Reversible charge-discharge cycle co-electrolysis control method

Abstract

The invention provides a reversible charge-discharge cycle co-electrolysis control method, which is applied to an automobile battery charge-discharge monitoring device and comprises the following steps: acquiring current state information of a lithium battery pack; judging whether to start a temperature monitoring module according to the state information; if yes, monitoring the temperature of the lithium battery pack to obtain first monitoring data; judging whether to start a pressure monitoring module according to the first monitoring data; if the pressure monitoring module is started, monitoring the pressure of the lithium battery pack to obtain second monitoring data; judging whether to start a volume monitoring module according to the second monitoring data; if the volume monitoring module is started, monitoring the volume of the lithium battery pack to obtain third monitoring data; and increasing or decreasing the current or output power of the lithium battery pack during charging or discharging according to the first, second and third monitoring data. The technical problem that in the prior art, monitoring on the lithium battery is concentrated on the temperature aspect, and the change condition of the battery volume cannot be directly fed back to a user is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery charging and discharging, and in particular to a control method for reversible charging and discharging cycle co-electrolysis. Background Art

[0002] With the development of economy and society, the demand for energy is also growing; in order to respond to sustainable development, it is imperative to develop new energy and renewable resources.

[0003] Taking electric vehicles as an example, most electric vehicles use lithium batteries as their energy devices. Lithium batteries are a kind of chemical energy storage device. They have the characteristics of high specific energy, large output power, excellent rate performance, long cycle life and good safety, and have been widely used and vigorously promoted.

[0004] However, a large amount of heat is generated during the charging and discharging process of lithium batteries, causing the overall temperature to change, thereby affecting the capacity and performance of the battery. In some extreme cases, thermal runaway may occur, resulting in major safety accidents. Therefore, it is necessary to monitor the charging and discharging process to ensure that the battery is within a reasonable temperature range.

[0005] The existing technology for monitoring lithium batteries mainly focuses on temperature and battery performance, and adjusts the current or voltage of the lithium battery during charging or discharging by monitoring temperature changes. This causes at least one of the following problems: there is a lack of monitoring of the volume change of the lithium battery, and the user cannot determine whether the lithium battery is expanding or bulging by temperature, which may cause safety accidents. Summary of the invention

[0006] The technical problem solved by the present invention is that the existing technology for monitoring lithium batteries mainly focuses on temperature and battery performance, and adjusts the current or voltage of the lithium battery during charging or discharging by monitoring temperature changes. There is a lack of monitoring of the volume changes of the lithium battery. Users cannot judge whether the lithium battery is expanding or bulging by temperature, which may cause safety accidents.

[0007] To solve the above problems, the present invention provides a control method for reversible charge-discharge cycle co-electrolysis, the control method is applied to an automobile battery charge-discharge monitoring device, the automobile battery charge-discharge monitoring device comprises: a temperature monitoring module, a pressure monitoring module and a volume monitoring module; the control method comprises: obtaining current status information of a lithium battery pack; judging whether to start the temperature monitoring module according to the status information; if so, controlling the temperature monitoring module to monitor the temperature of the lithium battery pack and obtaining first monitoring data; judging whether to start the pressure monitoring module according to the first monitoring data; if the pressure monitoring module is started, controlling the pressure monitoring module to monitor the pressure of the lithium battery pack and obtaining second monitoring data; judging whether to start the volume monitoring module according to the second monitoring data; if the volume monitoring module is started, controlling the volume monitoring module to monitor the volume of the lithium battery pack and obtaining third monitoring data; increasing or decreasing the charging current of the lithium battery pack in a charging state or the output power in a discharging state according to the first monitoring data, the second monitoring data and the third monitoring data, and providing feedback to the user.

[0008] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: compared with the related art in which the monitoring of lithium batteries is mainly focused on temperature and battery performance, the present invention performs comprehensive monitoring of the lithium battery pack by sequentially starting the temperature monitoring module, the pressure monitoring module and the volume monitoring module, and can obtain the status information of the lithium battery pack in multiple dimensions, evaluate the safety of the battery more comprehensively, and adjust the charging current of the lithium battery pack or the output power in the discharge state according to the monitoring data, and provide feedback to the user at the same time; it realizes dynamic monitoring and control of the charging and discharging process of the lithium battery pack, and improves the safety and efficiency of battery use.

