Formation channel blockage early warning parameter determination and early warning method

Abstract

The invention relates to the technical field of battery manufacturing, in particular to a formation channel blockage early warning parameter determination and early warning method.The parameter determination method comprises the following steps that the maximum pressure difference value moment point between charging curves in the formation process under the condition that a formation channel is completely unblocked and completely blocked is obtained; performing formation experiments under different negative pressure conditions on the formation step where the maximum pressure difference value moment point is located, and obtaining experiment voltages corresponding to the maximum pressure difference value moment point under each negative pressure condition and the state of the formed battery; and determining an early warning voltage at the time point of the maximum voltage difference value based on the battery state and the experimental voltage after formation under each negative pressure condition. The problem that channel non-blockage is recognized as channel blockage or channel blockage is recognized as channel non-blockage due to the fact that battery abnormal formation recognition is inaccurate or too late in the prior art can be solved.

Description

Technical Field

[0001] The present application relates to the field of battery manufacturing technology, and in particular to a method for determining formation channel blockage warning parameters and a warning method. Background Art

[0002] During the formation process, for example, lithium salts in the electrolyte of lithium-ion batteries will deposit and adhere to the wall of the negative pressure pipe due to the presence of some viscous solvents in the electrolyte, eventually leading to complete blockage of the storage position. During the negative pressure formation of the battery, the gas production and exhaust of the battery is not smooth, and eventually the distance between the electrodes in the battery becomes larger due to gas bubbles, and eventually irreversible black spots are formed, which reduces the quality of the battery. Therefore, it is urgent to propose an early warning method for blockage of the formation negative pressure channel, which can warn of blockage in advance before the channel is completely blocked, thereby reducing the production of defective products.

[0003] In the prior art, a variety of different methods are used to predict and confirm the blockage of the formation channel in advance. For example, the time-voltage curve of the formation process in which the formation channel is completely unblocked is used as a standard, a voltage error range value is set, and the formation time-voltage curve in the operation project is compared with the standard time-voltage curve. When the difference between the two exceeds the voltage error range value, it is considered that the formation channel is blocked.

[0004] However, this method of comparing the formation time-voltage curve in the operation process with the standard time-voltage curve may result in inaccurate or late identification of abnormal formation, resulting in the identification of a non-blocked channel as a blocked channel. Summary of the invention

[0005] The present application provides a formation channel blockage warning parameter determination and warning method, which can solve the problem in the prior art that abnormal battery formation is inaccurately identified or identified too late, resulting in the identification of a non-blocked channel as a blocked channel or the identification of a blocked channel as a non-blocked channel.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0007] In one aspect, the present invention provides a method for determining formation channel blockage warning parameters, comprising the following steps:

[0008] Obtaining the maximum voltage difference between the charging curves during the formation process under the conditions of complete unblocking and complete blocking of the formation channel;

[0009] For the formation step where the maximum pressure difference value time point is located, performing formation experiments under different negative pressure conditions, and obtaining the experimental voltage corresponding to the maximum pressure difference value time point under each negative pressure condition and the battery state after formation;

[0010] Based on the battery state after formation under each negative pressure condition and the experimental voltage, the warning voltage at the time point of the maximum pressure difference value is determined.

[0011] In some optional schemes, the forming experiment under different negative pressure conditions is performed on the forming step at the time point of the maximum pressure difference value, including:

[0012] Performing a forming experiment at a first negative pressure that is half of the standard negative pressure condition for normal forming, and obtaining a first experimental voltage corresponding to the time point of the maximum pressure difference value;

[0013] According to whether the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than a set threshold, it is determined to dismantle the battery or continue to adjust the negative pressure value.

[0014] In some optional solutions, determining to dismantle the battery or continue to adjust the negative pressure value according to whether the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than a set threshold value includes:

[0015] When the difference is greater than a set threshold, a formation experiment is performed at a second negative pressure that is half the sum of the standard negative pressure and the first negative pressure, and a second experimental voltage corresponding to the time point of the maximum pressure difference is obtained;

[0016] When the difference between the second experimental voltage and the standard voltage is greater than the set threshold, the formation experiment is performed again with a negative pressure that is half the sum of the current negative pressure and the previous negative pressure until the difference between the current experimental voltage and the standard voltage is less than the set threshold;

[0017] When the difference is less than or equal to the set threshold, the formed battery is disassembled, and the negative pressure adjustment direction is determined according to the abnormal situation of the disassembled battery.

