Charging and discharging control system of high-silicon negative electrode battery electrolyte

Abstract

The invention relates to the field of lithium ion batteries, in particular to a high-silicon negative electrode battery electrolyte charging and discharging control system which comprises a high-silicon negative electrode battery, a detection module, a data processing module and an adjustment control module. By collecting the resistance and temperature of the SEI film on the surface of the high-silicon negative electrode battery and the concentration of the electrolyte additive in real time, comprehensive monitoring of the charging and discharging process of the battery is achieved, through multi-stage judgment of the data processing module, the electrolyte state of the high-silicon negative electrode battery in the charging and discharging process is effectively managed, the charging and discharging efficiency is improved, and the battery quality is improved. According to the method, parameters can be automatically adjusted according to different working conditions, the adaptability is high, the application range is wide, charging and discharging currents are intelligently adjusted by monitoring the state of the SEI film, a proper SEI film is controlled to be formed, and the service life of the battery is effectively prolonged by predicting additive consumption and supplementing additives in time, so that the high-silicon negative electrode battery works in the optimal state.

Description

Technical Field

[0001] The invention relates to the field of lithium-ion batteries, and in particular to a charge and discharge control system for an electrolyte of a high-silicon negative electrode battery. Background Art

[0002] With the rapid development of electric vehicles and portable electronic devices, the demand for high energy density batteries is growing. High silicon anode batteries have become a research hotspot because of their theoretical capacity of up to 3579mAh / g, which is nearly 10 times that of traditional graphite anodes (372mAh / g). However, high silicon anodes have serious volume expansion problems during the charge and discharge process, which can reach more than 300%, resulting in damage to the electrode structure and shedding of active materials, which in turn causes rapid capacity decay.

[0003] To solve this problem, researchers have developed various electrolyte additives, such as fluoroethylene carbonate (FEC) and ethylene carbonate (VC), to form a stable solid electrolyte interface (SEI) film. However, these additives are gradually consumed during the cycle and affect the long-term performance of the battery. In addition, the formation process of the SEI film also needs to be precisely controlled. If it is too thin, it will lead to insufficient protection, and if it is too thick, it will increase the internal resistance of the battery.

[0004] Traditional battery electrolyte management systems mainly focus on the control of voltage, current and temperature, and have limited management of electrolyte composition changes and SEI film formation process. Therefore, developing an intelligent control system that can comprehensively consider electrolyte composition changes, SEI film formation dynamics and charging and discharging parameters is of great significance to improving the performance and life of high-silicon negative electrode batteries.

[0005] The patent document with Chinese patent publication number CN107959038A discloses a pulse charging and discharging system and method for liquid flow batteries that improves the utilization rate of electrolytes, and belongs to the field of new energy storage. An intermittently disconnected pulse signal is input to the pulse timing power switch, so that the charging and discharging system no longer continuously charges the electrolyte in the liquid flow battery, but instead switches to intermittent charging. During the non-charging period, the circulation pump continues to run until the charging cut-off voltage is reached, completing the charging process and entering the discharging process. During the discharging process, the pulse timing power switch is also intermittently disconnected to keep the electrolyte intermittently discharged until the discharge cut-off voltage is reached to complete the discharging process. This constitutes a charging and discharging cycle.

[0006] It can be seen that in the existing technology, it is impossible to effectively manage the changes in electrolyte composition and SEI film formation in high-silicon negative electrode batteries, resulting in insufficient battery performance and life. Summary of the invention

[0007] To this end, the present invention provides a charge and discharge control system for a high-silicon negative electrode battery electrolyte, so as to overcome the technical problem in the prior art that the changes in the electrolyte composition of the high-silicon negative electrode battery and the formation of the SEI film cannot be effectively managed, resulting in insufficient battery performance and life.