[0009] In one example of the present invention, the automobile battery charge and discharge monitoring device also includes: a protection module; defining the temperature of the lithium battery pack under normal working conditions as a first temperature; controlling the temperature monitoring module to monitor the temperature of the lithium battery pack and obtaining first monitoring data, including: obtaining the temperature change rate of the first temperature in the first time period; judging whether the first temperature is in a preset temperature fluctuation range according to the temperature change rate; if not, sending a first signal to the user, and controlling the protection module to perform pre-cooling treatment on the lithium battery pack; monitoring the first temperature multiple times in the first time period in the future; judging whether the fluctuation difference formed between the multiple first temperatures obtained in the multiple monitorings and the preset temperature fluctuation range falls within the temperature fluctuation difference range; if so, sending a first signal to the user, and controlling the temperature monitoring module to periodically monitor the lithium battery pack; if not, sending a second signal to the user, and controlling the pressure monitoring module to perform pressure monitoring on the lithium battery pack; wherein the first signal includes a safety signal, and the second signal includes a prompt signal, a warning signal, and an alarm signal.

[0010] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: by monitoring the temperature change rate and fluctuation difference, a signal is sent to the user when the temperature is abnormal and the protection module is activated for pre-cooling treatment, and multiple monitoring is performed in the first time period in the future to further determine whether to start the pressure monitoring module. It provides a specific method and process for temperature monitoring of lithium battery packs, improving the accuracy and reliability of temperature monitoring; at the same time, through accurate temperature monitoring and timely pre-cooling treatment, it can effectively prevent safety risks caused by battery overheating, and sending signals to users can allow users to understand the battery status in time and take corresponding measures.

[0011] In one example of the present invention, it is determined whether the fluctuation difference formed between multiple first temperatures obtained in multiple monitorings and a preset temperature fluctuation range falls within the temperature fluctuation difference range, including: obtaining temperature data of the lithium battery pack in a first time period in the future, recorded as a second temperature; comparing the second temperature with a temperature threshold to obtain a first comparison result; judging whether the second temperature is between a maximum temperature threshold and a minimum temperature threshold based on the first comparison result; if not, determining that the lithium battery pack is in a first dangerous state, and executing a first emergency plan.

[0012] In one example of the present invention, the second temperature is compared with the temperature threshold to obtain a first comparison result, including: dividing the lithium battery group into regions according to the first comparison result; dividing at least one lithium battery above the maximum temperature threshold into a first battery group, and the remaining lithium batteries into a second battery group; wherein the first battery group is a high temperature area.

[0013] Compared with the existing technology, the technical effect achieved by adopting this technical solution is that the lithium battery pack can be divided into regions for more targeted monitoring and processing. For example, when the temperature of some batteries is detected to be too high, the high-temperature area can be quickly located, and the batteries in the area can be cooled or other measures can be taken. At the same time, the surrounding batteries can be monitored to prevent the temperature from spreading; this can improve the processing efficiency and reduce the impact on the entire battery pack.

[0014] In one example of the present invention, it is determined that the lithium battery pack is in a first dangerous state, and a first emergency plan is executed, including: obtaining the current remaining power and power consumption rate of the lithium battery pack; cooling the lithium battery pack; judging whether the lithium battery pack has the possibility of completing the remaining journey after the cooling process; if not, sending a second signal to the user, controlling the vehicle's driving speed to be reduced to the minimum speed specified for the current road section, and sending a help signal to the relevant department; if so, controlling the protection module to continuously cool the lithium battery pack to the first temperature, obtaining the road conditions of the remaining journey in the historical period, and controlling the vehicle to start the cruise control mode according to the remaining power.

[0015] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: when the lithium battery pack is in a dangerous state, the driving state of the car is reasonably controlled according to the remaining power and the power consumption rate, which can provide users with more choices and guarantees.

[0016] In one example of the present invention, the pressure of a lithium battery pack under normal conditions is defined as a first pressure; the pressure monitoring module includes multiple anchor points set up on the outer surface of the lithium battery pack, which are used to measure the surface flatness of the lithium battery pack; the pressure monitoring module is controlled to perform pressure monitoring on the lithium battery pack, including: obtaining first flatness data of each anchor point; when the lithium battery pack is determined to be in a first dangerous state, controlling multiple anchor points to monitor the lithium battery pack within a first time period in the future to obtain second flatness data; generating outer surface change data of the lithium battery pack based on the first flatness data and the second flatness data; judging whether it is necessary to perform a second processing strategy on the lithium battery pack based on the outer surface change data; if so, controlling the protection module to perform pressure relief processing on the lithium battery pack.

