A lithium ion battery lithium precipitation inhibition process based on dynamic current modulation

Abstract

The application discloses a lithium ion battery lithium precipitation inhibition process based on dynamic current modulation and relates to the technical field of lithium ion batteries, and comprises the following steps: step 1, dividing the ridge and the two side regions of the pole piece into a ridge partition and two adjacent partitions and connecting the partitions by a bidirectional transfer branch; and step 2, after the first input section ends, obtaining a ridge reference section position, a contact unloading front section position and an electric quantity migration front section position, determining a rebound migration misregistration zone between the two fronts, and determining the front and rear partitions according to the migration direction. The application determines the rebound migration misregistration zone by obtaining the ridge reference section position, the contact unloading front section position and the electric quantity migration front section position corresponding to the ridge of the pole piece, determines the area where the local contact state rollback is out of synchronization with the electric quantity cross-zone migration as the rebound migration misregistration zone, and adjusts the main input, low-amplitude unloading and tail quantity receiving relationship of the ridge partition and the two adjacent partitions on the basis of the actual migration direction of the tail quantity in the zone.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery technology, and in particular to a lithium-ion battery lithium plating suppression process based on dynamic current modulation. Background Technology

[0002] With the widespread application of lithium-ion batteries in power equipment, energy storage devices, and mobile terminals, battery charging speed, cycle life, and safety have received increasing attention. During charging, lithium-ion batteries release lithium ions from the positive electrode and migrate towards the negative electrode, subsequently embedding them into the negative electrode active material. When the charging current is high, the ambient temperature is low, the negative electrode's lithium embedding capacity decreases, or the battery's internal state is uneven, the migration and embedding rate of lithium ions may be lower than the input current rate. Some lithium ions will deposit as metallic lithium on the negative electrode surface, forming lithium plating. The continuous accumulation of deposited metallic lithium not only causes loss of active lithium and battery capacity decay but may also form lithium dendrites and increase the risk of internal short circuits.

[0003] Existing technologies typically mitigate the risk of lithium plating through two main approaches: material improvement and charging control. Regarding materials, improvements can be made to lithium-ion transport conditions and the negative electrode interface state by modifying the anode material, adjusting the electrolyte composition, coating the separator, and reducing electrode surface roughness. In terms of charging control, measures such as low-temperature current reduction, staged charging, and limiting the charging ceiling can be implemented based on battery temperature, voltage, or state of charge to reduce the battery's exposure to continuously high charging currents under adverse conditions. While these methods can reduce the probability of lithium plating to some extent, they usually target the entire battery cell or pre-defined charging stages.

[0004] However, during coating, rolling, assembly, and recycling, electrodes may still experience localized protrusions, inconsistent compaction, uneven interface contact, or varying degrees of aging, leading to differences in current distribution and charge transfer states across different regions of the electrode. When the charging current changes or the internal state of the battery alters, some localized areas may continue to receive a large current input, while charge transfer in adjacent areas may not be fully completed. Existing methods of overall current reduction or staged charging struggle to adjust the current load relationship according to the actual state of different regions of the electrode. A uniform reduction in charging current can negatively impact overall charging efficiency; conversely, maintaining a high charging current may exacerbate localized current concentration and lithium plating. Therefore, a lithium-ion battery lithium plating suppression process based on dynamic current modulation is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a lithium-ion battery lithium plating suppression process based on dynamic current modulation to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a lithium-ion battery lithium plating suppression process based on dynamic current modulation, comprising the following steps: Step 1: Divide the ridge and two sides of the electrode into a ridge zone and two adjacent zones, and connect them with bidirectional transfer branches; Step 2: After the first input segment ends, obtain the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment. Determine the area between the two leading edges as the rebound migration misalignment zone, determine the front and rear partitions according to the migration direction, and determine the partition equalization charge within the misalignment zone as the tail quantity within the zone. Step 3: When the next input segment enters, the preceding partition is determined as the main input partition and receives the main input current, the ridge partition is determined as the unloading partition and outputs a low-amplitude unloading current through the bidirectional transfer branch, and the following partition is determined as the tail quantity receiving partition and receives the unloading current and the in-band tail quantity. Step 4: When the leading edge of the power migration crosses the boundary of the adjacent partition, the main input partition, unloading partition, and tail quantity receiving partition are rotated along the direction of movement; Step 5: When the new misalignment band intersects with the previous misalignment band, merge the tail quantities of the two misalignment bands and the bands in the same direction and continue to rotate; when the two bands separate, unload the load area by area from the rear end of the previous misalignment band and restore the common input. Step 6: When the new misalignment band is in the opposite direction to the previous misalignment band, the tail quantity in the original band cancels out the reverse tail quantity, and the subsequent rotation direction is determined according to the remaining direction; after the misalignment band is closed, the corresponding partitions jointly receive the remaining input segments.

[0007] Preferably, the process of restoring the ridge partition from the unloaded partition to the common input partition includes: When the in-band tail quantity is transferred to the rear partition and the leading edge of the power migration crosses the ridge reference segment, the ridge partition is determined as a candidate recovery partition. A portion of the main input current is transferred from the front partition to the candidate recovery partition, while the front partition continues to receive the remaining main input current, and the rear partition continues to receive the in-band tail quantity, forming a recovery trial section. Within the recovery test section, when the leading edge of the power migration continues to move away from the convex ridge reference section along the original migration direction, and the leading edge of the contact unloading does not retreat towards the convex ridge reference section, the candidate recovery partition participates in the common input. When the leading edge of the power migration re-enters the range corresponding to the convex ridge reference segment, or when the leading edge of the contact unloading retreats to the convex ridge reference segment, the candidate recovery state of the candidate recovery partition is cancelled, the convex ridge partition is restored to output a low-amplitude unloading current to the rear partition, and the partition balanced power formed in the recovery test section is incorporated into the in-band tail quantity.

[0008] Preferably, the rotation process of the main input partition, unloading partition, and tail quantity receiving partition includes: When the leading edge of the power migration crosses the boundary of the adjacent partition, the next partition in the migration direction is determined as the candidate receiving partition, and the current main input partition, unloading partition and tail quantity receiving partition are maintained in their active states. The in-band tail quantity received by the current tail quantity receiving partition is transferred to the candidate receiving partition via a bidirectional transfer branch, and the newly formed partition equalization power during the transfer is continuously incorporated into the in-band tail quantity. After the in-band tail quantity is transferred, the current tail quantity receiving partition is converted into the main input partition, the current main input partition is converted into the unloading partition, and the candidate receiving partition is converted into the new tail quantity receiving partition. Before the in-band tail quantity completes the transfer, when the leading edge of the power migration returns to the adjacent partition boundary it has crossed, the candidate acceptance state of the candidate acceptance partition is cancelled, the transferred in-band tail quantity is sent back to the original tail quantity acceptance partition, and the original partition function state is maintained.

[0009] Preferably, the processing procedure when the new misalignment zone intersects with the previous misalignment zone includes: The overlapping partition of the two misaligned bands is identified as the cross-band transition partition, and the unloaded state of the cross-band transition partition is maintained. The in-band tail of the previous misaligned band enters the crossband transition zone along the original migration direction, and the crossband transition zone is restricted from participating in the main input current of any misaligned band. After the tail quantity within the band of the previous misaligned band enters the non-overlapping partition of the new misaligned band through the cross-band transfer partition, it is merged into the tail quantity within the same band of the new misaligned band, and the non-overlapping partition is determined as the tail quantity receiving partition of the new misaligned band. Before the tail quantity within the previous misaligned band completes the cross-band transfer, when the two misaligned bands change from intersecting to separating, the cross-band transfer stops, the tail quantity within the band that has entered the cross-band transfer partition is returned to the original tail quantity receiving partition of the previous misaligned band, and the two misaligned bands resume partition rotation respectively.

[0010] Preferably, the processing procedure when the new misalignment band is in the opposite direction to the previous misalignment band includes: The reverse tail quantity formed by the new misalignment band is introduced into the bidirectional transfer branch, forming a counteracting segment with the tail quantity in the original band of the previous misalignment band, and maintaining the function state of the main input partition, unloading partition and tail quantity receiving partition corresponding to the previous misalignment band before the counteracting is completed. When the reverse tail amount is less than the original tail amount, the remaining original tail amount after cancellation is retained in the original tail amount receiving partition, maintaining the original partition rotation direction, and restricting the new misaligned band from starting reverse rotation. When the reverse tail quantity is equal to the original tail quantity, the original tail quantity and the reverse tail quantity cancel each other out, and the opposing cancellation segment ends, maintaining the current partitioning state until the charge migration front crosses the adjacent partition boundary corresponding to the new misalignment band. When the reverse tail quantity is greater than the original tail quantity, the excess portion is determined as the reverse residual tail quantity and transferred to the partition behind the new misalignment band; after the reverse residual tail quantity is transferred and the previous misalignment band is closed, the rotation direction of the main input partition, the unloading partition and the tail quantity receiving partition is reversed.