[0008] To achieve the above object, the present invention provides a charge and discharge control system for a high-silicon negative electrode battery electrolyte, the system comprising:

[0009] A high silicon negative electrode battery, comprising a high silicon negative electrode, an electrolyte and an additive, wherein the electrolyte forms a SEI film on the surface of the high silicon negative electrode under the action of the additive during the charge and discharge process;

[0010] A detection module, which is connected to the high-silicon negative electrode battery and is used to detect the real-time temperature of the high-silicon negative electrode battery during the charging and discharging process, the real-time resistance of the SEI film, and the real-time concentration of the additive;

[0011] a data processing module connected to the detection module, for determining whether the SEI film state is good or not according to the real-time resistance in a resistance threshold interval formed by a minimum SEI film resistance threshold and a maximum SEI film resistance threshold when the real-time temperature meets a preset temperature threshold range, so as to obtain a determination result;

[0012] An adjustment control module, connected to the high-silicon negative electrode battery pack and the data processing module, for adjusting the temperature when the real-time temperature does not meet the preset temperature threshold range;

[0013] When the determination result is that the SEI film state is poor, adjusting the charge and discharge current according to the relationship between the real-time resistance and the minimum SEI film resistance threshold or the maximum SEI film resistance threshold;

[0014] And, when the judgment result is that the SEI film is in good condition, the real-time consumption rate is calculated according to the real-time concentration, the charge and discharge consumption of the additive is predicted according to the real-time consumption rate, and the addition amount is determined based on the charge and discharge consumption.

[0015] Furthermore, the data processing module includes:

[0016] A first determination unit, configured to determine whether the temperature is abnormal according to the real-time temperature;

[0017] The second determination unit is connected to the first determination unit and is used to determine whether the SEI film is in a good state according to the real-time resistance.

[0018] Furthermore, the first determination unit includes a first setting subunit, a first comparing subunit and a first determination subunit, wherein:

[0019] The first setting subunit is used to set the maximum charge and discharge temperature and the minimum charge and discharge temperature;

[0020] The first comparison subunit is connected to the first setting subunit, and is used to compare the real-time temperature with the highest charge and discharge temperature and the lowest charge and discharge temperature to obtain a comparison result;

[0021] The first determination subunit is connected to the first comparison subunit and is used to determine whether the temperature is abnormal according to the comparison result.

[0022] Further, the first sub-determination unit determines that the temperature is abnormal when the real-time temperature is greater than the maximum charge and discharge temperature or less than the minimum charge and discharge temperature;

[0023] The first determination subunit determines that the temperature is normal when the real-time temperature is neither less than the lowest charge and discharge temperature nor greater than the highest charge and discharge temperature.

[0024] Furthermore, the second determination unit includes a second setting subunit, a second comparison subunit and a second determination subunit, wherein:

[0025] The second setting subunit is used to set a minimum SEI film resistance threshold and a maximum SEI film resistance threshold;

[0026] The second comparison subunit is used to compare the real-time resistance with the resistance threshold range to determine whether the charge and discharge current of the high-silicon negative electrode battery needs to be changed;

[0027] If the SEI film resistance is less than the minimum SEI film resistance threshold, the second determination unit determines that the SEI film state is poor;

[0028] If the SEI film resistance is greater than the maximum SEI film resistance threshold, the second determination unit determines that the SEI film state is poor;

[0029] If the SEI film resistance is neither less than the minimum SEI film resistance threshold nor greater than the maximum SEI film resistance threshold, the second determination unit determines that the SEI film is in good condition.

[0030] Furthermore, when the first determination unit determines that the temperature is abnormal, the adjustment control module adjusts the temperature according to the real-time temperature.

[0031] When the real-time temperature is lower than the lowest preset temperature, the temperature is increased and adjusted according to the difference between the real-time temperature and the highest preset temperature;

[0032] When the real-time temperature is greater than the highest preset temperature, the temperature is adjusted to be lowered according to the difference between the real-time temperature and the lowest preset temperature.

[0033] Further, when the second determination unit determines that the SEI film state is poor, the adjustment control module adjusts the charge and discharge current according to the relationship between the real-time resistance and the minimum SEI film resistance threshold and the maximum SEI film resistance threshold,

[0034] When the SEI membrane resistance is less than the minimum SEI membrane resistance threshold, the charge and discharge current is adjusted by a fixed increment until the real-time resistance is within the resistance threshold interval;

[0035] When the SEI film resistance is greater than the minimum SEI film resistance threshold, the charge and discharge current is adjusted to a fixed decrement until the real-time resistance is within the resistance threshold interval.