[0017] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by monitoring the flatness of the outer surface of the lithium battery pack and timely pressure relief treatment, the lithium battery pack can be effectively prevented from being deformed, leaked or even exploded due to abnormal pressure. For example, if abnormal pressure is detected, the system will generate outer surface change data and determine whether to perform pressure relief treatment based on this data.

[0018] In one example of the present invention, outer surface change data of a lithium battery pack is generated based on first flatness data and second flatness data, including: judging whether the anchor point is in the first battery pack based on the second flatness data of each anchor point; if so, controlling the protection module to execute the second emergency plan, marking the lithium battery pack corresponding to the anchor point as a high temperature and high pressure area, marking the remaining lithium battery packs arranged around it as temperature spread areas, and controlling the volume monitoring module to monitor the lithium battery pack; wherein the second emergency plan includes performing pressure relief treatment on the high temperature and high pressure area, and starting the liquid cooling function to cool the lithium battery.

[0019] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: executing the second emergency plan can quickly respond to problems in high temperature and high pressure areas and prevent the spread of faults; for example, when a battery is detected to have high temperature and high pressure, the system can immediately mark the area as a dangerous area and monitor and protect the surrounding batteries; at the same time, starting the liquid cooling function for cooling operations can quickly lower the battery temperature and reduce safety risks; in addition, sending alarms to users allows users to understand the situation in a timely manner and take corresponding measures.

[0020] In one example of the present invention, the volume monitoring module is controlled to monitor the lithium battery pack, including: establishing a three-dimensional volume model for the lithium battery pack; gridding the lithium battery pack to obtain the coordinates of any cube on the lithium battery pack; controlling the volume monitoring module to monitor at least one cube located in the high temperature and high pressure area to obtain third monitoring data; judging whether the battery safety of the lithium battery corresponding to the cube meets the charging and discharging standards in the first time period in the future based on the third monitoring data; if not, cutting off the power supply of the lithium battery corresponding to the cube, and reducing the output power of the remaining lithium batteries arranged around the lithium battery.

[0021] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by establishing a three-dimensional volume model and gridding the lithium battery pack, the volume changes of the battery can be monitored more accurately. Through volume monitoring, problems such as battery expansion can be discovered in a timely manner. When it is detected that the safety of the lithium battery corresponding to a cube does not meet the charging and discharging standards, its power supply is cut off and the output power of the surrounding lithium batteries is reduced, which can effectively prevent the spread of faults and ensure the overall safety of the equipment.

[0022] In one example of the present invention, a volume monitoring module is controlled to monitor at least one cube located in a high temperature and high pressure area, including: controlling the inner cell of a lithium battery as a source boundary; controlling the outer shell of a lithium battery as a target boundary; controlling the expansion of the inner cell to directly act on the outer shell; controlling the outer shell as a boundary constraint for the volume expansion of the lithium battery; obtaining the relationship between the volume of the cube and the temperature in a first time period in the future; and dynamically adjusting the output power of the lithium battery according to the change relationship.

[0023] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by controlling the inner cell and outer shell of the lithium battery as the source boundary and target boundary, the relationship between the change of the cube volume and the temperature is obtained, the volume change trend of the battery can be predicted more accurately, and the output power can be dynamically adjusted according to this change relationship, which can avoid performance degradation and safety risks caused by battery volume expansion.

[0024] After adopting the technical solution of the present invention, the following technical effects can be achieved: (1) The combination of the temperature monitoring module, the pressure monitoring module and the volume monitoring module can provide users with accurate early warnings. The temperature monitoring module monitors the temperature of the battery in real time, and the control center makes corresponding processing strategies based on the temperature, so that users have enough time to take measures, such as stopping use and maintaining the battery, to reduce safety risks; (2) It can help to more accurately diagnose the type and cause of battery failure. For example, if the temperature rises but the pressure and volume do not change much, it may be a heat dissipation problem; if the pressure and volume change significantly but the temperature is normal, it may be internal structural damage; (3) The control center is connected to the user through the network. The user can obtain the real-time status information of the battery anytime and anywhere through the mobile terminal, without being restricted by time and space. Once abnormal data is monitored, the alarm generation unit can quickly issue an alarm to notify the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings to be used in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. Figure 1 A schematic flow chart of a control method for reversible charge-discharge cycle co-electrolysis provided in an embodiment of the present invention; Figure 2 A module connection diagram of a control system for reversible charge-discharge cycle co-electrolysis provided in an embodiment of the present invention.