[0011] Preferably, the process of obtaining the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment includes: Obtain the surface height sequence of the electrode along the ridge partition and the arrangement direction of two adjacent partitions, determine the interval that is continuously higher than the adjacent positions on both sides as the ridge interval, and determine the partition position corresponding to the ridge interval as the ridge reference segment; After the first input segment ends, according to the thickness reduction order of the ridge partition and the two adjacent partitions, the boundary between the partition that has continuously completed the thickness reduction along the reduction direction and the partition that has not yet completed the thickness reduction is determined as the contact unloading front edge segment. Obtain the partition equalization current between adjacent partitions, accumulate the migrated power in each partition according to the flow direction of the partition equalization current, and determine the partition boundary where the power transfer across partitions is finally completed along the migration direction as the leading edge segment of power migration.

[0012] Preferably, the process of unloading the two misaligned bands in a zone-by-zone manner after separation includes: Starting from the end of the previous misalignment zone, the judgment is performed zone by zone according to the order in which each zone is removed from the previous misalignment zone. When a certain partition is completely removed from the previous misalignment band and the new misalignment band, and the in-band tail quantity in that partition has been transferred to the adjacent partition, the low-amplitude unloading current output by that partition is released, and that partition participates in the common input. If the current partition has not yet escaped any misalignment zone, or if the in-band tail quantity within the partition has not yet been transferred, suspend the release of the partition and its subsequent partitions. When the first two misaligned bands intersect again after the area-by-area removal is completed, the subsequent removal is stopped, so that the unremoved sections continue to be unloaded, and the sections that have been removed but have re-entered the misaligned band resume outputting a low-amplitude unloading current, and the sections are incorporated into the re-merged misaligned band.

[0013] Preferably, the process for determining the closure of the springback migration misalignment zone includes: When the contact unloading leading edge segment coincides with the charge migration leading edge segment, it is determined whether there is any in-band tail quantity in the rebound migration misalignment band that has not yet completed cross-regional transfer. When the two leading edge segments overlap and there is no in-band tail quantity that has not yet completed cross-regional transfer, the rebound migration misalignment zone is determined to be closed. When two leading edge segments overlap, but there are still in-band tail quantities that have not yet completed cross-regional transfer, the transfer direction of the current tail quantity receiving zone and bidirectional transfer branch is maintained until the in-band tail quantity completes cross-regional transfer, and then the rebound migration misalignment zone is closed. When the two leading edge segments of the in-band tail quantity separate again before the cross-regional transfer is completed, the rebound migration misalignment zone is re-determined based on the two leading edge segments after the re-separation, and the in-band tail quantity that has not yet completed the cross-regional transfer is incorporated into the re-determined rebound migration misalignment zone.

[0014] Preferably, the process of transferring the in-band tail quantity across bands via the crossband transfer zone includes: Establish connectivity between the original tail quantity receiving partition of the previous misalignment zone and the cross-band transfer partition, as well as connectivity between the cross-band transfer partition and the non-overlapping partition of the new misalignment zone, to form a directional continuation path along the original migration direction. After all the tail quantities within the band leave the original tail quantity receiving partition, the connection between the original tail quantity receiving partition and the cross-band transfer partition is disconnected, while the connection between the cross-band transfer partition and the non-overlapping partition is maintained until all the tail quantities within the band enter the non-overlapping partition. Before all the tail quantities in the band enter the non-overlapping partition, when the two misaligned bands change from intersecting to separating, the reverse guide is opened to the directional continuation path, and the tail quantities in the band that have entered the non-overlapping partition and the cross-band transfer partition are returned to the original tail quantity receiving partition in sequence. After the cross-band transfer or return is completed, the connection formed between the previous misaligned band and the new misaligned band through the cross-band transfer partition is disconnected, and the bidirectional transfer branches within each misaligned band are restored.

[0015] Preferably, the rotation of the partition's operational state is carried out zone by zone according to the arrangement order of each partition along the direction of electrical energy migration; The in-band tail quantity is transferred only between adjacent partitions via bidirectional transfer branches. When the in-band tail quantity in the current tail quantity receiving partition has not yet been transferred out, the next partition in the migration direction is not allowed to participate in the subsequent rotation. After the in-band tail quantity completes its transfer to the adjacent partition, the adjacent partition that received the in-band tail quantity is used as the tail quantity receiving partition for subsequent rotation.

[0016] The technical effects and advantages of this invention are as follows: 1. This invention obtains the reference segment of the ridge, the contact unloading front segment, and the charge migration front segment corresponding to the electrode ridge. It identifies the area where the local contact state declines and the charge migration across zones is asynchronous as a rebound migration misalignment zone. Based on the actual migration direction of the tail quantity within the zone, it adjusts the main input, low-amplitude unloading, and tail quantity receiving relationships of the ridge zone and its adjacent zones. This reduces the amount of main input current concentrated in the ridge zone before the local charge has migrated out, allowing adjacent zones to take over the low-amplitude unloading current and the tail quantity within the zone, thus shifting the adjustment focus from the entire cell to a local area of ​​the electrode. Compared to existing overall current reduction or preset charging stage control methods, this invention balances the suppression of local lithium plating risk with normal current input in other areas, reducing charging efficiency loss caused by uniformly reducing charging current, and solving the problem of existing technologies that struggle to adjust current receiving relationships according to the actual state of different areas of the electrode. 2. In the process of changing the partition operation state, this invention does not immediately switch partitions simply because the charge migration front crosses the partition boundary. Instead, it first identifies the next partition as a candidate receiving partition. After the in-band tail quantity completes the actual cross-partition transfer, it then changes the main input partition, unloading partition, and tail quantity receiving partition. Before the ridge partition restores the common input, the charge migration trend and contact state are also checked by restoring the trial connection section. When the charge migration regresses or the contact unloading front shifts back, the candidate state can be cancelled, the transferred in-band tail quantity can be returned, and the original unloading path can be restored. Therefore, the switching of partition states corresponds to the actual position of local charge, which can reduce the local current re-accumulation caused by premature input restoration, premature switching, and migration regression, making the dynamic current modulation process have better continuity and recoverability. 3. This invention addresses situations where new and old misaligned bands may intersect, separate, or migrate in opposite directions within continuous input segments. It employs processes such as merging tail quantities within the same-direction band, cross-band continuation transfer, zone-by-zone unloading, and cancellation of tail quantities within the original band with those in the opposite direction. Furthermore, if the misaligned band separates prematurely before cross-band transfer is complete, the tail quantity already transferred into the band is redirected along its original path. Only after the remaining tail quantity in the opposite direction has been transferred and the previous misaligned band has closed is the subsequent rotation direction reversed. This avoids the superposition or frequent switching of main input, unloading, and tail quantity transfer paths formed by different input segments in local areas, and ensures continuous reception of local quantities that have not yet been transferred, thereby improving the stability of the multi-input segment dynamic modulation process and its adaptability to different local migration states. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the method flow of the present invention; Figure 2 This is a schematic diagram of the logic judgment of the present invention; Figure 3 This is a flowchart of the partitioned current modulation process of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention provides, for example Figures 1-3 The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation, as shown, includes the following steps: Step 1: Divide the ridge and two sides of the electrode into a ridge zone and two adjacent zones, and connect them with bidirectional transfer branches; Step 2: After the first input segment ends, obtain the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment. Determine the area between the two leading edges as the rebound migration misalignment zone, determine the front and rear partitions according to the migration direction, and determine the partition equalization charge within the misalignment zone as the tail quantity within the zone. Step 3: When the next input segment enters, the preceding partition is designated as the main input partition and receives the main input current. The ridge partition is designated as the unloading partition and outputs a low-amplitude unloading current through the bidirectional transfer branch. The following partition is designated as the tail quantity receiving partition and receives the unloading current and the in-band tail quantity. Step 4: When the leading edge of the power migration crosses the boundary of the adjacent partition, the main input partition, unloading partition, and tail quantity receiving partition are rotated along the direction of movement; Step 5: When the new misalignment band intersects with the previous misalignment band, merge the tail quantities of the two misalignment bands and the bands in the same direction and continue to rotate; when the two bands separate, unload the load area by area from the rear end of the previous misalignment band and restore the common input. Step 6: When the new misalignment band is in the opposite direction to the previous misalignment band, the tail quantity in the original band cancels out the reverse tail quantity, and the subsequent rotation direction is determined according to the remaining direction; after the misalignment band is closed, the corresponding partitions jointly receive the remaining input segments.

[0020] In one embodiment, the charging process of a lithium-ion battery with localized ridges on the surface of the negative electrode is used as the implementation object. Continuous height detection is performed on the electrode surface, and the localized areas continuously higher than the areas on both sides are identified as electrode ridges. The area containing the electrode ridge is divided into ridge partitions, and an adjacent partition is defined on each side of the ridge partition. The ridge partitions and the two adjacent partitions are arranged sequentially along the width direction of the electrode, and the adjacent partitions are connected by bidirectional transfer branches, enabling the local current between the partitions to transfer according to the actual migration direction.