[0018] In some optional solutions, when the difference is less than or equal to a set threshold, disassembling the formed battery and determining the negative pressure adjustment direction according to the abnormal situation includes:

[0019] When there is no abnormality in the disassembled battery, the formation experiment is performed by reducing the negative pressure by the set difference, and the formed battery is disassembled until the disassembled battery is abnormal;

[0020] When an abnormality is found in a disassembled battery, a formation experiment is performed by increasing the negative pressure by a set difference, and the formed battery is disassembled until the battery is normal after disassembly.

[0021] In some optional solutions, the determining of the warning voltage at the time point of the maximum pressure difference value based on the battery state after formation under each negative pressure condition and the experimental voltage includes:

[0022] For a formation experiment in which the negative pressure is reduced by a set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is abnormal after disassembly, the experimental voltage corresponding to the formation experiment before the battery is disassembled abnormally is used as the warning voltage;

[0023] For a formation experiment in which the negative pressure is increased by a set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is normal after disassembly, the experimental voltage corresponding to the first battery disassembly and normal formation experiment is used as the warning voltage.

[0024] In some optional schemes, the step of obtaining the maximum voltage difference between the charging curves in the formation process under the conditions that the formation channel is completely unblocked and completely blocked includes:

[0025] Obtain the normal charging TV curve during the formation process under the condition that the formation channel is completely unblocked;

[0026] Obtain the blocking charge TV curve during the formation process under the condition that the formation channel is completely blocked;

[0027] The voltage values ​​of the normal charging TV curve and the blocked charging TV curve at the same time point are compared to obtain the time point of the maximum voltage difference value.

[0028] In some optional schemes, when the charging curve in the formation process under the conditions of complete unblocked and complete blocked conditions has the same pressure difference in continuous time periods, and the pressure difference is the maximum pressure difference, the starting point of the continuous time period is taken as the time point of the maximum pressure difference value.

[0029] In a second aspect, the present invention further provides a formation channel blockage early warning method, comprising the following steps:

[0030] Setting a warning voltage during the formation process, wherein the warning voltage is obtained based on the above-mentioned formation channel blockage warning parameter determination method;

[0031] Obtaining the voltage corresponding to the time point of the maximum voltage difference value during the formation process;

[0032] Based on the voltage corresponding to the maximum pressure difference value time point and the warning voltage, a warning is issued for the blockage situation of the battery formation process.

[0033] In some optional solutions, the time point of the maximum pressure difference value is used as the end time point of the formation step.

[0034] In some optional schemes, when the voltage corresponding to the maximum voltage difference value time point during the formation process is greater than the warning voltage, the battery formation is terminated.

[0035] Compared with the prior art, the advantages of the present invention are: in this scheme, by obtaining the maximum pressure difference value time point between the charging curves in the formation process under the conditions of complete unblocked and complete blocked formation channels, the monitoring time point of the battery in the deterioration process is more accurate, the data processing is simpler, and there is no need to compare the voltage data in the entire formation process; by obtaining the experimental voltage corresponding to the maximum pressure difference value time point under each negative pressure condition and the battery state after formation; based on the battery state after formation under each negative pressure condition and the experimental voltage, the warning voltage at the maximum pressure difference value time point is determined. The setting of the warning voltage is more accurate, and it can more accurately judge whether the battery formation process is normal. Compared with directly using the standard voltage for warning, the over-killing situation can be avoided. Compared with the method of setting the safety factor, this method can more accurately feedback whether the battery formation process is abnormal, avoiding the situation of missed killing or over-killing. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 Flow chart of a method for determining formation channel blockage warning parameters in an embodiment of the present invention;

[0038] Figure 2 A data graph is produced for the second step of battery formation in an embodiment of the present invention;

[0039] Figure 3 A data graph is made for the fourth step of battery formation in an embodiment of the present invention;

[0040] Figure 4 It is a partial schematic diagram of a data graph made in the fourth step of battery formation in an embodiment of the present invention;