[0026] Description of reference numerals: 100. Control system; 10. Temperature monitoring module; 20. Pressure monitoring module; 30. Volume monitoring module; 40. Control center. DETAILED DESCRIPTION

[0027] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0028] In the description of this application, it should be noted that, 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, or it can be connected, or it can be connected in one piece; it can be a mechanical connection or an electrical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] See also Figure 1 , Figure 1A flow chart of a control method for reversible charge-discharge cycle co-electrolysis provided by an embodiment of the present invention; specifically, a control method for reversible charge-discharge cycle co-electrolysis, the control method is applied to an automobile battery charge-discharge monitoring device, the automobile battery charge-discharge monitoring device includes: a temperature monitoring module, a pressure monitoring module and a volume monitoring module; the control method includes: S1: Get the current status information of the lithium battery pack; S2: Determine whether to start the temperature monitoring module according to the status information; S21: If yes, control the temperature monitoring module to monitor the temperature of the lithium battery pack to obtain first monitoring data; S22: If not, determine that the lithium battery pack meets the safe working conditions, and maintain the current output power of the lithium battery pack; S3: Determine whether to start the pressure monitoring module according to the first monitoring data; S31: If the pressure monitoring module is started, the pressure monitoring module is controlled to monitor the pressure of the lithium battery pack and obtain second monitoring data; S32: If the pressure monitoring module is not started, it is determined that the current pressure of the lithium battery pack meets the safe working conditions; S4: Determine whether to start the volume monitoring module according to the second monitoring data; S41: if the volume monitoring module is started, the volume monitoring module is controlled to monitor the volume of the lithium battery pack and obtain third monitoring data; S42: If the volume monitoring module is not started, determining whether the current volume change of the lithium battery pack meets the safe working conditions; S5: increasing or decreasing the charging current of the lithium battery pack in the charging state or the output power in the discharging state according to the first monitoring data, the second monitoring data and the third monitoring data, and providing feedback to the user.

[0031] Preferably, the temperature of the lithium battery pack in normal working condition is defined as the first temperature; the pressure to which the lithium battery pack is subjected in normal working condition is defined as the first pressure; and the volume of the lithium battery pack in normal working condition is defined as the first volume.

[0032] Preferably, the temperature monitoring module 10 collects temperature data once a second and sends it to the control center 40; the pressure monitoring module 20 collects internal pressure data and external pressure data every ten seconds and sends them to the control center 40; the volume monitoring module 30 performs a three-dimensional scan of the lithium battery pack every thirty seconds and sends the scan data to the control center 40.

[0033] Specifically, multiple monitoring devices are set on the car to monitor the charging or discharging process of the car in real time; by monitoring its temperature, internal pressure, external pressure and volume changes, the current state of the lithium battery pack is gradually analyzed in depth, and combined with the state of the lithium battery pack, feedback is given to the user to help the user understand the state of the lithium battery pack during charging or discharging, so that the user can take emergency actions in time according to the total monitoring data to reduce the phenomenon of expansion or bulging of the car during charging or discharging.

[0034] Preferably, the lithium battery pack is arranged at a battery installation position of the automobile, and the lithium battery pack is composed of a plurality of lithium batteries.

[0035] Furthermore, the automobile battery charge and discharge monitoring device further includes: a protection module; and a temperature monitoring module that controls the temperature of the lithium battery pack to monitor the temperature of the lithium battery pack and obtains first monitoring data, including: Obtaining a temperature change rate of a first temperature in a first time period; determining whether the first temperature is within a preset temperature fluctuation range according to the temperature change rate; If yes, a first signal is sent to the user, and the temperature monitoring module is controlled to periodically monitor the lithium battery pack; If not, sending a second signal to the user and executing the first processing strategy; Monitoring the first temperature multiple times in a first future time period; Determine whether the fluctuation difference between the multiple first temperatures obtained in multiple monitorings and the preset temperature fluctuation range falls within the temperature fluctuation difference range; If not, a second signal is sent to the user, and the pressure monitoring module is controlled to perform pressure monitoring on the lithium battery pack; Among them, the first signal includes a safety signal, and the second signal includes a prompt signal, a warning signal and an alarm signal.

[0036] Preferably, the first processing strategy includes sending a prompt signal to the user, controlling the pressure monitoring module 20 to monitor the internal pressure and external pressure of the lithium battery, and controlling the protection module to perform a temperature reduction process on the lithium battery pack.