[0021] The charging process is divided into multiple input segments in chronological order. After the first input segment ends, the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment are acquired. The ridge reference segment is determined based on the position of the ridge interval in the three partition arrangement directions and serves as a comparison benchmark for contact state changes and charge migration positions. The contact unloading leading edge segment is determined based on the thickness fall-off order or contact pressure fall-off order of each partition after the first input segment ends, and is used to indicate the boundary between areas that have completed contact state fall-off and areas that have not yet completed fall-off. The charge migration leading edge segment is determined based on the partition equalization current between adjacent partitions. By accumulating the migrated charge corresponding to the partition equalization current, the partition boundary where the charge transfer across regions is last completed along the migration direction is determined as the charge migration leading edge segment.

[0022] When the contact unloading leading edge and the charge migration leading edge are at different positions, it indicates that the decline process of the local contact state of the electrode is not synchronized with the charge migration process between zones. The area between the two leading edges is defined as the rebound migration misalignment zone, and the zone equalization charge within the misalignment zone that has not yet completed cross-zone transfer is defined as the zone tail quantity. According to the migration direction of the charge migration leading edge, the adjacent zone ahead of the migration direction is defined as the forward zone, and the other adjacent zone is defined as the rear zone.

[0023] When the next input segment arrives, the preceding section is designated as the main input section and receives the main input current. The ridge section is designated as the unloading section, causing it to output a low-amplitude unloading current to the following section via a bidirectional transfer branch. The following section is designated as the tail quantity receiving section, receiving both the low-amplitude unloading current and the in-band tail quantity. The low-amplitude unloading current can be determined based on the main input current, for example, it can be set to 10% to 20% of the main input current. The low-amplitude unloading current is used to guide the transfer of localized charge that has not yet completed migration within the ridge section to the following section, not to put the entire lithium-ion battery into a discharge state.

[0024] During the next input segment, the partition balancing current continues to be acquired and the charge migration leading edge segment position is updated. When the charge migration leading edge crosses the boundary of an adjacent partition, it indicates that the actual migration position of the in-band tail quantity has crossed the boundary of that partition. At this time, the main input partition, unloading partition, and tail quantity receiving partition are rotated along the movement direction of the charge migration leading edge, so that the function state of each partition changes with the migration position of the in-band tail quantity. After the rotation, the new main input partition receives the subsequent main input current, the new unloading partition outputs a low-amplitude unloading current, and the new tail quantity receiving partition receives the in-band tail quantity.

[0025] After the subsequent input segment ends, the contact unloading leading edge segment and the charge migration leading edge segment are acquired again, and a new misalignment zone is formed based on the positions of the two leading edges. When the new misalignment zone intersects with the previous misalignment zone, the two misalignment zones and the tail quantities within the zone with the same migration direction are merged, and the rotation of the zone action state continues along the same migration direction. When the new misalignment zone separates from the previous misalignment zone, it indicates that some zones at the rear end of the previous misalignment zone have separated from the locally incomplete migration area. Starting from the rear end of the previous misalignment zone, the low-amplitude unloading is released zone by zone, and the zones that have completed the transfer of tail quantities within the zone resume common input.

[0026] When the new misalignment band is in the opposite direction to the previous misalignment band, the tail quantity within the band formed by the new misalignment band in the opposite direction is taken as the reverse tail quantity, and the original tail quantity within the band is canceled out by the reverse tail quantity. If a tail quantity in the original direction still exists after cancellation, the rotation continues according to the original migration direction; if a reverse residual tail quantity is formed after cancellation, the subsequent rotation direction is determined according to the migration direction corresponding to the reverse residual tail quantity. When the contact unloading leading edge segment coincides with the charge migration leading edge segment, and the tail quantity within the band of the misalignment band has completed the cross-regional transfer, the rebound migration misalignment band is closed, so that the corresponding partitions jointly receive the remaining input segment.

[0027] Through the above process, based on the changes in the contact state of the electrode ridge area and the location of local charge migration, the main input, low-amplitude unloading and tail charge receiving relationships of different zones are dynamically adjusted so that the ridge area does not continue to receive the main input current when the local charge has not yet completed migration. This alleviates the local current concentration on the electrode, reduces the possibility of local lithium plating development, and reduces the charging efficiency loss caused by uniformly reducing the charging current of the entire cell.

[0028] Furthermore, the process of restoring the ridge partition from the unloaded partition to the common input partition includes: When the in-band tail quantity is transferred to the rear partition and the leading edge of the power migration crosses the ridge reference segment, the ridge partition is identified as a candidate recovery partition. A portion of the main input current is transferred from the front partition to the candidate recovery partition, while the front partition continues to receive the remaining main input current, and the rear partition continues to receive the in-band tail quantity, forming a recovery trial section. During the recovery trial section, if the leading edge of the power migration continues to move away from the ridge reference section along the original migration direction, and the leading edge of the contact unloading does not retreat back to the ridge reference section, the candidate recovery section will participate in the common input. When the leading edge of the power migration re-enters the range corresponding to the convex ridge reference segment, or when the leading edge of the contact unloading retreats to the convex ridge reference segment, the candidate recovery state of the candidate recovery partition is cancelled, the convex ridge partition is restored to output a low-amplitude unloading current to the subsequent partition, and the partition equalization power formed in the recovery test section is incorporated into the in-band tail quantity.

[0029] In one embodiment, during the process of low-amplitude unloading in the ridge partition and continuous in-band tail current in the rear partition, the charging control unit continues to acquire the leading edge segment of the power migration. When the in-band tail current has been transferred to the rear partition and the leading edge of the power migration crosses the ridge reference segment, it indicates that the original local residual power in the ridge partition has moved to the rear partition. However, at this time, the ridge partition is not directly restored to accept all main input current. Instead, the ridge partition is first identified as a candidate recovery partition.

[0030] After determining the candidate recovery zone, a portion of the main input current currently received by the preceding zone is diverted to the convex ridge zone, forming a recovery trial section. Within this trial section, the preceding zone continues to receive the remaining main input current, the following zone continues to receive the in-band tail current, and the convex ridge zone only receives the trial current. For example, the trial current can be set to 15%–30% of the current main input current to avoid the convex ridge zone directly receiving a large input current before the recovery conditions have stabilized.

[0031] After the trial connection is restored, continue to track the contact unloading front edge and the charge migration front edge. If the charge migration front edge continues to move away from the ridge reference edge along its original migration direction, it indicates that the trial connection current did not cause the local charge to re-accumulate in the ridge section. At the same time, if the contact unloading front edge does not retreat towards the ridge reference edge, it indicates that the local contact state of the ridge section remains stable. When both of the above states are maintained simultaneously, the candidate restoration section is allowed to participate in the common input.

[0032] After the ridge section participates in the common input, the front section and the ridge section jointly receive the main input current of the current input segment, and the rear section continues to receive the in-band tail quantity that has not yet been transferred. This makes the recovery process of the ridge section correspond to the local charge migration state and contact state, rather than directly recovering based solely on a preset time or a single current condition.

[0033] The range corresponding to the convex ridge reference segment is the position interval covered by the convex ridge partition along the arrangement direction of the three partitions. If, within the restored trial connection section, the leading edge of the electrical migration re-enters the range corresponding to the convex ridge reference segment, it indicates that some local electrical current has shifted back to the convex ridge partition; or if the leading edge of the contact unloading moves back towards the convex ridge reference segment, it indicates that the contact state of the convex ridge partition has not remained stable. In either case, the candidate restoration state of the convex ridge partition is revoked, the transfer of trial connection current to the convex ridge partition is stopped, and the convex ridge partition is made to output a low-amplitude unloading current to the subsequent partitions.

[0034] When canceling the trial connection, the balanced electricity generated between adjacent zones during the trial connection is accumulated and incorporated into the tail quantity within the original zone. This is then carried over by the subsequent zone, allowing the newly added local migration electricity during the trial connection to continue to be transferred along the original path, thus preventing it from being stuck in the ridge zone again.

[0035] Through the above process, before the convex ridge partition returns from the unloaded state to the common input state, a partial current trial connection and double leading edge verification are added to ensure that the recovery action is based on the continuous migration of local current and the fact that the contact state has not regressed. When the recovery conditions are unstable, the trial connection is cancelled in time and the low-amplitude unload is restored, thereby reducing the situation where the convex ridge partition prematurely re-accepts a large input current, causing the local current to concentrate again.

[0036] Furthermore, the rotation process of the main input partition, unloading partition, and tail quantity receiving partition includes: When the leading edge of the power migration crosses the boundary of the adjacent partition, the next partition in the migration direction is determined as the candidate receiving partition, and the current main input partition, unloading partition and tail quantity receiving partition are maintained. The in-band tail quantity currently received by the tail quantity receiving zone is transferred to the candidate receiving zone via a bidirectional transfer branch, and the newly formed zone equalization power during the transfer is continuously incorporated into the in-band tail quantity. After the in-band tail quantity is transferred, the current tail quantity receiving partition is changed to the main input partition, the current main input partition is changed to the unloading partition, and the candidate receiving partition is changed to the new tail quantity receiving partition. Before the in-band tail quantity completes the transfer, when the leading edge of the energy migration returns to the adjacent partition boundary it crossed, the candidate acceptance status of the candidate acceptance partition is cancelled, the transferred in-band tail quantity is sent back to the original tail quantity acceptance partition, and the original partition's function status is maintained.