[0041] Figure 5 This is a graph showing the average pressure difference per second in the fourth step of battery formation in an embodiment of the present invention;

[0042] Figure 6 A data graph is made for the sixth step of battery formation in an embodiment of the present invention;

[0043] Figure 7 It is a partial schematic diagram of a data graph made in the sixth step of battery formation in an embodiment of the present invention;

[0044] Figure 8 This is a graph showing the average pressure difference per second in the sixth step of battery formation in an embodiment of the present invention;

[0045] Fig. 9Flow chart of the formation channel blockage early warning method in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0047] like Figure 1 As shown, on the one hand, the present invention provides a method for determining formation channel blockage warning parameters, comprising the following steps:

[0048] S1: Obtain the time point of the maximum voltage difference between the charging curves during the battery formation process under the conditions of complete unblocked and complete blocked formation channels.

[0049] If blockage occurs during the battery formation process, black spots will be generated in the battery, the temperature inside the battery will accelerate, and the voltage will rise slightly faster than a normal battery. Compared with a normal battery, the cut-off voltage set in the process step will be reached earlier. The time point of the maximum voltage difference between the charging curves in the battery formation process under the conditions of complete channel unblocking and complete blockage is used as the monitoring point, which can predict the blockage in advance.

[0050] In some optional embodiments, step S1 includes the following steps:

[0051] S11: Obtain the normal charging TV curve during the formation process under the condition that the formation channel is completely unobstructed.

[0052] In this example, the standard negative pressure is used when the formation channel is completely unobstructed, and the battery is formed under the condition that the formation channel is completely unobstructed at the standard negative pressure. The formation process is CC charging, that is, constant current charging mode, to obtain the normal charging TV curve. The standard negative pressure is the maximum negative pressure in the subsequent formation experiment.

[0053] S12: Obtain the blocking charge TV curve during the formation process under the condition that the formation channel is completely blocked.

[0054] In this example, other battery formation conditions under the condition that the formation channel is completely blocked are completely consistent with other battery formation conditions under the condition that the formation channel is completely unblocked.

[0055] S13: Compare the voltage values ​​of the normal charging TV curve and the blocked charging TV curve at the same time points to obtain the time point of the maximum voltage difference value.

[0056] In this embodiment, when comparing the voltage values ​​of the normal charging TV curve and the blocked charging TV curve at the same time point, the entire formation process is split according to the formation step, and the normal charging TV curve and the blocked charging TV curve of each formation step are checked to obtain the maximum pressure difference value of the normal charging TV curve and the blocked charging TV curve in each formation step, and then the maximum pressure difference value in each pressure difference step is taken out, and the time point corresponding to the maximum pressure difference value is the maximum pressure difference value time point. After dividing the steps, the pressure difference is compared to facilitate the screening of the steps corresponding to the maximum pressure difference value time point, so as to prepare for the subsequent formation experiment.

[0057] This method determines the maximum voltage difference value as the monitoring time point, making the monitoring time point of the battery deterioration process more accurate and data processing simpler, without the need to compare the voltage data of the entire formation process.

[0058] For example, taking the eight-step formation process as an example, the formation process under the conditions of complete channel unblocking and complete channel blocking is as follows:

[0059]

[0060] Among them, battery 1, battery 2, battery 3 and battery 4 are batteries with completely blocked formation channels, and battery 5, battery 6, battery 7 and battery 8 are batteries with completely unblocked formation channels.

[0061] like Figure 2 As shown, according to the data generated according to the second step of formation: the performance of the second step of the battery with 4 blocked formation channels is basically the same as that of the battery with 4 normal formation channels, and there is no variation point.

[0062] like Figure 3 and Figure 4 As shown in the figure, according to the data generated in the fourth step of formation, the battery with four blocked formation channels reaches the voltage platform of 3.25v in advance after the 1400s of charging. The battery with four normal formation channels reaches the voltage platform of 3.25v after the 2000s of charging. It can be found that the battery with blocked formation channels reaches the voltage platform of 3.25v about 600s earlier than the battery with completely unblocked formation channels.