[0037] Among them, the temperature change rate can be used to more accurately predict the first temperature at a certain moment in the future, judge the development trend of the battery temperature in advance, and adjust the battery management strategy in real time according to the temperature changes to ensure the safe operation of the vehicle and prevent the car's battery from having thermal runaway and other safety risks at high temperatures and performance degradation at low temperatures.

[0038] Furthermore, since the performance and safety of lithium batteries are very sensitive to temperature, therefore, firstly, by obtaining the temperature change rate of the lithium battery pack in the first time period, the development trend of the first temperature at a certain moment in the future is predicted in advance, and by judging whether the first temperature is in a preset temperature fluctuation range through the temperature change rate, the temperature of the lithium battery pack is dynamically adjusted to keep it within a suitable temperature range. By setting the preset temperature fluctuation range and the temperature fluctuation difference range, the temperature change can be quantitatively evaluated to more accurately judge the working status of the battery.

[0039] Further, determining whether the fluctuation difference between the multiple first temperatures obtained in the multiple monitorings and the preset temperature fluctuation range falls within the temperature fluctuation difference range includes: Acquire temperature data of the lithium battery pack in a first time period in the future, recorded as a second temperature; Comparing the second temperature with the temperature threshold to obtain a first comparison result; Determine whether the second temperature is between a maximum temperature threshold and a minimum temperature threshold according to the first comparison result; If not, it is determined that the lithium battery pack is in a first dangerous state, and the first emergency plan is executed.

[0040] Further, the second temperature is compared with the temperature threshold to obtain a first comparison result, including: Dividing the lithium battery pack into regions according to the first comparison result; Divide at least one lithium battery having a temperature higher than a maximum threshold into a first battery group, and the remaining lithium batteries into a second battery group; Among them, the first battery group is a high temperature area.

[0041] Specifically, when the second temperature of the lithium battery pack in the first time period in the future is greater than or less than the temperature threshold, the lithium battery pack is determined to be in a dangerous state; at the same time, the lithium batteries in the lithium battery pack will be divided into regions according to the second temperature, that is, the lithium batteries above the maximum temperature threshold are divided into the first battery group, corresponding to the high temperature area, and the remaining lithium batteries are the second battery group.

[0042] Preferably, the first battery group is in a high temperature area, and the second battery group is in a normal temperature area.

[0043] It should be noted that by dividing the lithium battery pack into a first battery group and a second battery group, and through the first comparison result, the relative degree of change between the lithium batteries in different positions can be found out, so as to more accurately evaluate the working status of the battery pack; even if the individual lithium batteries themselves may not reach the preset dangerous temperature threshold, the abnormal difference between the first comparison results of the parameters can also indicate the uneven heating situation inside the lithium battery pack, which is helpful to discover potential faults or safety hazards in advance.

[0044] Further, it is determined that the lithium battery pack is in a first dangerous state, and a first emergency plan is executed, including: Get the current remaining power and power consumption rate of the lithium battery pack; Cool down the lithium battery pack; Determine whether the lithium battery pack has the possibility of completing the remaining journey after cooling down; If not, a second signal is sent to the user to control the vehicle's speed to be reduced to the minimum speed specified for the current road section, and a signal for assistance is sent to the relevant department; If so, the protection module is controlled to continuously cool the lithium battery pack to the first temperature, obtain the road conditions of the remaining journey in the historical period, and control the vehicle to start the cruise control mode according to the remaining power.

