. It should be noted that the 5 description and figures merely illustrate principles of the present subject matter. Therefore, various assemblies that encompass the principles of the present subject matter, although not explicitly described or shown herein, may be devised from the description, and are included within its scope.
[0018]
FIG. 1 illustrates a block diagram of a metallic debris removal 10 system 100, in accordance with an example of the present subject matter. The metallic debris removal system 100 (hereinafter referred to as the “system” 100). The system 100 may include a chamber 102, one or more ionizing units 104, a removing unit 106, and one or more ports 108. The chamber 102 may form the main enclosure of the various components of 15 the system 100. The chamber 102 may include a rigid outer shell constructed from materials, such as stainless steel, aluminum, reinforced polymers or the like. The chamber 102 may provide a controlled environment for the debris removal process, isolating an electrode assembly from external contaminants and containing any removed debris. 20
[0019]
Further, the chamber 102 may be configured to accommodate a conveyor path along which electrode assemblies may be transported for sequential processing. The chamber 102 may include one or more openings to allow entry and exit of the conveyor path. These openings may be equipped with flexible seals, air curtains, or other containment features to 25 maintain internal environmental conditions. Further, one or more ionizing units 104 and the removing unit 106 may be positioned sequentially within the chamber 102 along a direction of the conveyor path. Such a sequential arrangement enables the stepwise treatment of the electrode assemblies, including neutralization of static charges and removal of debris. 30 6
[0020]
In an example, the chamber 102 may have a longitudinal configuration with openings at opposing ends to allow linear movement of the conveyor path. Alternatively, the chamber 102 may have a circular or closed-loop configuration to facilitate continuous circulation of the electrode assemblies within the chamber 102. 5
[0021]
Further, the ionizing unit 104 may be configured to generate and emit one or more ion beams directed onto a surface of the electrode assembly to neutralize static charges that may cause debris to adhere. The ion beams produced by the ionizing unit 104 may contain both positively and negatively charged ions. Accordingly, the ionizing unit 104 may facilitate 10 effective neutralization regardless of the polarity of the surface charge present on the electrode assembly.
[0022]
In an example, effectiveness of the system 100 for metallic debris removal from electrode assemblies was evaluated across different ionizer air pressures. As depicted in Table 1 below, experiments were conducted 15 at 0.05 MPa, 0.25 MPa, and 0.5 MPa to assess the impact on debris removal efficiency. The results were analyzed separately for cathode and anode surfaces. Sample 0.05 MPa 0.25 MPa 0.5 MPa Cathode Anode Cathode Anode Cathode Anode
S1
56
23
25
9
12
5
S2
35
32
22
6
20
7
S3
39
16
33
12
17
4
S4
27
14
19
15
13
8
S5
32
28
17
8
14
10
Table 1
[0023]
As is evident from Table 1 above, for both cathode and anode 20 surfaces, a clear trend emerged showing improved debris removal as air 7
pressure increased. At a relatively low air pressure of approximately 0.05 MPa, particle counts were consistently higher, with cathode samples showing between 27-56 particles and anode samples showing 14-32 particles. When the ionizer air pressure increased to approximately 0.25 MPa, a significant reduction in particle counts was observed, with cathode 5 samples dropping to 17-33 particles and anode samples to 6-15 particles. The most effective debris removal occurred at 0.5 MPa, where cathode samples showed only 12-20 particles and anode samples showed 4-10 particles.
[0024]
These results demonstrate a strong correlation between increased 10 ionizer air pressure and enhanced effectiveness in dislodging and removing debris from electrode surfaces. The 0.5 MPa setting proved most effective, likely due to enhanced ion delivery and spread across the electrode surfaces. This optimal pressure may provide sufficient force to dislodge debris while maintaining effective charge neutralization. The experiments 15 were conducted with a consistent ionization time of 2 seconds, suggesting that this duration is sufficient for effective treatment when combined with the optimal air pressure of 0.5 MPa.