[0037] In one embodiment, as the power migration front moves along the partition arrangement direction, the charging control unit continuously acquires the partition balancing current between adjacent partitions and determines the position of the power migration front based on the direction of the partition balancing current and the accumulated migrated power. When the power migration front crosses the boundary of the current adjacent partition, it indicates that the in-band tail quantity has begun to move from the current tail quantity receiving partition to the next partition in the migration direction. At this time, the next partition is first determined as a candidate receiving partition, without immediately changing the active state of the current main input partition, unloading partition, and tail quantity receiving partition.

[0038] Once the candidate receiving zone is determined, the current main input zone continues to receive the main input current, the current unloading zone continues to output a low-amplitude unloading current, and the bidirectional transfer branch between the current tail quantity receiving zone and the candidate receiving zone is activated, allowing the in-band tail quantity in the current tail quantity receiving zone to enter the candidate receiving zone along the direction of quantity migration. Therefore, the original current receiving relationship does not switch prematurely before the actual migration of the in-band tail quantity is completed.

[0039] During the in-band tail quantity transfer, the bidirectional transfer branch continues to collect the partition equalization current between adjacent partitions and accumulate it. If a new partition equalization quantity is formed during the transfer process due to the continuous effect of the main input current and the low-amplitude unloading current, the newly formed partition equalization quantity will be continuously included in the current in-band tail quantity and will continue to be transferred to the candidate receiving partition, so as to avoid the newly formed local quantity from deviating from the original migration path.

[0040] When the in-band tail quantity in the current tail quantity receiving partition and the partition balancing quantity formed during the transfer have all been transferred to the candidate receiving partition, the in-band tail quantity transfer is confirmed to be complete. After the transfer is completed, the original tail quantity receiving partition is converted into a new main input partition, the original main input partition is converted into a new unloading partition, and the candidate receiving partition is converted into a new tail quantity receiving partition, so that the partition operation state completes one rotation along the direction of quantity migration.

[0041] After the rotation is completed, the new main input zone receives the subsequent main input current, the new offload zone outputs a low-amplitude offload current through the bidirectional transfer branch, and the new tail quantity receiving zone receives the in-band tail quantity that has been transferred in, as well as the subsequent zone equalization charge. The change in the zone's operating state is triggered by the actual position of the in-band tail quantity, rather than simply by the positional change of the charge migration front crossing the zone boundary.

[0042] If the in-band tail quantity has not yet completed its transfer and the leading edge of the energy migration returns to the previously crossed adjacent partition boundary, it indicates that the migration trend of the in-band tail quantity has not remained stable. In this case, the candidate acceptance status of the candidate acceptance partition is revoked, and the corresponding bidirectional transfer branch is reversed to send the in-band tail quantity that has entered the candidate acceptance partition back to the original tail quantity acceptance partition. The active states of the main input partition, unloading partition, and tail quantity acceptance partition before the rotation are maintained. Once the leading edge of the energy migration crosses the adjacent partition boundary again, the candidate acceptance and tail quantity transfer process is re-executed.

[0043] Through the above process, after the leading edge of the energy migration crosses the partition boundary, the actual cross-regional transfer of the in-band tail quantity is completed first, and then the operating state of each partition is rotated. When the migration trend regresses, the candidate acceptance is cancelled and the original current path is restored, thereby avoiding the situation where the operating state of the partition has changed but the in-band tail quantity is still stuck in the original partition, so that the relationship between the main input, low-amplitude unloading and tail quantity acceptance is consistent with the actual migration position of the local energy.

[0044] Furthermore, the processing procedure when a new misalignment zone intersects with a previous misalignment zone includes: The overlapping partitions of the two misaligned bands are identified as cross-band transfer partitions, and the unloaded state of the cross-band transfer partitions is maintained. This causes the in-band tail of the previous misaligned band to enter the cross-band transfer zone along the original migration direction, and restricts the cross-band transfer zone from participating in the main input current of any misaligned band. After the tail quantity within the band of the previous misaligned band enters the non-overlapping partition of the new misaligned band through the cross-band transfer partition, it is merged into the tail quantity within the same band of the new misaligned band, and the non-overlapping partition is determined as the tail quantity receiving partition of the new misaligned band. Before the tail quantity within the previous misaligned band completes the cross-band transfer, when the two misaligned bands change from intersecting to separating, the cross-band transfer stops, the tail quantity within the band that has entered the cross-band transfer partition is returned to the original tail quantity receiving partition of the previous misaligned band, and the two misaligned bands resume partition rotation respectively.

[0045] In one embodiment, during the charging process of multiple consecutive input segments, the rebound migration misalignment zone formed by the previous input segment has not yet closed, and a new misalignment zone is formed after the subsequent input segment ends. When the new misalignment zone and the previous misalignment zone have an overlapping area in the partition arrangement direction, it indicates that the local charge that has not yet been transferred in the previous input segment overlaps with the local migration area formed by the new input segment. The partition jointly covered by the two misalignment zones is determined as the cross-band transition partition.

[0046] Once the cross-band transfer zone is determined, its unloaded state is maintained, preventing it from directly receiving the main input current corresponding to any misaligned zone. At this time, the cross-band transfer zone mainly serves as the transfer function between the previous misaligned zone and the new misaligned zone, avoiding the zone from continuing to receive the main input current while receiving the cross-band transferred electricity, thus preventing different current paths from superimposing in the overlapping area.

[0047] The charging control unit, following the original migration direction of the tail quantity within the previous misaligned band, activates the bidirectional transfer branch between the tail quantity receiving section and the cross-band transfer section of the previous misaligned band, allowing the tail quantity within the previous misaligned band to first enter the cross-band transfer section. During this process, the main input section and unloading section corresponding to the previous misaligned band continue to operate in their original states, and the section corresponding to the new misaligned band does not temporarily utilize the cross-band transfer section to receive the main input current.

[0048] When the tail quantity within the current misaligned zone enters the non-overlapping partition of the new misaligned zone via the cross-zone transfer partition, this portion of the tail quantity within the current zone is merged with the tail quantity within the new misaligned zone that migrates in the same direction. The merged tail quantity is then received by the non-overlapping partition. The non-overlapping partition is thus determined as the tail quantity receiving partition of the new misaligned zone, and the subsequent partitioning status continues to rotate according to the migration direction of the merged tail quantity within the current zone.

[0049] For example, when the tail quantity within the band of the previous misaligned band migrates from the first adjacent partition to the second adjacent partition, and the tail quantity within the band of the new misaligned band also migrates in the same direction, the overlapping partitions of the two misaligned bands can be used to complete the transfer. This allows the tail quantity within the band of the previous misaligned band that has not yet been processed to enter the non-overlapping area of ​​the new misaligned band and continue to be processed along the same migration path as the newly formed tail quantity within the same band in the same direction. There is no need to establish two intersecting tail quantity transfer paths separately.

[0050] If the tail quantity within the previous misaligned zone has not yet completed the cross-zone transfer, and the two misaligned zones change from an intersecting state to a separated state, it indicates that the overlapping area is no longer suitable as a cross-zone transfer path. At this time, the tail quantity within the zone is stopped from entering the cross-zone transfer partition. The tail quantity within the zone that has already entered the cross-zone transfer partition is returned to the original tail quantity receiving partition of the previous misaligned zone along the original transfer path. The common transfer relationship between the cross-zone transfer partition and the two misaligned zones is terminated, so that the previous misaligned zone and the new misaligned zone are partitioned and rotated according to their respective migration directions.

[0051] Through the above process, when the new misaligned band intersects with the previous misaligned band, the tail quantity in the same direction band is transferred by using the overlapping partition, and the main input current is restricted to the overlapping partition during the transfer. When the two misaligned bands separate in advance, the cross-band transfer is terminated in time and the tail quantity in the band that has been transferred is returned, thereby reducing the superposition of the main input, unloading and tail quantity acceptance relationship in the overlapping area, so that the power transfer path between the new and old misaligned bands remains clear.

[0052] Furthermore, the processing procedure when the new misalignment band is in the opposite direction to the previous misalignment band includes: The reverse tail quantity formed by the new misalignment band is introduced into the bidirectional transfer branch, forming a counteracting segment with the tail quantity in the original band of the previous misalignment band, and maintaining the function state of the main input partition, unloading partition and tail quantity receiving partition corresponding to the previous misalignment band before the counteracting is completed. When the reverse tail quantity is less than the original tail quantity, the remaining original tail quantity after cancellation is retained in the original tail quantity receiving partition, maintaining the original partition rotation direction, and restricting the new misaligned band from starting reverse rotation. When the reverse tail quantity equals the original tail quantity, the original tail quantity and the reverse tail quantity cancel each other out, and the opposing cancellation segment ends, maintaining the current partitioning state until the leading edge of the charge migration crosses the adjacent partition boundary corresponding to the new misalignment band. When the reverse tail quantity is greater than the original tail quantity, the excess portion is identified as the reverse residual tail quantity and transferred to the partition behind the new misalignment band. After the reverse residual tail quantity is transferred and the previous misalignment band is closed, the rotation direction of the main input partition, the unloading partition, and the tail quantity receiving partition is reversed.