[0063] like Figure 6 and Figure 7 As shown in the figure, according to the data generated in the sixth step of formation, the battery with four blocked formation channels reaches the voltage platform of 3.35V in advance after the 2000s of charging. The battery with four normal formation channels reaches the voltage platform of 3.35V after the 3500s of charging. It can be found that the battery with blocked formation channels reaches the voltage platform of 3.35V about 1500S earlier than the battery with completely unblocked formation channels.

[0064] like Figure 5 and Figure 8 As shown, according to the average pressure difference data graph of the 4th step of battery formation per second and the average pressure difference data graph of the 6th step of battery formation per second, it is found that the maximum average pressure difference per second is 3.5mv, and the identifiable range of the average pressure difference per second of the 6th step of battery formation is 3.5mv is wider. Therefore, the time interval 600S~1100S corresponding to the maximum pressure difference (3.5mv) in the 6th step of battery formation is selected as the maximum pressure difference value time point between the charging curves in the formation process under the conditions of complete unblocking and complete blocking of the formation channel.

[0065] Preferably, when the charging curve in the battery formation process under the conditions of complete unblocking and complete blocking of the formation channel has the same pressure difference in continuous time periods, and the pressure difference is the maximum pressure difference, the starting point of the continuous time period is taken as the time point of the maximum pressure difference value.

[0066] In this example, the 600S to 1100S intervals are the maximum pressure difference intervals. The 600S is selected as the maximum pressure difference value time point and as the later monitoring time point. This can identify the formation anomaly earlier and avoid the situation of identifying it too late.

[0067] S2: Perform formation experiments under different negative pressure conditions for the formation step where the maximum pressure difference value time point is located, and obtain the experimental voltage corresponding to the maximum pressure difference value time point under each negative pressure condition and the battery state after formation.

[0068] In this example, different negative pressure conditions can be achieved by simulating different blockage conditions of the formation channel. The 6th step is selected for the formation experiment. The formation steps before the 6th step all adopt the normal formation process, that is, the formation channel is completely unblocked, and the standard negative pressure condition is adopted for formation. In this example, the negative pressure used for complete unblocking in the previous steps is the same as the standard negative pressure used in this step.

[0069] In order to obtain the monitoring voltage corresponding to the maximum voltage difference value time point more quickly, step S2 adopts the following steps:

[0070] S21: performing a forming experiment at a first negative pressure that is half of the standard negative pressure condition for normal forming, and obtaining a first experimental voltage corresponding to a time point of a maximum pressure difference value.

[0071] Since it is not known before the experiment what negative pressure should be used for the formation experiment before the battery will produce abnormalities during the formation process, a first negative pressure of half the standard negative pressure condition is selected for the first formation experiment. Through the first formation experiment result under the first negative pressure condition, it can be identified whether the negative pressure condition that will produce abnormal formation results is greater than or less than the first negative pressure condition, which is conducive to the planning of subsequent formation experiments. In this way, the negative pressure value corresponding to the abnormal formation can be found more quickly, that is, the corresponding monitoring voltage can be obtained.

[0072] S22: Determine whether to dismantle the battery or continue to adjust the negative pressure value according to whether the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than a set threshold.

[0073] Specifically, it is determined whether the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than a set threshold.

[0074] It is understandable that if a blockage occurs during the battery formation process, black spots will be generated in the battery, the temperature inside the battery will accelerate, and the voltage will rise slightly faster than a normal battery. If the difference between the first experimental voltage and the standard voltage corresponding to the maximum pressure difference value at the time point under the first negative pressure condition is too large, then the battery must have an abnormality at this time, and it can be determined that the battery has an abnormality without disassembling it. The threshold value can be set through the data in the previous experiment or the process flow.

[0075] The standard voltage is the voltage corresponding to the time point when the formation channel is completely unblocked and the pressure difference is the maximum under standard negative pressure conditions.

[0076] S221: When the difference is greater than a set threshold, a formation experiment is performed with a second negative pressure that is half the sum of the standard negative pressure and the first negative pressure to obtain a second experimental voltage corresponding to the time point of the maximum pressure difference.

[0077] When the difference between the second experimental voltage and the standard voltage is greater than the set threshold, the formation experiment is performed again with a negative pressure that is half the sum of the current negative pressure and the previous negative pressure until the difference between the current experimental voltage and the standard voltage is less than the set threshold.