[0036] Further, when the second determination unit determines that the SEI film is in good condition, the adjustment control module predicts the additive consumption according to the real-time consumption rate, and determines the additive replenishment amount based on the additive consumption.

[0037] Furthermore, the detection module includes:

[0038] A first detection unit, which is used to detect the temperature of the high-silicon negative electrode battery during the charging and discharging process to obtain the real-time temperature;

[0039] The second detection unit is used to detect the real-time resistance of the SEI film.

[0040] Furthermore, the detection module also includes a third detection unit, which is used to detect the concentration of the additive in the electrolyte to obtain the real-time concentration of the additive.

[0041] Compared with the prior art, the beneficial effect of the present invention lies in that, by real-time detection of the resistance, temperature and concentration of the SEI film on the surface of the high-silicon negative electrode battery, the electrolyte additive concentration can be fully monitored to achieve the battery charge and discharge process. After multi-level determination by the data processing module, the electrolyte state of the high-silicon negative electrode battery during the charge and discharge process can be effectively managed to improve the charge and discharge efficiency. The parameters can be automatically adjusted according to different working conditions. The adaptability is strong and the application range is wide. The charge and discharge current can be intelligently adjusted by monitoring the SEI film state to control the formation of a suitable SEI film. By predicting the consumption of additives and replenishing them in time, the high-silicon negative electrode battery can work in the best state, which effectively extends the battery life.

[0042] Furthermore, by real-time monitoring of battery temperature and SEI film status, a comprehensive evaluation of the battery working status is achieved, and the battery operating status is effectively obtained.

[0043] Furthermore, through continuous detection and determination of battery temperature, precise supervision of battery temperature is achieved, which can accurately identify whether the temperature is abnormal and effectively prevent potential safety hazards caused by excessively high or low temperatures. Automated temperature monitoring reduces human intervention, improves system reliability, and provides valuable data support for subsequent battery management optimization.

[0044] Furthermore, through real-time detection of SEI membrane resistance, the system can promptly detect changes in the SEI membrane state. This real-time monitoring mechanism provides a basis for dynamically adjusting the charge and discharge current, helps evaluate the state of the SEI membrane, and provides a basis for subsequent control strategies, thereby extending the battery life.

[0045] Furthermore, by making precise adjustments according to specific circumstances when temperature anomalies are detected, it is ensured that the battery always operates within the optimal temperature range. By making adjustments based on the difference between the real-time temperature and the preset temperature range, a suitable operating temperature can be maintained, which is beneficial to significantly improve the battery's charging and discharging efficiency, extend battery life, and reduce safety risks.

[0046] Furthermore, through the real-time changes in the SEI film resistance, the system can dynamically adjust the charge and discharge current, achieve continuous optimization of the charge and discharge process, and improve the charge and discharge efficiency and stability of the battery. By adjusting the charge and discharge current and maintaining the ideal state of the SEI film, the electrolyte decomposition and side reactions can be effectively reduced, the overall performance of the battery can be comprehensively improved, the battery capacity decay rate can be reduced, and the battery service life can be significantly extended.

[0047] Furthermore, through real-time monitoring and prediction, the system can accurately estimate the consumption of additives, thereby achieving precise replenishment, avoiding over- or under-supply, and maintaining the optimal performance of the electrolyte. Accurate additive management can reduce waste and lower battery maintenance costs, while improving overall economic benefits by extending battery life.

[0048] Furthermore, by detecting temperature and SEI film resistance, the system can fully grasp the working status of high-silicon negative electrode batteries, providing a solid foundation for precise control. Continuous real-time detection enables the system to capture subtle changes in battery status in a timely manner, achieve rapid response and adjustment, and effectively prevent potential problems. It is suitable for different working conditions and charging and discharging strategies, enhancing the flexibility and adaptability of the system.