[0053] In one embodiment, before the previous misalignment band is closed, a new misalignment band is formed after the subsequent input segment ends, and the direction of energy migration corresponding to the new misalignment band is opposite to that of the previous misalignment band. At this time, the partition balancing energy that has not yet completed cross-regional transfer in the opposite direction within the new misalignment band is determined as the reverse tail quantity, and the in-band tail quantity that has not yet completed transfer in the previous misalignment band is taken as the original in-band tail quantity.

[0054] After determining the reverse tail quantity, the corresponding bidirectional transfer branch is activated, allowing the reverse tail quantity to enter the transfer path connected to the tail quantity within the original band along its migration direction, forming a counter-offsetting segment. The charging control unit cancels out the tail quantity within the original band and the reverse tail quantity based on the cumulative migration amount in both directions of the bidirectional transfer branch. Before the cancellation is completed, the active states of the main input partition, unloading partition, and tail quantity receiving partition corresponding to the previous misalignment band are maintained, and the partition rotation direction is not immediately reversed due to the change in the direction of the new misalignment band.

[0055] When the reverse tail quantity is less than the original tail quantity, after the reverse tail quantity is completely canceled out, there is still a remaining tail quantity in the original tail quantity direction. At this time, the remaining tail quantity in the original tail quantity direction is retained in the original tail quantity receiving zone, maintaining the original zone rotation direction, and the new misaligned zone is temporarily not allowed to start reverse rotation. For example, when the original tail quantity is 12mAh and the reverse tail quantity is 8mAh, the remaining 4mAh after cancellation will still be transferred in the original migration direction until this part of the charge is transferred across zones.

[0056] When the reverse tail quantity equals the original in-band tail quantity, the two cancel each other out and no longer form a residual tail quantity with a clear migration direction. The opposing cancellation segment ends, and the current main input partition, unloading partition, and tail quantity receiving partition maintain their active states. At this time, instead of immediately rotating in the reverse direction, the current energy migration leading edge corresponding to the new misalignment band is acquired. When the energy migration leading edge crosses the boundary of the adjacent partition, the direction of change of the partition's active state is determined based on the subsequently formed in-band tail quantity.

[0057] When the reverse tail quantity is greater than the original tail quantity, the original tail quantity is completely canceled out, and the portion exceeding the original tail quantity is determined as the reverse residual tail quantity. For example, when the original tail quantity is 12mAh and the reverse tail quantity is 16mAh, the excess 4mAh is taken as the reverse residual tail quantity. The reverse residual tail quantity is transferred to the rear partition of the new misalignment band through a bidirectional transfer branch, and the rear partition takes over the reverse residual tail quantity.

[0058] While the reverse residual tail quantity has not yet been transferred or the previous misalignment band has not yet closed, the original partition's operating state continues to be maintained to avoid simultaneous rotation in the original direction and rotation in the reverse direction. Once the reverse residual tail quantity has been transferred and the previous misalignment band has closed, the rotation direction of the main input partition, unloading partition, and tail quantity receiving partition is reversed, so that the operating state of subsequent partitions changes along the migration direction corresponding to the new misalignment band.

[0059] Through the above process, when the new and old misalignment bands are in opposite directions, the remaining migration direction is first determined based on the actual size of the tail quantity in the original band and the reverse tail quantity, instead of immediately reversing the partition operation state after detecting a change in direction. This avoids reciprocating reversal when the local power has not been processed, reduces mutual interference between the main input, unloading and tail quantity transfer paths in different directions, and ensures that the subsequent rotation direction is consistent with the actual migration direction of the remaining tail quantity.

[0060] Furthermore, the process of obtaining the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment includes: Obtain the surface height sequence of the electrode along the ridge partition and the arrangement direction of two adjacent partitions. Determine the interval that is continuously higher than the adjacent positions on both sides as the ridge interval, and determine the partition position corresponding to the ridge interval as the ridge reference segment. After the first input segment ends, according to the thickness reduction order of the ridge partition and the two adjacent partitions, the boundary between the partition that has continuously completed the thickness reduction along the reduction direction and the partition that has not yet completed the thickness reduction is determined as the contact unloading front edge segment. Obtain the partition balance current between adjacent partitions, accumulate the migrated electricity in each partition according to the flow direction of the partition balance current, and determine the partition boundary where the electricity transfer across partitions is last completed along the migration direction as the leading edge segment of electricity migration.

[0061] In one embodiment, the surface contour of the coated and rolled negative electrode sheet is detected, with the detection direction consistent with the arrangement direction of the ridge partitions and two adjacent partitions. A laser displacement detection component can be used to continuously acquire the surface height values ​​of the electrode sheet at intervals of 0.5 mm to 1 mm, and form a surface height sequence according to the order of detection positions. The surface height sequence is continuously compared, and when the height values ​​of a certain continuous interval are all higher than the adjacent positions on both sides, the continuous interval is determined as the ridge interval.

[0062] Once the ridge region is determined, the corresponding section position of the ridge region is defined as the ridge reference segment based on the divided ridge partitions and two adjacent partitions. During this charging process, the ridge reference segment remains unchanged and is used to compare the movement of the contact unloading front and the charge migration front relative to the ridge region, avoiding changes in the common position reference of the two fronts due to changes in the detection position.

[0063] Local thickness detection positions are set at the ridge section corresponding to the battery and at two adjacent sections. During the first input segment, the electrode thickness changes due to local polarization and lithium intercalation. After the first input segment ends, the thickness value at each detection position at the end of the input segment is used as the starting point for the thickness fallback, and the thickness change of each section is continuously acquired. When the thickness change of a certain section falls back to a preset stable range, it is determined that the thickness fallback of that section is complete.

[0064] The order in which the thickness reduction of each of the three partitions is completed is compared along the arrangement direction. If a preceding consecutive partition has completed thickness reduction, but its adjacent subsequent partition has not, the boundary between the consecutive partition that has completed thickness reduction and the partition that has not yet completed thickness reduction is determined as the contact unloading leading edge segment. As subsequent partitions gradually complete thickness reduction, the contact unloading leading edge segment moves in the corresponding direction, thereby reflecting the position reached by the local contact state release.

[0065] Current acquisition components are installed in the bidirectional transfer branches between adjacent zones to acquire the magnitude and direction of the current within the branch. The charging control unit accumulates the zone balancing current according to a preset sampling period to obtain the transferred energy corresponding to the boundaries of each adjacent zone, and determines the zone boundaries through which the zone balancing energy passes based on the accumulation results. When the zone balancing energy of a certain zone has passed the next zone boundary in the migration direction, it is determined that the zone boundary has completed the inter-zone energy transfer, and the zone boundaries that have completed the inter-zone energy transfer are recorded sequentially along the migration direction of the zone balancing current.

[0066] At the same detection point, the boundary of the zone where the last cross-zone transfer of electricity is completed along the migration direction is determined as the leading edge segment of electricity migration. If the boundary of the zone near the ridge has completed the cross-zone transfer, but the boundary of the next zone far from the ridge has not yet completed the cross-zone transfer, the leading edge of electricity migration remains at the boundary of the previous zone until the electricity migration corresponding to the next zone boundary is completed before moving forward.

[0067] Through the above process, the reference segment of the convex ridge is determined by the electrode surface height sequence, the contact unloading front segment is determined by the spatial order of thickness fallback in each zone, and the charge migration front segment is determined by the actual charge migration between adjacent zones, giving each of the three segments a clear data source and positional meaning. This allows for the differentiation between the fallback position of a local contact state of the electrode and the actual local charge migration position, providing a basis for subsequently determining the rebound migration misalignment zone and adjusting the current carrying capacity relationship of each zone.

[0068] Furthermore, the zone-by-zone unloading process after the separation of the two misaligned bands includes: Starting from the end of the previous misalignment zone, the judgment is performed zone by zone according to the order in which each zone is removed from the previous misalignment zone. When a certain partition is completely removed from the previous misalignment band and the new misalignment band, and the in-band tail quantity in that partition has been transferred to the adjacent partition, the low-amplitude unloading current output by that partition is released, and that partition participates in the common input. If the current partition has not yet escaped any misalignment zone, or if the in-band tail quantity within the partition has not yet been transferred, suspend the release of the partition and its subsequent partitions. When the first two misaligned bands intersect again after the area-by-area removal is completed, the subsequent removal is stopped, so that the unremoved sections continue to be unloaded, and the sections that have been removed but have re-entered the misaligned band resume outputting a low-amplitude unloading current, and the sections are incorporated into the re-merged misaligned band.

[0069] In one embodiment, after the previous misalignment band and the new misalignment band change from an intersecting state to a separated state, the charging control unit does not simultaneously release the unloading state of the partitions involved in the two misalignment bands. Instead, it uses the rear end of the previous misalignment band as the release starting point and judges each partition in the order in which they detached from the previous misalignment band. The rear end of the previous misalignment band is the partition position located on one side of the end along the original migration direction of the previous misalignment band. Starting the release from this position allows the partitions that have completed partial power migration to restore common input first.