[0025]
Further, impact of ionization time on metallic debris removal from electrode assemblies was investigated through a series of experiments. As 20 depicted in Table 2 below, three different ionization durations - 2 seconds, 4 seconds, and 6 seconds - were tested while maintaining a constant air pressure of 0.5 MPa. The effectiveness of debris removal was evaluated separately for cathode and anode surfaces across multiple samples. Sample 2 sec Ionizing 4 sec Ionizing 6 sec Ionizing Cathode Anode Cathode Anode Cathode Anode
S1
19
14
21
9
16
10
S2
6
7
25
11
9
4 8
S3
17
10
22
10
28
7
S4
8
1
28
6
15
9
S5
16
8
19
7
29
18
Table 2
[0026]
The results showed varying particle counts across the different ionization times . For cathode surfaces, the 2-second ionization time resulted in particle counts ranging from 6 to 19, the 4-second time showed counts between 19 and 28, and the 6-second time yielded counts from 9 to 5 29. Anode surfaces displayed generally lower particle counts, with ranges of 1-14 for 2 seconds, 6-11 for 4 seconds, and 4-18 for 6 seconds of ionization. Notably, the effectiveness of debris removal appeared quite similar for both the 2-second and 6-second durations.
[0027]
Given the comparable performance between the shortest and 10 longest ionization times, the 2-second duration was determined to be the most practical choice. This decision takes into account the speed requirements of the conveying line for tab flattening and aims to minimize the impact on overall production output. On performing ionization for prolonged time, secondary particles will be generated due to high energy of 15 the ion beams emitting from the ionizer. This may be seen from the data in Table 2, i.e., on increasing the ionization time, residual particle count is increasing. Therefore, by selecting the shortest effective ionization time, the process may maintain efficiency while still achieving satisfactory debris removal results. This optimization balances the need for thorough cleaning 20 with the demands of high-volume manufacturing in battery production.
[0028]
Referring back to FIG.1, the removing unit 106 may be located within the chamber 102, typically positioned downstream of the ionizing unit 104 along the direction of the conveyor path.
[0029]
The removing unit 106 may be responsible for physically removing 25 the metallic debris that have been loosened or dislodged from the electrode 9
assembly surface as a result of prior neutralization of static charges by the ionizing unit 104. In an example, the removing unit 106 may include a high-pressure air nozzle system configured to deliver targeted air jets across the surface of the electrode assembly. These air jets generate a mechanical force sufficient to sweep away the loosened particles without damaging the 5 underlying electrode material. In another example, the removing unit 106 may incorporate a vacuum suction mechanism, either alone or in combination with air blowing, to dislodge and collect the loosened debris.
[0030]
In another example, the ionizing unit 104 and the removing unit 106 may be integrated together. In this case, the removing unit 106 may be 10 configured to operate at various air pressures to accommodate different types of electrode assembly materials or debris compositions. In some examples, the system 100 may include a mechanism to adjust the air pressure delivered to the removing unit 104, enabling pressure settings within a range of about 0.3 Megapascal (MPa) to about 0.7 MPa. This 15 adjustable pressure mechanism may allow the system 100 to be fine-tuned based on sensitivity of the electrode material or the nature of debris. In an example, directing the one or more ion beams with a pressure of approximately 0.3 MPa to 0.5 MPa may produce effective results in dislodging and removing metallic debris that tends to cling to the electrode 20 surfaces due to residual static charge.
[0031]
In some examples, the system 100 may incorporate sensors and feedback mechanisms to dynamically adjust the debris removal process. In some cases, real-time monitoring of particle counts, or static charge levels may be used to automatically adjust ionization intensity, air pressure, or 25 conveyor speed to optimize the debris removal efficiency for each individual electrode assembly.
[0032]
Further, the chamber 102 may include one or more ports 108. The ports 108 may be fitted with specialized seals or gaskets to maintain the internal environment of the chamber 102. Further, the ports 108 may be 30 10
used for discarding the metallic debris from the chamber. The operations of the aforementioned units are described with respect to FIG. 2.
[0033]
The metallic debris removal system neutralizes the static charges present on the surface of the electrode assembly, thereby neutralizing the electrostatic adherence between the debris and the surface of the electrode 5 assembly. In this way, the loosened debris is effectively removed from the surface of the electrode assembly.