[0078] Based on the above analysis of the difference between the experimental voltage and the standard voltage, when the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than the set threshold, the battery has already become abnormal and the degree of blockage is already serious. Therefore, it is necessary to increase the negative pressure to find the turning point of the battery from the negative pressure that just produces an abnormality to the normal negative pressure to obtain the corresponding voltage.

[0079] Therefore, during the second formation experiment, the negative pressure used is half the sum of the standard negative pressure and the first negative pressure, and then the second experimental voltage corresponding to the maximum pressure difference value is compared with the standard voltage. If the pressure difference is still greater than the set threshold, the negative pressure value is adjusted in the above manner to carry out the next formation experiment until the difference between the current experimental voltage and the standard voltage is less than the set threshold.

[0080] S222: When the difference is less than or equal to the set threshold, the formed battery is disassembled, and the negative pressure adjustment direction is determined according to the abnormal situation of the disassembled battery.

[0081] Specifically, disassemble the formed battery to determine whether there is any abnormality:

[0082] A: When there is no abnormality in the disassembled battery, the formation experiment is performed by reducing the negative pressure by the set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is abnormal after disassembly.

[0083] B: When an abnormality is found in the disassembled battery, the negative pressure is increased by the set difference based on the current experimental negative pressure to perform a formation experiment, and the formed battery is disassembled until the battery is normal after disassembly.

[0084] Based on the above analysis on the difference between the experimental voltage and the standard voltage, when the voltage difference between the experimental voltage and the standard voltage is less than or equal to the set threshold, it is impossible to identify whether the battery formed under negative pressure conditions has an abnormality, so it needs to be disassembled for confirmation.

[0085] The current experimental negative pressure is the experimental negative pressure corresponding to when the difference between the current experimental voltage and the standard voltage is less than the set threshold.

[0086] When the difference between the experimental voltage and the standard voltage is less than or equal to the set threshold, the battery after disassembly and formation is normal, which means that the negative pressure value corresponding to the simulated blockage at this time is not enough to cause the battery to become abnormal. Therefore, the negative pressure value needs to be reduced until the negative pressure value corresponding to the abnormal battery after disassembly is found.

[0087] When the difference between the experimental voltage and the standard voltage is less than or equal to the set threshold, the disassembled battery is abnormal, which means that the negative pressure value at this time corresponds to the simulated blockage and has caused the battery to become abnormal. Therefore, the negative pressure value can be increased until the negative pressure value corresponding to the normal disassembled battery is found.

[0088] Through the above method, the turning point between the battery just producing abnormal negative pressure and normal negative pressure in the negative pressure simulation blockage experiment can be quickly found, or the turning point between the battery normal and just producing abnormal negative pressure can be found to obtain the experimental voltage corresponding to the time point of the maximum pressure difference value.

[0089] S3: Based on the battery status after formation under each negative pressure condition and the experimental voltage, determine the warning voltage at the time point of the maximum pressure difference value.

[0090] Based on the above experiments, the battery status after formation under various negative pressure conditions and the experimental voltage corresponding to the time point of the maximum pressure difference value are obtained. At this time, it is necessary to determine the voltage corresponding to the normal performance of the battery when it is disassembled as the warning voltage.

[0091] Step S3 includes the following steps:

[0092] S31: For a formation experiment based on the current experimental negative pressure, the negative pressure is reduced by a set difference, and the formed battery is disassembled until the battery is abnormal after disassembly, and the experimental voltage corresponding to the formation experiment before the battery is disassembled abnormally is used as the warning voltage.

[0093] For a formation experiment in which there is no abnormality in the disassembled battery, the formation experiment is performed by reducing the negative pressure by a set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is abnormal after disassembly. The experimental voltage corresponding to the formation experiment before the battery is disassembled abnormally corresponds to the experimental condition that can just enable normal formation. Therefore, selecting the corresponding experimental voltage at this time as the warning voltage can more accurately warn whether the formation is abnormal.

[0094] S32: For a formation experiment based on the current experimental negative pressure, the negative pressure is increased by a set difference, and the formed battery is disassembled until the disassembled battery is normal, the experimental voltage corresponding to the first battery disassembly and normal formation experiment is used as the warning voltage.