[0070] When judging the current partition to be released, the positional relationship between the partition and the previous misalignment band and the new misalignment band is obtained, and it is determined whether there are still in-band tail quantities that have not yet been transferred within the partition. When the current partition has simultaneously separated from the previous misalignment band and the new misalignment band, and the in-band tail quantities within the partition have been transferred to the adjacent partition via the bidirectional transfer branch, it indicates that the partition is no longer in the local incomplete migration area corresponding to the two misalignment bands. At this time, the low-amplitude unloading current output of the partition is released, and the partition participates in the common input of the current input segment.

[0071] After the current partition participates in the common input, the next adjacent partition that has not yet been released will be taken as the new partition to be released, and the same judgment will continue to be made according to the same conditions. The partition that has been released and unloaded will share the input current with the original common input partition, while the partition that has not yet been released will continue to maintain a low-amplitude unloading or tail-end bearing state, so that the release process will advance from the end of the previous misalignment band forward zone by zone.

[0072] If the current partition is still within the previous or new misalignment zone, it indicates that the partition is still affected by the local migration process corresponding to at least one misalignment zone; or, although the current partition has escaped two misalignment zones, the residual quantities within its zone have not yet been transferred to adjacent partitions, so the release of the current partition and its subsequent partitions is paused. During the pause, the current partition continues to maintain its original operational state and completes the transfer of the remaining residual quantities within the zone through bidirectional transfer branches, avoiding the release sequence from skipping partitions where there is still local charge retention.

[0073] If, before the zone-by-zone release is complete, changes in the contact unloading front and the charge migration front cause the previous misalignment zone to intersect with the new misalignment zone again, the release of subsequent zones will be stopped. Zones that have not yet been released will continue to be in the unloading state; zones that have been released but have re-entered the misalignment zone due to the re-intersection of two misalignment zones will re-output a low-amplitude unloading current and be incorporated into the re-merged misalignment zone. Subsequently, the zone's operational state will continue to be adjusted according to the migration direction of the merged misalignment zone.

[0074] Through the above process, after the two misaligned bands separate, the common conditions for unloading are the actual separation of the partition from the misaligned band and the completion of the transfer of the tail quantity within the band. The common input is restored zone by zone according to the partition order, which can prevent partitions with local power retention from being unloaded prematurely. When the two misaligned bands intersect again, the partitions that re-enter the misaligned band can be restored to the unloading state, thereby maintaining the correspondence between the partition current connection relationship and the local power migration state.

[0075] Furthermore, the process of determining the closure of the springback migration misalignment zone includes: When the contact unloading front segment coincides with the charge migration front segment, determine whether there is any in-band tail quantity within the rebound migration misalignment band that has not yet completed cross-zone transfer; When the two leading edge segments overlap and there is no in-band tail volume that has not yet completed cross-regional transfer, the rebound migration misalignment zone is determined to be closed. When the two leading edge segments overlap, but there are still tail quantities within the band that have not yet completed cross-regional transfer, maintain the transfer direction of the current tail quantity receiving zone and bidirectional transfer branch until the tail quantity within the band completes cross-regional transfer, and then determine the closure of the rebound migration misalignment zone. When the two leading edge segments separate again before the tail quantity in the band completes the cross-regional transfer, the rebound migration misalignment zone is redefined based on the two leading edge segments after the re-separation, and the tail quantity in the band that has not yet completed the cross-regional transfer is incorporated into the redefined rebound migration misalignment zone.

[0076] In one embodiment, as the rebound migration misalignment band gradually shrinks during the charging process, the charging control unit continuously acquires the contact unloading leading edge segment and the charge migration leading edge segment, and determines whether the misalignment band meets the closure conditions according to the partition positions corresponding to the two leading edges. When the two leading edges move to the same partition boundary or the same segment, it indicates that the fall-off position of the local contact state coincides with the charge migration position. However, at this time, it is not directly determined that the rebound migration misalignment band is closed, but it is further checked whether there is still any in-band tail quantity within the misalignment band that has not yet completed the cross-regional transfer.

[0077] The remaining status of the in-band tail quantity can be determined based on the initial in-band tail quantity in the tail quantity receiving partition, the cumulative migration charge output by the bidirectional transfer branch, and the newly formed partition balancing charge during the transfer. When the initial in-band tail quantity and the subsequently formed partition balancing charge have both completed cross-region transfer through the bidirectional transfer branch, it is determined that there is no in-band tail quantity that has not yet completed cross-region transfer. At this time, the positional relationship between the two leading edges and the local charge transfer state both satisfy the closure condition, confirming that the rebound migration misalignment band is closed, and enabling the corresponding partition to jointly receive the remaining input segment.

[0078] If the contact unloading leading edge segment and the charge migration leading edge segment have overlapped, but some in-band tail quantity remains within the tail quantity receiving zone that has not yet been transferred, then the closure of the rebound migration misalignment zone is temporarily uncertain. The charging control unit maintains the current operational state of the tail quantity receiving zone while maintaining the original transfer direction of the bidirectional transfer branch, allowing the remaining in-band tail quantity to continue transferring to the adjacent zone in the migration direction. During this period, the unloading state of the corresponding zone is not prematurely released because the two leading edges have overlapped.

[0079] After all the remaining residual quantity within the band has completed its cross-zone transfer, it is confirmed again that the contact unloading leading edge segment and the charge migration leading edge segment are still in an overlapping state, and the closure of the rebound migration misalignment band is determined accordingly. If the two leading edges have separated again when the residual quantity within the band has completed its transfer, the previous closure judgment is not used, but the rebound migration misalignment band is re-determined based on the new position after the separation of the two leading edges.

[0080] If the contact unloading leading edge segment and the charge migration leading edge segment separate again before the remaining tail quantity within the band completes its transfer, it indicates that the local contact state and the charge migration process are no longer synchronized. At this time, the rebound migration misalignment band is redefined based on the two leading edges after the re-separation, and the tail quantity within the band that has not yet completed its cross-regional transfer continues to be the tail quantity within the band of the redefined rebound migration misalignment band. The current tail quantity receiving zone continues to receive and transfer the tail quantity according to the original or redefined migration direction.

[0081] Through the above process, the overlap of the positions of the two leading edges is taken as the initial condition for the closure of the misaligned zone, and the completion of the cross-regional transfer of the tail quantity within the zone is taken as the further confirmation condition, so as to avoid prematurely restoring the common input just because the two leading edges temporarily overlap; when the leading edges separate again, the tail quantity within the zone that has not yet completed the transfer can continue to be included in the new misaligned zone for processing, thereby keeping the misaligned zone closure state consistent with the actual migration result of local electrical quantities.

[0082] Furthermore, the rotation of the zone's operational status is carried out zone by zone according to the order in which each zone is arranged along the direction of energy migration; In-band tail quantities are transferred only between adjacent partitions via bidirectional transfer branches. When the in-band tail quantity in the current tail quantity receiving partition has not yet been transferred out, the next partition in the migration direction will not participate in the subsequent rotation. After the in-band tail quantity completes its transfer to the adjacent partition, the adjacent partition that received the in-band tail quantity is used as the tail quantity receiving partition for subsequent rotation.

[0083] In one embodiment, the ridge partition and two adjacent partitions are arranged sequentially according to the direction of charge migration, and the adjacent partitions are connected by bidirectional transfer branches. When the partition's operating state changes, the operating state of the subsequent partition is not changed directly by skipping the intermediate partition, but rather by changing each partition sequentially according to the order of their arrangement in the direction of charge migration, so that the transfer path of the in-band tail quantity is consistent with the order of changes in the partition's operating state.

[0084] When the current tail quantity receiving partition needs to transfer the in-band tail quantity to the next adjacent partition in the migration direction, the charging control unit activates the bidirectional transfer branch between the two partitions, allowing the in-band tail quantity to enter the next adjacent partition from the current tail quantity receiving partition. During the transfer process, the current tail quantity receiving partition continues to maintain its original function, and the next adjacent partition does not participate in the subsequent rotation in advance, avoiding the situation where two partitions simultaneously undertake the function of receiving subsequent tail quantities before the in-band tail quantity has left the current partition.

[0085] In-band tail quantities are transferred zone by zone only through bidirectional transfer branches between adjacent partitions. For example, when an in-band tail quantity needs to move from the first adjacent partition to the second adjacent partition, the transfer between the first adjacent partition and the ridge partition is completed first, and then the transfer between the ridge partition and the second adjacent partition is completed according to the subsequent migration direction. The in-band tail quantity is not directly sent to the second adjacent partition by skipping the ridge partition. This allows each partition through which the in-band tail quantity passes to complete the acceptance and transfer in sequence.

[0086] While the in-band tail quantity in the current tail quantity receiving partition has not yet been transferred out, the current main input partition, unloading partition, and tail quantity receiving partition remain active, and the next partition in the migration direction is prohibited from entering subsequent rotations. If a new partition balancing charge is generated during the transfer, it will continue to be included in the current in-band tail quantity and transferred to the next adjacent partition through the currently activated bidirectional transfer branch.