[0034]
FIG. 2 illustrates a process flow diagram 200 depicting removal of metallic debris from an electrode assembly (not shown), in accordance with an example of the present subject matter. Specifically, the diagram 200 10 depicts the progression of the electrode assembly from its initial state with protruding tabs to the final state after debris removal.
[0035]
In an initial state, an electrode assembly 202 is depicted. The electrode assembly 202 comprises multiple layers of electrode materials, including cathodes, anodes, and separators. These layers are stacked or 15 wound together to form a core of a battery. During the manufacturing process, the electrode materials are cut and arranged such that portions of the conductive current collector foils extend beyond the active material coatings at predetermined intervals. These extending portions of the current collector foils form the upper tabs 204-1 and lower tabs 204-2. In an 20 example, the upper tabs 204-1 and lower tabs 204-2 (collectively referred to as tabs 204) may protrude from axial end surfaces 206 of the electrode assembly 202 for creating connection points for the positive and negative terminals of the battery.
[0036]
Once assembled, the electrode assembly 202 may undergo a 25 compression or flattening process. The compression process may involve several techniques used for compressing or crushing the protruding tabs of the electrode assembly. Such techniques may be known in the art and therefore have not been discussed here in detail. For example, mechanical pressure may be applied using rollers or presses to compress the tabs 30 11
against the axial end surfaces of the electrode assembly. During the compression process, the tabs 204 may be compressed or “flattened” against the axial end surfaces 206 of the electrode assembly 202. In an example, the compressed tabs may lie flush with the axial end surfaces 206 of the electrode assembly 202. 5
[0037]
As discussed above, during this process, metallic debris may accumulate onto the axial end surfaces 206 of the electrode assembly 202. Further, the rapid movement and sudden contact between the rollers and the electrode assembly may exacerbate the generation of static charges through triboelectric effects. In some cases, the sudden release of pressure 10 after compression may cause a rapid redistribution of charges, potentially leading to localized areas of high charge density on the compressed tab 204 and adjacent surfaces of the electrode assembly 202.
[0038]
Following the compression process, the electrode assembly 202 may be received in a chamber 208 via a conveyor path 210. In an example, 15 the chamber 208 may be similar to the chamber 102. The chamber design may be adapted to accommodate different production line configurations. In some cases, a modular chamber design may be implemented, allowing for easy integration into existing manufacturing processes. The chamber 208 may also feature adjustable dimensions to accommodate various electrode 20 assembly sizes and shapes.
[0039]
The conveyor path 210 may be used to transport the electrode assembly 202 through the chamber 208. The conveyor path 210 may move the electrode assembly 202 at a controlled speed, allowing for precise timing of the ionization and debris removal processes. 25
[0040]
Within the chamber 208, one or more ionizing units 212 may be positioned to direct ion beams onto the axial end surfaces 206 of the electrode assembly 202. The ionizing units 212 may comprise one or more devices designed to generate and emit ions for neutralizing static charges on the axial end surfaces 206 of the electrode assembly 202. The ionizing 30 12
units 212 may employ various ionization techniques known in the state of the art for generating ion beams. For example, the ionizing units 212 may utilize corona discharge technology, bipolar ionization technology, radioactive ionization sources, pulsed Direct current (DC) technology, or the like to generate and direct ion beams onto the electrode assembly 202. 5
[0041]
In some examples, the ionizing units 212 may be arranged in various configurations within the chamber 208. In some cases, the ionizing units 212 may be positioned around the periphery of the chamber 208. In another example, the ionizing units 212 may be placed orthogonal to the axial end surfaces 206 of the electrode assembly 202. Accordingly, the one 10 or more ion beams may be directed orthogonally on the axial end surfaces 206 of the electrode assembly 202.