[0045] For example, during the driving of the car, the first temperature of the lithium battery pack will change with the driving conditions; the preset temperature fluctuation range is defined as 20℃-40℃, and the temperature fluctuation difference range is ±5℃; under normal driving conditions, the battery temperature of the car may fluctuate around 30℃; but if the car is driving at high speed or climbing for a long time, the load of the battery increases and the temperature tends to rise; therefore, obtaining the temperature change rate of the first temperature in the first time period can predict in advance the change of the battery temperature of the car on the future road section; for example, the reference temperature is set to 35℃, when the first temperature is not in the preset fluctuation range, and the fluctuation difference between the first temperature obtained by multiple monitoring in the first time period in the future and the preset temperature fluctuation range does not fall into the temperature fluctuation difference range, for example, the temperature monitoring module 10 continuously monitors the temperature of 38℃, 40℃ and 31℃, and the subsequent temperature fluctuation differences are 3℃, 5℃ and -4℃ respectively, and these fluctuation differences fall within the temperature fluctuation difference range of ±5℃, indicating that although the current battery temperature has fluctuated If the temperature of the lithium battery pack continues to rise to 45°C, it exceeds the preset temperature fluctuation range, and the fluctuation difference also exceeds the temperature difference fluctuation range. At this time, the first emergency plan should be implemented. According to the current remaining power and power consumption rate of the lithium battery pack, it is predicted whether the car can complete the remaining journey. If it can be completed, the temperature of the lithium battery pack in the high temperature area is reduced to the normal operating temperature. The control center 40 exchanges information with the user terminal to obtain the road condition information between the current position and the target position, calculates the optimal driving speed in accordance with the regulations according to the remaining power, and controls the vehicle to start the cruise control mode to avoid frequent braking or acceleration, so as to save power and maintain the battery output power. If not, the vehicle speed is reduced to the minimum speed specified in the current section, and a help signal is sent.

[0046] Furthermore, the pressure monitoring module 20 includes a plurality of anchor points mounted on the outer surface of the lithium battery pack, which are used to measure the surface flatness of the lithium battery pack; controlling the pressure monitoring module to perform pressure monitoring on the lithium battery pack includes: Obtain the first flatness data of each anchor point; When it is determined that the lithium battery pack is in a first dangerous state, controlling the plurality of anchor points to monitor the lithium battery pack in a first future time period to obtain second flatness data; Generate outer surface variation data of the lithium battery pack according to the first flatness data and the second flatness data; Determining whether a second processing strategy is required for the lithium battery pack according to the external surface change data; If yes, the protection module is controlled to release the pressure on the lithium battery pack.

[0047] Preferably, the first flatness data is measured when the lithium battery pack is in a normal working state.

[0048] Preferably, the second processing strategy includes sending a warning signal to the user and controlling the volume monitoring module 30 to monitor the lithium battery pack.

[0049] Further, generating the outer surface variation data of the lithium battery pack according to the first flatness data and the second flatness data specifically includes: determining whether the anchor point is in the first battery group according to the second flatness data of each anchor point; If so, the control protection module executes the second emergency plan, marks the lithium battery corresponding to the anchor point as a high temperature and high pressure area, and the remaining lithium batteries arranged around it as a temperature spread area, and controls the volume monitoring module to monitor the lithium battery pack.

[0050] Preferably, the second emergency plan includes performing pressure relief treatment on the high temperature and high pressure area, and activating the liquid cooling function to cool the lithium battery.

[0051] Specifically, multiple anchor points are set on the outer surface of the lithium battery pack and multiple measuring points are selected, which are marked as: M1, M2, M3...Mn; the surface flatness data of each measuring point of the lithium battery pack under normal working conditions is measured and marked as: D1, D2, D3...Dn; the flatness data of the multiple measuring points monitored after the first time period in the future are Q1, Q2, Q3...Qn respectively; the outer surface change data of the lithium battery pack is generated according to the first flatness data and the second flatness data, that is, the change in flatness of each measuring point is: ΔMt=Qt-Dt, where t={1, 2, 3...n}; the change in flatness of the corresponding multiple measuring points of the lithium battery pack in the first time period in the future is compared with Formula 1, Formula 1: ; It can be concluded whether the lithium battery pack meets the safe working conditions in the first time period in the future; If not, the position of each anchor point will be fitted with the area where the first battery group is located, and then the anchor points that fall into the first battery group, i.e. the high temperature area, will be screened out, and the anchor points and the area where they are located will be divided into a high temperature and high pressure area, and the remaining lithium batteries arranged around it will be the temperature spread area.

[0052] Among them, ΔMtmin is the lower limit of the flatness change, ΔMtmax is the upper limit of the flatness change, C is the change coefficient, and t is the first time period in the future.