[0087] Once the in-band tail quantities in the current tail quantity receiving partition and the newly formed partition equalization quantity during the transfer have all entered the next adjacent partition, the next adjacent partition that actually receives the in-band tail quantities is determined as the tail quantity receiving partition for the subsequent rotation. Then, according to the direction of quantity migration, the main input, unloading, and tail quantity receiving status of the corresponding partition are changed so that the next rotation continues to use this tail quantity receiving partition as the transfer starting point for the in-band tail quantities.

[0088] If the power migration direction reverses before the in-band tail quantity completes the transfer, the next partition will stop participating in the rotation, and the in-band tail quantity that has entered the next adjacent partition will be returned to the current tail quantity receiving partition according to the original transfer path. The partition-by-partition transfer will be performed after the power migration direction stabilizes again, thereby avoiding the partition function state jump caused by a brief change in migration direction.

[0089] Through the above process, the in-band tail quantity can only be transferred between adjacent partitions according to the actual migration direction. The completion of the in-band tail quantity transfer is a prerequisite for the next partition to participate in the rotation. This can avoid cross-regional jumps or premature rotations of the partition's active state, and ensure that the change of the tail quantity receiving partition is consistent with the actual position of the in-band tail quantity. This further guarantees the continuity of the main input, low-amplitude unloading, and tail quantity receiving path.

[0090] Furthermore, the process of transferring in-band tail quantity across bands via the crossband transfer zone includes: Establish connections between the original tail quantity receiving zone of the previous misalignment zone and the cross-zone transfer zone, as well as between the cross-zone transfer zone and the non-overlapping zone of the new misalignment zone, forming a directional continuation path along the original migration direction. After all the in-band tails leave the original tail receiving partition, disconnect the connection between the original tail receiving partition and the cross-band transfer partition, and maintain the connection between the cross-band transfer partition and the non-overlapping partition until all the in-band tails enter the non-overlapping partition. Before all the tail quantities in the band enter the non-overlapping partition, when the two misaligned bands change from intersecting to separating, the reverse guiding direction continuation path will sequentially return the tail quantities in the band that have entered the non-overlapping partition and the cross-band transition partition to the original tail quantity receiving partition. After the cross-band transfer or return is completed, the connection formed between the previous misaligned band and the new misaligned band through the cross-band transfer partition is disconnected, and the bidirectional transfer branches within each misaligned band are restored.

[0091] In one embodiment, after the previous misalignment band intersects with the new misalignment band and the cross-band transfer zone is determined, the charging control unit controls the bidirectional transfer branch to establish a cross-band transfer path according to the original migration direction of the previous misalignment band. The cross-band transfer path includes a first connected segment between the original tail quantity receiving zone of the previous misalignment band and the cross-band transfer zone, and a second connected segment between the cross-band transfer zone and the non-overlapping zone of the new misalignment band. The two connected segments together form a directional connection path from the previous misalignment band to the new misalignment band.

[0092] After the directional connection path is formed, the unloading state of the cross-band transfer zone is maintained, and the tail quantity within the band of the previous misaligned band enters the cross-band transfer zone from the original tail quantity receiving zone, and then enters the non-overlapping zone of the new misaligned band from the cross-band transfer zone. During the transfer process, the flow direction and cumulative transfer amount of the tail quantity within the band are obtained by current acquisition components set on the two connected segments, respectively, to determine whether the tail quantity within the band has left the original tail quantity receiving zone and whether it has completely entered the non-overlapping zone.

[0093] Once all the in-band tails of the current misaligned band have left the original tail receiving partition, the first connection segment between the original tail receiving partition and the cross-band transfer partition is disconnected to prevent the original tail receiving partition, which has already completed its output, from continuing to participate in the cross-band transfer. Simultaneously, the second connection segment between the cross-band transfer partition and the non-overlapping partition is maintained, allowing the in-band tails temporarily located within the cross-band transfer partition to continue entering the non-overlapping partition. This process continues until there are no more in-band tails yet to be transferred out within the cross-band transfer partition, at which point it is confirmed that all in-band tails have entered the non-overlapping partition of the new misaligned band.

[0094] After all the tail quantities within the band enter the non-overlapping partition, this non-overlapping partition continues to serve as the tail quantity receiving partition for the new misaligned band. It receives the merged tail quantities within the band and performs subsequent transfers according to the migration direction corresponding to the new misaligned band. At this point, the cross-band transfer partition ends the transfer of tail quantities within the previous misaligned band and no longer maintains the cross-band connectivity between the previous misaligned band and the new misaligned band.

[0095] If, before all the trailing quantities within the band enter the non-overlapping partition, the previous misaligned band and the new misaligned band change from intersecting to separating, then the cross-band transfer along the original migration direction stops, and the reverse guidance directional continuation path is initiated. During reverse guidance, the trailing quantities within the band that have already entered the non-overlapping partition are first returned to the cross-band transfer partition. Then, the original trailing quantities within the cross-band transfer partition, along with the returned trailing quantities, are sent back to the original trailing quantity receiving partition of the previous misaligned band, so that the trailing quantities within the band that have crossed different connected segments during the cross-band transfer process return sequentially along the original path.

[0096] After the in-band tail quantity completes the cross-band transfer or reverse return, the connection formed between the previous misaligned band and the new misaligned band via the cross-band transition zone is disconnected, and the original connection state of the bidirectional transfer branches within each misaligned band is restored. The previous misaligned band and the new misaligned band then continue to perform in-band tail quantity transfer and zone operation state rotation according to their respective charge migration directions, to prevent the cross-band path from continuing to affect the current flow direction within each misaligned band after the transfer or return is completed.

[0097] Through the above process, the cross-band transfer path is divided into two consecutive connected segments. Based on the actual position of the tail quantity in each partition, the corresponding connected segments are disconnected or reversed in sequence. This allows the tail quantity in the band to complete the transfer between the old and new misaligned bands according to a clear path. When the two misaligned bands separate in advance, the tail quantity in the band that has entered the cross-band transfer partition and non-overlapping partition can be returned in sequence, thereby avoiding the tail quantity in the band from being stuck in the cross-band path and making the branch state after the cross-band transfer compatible with the subsequent independent rotation of each misaligned band.

[0098] In other embodiments, the lithium plating suppression process for lithium-ion batteries based on dynamic current modulation can also be implemented in conjunction with improvements to electrode materials, electrolytes, separators, and basic charging parameters. The negative electrode can be made of modified graphite or coated silicon-carbon negative electrode materials to improve the intercalation conditions of lithium ions in the negative electrode active material; film-forming additives can be added to the electrolyte to form a relatively uniform solid electrolyte interface film on the negative electrode surface, and the lithium salt concentration can be adjusted according to the battery system to improve lithium ion transport conditions within the cell; the separator can be a ceramic-coated separator with an alumina coating to improve the separator's heat resistance and puncture resistance.

[0099] During electrode processing, the surface roughness of the electrode can be reduced by adjusting the rolling parameters or by surface leveling treatment, thereby reducing the degree of local protrusion formation. When the battery is under low temperature, high rate charging, or close to the charging limit, the battery management system can implement basic current reduction, segmented constant current charging, or charging limit restriction on the entire cell. Under the above basic control conditions, the partitioned current modulation process in this embodiment continues to adjust the main input, low-amplitude unloading, and tail-end load acceptance relationships of different partitions according to the contact unloading front and charge migration front of the ridge area.

[0100] The aforementioned materials, structures, and basic charging control measures are used to improve the overall lithium-ion transport conditions and safety of the battery, while the dynamic current modulation process is used to address the issues of localized ridges on the electrode and asynchronous contact states and charge migration between adjacent areas. When these two are used in combination, the process of determining the rotation of the rebound migration misalignment zone, the tail quantity within the zone, and the zoned action state remains unchanged.

[0101] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lithium-ion battery lithium plating suppression process based on dynamic current modulation, characterized in that, Includes the following steps: Step 1: Divide the ridge and two sides of the electrode into a ridge zone and two adjacent zones, and connect them with bidirectional transfer branches; Step 2: After the first input segment ends, obtain the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment. Determine the area between the two leading edges as the rebound migration misalignment zone, determine the front and rear partitions according to the migration direction, and determine the partition equalization charge within the misalignment zone as the tail quantity within the zone. Step 3: When the next input segment enters, the preceding partition is determined as the main input partition and receives the main input current, the ridge partition is determined as the unloading partition and outputs a low-amplitude unloading current through the bidirectional transfer branch, and the following partition is determined as the tail quantity receiving partition and receives the unloading current and the in-band tail quantity. Step 4: When the leading edge of the power migration crosses the boundary of the adjacent partition, the main input partition, unloading partition, and tail quantity receiving partition are rotated along the direction of movement; Step 5: When the new misalignment band intersects with the previous misalignment band, merge the tail quantities of the two misalignment bands and the bands in the same direction and continue to rotate; when the two bands separate, unload the load area by area from the rear end of the previous misalignment band and restore the common input. Step 6: When the new misalignment band is in the opposite direction to the previous misalignment band, the tail quantity in the original band cancels out the reverse tail quantity, and the subsequent rotation direction is determined according to the remaining direction; after the misalignment band is closed, the corresponding partitions jointly receive the remaining input segments.