[0042]
The ionizing units 212 may be configured to generate both positively and negatively charged ion beams. During operation, the ions directed towards the axial end surfaces 206 of the electrode assembly 202 15 are attracted to oppositely charged metallic debris accumulated onto the axial end surfaces 206 of the electrode assembly 202. When an ion encounters a static charge, the ion may transfer its charge, thereby neutralizing the static electricity. The neutralization process may occur rapidly, with ions combining with static charges almost instantaneously upon 20 contact. The quick neutralization can disrupt the electrostatic forces holding metallic debris to the surfaces of the electrode assembly.
[0043]
In some implementations, the ionization process creates a cloud of charged particles around the electrode assembly. This ion cloud may help to equalize the electric potential across the surface, reducing localized 25 areas of high charge density that could attract and hold debris. Further, the constant flux of charged particles may dislodge the metallic debris particles from the axial end surfaces 206 of the electrode assembly 202.
[0044]
Upon neutralizing the static charges, the electrode assembly may be introduced to a removing unit such as the removing unit 214. The 30 13
removing unit 214 may be integrated into the ionizing unit 212. In an example, the removing unit 214 may enable upon neutralization of static charges. The removing unit may remove the metallic debris from the electrode assembly 202 that is already neutralized. In an example, the removing unit 214 may utilize high-pressure air blowing techniques in which 5 compressed air is directed at the electrode assembly 202 through precision nozzles. The air pressure may be adjusted to provide sufficient force for debris removal without damaging the delicate electrode structures. The high-pressure air stream may create localized turbulence near the axial end surfaces of the electrode assembly 202. The turbulence may help dislodge 10 particles that have been neutralized but remain loosely adhered to the electrode assembly 202. In another example, the removing unit 214 may incorporate vacuum suction systems in certain aspects. These systems may create a negative pressure zone near the surface of the electrode assembly 202, actively pulling neutralized debris away from the surface. The vacuum 15 suction may be particularly effective for collecting smaller particles that might otherwise become airborne. The direction of air flow generated by air blowing is represented by the arrow A.
[0045]
In some examples, the removing unit 214 may combine both air blowing and vacuum suction in a coordinated manner. The air blowing may 20 dislodge and mobilize the debris, while simultaneous vacuum suction captures and removes the particles, as indicated by arrow B, preventing redeposition on other areas of the electrode assembly 202. Additionally, the removing unit 214 may utilize electrostatic attraction methods to capture and remove charged particles that may remain after the ionization process. 25
[0046]
The removing unit 214 may be designed with adjustable parameters to optimize debris removal for different electrode assembly configurations. Factors such as air pressure, vacuum strength, nozzle orientation, and treatment duration may be fine-tuned based on the specific characteristics of the electrode materials and the nature of the debris. The 30 14
removing unit 214 may be equipped with specialized nozzles or attachments designed to access hard-to-reach areas of the electrode assembly 202, such as the edges of the compressed tab 204 or internal layers of wound electrodes. These targeted cleaning tools may ensure comprehensive debris removal from all surfaces. 5
[0047]
In some examples, the removing unit 214 may operate in a controlled atmosphere within the chamber 208. This controlled environment may help maintain the cleanliness of the air used for blowing and prevent the introduction of new contaminants during the debris removal process. Upon removal of the metallic debris from the surface of the electrode 10 assembly 202, the metallic debris may be discarded from the chamber 208 via one or more ports (not shown in the figure) provided in the chamber.
[0048]
The aforementioned approaches for metallic debris removal offers significant advantages. For example, the combination of ionizing and air flow techniques provide a comprehensive approach to metallic debris 15 removal. The use of ion beams to neutralize static charges on electrode assembly surfaces enhances the effectiveness of subsequent debris removal, thereby resulting in thorough cleaning. Moreover, by containing debris within a confined space, the system may reduce the risk of contamination to surrounding areas or other manufacturing processes. By 20 effectively removing metallic debris and neutralizing static charges, the system may help mitigate various risks associated with the presence of conductive particles in battery cells, such as internal short-circuits, minimizing the potential for thermal runaway events, and preserving the intended electrochemical performance of the battery. 25
[0049]
FIG. 3 illustrates a method for removing metallic debris from an electrode assembly, in accordance with an example of the present subject matter. The method 300 is described in the context of a metallic debris removal system which is similar to the aforementioned system 100. 15
[0050]
In an example, at block 302, the method 300 may include directing one or more ion beams onto one or more axial end surfaces of the electrode assembly during compression of the tabs to neutralize static charges. For example, block 302 may be performed during the compression to limit the accumulation of metallic debris onto the electrode assembly during 5 compression of tabs. In one example, one or more ionizing units may be positioned along a conveyor path transporting the electrode assembly for compressing the tabs.