[0053] Furthermore, the above content is the internal pressure detection of the surface flatness change caused by the internal chemical reaction of the lithium battery. In addition to the above monitoring of the internal pressure of the lithium battery pack, the pressure monitoring of the lithium battery pack also monitors the external pressure it is subjected to; the influence of pressure on lithium batteries is multifaceted. Appropriate pressure can make the positive and negative pole pieces and the diaphragm inside the battery close contact, improve the battery charge and discharge reaction interface, reduce the battery internal resistance and polarization, thereby improving the battery cycle stability and high-rate charge and discharge performance. Too low pressure will reduce the electrode reaction area, deteriorate the reaction interface, increase the battery internal resistance and polarization, reduce the battery capacity, and cause the electrode material to fall off from the current collector after a long cycle, seriously affecting the battery life. Too high pressure will destroy the pore structure of the electrode material and the diaphragm, deteriorate the reaction interface, and increase the battery internal resistance, thereby causing the battery capacity to decay rapidly. In severe cases, it will also cause the battery to short-circuit internally, resulting in the risk of thermal runaway, etc.; when a pressure of 0.05MPa-0.5MPa is applied to the outside of the lithium battery pack, it helps to improve the battery cycle stability and battery life, so as to increase the battery capacity.

[0054] The present invention will not elaborate on the monitoring of the external pressure of the lithium battery pack, and its basic idea is similar to that of monitoring the internal pressure thereof.

[0055] Furthermore, the volume monitoring module is controlled to monitor the lithium battery pack, including: Establish a three-dimensional volume model for the lithium battery pack; Grid the lithium battery pack and obtain the coordinates of any cube on the lithium battery pack; The control volume monitoring module monitors at least one cube located in the high temperature and high pressure area to obtain third monitoring data; Determine whether the battery safety of the lithium battery corresponding to the cube meets the charging and discharging standards in the first time period in the future according to the third monitoring data; If not, an alarm signal is sent to the user, and the power supply of the corresponding lithium battery of the cube is cut off, and the output power of the remaining lithium batteries arranged around the lithium battery is reduced.

[0056] For example, the shape of the lithium battery pack is input into the control center, and the control center generates its corresponding three-dimensional volume model; thus, the lithium battery pack is gridded, that is, each lithium battery is regarded as a cube, and the coordinate position corresponding to its location in the space within the lithium battery pack is obtained; assuming that it is monitored that there are several cubes located in the high temperature and high pressure area, the positions of these cubes can be locked by the control center, and then corresponding treatment measures can be taken for the lithium batteries.

[0057] Furthermore, the control volume monitoring module monitors at least one cube located in the high temperature and high pressure area, including: Control the inner cell of the lithium battery as the source boundary; Control the outer shell of the lithium battery as the target boundary; Control the expansion of the inner battery cell to directly act on the outer shell; Controlling the outer shell as a boundary constraint for the volume expansion of lithium batteries; Obtain the relationship between the volume of the cube and the temperature in the first future time period; Dynamically adjust the output power of the lithium battery according to the changing relationship.

[0058] Combined with the actual situation, the inner battery cell is regarded as the source of the volume change and other effects. When the inner battery cell undergoes a chemical reaction and causes expansion, this is the starting point of the volume change; the outer shell of the lithium battery is controlled as the target boundary, and the outer shell limits the expansion range of the inner battery cell; when the inner battery cell expands, it directly acts on the outer shell. For example, if the volume of the inner battery cell increases due to temperature increase or other reasons, it will exert pressure on the outer shell, which may cause the volume of the lithium battery to change; the outer shell is used as a boundary constraint for the volume expansion of the lithium battery to ensure that the expansion is within a certain range; the relationship between the volume change of the cube with temperature in the first time period in the future is obtained; through monitoring and data analysis, the volume change trend of the lithium battery with the increase of temperature can be obtained; the output power of the lithium battery is dynamically adjusted according to this change relationship. If it is found that the volume changes too quickly with temperature, it means that the battery may have a safety risk, and its output power is reduced to reduce heat generation and further volume changes. Furthermore, the vehicle charging and discharging monitoring device is also provided with a road condition prediction module connected to the user's mobile terminal; the road condition type of the vehicle in the first time period in the future is predicted according to the road condition prediction module, specifically including: If it is an uphill or speed-changing section, the control center controls the normal temperature area of ​​the lithium battery pack to increase the output power to reduce the load in the high-temperature area, and jointly provide power for the car with the high-temperature area, providing stable power to the high-temperature area, so that the high-temperature area can be quickly replenished.

[0059] If it is a downhill section, the control center controls the generator to perform power braking to charge the lithium battery pack.

[0060] If the road is bumpy or steep, the suspension parameters of the car will be adjusted to prevent the lithium battery pack from being damaged by external impact, and the output power of the lithium battery pack will be reduced to reduce the additional pressure on the lithium battery pack caused by the vibration when the vehicle is driving on bumpy or steep roads. An early warning signal will be sent to the user's mobile terminal to remind the user to drive carefully.