[0049] Furthermore, specifically, by detecting the concentration of additives in real time, the system can accurately grasp the state of the electrolyte and the consumption of additives, which helps to replenish them in time to prevent a sharp decline in battery performance or safety hazards caused by the depletion of additives, maintain the optimal performance of the electrolyte, and thus extend the service life of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a system framework diagram of a charge and discharge control system for a high-silicon negative electrode battery electrolyte according to an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of the structure of a data processing module according to an embodiment of the present invention;

[0052] Figure 3 is a schematic diagram of the structure of a first determination unit according to an embodiment of the present invention;

[0053] Figure 4 Schematic diagram of the structure of the second determination unit in an embodiment of the present invention

[0054] Figure 5 Schematic diagram of the structure of the detection module according to the embodiment of the present invention. DETAILED DESCRIPTION

[0055] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0056] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0057] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0058] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] See also Figure 1 ,like Figure 1 As shown, it is a system block diagram of a charge and discharge control system for a high-silicon negative electrode battery electrolyte according to an embodiment of the present invention;

[0060] Specifically, an embodiment of the present invention provides a charge and discharge control system for a high-silicon negative electrode battery electrolyte, comprising:

[0061] A high silicon negative electrode battery, comprising a high silicon negative electrode, an electrolyte and an additive, wherein the electrolyte forms a SEI film on the surface of the high silicon negative electrode under the action of the additive during the charge and discharge process;

[0062] A detection module, which is connected to the high-silicon negative electrode battery and is used to detect the real-time temperature of the high-silicon negative electrode battery during the charging and discharging process, the real-time resistance of the SEI film, and the real-time concentration of the additive;

[0063] a data processing module connected to the detection module, for determining whether the SEI film state is good or not according to the real-time resistance in a resistance threshold interval formed by a minimum SEI film resistance threshold and a maximum SEI film resistance threshold when the real-time temperature meets a preset temperature threshold range, so as to obtain a determination result;

[0064] An adjustment control module, connected to the high-silicon negative electrode battery pack and the data processing module, for adjusting the temperature when the real-time temperature does not meet the preset temperature threshold range;

[0065] When the determination result is that the SEI film state is poor, adjusting the charge and discharge current according to the relationship between the real-time resistance and the minimum SEI film resistance threshold or the maximum SEI film resistance threshold;

[0066] And, when the judgment result is that the SEI film is in good condition, the real-time consumption rate is calculated according to the real-time concentration, the charge and discharge consumption of the additive is predicted according to the real-time consumption rate, and the addition amount is determined based on the charge and discharge consumption.

[0067] Specifically, the SEI film is a protective film formed on the surface of the negative electrode when the battery is charged and discharged for the first time. The resistance of the SEI film reflects its state and has an important influence on the battery performance. The resistance of the SEI film can be measured by electrochemical impedance spectroscopy. Additives may include fluoroethylene carbonate (FEC), ethylene carbonate (VC), etc., which are not specifically limited here.

[0068] Specifically, by real-time detection of the resistance, temperature and concentration of the SEI film on the surface of the high-silicon negative electrode battery, the battery charging and discharging process is fully monitored. After multi-level judgment by the data processing module, the electrolyte state of the high-silicon negative electrode battery during the charging and discharging process is effectively managed to improve the charging and discharging efficiency. The parameters can be automatically adjusted according to different working conditions. It has strong adaptability and a wide range of applications. By monitoring the state of the SEI film, the charging and discharging current is intelligently adjusted to control the formation of a suitable SEI film. By predicting the consumption of additives and replenishing them in time, the high-silicon negative electrode battery works in the best state, effectively extending the battery life.

[0069] Please continue reading Figure 2 ,like Figure 2 As shown, it is a structural diagram of a data processing module according to an embodiment of the present invention;

[0070] Specifically, the data processing module includes:

[0071] A first determination unit, configured to determine whether the temperature is abnormal according to the real-time temperature;

[0072] The second determination unit is connected to the first determination unit and is used to determine whether the SEI film is in a good state according to the real-time resistance.

[0073] In this embodiment, the data processing module can make a comprehensive judgment on the battery temperature and the SEI film state through the cooperation of the first judgment unit and the second judgment unit, thereby providing a basis for subsequent adjustment and control.

[0074] Specifically, by real-time monitoring of battery temperature and SEI film status, a comprehensive evaluation of the battery working status is achieved, and the battery operating status is effectively obtained.