[0051]
The one or more ionizing beams may generate and direct the ion beams onto the axial end surfaces of the electrode assembly during 10 compression or flattening of the tabs. The compression process may involve several techniques used for compressing or crushing the protruding tabs of the electrode assembly. As discussed, the axial end surfaces accumulate a high amount of metallic debris during compression. Further, compression may also increase the generation of static charges onto the axial end 15 surfaces of the electrode assembly.
[0052]
Therefore, directing the one or more ion beams onto the one or more axial end surfaces of the electrode assembly during compression of the tabs may neutralize the charges generated due to compression, therefore restricting the accumulation of metallic debris onto the electrode 20 assembly. For example, the directing one or more ion beams may include directing both positively and negatively charged ion beams onto the electrode assembly, and specifically the axial end surfaces of the electrode assembly. The ions directed towards the axial end surfaces may attract oppositely charged metallic debris accumulated onto the axial end surfaces 25 of the electrode assembly. When an ion encounters a static charge, it may transfer its charge, thereby neutralizing the static electricity. The neutralization process may occur rapidly, with ions combining with static charges almost instantaneously upon contact. The quick neutralization can disrupt the electrostatic forces holding metallic debris to the surfaces of the 30 16
electrode assembly. Therefore, the accumulation of metallic debris may be prevented.
[0053]
At block 304, the method 300 may include conveying the electrode assembly through a chamber for a pre-defined time. For example, the pre-defined time period for conveying the electrode assembly through the 5 chamber may be about 2-4 seconds for achieving optimal results. In an example, the electrode assembly may include compressed tabs and metallic debris accumulated onto the axial end surfaces due to the presence of static charges.
[0054]
For example, the electrode assembly may be transported through 10 the chamber with the help of a conveyor path. As may be noted, the use of a conveyor path for conveying the electrode assembly though the chamber is merely exemplary and other known technologies may be used for conveying the electrode assembly through the chamber.
[0055]
In an example, after directing the one or more ion beams onto the 15 electrode assembly, some metallic debris may still persist onto the surface of the electrode assembly.
[0056]
For example, the electrode assembly, including compressed tabs and metallic debris accumulated onto the axial end surfaces due to the presence of static charges, may be conveyed through a chamber for a pre-20 defined time. The conveying of the electrode assembly through the chamber may include moving the electrode assembly at a controlled speed allowing for precise removal of metallic debris.
[0057]
At block 306, the method 300 may include directing one or more ion beams onto the axial end surfaces of the electrode assembly to 25 neutralize the static charges. In an example, block 306 may be implemented similar to block 302, therefore the details have not been described again to maintain brevity. 17
[0058]
As discussed above, directing the one or more ion beams onto the axial end surfaces of the electrode assembly may neutralize the static charges and the constant flux of charged particles may dislodge the metallic debris particles from the axial end surfaces of the electrode assembly.
[0059]
Further, at block 308, high-pressure air may blow onto the axial 5 end surfaces of the electrode assembly to remove the metallic debris. For example, blowing high-pressure air onto the electrode assembly may include directing compressed air through precision nozzles at an adjustable pressure to provide sufficient force for debris removal without damaging the delicate electrode structures. 10
[0060]
Due to the high turbulence, the metallic debris that has already been neutralized but remains loosely adhered to the electrode assembly may dislodge from the electrode assembly.
[0061]
Furthermore, at block 310, the method 300 may include inducing vacuum in the chamber to remove the metallic debris. In an example, in 15 addition to blowing high pressure air, the method 300 may also include inducing vacuum into the chamber to create a negative pressure zone near the surface of the electrode assembly, actively pulling neutralized metallic debris away from the surface.