[0095] For abnormal formation experiments in disassembled batteries, the formation experiment is performed by increasing the negative pressure by a set difference based on the current experimental negative pressure, and the formed batteries are disassembled until the disassembled batteries are normal. The experimental voltage corresponding to the normal formation experiment of the first battery disassembly corresponds to the experimental conditions that can just enable normal formation. Therefore, selecting the corresponding experimental voltage at this time as the warning voltage can more accurately warn whether the formation is abnormal.

[0096] In this example, the setting difference is determined according to actual conditions or experience; the standard negative pressure value is -70kpa, which can be set according to actual conditions.

[0097] According to the above step S1, the standard voltage is 3.2V. According to the above method, it is finally confirmed that the early warning voltage corresponding to the maximum differential pressure value time point 600S is 3.25V, which can more accurately judge whether the battery formation process is normal. Compared with directly using the standard voltage for early warning, the overkill situation can be avoided, that is, the battery that is normally formed is identified as a battery that is abnormally formed; compared with the method of setting the safety factor, this method can more accurately feedback whether the battery formation process is abnormal, avoid the situation of missing or overkill, and set the safety factor based on the standard voltage. If the safety factor is set too small, that is, the early warning voltage is set too low, it is easy to identify the battery that is normally formed as a battery that is abnormally formed; if the safety factor is set too large, that is, the early warning voltage is set too large, it is easy to identify the battery that is abnormally formed as a battery that is normally formed. In addition, compared with using the standard TV in the entire formation process as the monitoring basis, this scheme only uses the voltage data corresponding to the maximum differential pressure value time point to monitor, which can save the data processing amount.

[0098] like Fig. 9 As shown, in the second aspect, a formation channel blockage early warning method comprises the following steps:

[0099] S10: Setting a warning voltage during the formation process, wherein the warning voltage is obtained based on any of the above-mentioned methods for determining warning parameters of formation channel blockage.

[0100] In this example, according to the maximum pressure difference value time point obtained in the above formation channel blockage warning parameter determination method, the warning voltage during the formation process is set, which can more accurately determine whether the battery formation process is normal.

[0101] S20: Obtaining the voltage corresponding to the time point of the maximum voltage difference value during the formation process.

[0102] Preferably, the maximum differential pressure value time point is used as the end time point of the formation step. When the formation channel blockage in the formation process is warned, only the voltage at the end of the formation step, i.e. the voltage corresponding to the maximum differential pressure value time point, is obtained, and the voltage in the entire formation process does not need to be obtained, which can reduce the amount of data processing.

[0103] For example, the maximum pressure difference time point determined in the aforementioned formation channel blockage warning parameter determination method is located at 600S in the 6th formation step. In normal production formation operations, the maximum pressure difference time point is used as the end time point of the 6th formation step, that is, the 6th formation step is designed to be 600S.

[0104] S30: Based on the voltage corresponding to the maximum pressure difference value time point and the warning voltage, a warning is issued for the blockage situation of the battery formation process.

[0105] Preferably, when the voltage corresponding to the maximum voltage difference value point in the formation process is greater than the warning voltage, the battery formation is terminated.

[0106] When the voltage corresponding to the maximum voltage difference value at the time point during the formation process is greater than the warning voltage, it indicates that the battery has an abnormal condition. Therefore, terminating the battery formation can prevent the battery from further deteriorating in the subsequent formation process.

[0107] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0108] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0109] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0110] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0111] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0112] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method.

[0113] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for determining formation channel blockage warning parameters, characterized in that: The following steps are involved: Obtaining the maximum voltage difference between the charging curves during the formation process under the conditions of complete unblocking and complete blocking of the formation channel; For the formation step where the maximum pressure difference value time point is located, performing formation experiments under different negative pressure conditions, and obtaining the experimental voltage corresponding to the maximum pressure difference value time point under each negative pressure condition and the battery state after formation; Based on the battery state after formation under each negative pressure condition and the experimental voltage, the warning voltage at the time point of the maximum pressure difference value is determined.