[0075] Please continue reading Figure 3 ,like Figure 3 As shown, it is a schematic diagram of the structure of the first determination unit in an embodiment of the present invention;

[0076] Specifically, the first determination unit includes a first setting subunit, a first comparing subunit and a first determination subunit, wherein:

[0077] The first setting subunit is used to set the maximum charge and discharge temperature and the minimum charge and discharge temperature;

[0078] The first comparison subunit is connected to the first setting subunit, and is used to compare the real-time temperature with the highest charge and discharge temperature and the lowest charge and discharge temperature to obtain a comparison result;

[0079] The first determination subunit is connected to the first comparison subunit and is used to determine whether the temperature is abnormal according to the comparison result.

[0080] Specifically, the maximum charge and discharge temperature and the minimum charge and discharge temperature are the maximum and minimum temperatures allowed during the battery charge and discharge process, which are set according to the performance of the high-silicon negative electrode battery and the usage environment, and the real-time temperature is the current battery temperature detected by the detection module.

[0081] Specifically, the first sub-determination unit determines that the temperature is abnormal when the real-time temperature is greater than the maximum charge and discharge temperature or less than the minimum charge and discharge temperature;

[0082] The first determination subunit determines that the temperature is normal when the real-time temperature is neither less than the lowest charge and discharge temperature nor greater than the highest charge and discharge temperature.

[0083] During the specific implementation process, the high-silicon negative electrode battery has a preset minimum charge and discharge temperature Tmin=10°C and a preset maximum charge and discharge temperature Tmax=40°C. The detection module detects the current real-time temperature T=45°C. The first judgment unit compares the real-time temperature with the preset minimum charge and discharge temperature and the preset maximum charge and discharge temperature. Since T=45°C>Tmax=40°C, it is determined that the temperature is abnormal at this time.

[0084] Specifically, through continuous detection and determination of battery temperature, precise supervision of battery temperature is achieved, which can accurately identify whether the temperature is abnormal and effectively prevent potential safety hazards caused by excessively high or low temperatures. Automated temperature monitoring reduces human intervention, improves system reliability, and provides valuable data support for subsequent battery management optimization.

[0085] Please continue reading Figure 4 ,like Figure 4 As shown, it is a schematic diagram of the structure of the second determination unit in an embodiment of the present invention;

[0086] Specifically, the second determination unit includes a second setting subunit, a second comparison subunit and a second determination subunit, wherein:

[0087] The second setting subunit is used to set a minimum SEI film resistance threshold and a maximum SEI film resistance threshold;

[0088] The second comparison subunit is used to compare the real-time resistance with the resistance threshold range to determine whether the charge and discharge current of the high-silicon negative electrode battery needs to be changed;

[0089] If the SEI film resistance is less than the minimum SEI film resistance threshold, the second determination unit determines that the SEI film state is poor;

[0090] If the SEI film resistance is greater than the maximum SEI film resistance threshold, the second determination unit determines that the SEI film state is poor;

[0091] If the SEI film resistance is neither less than the minimum SEI film resistance threshold nor greater than the maximum SEI film resistance threshold, the second determination unit determines that the SEI film is in good condition.

[0092] Specifically, according to the electrochemical principle, the resistance of the SEI film is closely related to its thickness and structure. A thin SEI film (too small resistance) may lead to insufficient protection, while a thick SEI film (too large resistance) may hinder the transmission of lithium ions. Therefore, a suitable SEI film resistance range is crucial to battery performance. The SEI film resistance is obtained by using electrochemical impedance spectroscopy technology. In the specific implementation process, the SEI film resistance of the high-silicon negative electrode battery is in the ideal range of the second determination unit, with a preset minimum SEI film resistance threshold Rmin=100Ω and a maximum SEI film resistance threshold Rmax=500Ω. When the first determination unit measures the real-time SEI film resistance R=80Ω when the real-time temperature is normally within the appropriate range, the second determination unit compares the real-time SEI film resistance R=80Ω with the minimum SEI film resistance threshold Rmin=100Ω and the maximum SEI film resistance threshold Rmax=500Ω. Since the real-time SEI film resistance R=80Ω is less than the minimum SEI film resistance threshold Rmin=100Ω, the second determination unit determines that the SEI film state is poor.