[0062]
In some examples, block 308 and block 310 may be combined in 20 a coordinated manner to achieve precise results.
[0063]
The aforementioned method for removing metallic debris from the electrode assembly prevents accumulation of the metallic debris during and after compression ensuring precise removal of metallic debris. Specifically, ionizing during compression may neutralize the charges as they form, 25 reducing the overall amount of metallic debris that adheres to the electrode surface, improving the efficiency of removing the metallic debris. Moreover, the combination of air blowing and vacuum induction may provide a thorough cleaning action by actively dislodging and extracting the loosened debris, preventing the redeposition of the metallic debris onto the electrode 30 assembly. 18
[0064]
In an example, a Millipore test may be conducted onto the electrode assembly to analyze the effectiveness of debris removal. The test may include filtering a solution that has been in contact with the electrode assembly and counting the particles captured on the filter. FIG. 4 and FIG.5 illustrate graph 400 and graph 500, respectively, depicting the performance 5 analysis and experimental results of the impact of the debris removal process on metallic debris counts obtained through the Millipore test in accordance with an example of the present subject matter.
[0065]
For example, FIG. 4 depicts a comparative analysis of effectiveness of debris removal techniques by measuring the number of 10 metallic particles measured across different samples S1 through S10 on an anode side of an electrode assembly (not shown). The x-axis of the graph 400 represents the sample numbers (S1 through S10), while the y-axis represents the number of particles detected. The graph 400 displays a first data curve 402 representing the count of metallic debris remaining onto the 15 surface of the electrode assembly after removing the debris using conventional techniques without employing ionization and removal of particles. Further, the graph 400 depicts a second data curve 404 indicating the counts of metallic debris onto the surface of the electrode assembly after removing the debris using the system 100. 20
[0066]
As may be seen, the first data curve 402 shows higher metallic debris count ranging from approximately 20 to 60 particles across the sample range. Whereas the second data curve 404 exhibits consistently lower particle counts, ranging between approximately 5 to 20 particles across all samples. The reduction in the count of metallic debris may 25 indicate the effectiveness of the approaches for metallic debris removal in removing metallic debris from the electrode assembly.
[0067]
In another example, FIG. 5 depicts a comparative analysis of effectiveness of debris removal techniques by measuring the number of metallic particles measured across different samples S1 through S10 on a 30 cathode side of an electrode assembly (not shown). The x-axis of the graph 19
500 represents the sample numbers (S1 through S10), while the y-axis represents the number of particles detected. The graph 500 displays a first data curve 502 representing the count of metallic debris remaining onto the surface of the electrode assembly after removing the debris using conventional techniques. Further, the graph 500 depicts a second data 5 curve 504 indicating the counts of metallic debris onto the surface of the electrode assembly after removing the debris using the system 100.
[0068]
As may be noted, the first data curve 502 shows higher overall metallic debris count, peaking at approximately 55 particles for sample S2 before stabilizing between 30-40 particles for subsequent samples. The first 10 data curve overall ranges from approximately 20 to 60 particles across the sample range whereas, the second data curve 504 maintains consistently lower particle counts, ranging between approximately 5 to 25 particles across all samples.
[0069]
The reduction in the count of metallic debris may indicate the 15 effectiveness of the approaches for metallic debris removal in removing metallic debris from the electrode assembly.
[0070]
Accordingly, the consistent lower values of the second data curve 404 and the second data curve 504 across multiple samples indicates the reproducibility and reliability of the debris removal process. 20
[0071]
Although aspects and other examples have been described in a language specific to structural features and/or methods, the present subject matter is not necessarily limited to such specific features or elements as described. Rather, the specific features are disclosed as examples and should not be construed to limit the scope of the present subject matter. 25
20
I/We Claim:
1. A method (300) for removing metallic debris from an electrode assembly (202), the method (300) comprising:
conveying (304) the electrode assembly through a chamber (102, 208) for a pre-defined time, wherein the electrode assembly includes 5 compressed tabs (204) and metallic debris accumulated onto axial end surfaces (206) due to presence of static charges;
directing (306) one or more ion beams onto the axial end surfaces (206) of the electrode assembly, wherein the one or more ion beams neutralize the static charges; and 10
upon neutralizing the static charges, removing the metallic debris from the electrode assembly.