2. The method for determining formation channel blockage warning parameters according to claim 1, characterized in that: The forming step at the time point of the maximum pressure difference value is subjected to forming experiments under different negative pressure conditions, including: Performing a forming experiment at a first negative pressure that is half of the standard negative pressure condition for normal forming, and obtaining a first experimental voltage corresponding to the time point of the maximum pressure difference value; According to whether the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than a set threshold, it is determined to dismantle the battery or continue to adjust the negative pressure value.

3. The method for determining formation channel blockage warning parameters according to claim 2, characterized in that: The step of determining whether to dismantle the battery or continue to adjust the negative pressure value according to whether the difference between the first experimental voltage and the standard voltage under the standard negative pressure condition is greater than a set threshold value includes: When the difference is greater than a set threshold, a formation experiment is performed at a second negative pressure that is half the sum of the standard negative pressure and the first negative pressure, and a second experimental voltage corresponding to the time point of the maximum pressure difference is obtained; When the difference between the second experimental voltage and the standard voltage is greater than the set threshold, the formation experiment is performed again with a negative pressure that is half the sum of the current negative pressure and the previous negative pressure until the difference between the current experimental voltage and the standard voltage is less than the set threshold; When the difference is less than or equal to the set threshold, the formed battery is disassembled, and the negative pressure adjustment direction is determined according to the abnormal situation of the disassembled battery.

4. The method for determining formation channel blockage warning parameters according to claim 3, characterized in that: When the difference is less than or equal to the set threshold, the formed battery is disassembled, and the negative pressure adjustment direction is determined according to the abnormal situation, including: When there is no abnormality in the disassembled battery, the formation experiment is performed by reducing the negative pressure by the set difference based on the current experimental negative pressure, and the formed battery is disassembled until the disassembled battery is abnormal; When an abnormality is found in a disassembled battery, a formation experiment is performed by increasing the negative pressure by a set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is normal after disassembly.

5. The method for determining formation channel blockage warning parameters according to claim 4, characterized in that: The method of determining the warning voltage at the time point of the maximum pressure difference value based on the battery state after formation under each negative pressure condition and the experimental voltage includes: For a formation experiment in which the negative pressure is reduced by a set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is abnormal after disassembly, the experimental voltage corresponding to the formation experiment before the battery is disassembled abnormally is used as the warning voltage; For a formation experiment in which the negative pressure is increased by a set difference based on the current experimental negative pressure, and the formed battery is disassembled until the battery is normal after disassembly, the experimental voltage corresponding to the first battery disassembly and normal formation experiment is used as the warning voltage.

6. The method for determining formation channel blockage warning parameters according to claim 1, characterized in that: The time point of obtaining the maximum voltage difference between the charging curves in the formation process under the conditions of complete unblocking and complete blocking of the formation channel includes: Obtain the normal charging TV curve during the formation process under the condition that the formation channel is completely unblocked; Obtain the blocking charge TV curve during the formation process under the condition that the formation channel is completely blocked; The voltage values ​​of the normal charging TV curve and the blocked charging TV curve at the same time point are compared to obtain the time point of the maximum voltage difference value.

7. The method for determining formation channel blockage warning parameters according to claim 1, characterized in that: When the charging curve in the formation process under the conditions of complete unblocking and complete blocking of the formation channel has the same pressure difference in a continuous time period, and the pressure difference is the maximum pressure difference, the starting point of the continuous time period is taken as the time point of the maximum pressure difference value.

8. A formation channel blockage early warning method, characterized in that: The following steps are involved: Setting a warning voltage during the formation process, wherein the warning voltage is obtained based on the method for determining a formation channel blockage warning parameter according to any one of claims 1 to 7; Obtain the voltage corresponding to the time point of the maximum voltage difference value during the formation process; Based on the voltage corresponding to the maximum pressure difference value time point and the warning voltage, a warning is issued for the blockage situation of the battery formation process.

9. The formation channel blockage early warning method according to claim 8, characterized in that: The time point of the maximum pressure difference value is taken as the end time point of the forming step.

10. The formation channel blockage early warning method according to claim 8, characterized in that: When the voltage corresponding to the maximum voltage difference value at the time point during the formation process is greater than the warning voltage, the battery formation is terminated.

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