[0093] Specifically, through real-time detection of SEI membrane resistance, the system can promptly detect changes in the SEI membrane state. This real-time monitoring mechanism provides a basis for dynamically adjusting the charge and discharge current, helps evaluate the state of the SEI membrane, and provides a basis for subsequent control strategies, thereby extending the battery life.

[0094] Specifically, when the first determination unit determines that the temperature is abnormal, the adjustment control module adjusts the temperature according to the real-time temperature.

[0095] When the real-time temperature is lower than the lowest preset temperature, the temperature is increased and adjusted according to the difference between the real-time temperature and the highest preset temperature;

[0096] When the real-time temperature is greater than the highest preset temperature, the temperature is adjusted to be lowered according to the difference between the real-time temperature and the lowest preset temperature.

[0097] During the specific implementation process, the preset minimum charge and discharge temperature Tmin=10°C, the preset maximum charge and discharge temperature Tmax=40°C, the real-time temperature when the temperature is abnormal is T=45°C, T=45°C is greater than Tmax=40°C, then the temperature is lowered and adjusted according to the difference between the real-time temperature and the minimum preset temperature △T=T-Tmin=35°C, that is, the temperature is lowered by 35°C.

[0098] Specifically, by making precise adjustments based on specific circumstances when temperature abnormalities are detected, we ensure that the battery always operates within the optimal temperature range. By making adjustments based on the difference between the real-time temperature and the preset temperature range, we can maintain a suitable operating temperature, which is beneficial to significantly improve the battery's charging and discharging efficiency, extend battery life, and reduce safety risks.

[0099] Specifically, when the second determination unit determines that the SEI film state is poor, the adjustment control module adjusts the charge and discharge current according to the relationship between the real-time resistance and the minimum SEI film resistance threshold and the maximum SEI film resistance threshold,

[0100] When the SEI membrane resistance is less than the minimum SEI membrane resistance threshold, the charge and discharge current is adjusted by a fixed increment until the real-time resistance is within the resistance threshold interval;

[0101] When the SEI film resistance is greater than the minimum SEI film resistance threshold, the charge and discharge current is adjusted to a fixed decrement until the real-time resistance is within the resistance threshold interval.

[0102] During the specific implementation process, the fixed increment and fixed decrement of current are both adjusted by 0.1A every five minutes, the initial charge and discharge current I0=3A, the preset minimum SEI membrane resistance threshold Rmin=100Ω, the maximum SEI membrane resistance threshold Rmax=500Ω, and the real-time SEI membrane resistance R=80Ω is less than the minimum SEI membrane resistance threshold. The initial charge and discharge current I0=3A is adjusted by increasing by 0.1A every five minutes until the real-time resistance ends the adjustment within the resistance threshold range.

[0103] Specifically, through the real-time changes in the SEI film resistance, the system can dynamically adjust the charge and discharge current, achieve continuous optimization of the charge and discharge process, and improve the charge and discharge efficiency and stability of the battery. By adjusting the charge and discharge current and maintaining the ideal state of the SEI film, it can effectively reduce electrolyte decomposition and side reactions, comprehensively improve the overall performance of the battery, reduce the battery capacity decay rate, and significantly extend the battery life.

[0104] Specifically, when the second determination unit determines that the SEI film is in a good state, the adjustment control module predicts the additive consumption according to the real-time consumption rate, and determines the additive replenishment amount based on the additive consumption.

[0105] Specifically, the conductivity sensor is used to measure the electrolyte concentration once an hour, C(t) represents the real-time electrolyte concentration at time t, and the additive concentration change rate V=ΔC / Δt=C(t)-C(t-1) / 1 hour, wherein: ΔC represents the electrolyte concentration change amount C(t) is the electrolyte concentration at the current moment, C(t-1) is the electrolyte concentration 1 hour ago, in the specific implementation process, the preset additive concentration change rate threshold V0=0.5 mol / L / hour, the current detected real-time electrolyte concentration C(t)=1.5 mol / L, the electrolyte concentration 1 hour ago C(t-1)=1.2 mol / L, then the real-time additive concentration consumption rate V=ΔC / Δt=(1.5 mol / L-1.2 mol / L) / 1 hour=0.3 mol / L / hour, and the predicted electrolyte concentration consumption after 4 hours of charge and discharge time is 4×0.3=1.2 mol l / L, the amount of additive added is to increase the electrolyte concentration by 1.2 mol / L.