2. The method (300) as claimed in claim 1, wherein prior to conveying the electrode assembly, the method comprises:
directing (302) the one or more ion beams onto the axial end surfaces 15 (206) of the electrode assembly during compression of the tabs (204), to neutralize the static charges.
3. The method (300) as claimed in claim 1, wherein the one or more ion beams include positively and negatively charged ions.
4. The method (300) as claimed in claim 3, wherein the one or more ion 20 beams are directed orthogonally on the axial end surfaces (206) of the electrode assembly.
5. The method (300) as claimed in claim 1, wherein the pre-defined time period for conveying the electrode assembly through the chamber (102, 208) comprises about 2 to 4 seconds. 25
6. The method (300) as claimed in claim 1, wherein directing the one or more ion beams onto the electrode assembly comprises directing the one or more ion beams with a pressure of approximately 0.3 to 0.5 MPa. 21
7. The method (300) as claimed in claim 1, wherein removing the debris comprises blowing (308) high-pressure air onto the axial end surfaces (206) to remove the metallic debris.
8. The method (300) as claimed in claim 7, wherein the method further comprises inducing (310) vacuum in the chamber (102, 208) to remove the 5 metallic debris from the electrode assembly.
9. A system (100) for removing metallic debris from an electrode assembly (202), the system (100) comprising:
a chamber (102, 208) for receiving the electrode assembly (202) along a conveyor path (210) for a pre-defined time, wherein the electrode 10 assembly (202) includes compressed tabs (204) and metallic debris accumulated onto the axial end surfaces (206) due to presence of static charges;
one or more ionizing units (104, 212) for directing one or more ion beams onto the axial end surfaces (206) of the electrode assembly (202), 15 wherein the one or more ion beams neutralize the static charges; and
a removing unit (106, 214) for removing the metallic debris from the electrode assembly (202), upon neutralizing the static charges.
10. The system (100) as claimed in claim 9, wherein the one or more ionizing units (104, 212) are to direct the one or more ion beams onto the 20 axial end surfaces (206) of the electrode assembly (202) during compression of the tabs (204), to neutralize the static charges prior to the conveying of the electrode assembly (202).
11. The system (100) as claimed in claim 9, wherein the chamber (102, 208) comprises one or more ports (108) to discard the debris upon 25 removal of the debris from the electrode assembly (202).
12. The system (100) as claimed in claim 9, wherein the one or more ion beams include positively and/or negatively charged ions. 22
13. The system (100) as claimed in claim 9, wherein the one or more ionizing units (104, 212) are to direct the one or more ion beams orthogonally on the axial end surfaces (206) of the electrode assembly (202).
14. The system (100) as claimed in claim 9, wherein the pre-defined time 5 period for conveying the electrode assembly (202) through the chamber (102, 208) comprises about 2 to 4 seconds .
15. The system (100) as claimed in claim 9, wherein the removing unit (106, 214) is to blow high-pressure air onto the axial end surfaces (206) to remove the metallic debris. 10
16. The system (100) as claimed in claim 9, wherein the removing unit (106, 214) is to induce vacuum in the chamber (102, 208) to remove the metallic debris from the electrode assembly (202).
17. The system (100) as claimed in claim 9, wherein the ionizing units (104, 212) are to direct the one or more ion beams onto the electrode 15 assembly (202) with a pressure of approximately 0.3 to 0.5 MPa.
23
ABSTRACT
DEBRIS REMOVAL FOR ELECTRODE ASSEMBLY
The present subject matter discloses approaches for removing 5 metallic debris from an electrode assembly (202). For example, a method (300) for removing metallic debris includes conveying the electrode assembly through a chamber (102, 208) for a pre-defined time, wherein the electrode assembly (202) includes compressed tabs (204) and metallic debris accumulated onto the axial end surfaces (206) due to presence of 10 static charges. One or more ion beams are directed onto the axial end surfaces (206) of the electrode assembly to neutralize the static charges. Upon neutralizing the static charges, the metallic debris is removed from the electrode assembly (202).