2. The lithium-ion battery lithium plating suppression process based on dynamic current modulation according to claim 1, characterized in that, The process of restoring the ridge partition from the unloaded partition to the common input partition includes: When the in-band tail quantity is transferred to the rear partition and the leading edge of the power migration crosses the ridge reference segment, the ridge partition is determined as a candidate recovery partition. A portion of the main input current is transferred from the front partition to the candidate recovery partition, while the front partition continues to receive the remaining main input current, and the rear partition continues to receive the in-band tail quantity, forming a recovery trial section. Within the recovery test section, when the leading edge of the power migration continues to move away from the convex ridge reference section along the original migration direction, and the leading edge of the contact unloading does not retreat towards the convex ridge reference section, the candidate recovery partition participates in the common input. When the leading edge of the power migration re-enters the range corresponding to the convex ridge reference segment, or when the leading edge of the contact unloading retreats to the convex ridge reference segment, the candidate recovery state of the candidate recovery partition is cancelled, the convex ridge partition is restored to output a low-amplitude unloading current to the rear partition, and the partition balanced power formed in the recovery test section is incorporated into the in-band tail quantity.

3. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 1, characterized in that, The rotation process of the main input partition, unloading partition, and tail quantity receiving partition includes: When the leading edge of the power migration crosses the boundary of the adjacent partition, the next partition in the migration direction is determined as the candidate receiving partition, and the current main input partition, unloading partition and tail quantity receiving partition are maintained in their active states. The in-band tail quantity received by the current tail quantity receiving zone is transferred to the candidate receiving zone via a bidirectional transfer branch, and the newly formed zone equalization power during the transfer is continuously incorporated into the in-band tail quantity. After the in-band tail quantity is transferred, the current tail quantity receiving partition is converted into the main input partition, the current main input partition is converted into the unloading partition, and the candidate receiving partition is converted into the new tail quantity receiving partition. Before the in-band tail quantity completes the transfer, when the leading edge of the power migration returns to the adjacent partition boundary it has crossed, the candidate acceptance state of the candidate acceptance partition is cancelled, the transferred in-band tail quantity is sent back to the original tail quantity acceptance partition, and the original partition function state is maintained.

4. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 1, characterized in that, The process for handling the intersection of the new misalignment zone and the previous misalignment zone includes: The overlapping partition of the two misaligned bands is identified as the cross-band transition partition, and the unloaded state of the cross-band transition partition is maintained. The in-band tail of the previous misaligned band enters the crossband transition zone along the original migration direction, and the crossband transition zone is restricted from participating in the main input current of any misaligned band. After the tail quantity within the band of the previous misaligned band enters the non-overlapping partition of the new misaligned band through the cross-band transfer partition, it is merged into the tail quantity within the same band of the new misaligned band, and the non-overlapping partition is determined as the tail quantity receiving partition of the new misaligned band. Before the tail quantity within the previous misaligned band completes the cross-band transfer, when the two misaligned bands change from intersecting to separating, the cross-band transfer stops, the tail quantity within the band that has entered the cross-band transfer partition is returned to the original tail quantity receiving partition of the previous misaligned band, and the two misaligned bands resume partition rotation respectively.

5. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 1, characterized in that, The process for handling the new misalignment band being in the opposite direction to the previous misalignment band includes: The reverse tail quantity formed by the new misalignment band is introduced into the bidirectional transfer branch, forming a counteracting segment with the tail quantity in the original band of the previous misalignment band, and maintaining the function state of the main input partition, unloading partition and tail quantity receiving partition corresponding to the previous misalignment band before the counteracting is completed. When the reverse tail amount is less than the original tail amount, the remaining original tail amount after cancellation is retained in the original tail amount receiving partition, maintaining the original partition rotation direction, and restricting the new misaligned band from starting reverse rotation. When the reverse tail quantity is equal to the original tail quantity, the original tail quantity and the reverse tail quantity cancel each other out, and the opposing cancellation segment ends, maintaining the current partitioning state until the charge migration front crosses the adjacent partition boundary corresponding to the new misalignment band. When the reverse tail quantity is greater than the original tail quantity, the excess portion is determined as the reverse residual tail quantity and transferred to the partition behind the new misalignment band; after the reverse residual tail quantity is transferred and the previous misalignment band is closed, the rotation direction of the main input partition, the unloading partition and the tail quantity receiving partition is reversed.

6. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 1, characterized in that, The process of obtaining the ridge reference segment, the contact unloading leading edge segment, and the charge migration leading edge segment includes: Obtain the surface height sequence of the electrode along the ridge partition and the arrangement direction of two adjacent partitions, determine the interval that is continuously higher than the adjacent positions on both sides as the ridge interval, and determine the partition position corresponding to the ridge interval as the ridge reference segment; After the first input segment ends, according to the thickness reduction order of the ridge partition and the two adjacent partitions, the boundary between the partition that has continuously completed the thickness reduction along the reduction direction and the partition that has not yet completed the thickness reduction is determined as the contact unloading front edge segment. Obtain the partition equalization current between adjacent partitions, accumulate the migrated power in each partition according to the flow direction of the partition equalization current, and determine the partition boundary where the power transfer across partitions is finally completed along the migration direction as the leading edge segment of power migration.

7. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 1, characterized in that, The process of unloading the two misaligned bands in a zone-by-zone manner after separation includes: Starting from the end of the previous misalignment zone, the judgment is performed zone by zone according to the order in which each zone is removed from the previous misalignment zone. When a certain partition is completely removed from the previous misalignment band and the new misalignment band, and the in-band tail quantity in that partition has been transferred to the adjacent partition, the low-amplitude unloading current output by that partition is released, and that partition participates in the common input. If the current partition has not yet escaped any misalignment zone, or if the in-band tail quantity within the partition has not yet been transferred, suspend the release of the partition and its subsequent partitions. When the first two misaligned bands intersect again after the area-by-area removal is completed, the subsequent removal is stopped, so that the unremoved sections continue to be unloaded, and the sections that have been removed but have re-entered the misaligned band resume outputting a low-amplitude unloading current, and the sections are incorporated into the re-merged misaligned band.

8. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 1, characterized in that, The process of determining the closure of the springback migration misalignment zone includes: When the contact unloading leading edge segment coincides with the charge migration leading edge segment, it is determined whether there is any in-band tail quantity in the rebound migration misalignment band that has not yet completed cross-regional transfer. When the two leading edge segments overlap and there is no in-band tail quantity that has not yet completed cross-regional transfer, the rebound migration misalignment zone is determined to be closed. When two leading edge segments overlap, but there are still in-band tail quantities that have not yet completed cross-regional transfer, the transfer direction of the current tail quantity receiving zone and bidirectional transfer branch is maintained until the in-band tail quantity completes cross-regional transfer, and then the rebound migration misalignment zone is closed. When the two leading edge segments of the in-band tail quantity separate again before the cross-regional transfer is completed, the rebound migration misalignment zone is re-determined based on the two leading edge segments after the re-separation, and the in-band tail quantity that has not yet completed the cross-regional transfer is incorporated into the re-determined rebound migration misalignment zone.

9. The lithium plating suppression process for lithium-ion batteries based on dynamic current modulation according to claim 4, characterized in that, The process of transferring the in-band tail quantity across bands via the crossband transfer partition includes: Establish connectivity between the original tail quantity receiving partition of the previous misalignment zone and the cross-band transfer partition, as well as connectivity between the cross-band transfer partition and the non-overlapping partition of the new misalignment zone, to form a directional continuation path along the original migration direction. After all the tail quantities within the band leave the original tail quantity receiving partition, the connection between the original tail quantity receiving partition and the cross-band transfer partition is disconnected, while the connection between the cross-band transfer partition and the non-overlapping partition is maintained until all the tail quantities within the band enter the non-overlapping partition. Before all the tail quantities in the band enter the non-overlapping partition, when the two misaligned bands change from intersecting to separating, the reverse guide is opened to the directional continuation path, and the tail quantities in the band that have entered the non-overlapping partition and the cross-band transfer partition are returned to the original tail quantity receiving partition in sequence. After the cross-band transfer or return is completed, the connection formed between the previous misaligned band and the new misaligned band through the cross-band transfer partition is disconnected, and the bidirectional transfer branches within each misaligned band are restored.

10. The lithium-ion battery lithium plating suppression process based on dynamic current modulation according to claim 3, characterized in that, The rotation of the zone's operational state is carried out zone by zone according to the order in which each zone is arranged along the direction of energy migration. The in-band tail quantity is transferred only between adjacent partitions via bidirectional transfer branches. When the in-band tail quantity in the current tail quantity receiving partition has not yet been transferred out, the next partition in the migration direction is not allowed to participate in the subsequent rotation. After the in-band tail quantity completes its transfer to the adjacent partition, the adjacent partition that received the in-band tail quantity is used as the tail quantity receiving partition for subsequent rotation.

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