[0106] Specifically, through real-time monitoring and prediction, the system can accurately estimate the consumption of additives, thereby achieving precise replenishment, avoiding over- or under-supply, and maintaining the optimal performance of the electrolyte. Accurate additive management can reduce waste and lower battery maintenance costs, while improving overall economic benefits by extending battery life.

[0107] Please continue reading Figure 5 ,like Figure 5 As shown, it is a schematic diagram of the structure of the detection module according to an embodiment of the present invention;

[0108] Specifically, the detection module includes:

[0109] A first detection unit, which is used to detect the temperature of the high-silicon negative electrode battery during the charging and discharging process to obtain the real-time temperature;

[0110] The second detection unit is used to detect the real-time resistance of the SEI film.

[0111] Specifically, the first detection unit can be a temperature sensor, such as a thermocouple or thermistor, which is directly installed on the surface or inside of the battery to monitor the battery temperature in real time. Its specific structure is not limited here, and the resistance of the SEI film can be measured by electrochemical impedance spectroscopy (EIS) technology.

[0112] Specifically, by detecting temperature and SEI film resistance, the system can fully grasp the working status of high-silicon negative electrode batteries, providing a solid foundation for precise control. Continuous real-time detection enables the system to capture subtle changes in battery status in a timely manner, achieve rapid response and adjustment, and effectively prevent potential problems. It is suitable for different working conditions and charging and discharging strategies, enhancing the flexibility and adaptability of the system.

[0113] Specifically, the detection module further includes a third detection unit, which is used to detect the concentration of the additive in the electrolyte to obtain the real-time concentration of the additive.

[0114] Specifically, the third detection unit can obtain the real-time concentration of the additive by setting an electrochemical sensor in the electrolyte and using high performance liquid chromatography or gas chromatography-mass spectrometry analysis, and its specific structure is not limited here.

[0115] Specifically, by detecting the concentration of additives in real time, the system can accurately grasp the state of the electrolyte and the consumption of additives, which helps to replenish them in time to prevent a sharp decline in battery performance or safety hazards caused by the depletion of additives, maintain the optimal performance of the electrolyte, and thus extend the service life of the battery.

[0116] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A charge and discharge control system for a high silicon negative electrode battery electrolyte, characterized in that: include: A high silicon negative electrode battery, comprising a high silicon negative electrode, an electrolyte and an additive, wherein the electrolyte forms a SEI film on the surface of the high silicon negative electrode under the action of the additive during the charge and discharge process; A detection module, which is connected to the high-silicon negative electrode battery and is used to detect the real-time temperature of the high-silicon negative electrode battery during the charging and discharging process, the real-time resistance of the SEI film, and the real-time concentration of the additive; a data processing module connected to the detection module, for determining whether the SEI film state is good or not according to the real-time resistance in a resistance threshold interval formed by a minimum SEI film resistance threshold and a maximum SEI film resistance threshold when the real-time temperature meets a preset temperature threshold range, so as to obtain a determination result; An adjustment control module, connected to the high-silicon negative electrode battery pack and the data processing module, for adjusting the temperature when the real-time temperature does not meet the preset temperature threshold range; When the determination result is that the SEI film state is poor, adjusting the charge and discharge current according to the relationship between the real-time resistance and the minimum SEI film resistance threshold or the maximum SEI film resistance threshold; And, when the judgment result is that the SEI film is in good condition, the real-time consumption rate is calculated according to the real-time concentration, and the additive replenishment amount is determined according to the real-time consumption rate.