15
To be published with Fig. 2
24 , Claims:I/We Claim:
1. A method (300) for removing metallic debris from an electrode assembly (202), the method (300) comprising:
conveying (304) the electrode assembly through a chamber (102, 208) for a pre-defined time, wherein the electrode assembly includes 5 compressed tabs (204) and metallic debris accumulated onto axial end surfaces (206) due to presence of static charges;
directing (306) one or more ion beams onto the axial end surfaces (206) of the electrode assembly, wherein the one or more ion beams neutralize the static charges; and 10
upon neutralizing the static charges, removing the metallic debris from the electrode assembly.
2. The method (300) as claimed in claim 1, wherein prior to conveying the electrode assembly, the method comprises:
directing (302) the one or more ion beams onto the axial end surfaces 15 (206) of the electrode assembly during compression of the tabs (204), to neutralize the static charges.
3. The method (300) as claimed in claim 1, wherein the one or more ion beams include positively and negatively charged ions.
4. The method (300) as claimed in claim 3, wherein the one or more ion 20 beams are directed orthogonally on the axial end surfaces (206) of the electrode assembly.
5. The method (300) as claimed in claim 1, wherein the pre-defined time period for conveying the electrode assembly through the chamber (102, 208) comprises about 2 to 4 seconds. 25
6. The method (300) as claimed in claim 1, wherein directing the one or more ion beams onto the electrode assembly comprises directing the one or more ion beams with a pressure of approximately 0.3 to 0.5 MPa. 21
7. The method (300) as claimed in claim 1, wherein removing the debris comprises blowing (308) high-pressure air onto the axial end surfaces (206) to remove the metallic debris.
8. The method (300) as claimed in claim 7, wherein the method further comprises inducing (310) vacuum in the chamber (102, 208) to remove the 5 metallic debris from the electrode assembly.
9. A system (100) for removing metallic debris from an electrode assembly (202), the system (100) comprising:
a chamber (102, 208) for receiving the electrode assembly (202) along a conveyor path (210) for a pre-defined time, wherein the electrode 10 assembly (202) includes compressed tabs (204) and metallic debris accumulated onto the axial end surfaces (206) due to presence of static charges;
one or more ionizing units (104, 212) for directing one or more ion beams onto the axial end surfaces (206) of the electrode assembly (202), 15 wherein the one or more ion beams neutralize the static charges; and
a removing unit (106, 214) for removing the metallic debris from the electrode assembly (202), upon neutralizing the static charges.
10. The system (100) as claimed in claim 9, wherein the one or more ionizing units (104, 212) are to direct the one or more ion beams onto the 20 axial end surfaces (206) of the electrode assembly (202) during compression of the tabs (204), to neutralize the static charges prior to the conveying of the electrode assembly (202).
11. The system (100) as claimed in claim 9, wherein the chamber (102, 208) comprises one or more ports (108) to discard the debris upon 25 removal of the debris from the electrode assembly (202).
12. The system (100) as claimed in claim 9, wherein the one or more ion beams include positively and/or negatively charged ions. 22
13. The system (100) as claimed in claim 9, wherein the one or more ionizing units (104, 212) are to direct the one or more ion beams orthogonally on the axial end surfaces (206) of the electrode assembly (202).
14. The system (100) as claimed in claim 9, wherein the pre-defined time 5 period for conveying the electrode assembly (202) through the chamber (102, 208) comprises about 2 to 4 seconds .
15. The system (100) as claimed in claim 9, wherein the removing unit (106, 214) is to blow high-pressure air onto the axial end surfaces (206) to remove the metallic debris. 10
16. The system (100) as claimed in claim 9, wherein the removing unit (106, 214) is to induce vacuum in the chamber (102, 208) to remove the metallic debris from the electrode assembly (202).
17. The system (100) as claimed in claim 9, wherein the ionizing units (104, 212) are to direct the one or more ion beams onto the electrode 15 assembly (202) with a pressure of approximately 0.3 to 0.5 MPa.