2. The charge and discharge control system of the high silicon negative electrode battery electrolyte according to claim 1, characterized in that: The data processing module comprises: A first determination unit, configured to determine whether the temperature is abnormal according to the real-time temperature; The second determination unit is connected to the first determination unit and is used to determine whether the SEI film is in a good state according to the real-time resistance.

3. The charge and discharge control system of the high silicon negative electrode battery electrolyte according to claim 2, characterized in that: The first determination unit includes a first setting subunit, a first comparing subunit and a first determination subunit, wherein: The first setting subunit is used to set the maximum charge and discharge temperature and the minimum charge and discharge temperature; The first comparison subunit is connected to the first setting subunit, and is used to compare the real-time temperature with the highest charge and discharge temperature and the lowest charge and discharge temperature to obtain a comparison result; The first determination subunit is connected to the first comparison subunit and is used to determine whether the temperature is abnormal according to the comparison result.

4. The charge and discharge control system of the high silicon negative electrode battery electrolyte according to claim 3, characterized in that: The first sub-determination unit determines that the temperature is abnormal when the real-time temperature is greater than the maximum charge and discharge temperature or less than the minimum charge and discharge temperature; The first determination subunit determines that the temperature is normal when the real-time temperature is neither less than the lowest charge and discharge temperature nor greater than the highest charge and discharge temperature.

5. The charge and discharge control system of the high silicon negative electrode battery electrolyte according to claim 4, characterized in that: The second determination unit includes a second setting subunit, a second comparison subunit and a second determination subunit, wherein: The second setting subunit is used to set a minimum SEI film resistance threshold and a maximum SEI film resistance threshold; The second comparison subunit is used to compare the real-time resistance with the resistance threshold range to determine whether the charge and discharge current of the high-silicon negative electrode battery needs to be changed; If the SEI film resistance is less than the minimum SEI film resistance threshold, the second determination unit determines that the SEI film state is poor; If the SEI film resistance is greater than the maximum SEI film resistance threshold, the second determination unit determines that the SEI film state is poor; If the SEI film resistance is neither less than the minimum SEI film resistance threshold nor greater than the maximum SEI film resistance threshold, the second determination unit determines that the SEI film is in good condition.

6. The high silicon negative electrode battery electrolyte charge and discharge control system according to claim 5, characterized in that: The adjustment control module adjusts the temperature according to the real-time temperature when the first determination unit determines that the temperature is abnormal. When the real-time temperature is lower than the lowest preset temperature, the temperature is increased and adjusted according to the difference between the real-time temperature and the highest preset temperature; When the real-time temperature is greater than the highest preset temperature, the temperature is adjusted to be lowered according to the difference between the real-time temperature and the lowest preset temperature.

7. The charge and discharge control system of the high silicon negative electrode battery electrolyte according to claim 6, characterized in that: The adjustment control module adjusts the charge and discharge current according to the relationship between the real-time resistance and the minimum SEI film resistance threshold and the maximum SEI film resistance threshold when the second determination unit determines that the SEI film state is poor, When the SEI membrane resistance is less than the minimum SEI membrane resistance threshold, the charge and discharge current is adjusted by a fixed increment until the real-time resistance is within the resistance threshold interval; When the SEI film resistance is greater than the minimum SEI film resistance threshold, the charge and discharge current is adjusted to a fixed decrement until the real-time resistance is within the resistance threshold interval.

8. The charge and discharge control system of the high silicon negative electrode battery electrolyte according to claim 7, characterized in that: When the second determination unit determines that the SEI film is in good condition, the adjustment control module predicts the additive concentration consumption according to the real-time consumption rate, predicts the additive consumption according to the real-time consumption rate, and determines the additive replenishment amount based on the additive consumption.

9. The high silicon negative electrode battery electrolyte charge and discharge control system according to claim 8, characterized in that: The detection module comprises: A first detection unit, which is used to detect the temperature of the high-silicon negative electrode battery during the charging and discharging process to obtain the real-time temperature; The second detection unit is used to detect the real-time resistance of the SEI film.

10. The high silicon negative electrode battery electrolyte charge and discharge control system according to claim 9, characterized in that: The detection module also includes a third detection unit, which is used to detect the concentration of the additive in the electrolyte to obtain the real-time concentration of the additive.

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