[0061] Furthermore, the automobile charge and discharge monitoring device further includes: a weather monitoring module, which is arranged in the user's mobile terminal and is in communication connection with the control center 40, and the weather monitoring module is used to monitor the weather when the user is driving the car, and determine whether the working environment of the lithium battery pack is met; Predict whether the weather change type in the first time period in the future meets the temperature drop condition according to the weather monitoring module; If yes, then determine whether the weather change type includes rainy weather or snowy weather; If the weather change type is determined to be rainy weather or snowy weather, the control center controls the protection module to regulate the temperature of the lithium battery pack and activates the temperature compensation function to keep the temperature of the lithium battery pack at the first temperature.

[0062] See also Figure 2 The present invention also provides a control system 100 for reversible charge-discharge cycle co-electrolysis, which can apply the control method in any of the above examples. The control system 100 includes: a temperature monitoring module 10, a pressure monitoring module 20, a volume monitoring module 30, a control center 40, a data storage function module and a data analysis and processing unit; wherein the temperature monitoring module 10 is used to monitor the temperature of the lithium battery pack during charging or discharging to obtain first monitoring data; to monitor the external pressure and internal pressure of the lithium battery pack during charging or discharging to obtain second monitoring data; to monitor the volume change of the lithium battery pack during charging or discharging to obtain The third monitoring data is obtained; the control center 40 increases or decreases the charging current of the lithium battery pack in the charging state or the output power in the discharging state according to the total monitoring data, and feeds back to the user; the data storage function module saves the data of the control center 40 and each monitoring module for subsequent analysis and tracing; the data analysis and processing unit can receive and process the data from each monitoring module, and send an alarm to the user through the alarm generation unit; wherein the total monitoring data includes at least one of the first monitoring data, the second monitoring data and the third monitoring data, and the control center 40 is connected to the user's mobile terminal through a network, and pushes the monitoring results and alarm information to the user in real time.

[0063] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A control method for reversible charge-discharge cycle co-electrolysis, characterized in that: The control method is applied to a vehicle battery charge and discharge monitoring device, which includes: a temperature monitoring module, a pressure monitoring module and a volume monitoring module; the control method includes: Get the current status information of the lithium battery pack; Determine whether to start the temperature monitoring module according to the status information; If yes, control the temperature monitoring module to monitor the temperature of the lithium battery pack to obtain first monitoring data; Determining whether to start a pressure monitoring module according to the first monitoring data; If the pressure monitoring module is started, the pressure monitoring module is controlled to monitor the pressure of the lithium battery pack and obtain second monitoring data; Determining whether to start the volume monitoring module according to the second monitoring data; If the volume monitoring module is started, the volume monitoring module is controlled to monitor the volume of the lithium battery pack and obtain third monitoring data; The charging current of the lithium battery pack in a charging state or the output power in a discharging state is increased or decreased according to the first monitoring data, the second monitoring data and the third monitoring data, and feedback is given to the user.

2. The control method according to claim 1, characterized in that: The automobile battery charge and discharge monitoring device further includes: a protection module; defining the temperature of the lithium battery pack under normal working conditions as a first temperature; and controlling the temperature monitoring module to monitor the temperature of the lithium battery pack to obtain first monitoring data, including: Obtaining a temperature change rate of the first temperature in a first time period; determining whether the first temperature is within a preset temperature fluctuation range according to the temperature change rate; If yes, a first signal is sent to the user, and the temperature monitoring module is controlled to periodically monitor the lithium battery pack; If not, sending a second signal to the user, and controlling the protection module to perform a pre-cooling process on the lithium battery pack; Monitoring the first temperature multiple times in a first time period in the future; Determine whether the fluctuation difference between the first temperatures obtained in the multiple monitorings and the preset temperature fluctuation range falls within the temperature fluctuation difference range; If not, sending a second signal to the user, and controlling the pressure monitoring module to perform pressure monitoring on the lithium battery pack; Among them, the first signal includes a safety signal, and the second signal includes a prompt signal, a warning signal and an alarm signal.

3. The control method according to claim 2, characterized in that: The determining whether the fluctuation difference between the first temperatures obtained in the multiple monitorings and the preset temperature fluctuation range falls within the temperature fluctuation difference range includes: Acquire temperature data of the lithium battery pack in the first future time period, recorded as a second temperature; Comparing the second temperature with a temperature threshold to obtain a first comparison result; Determine whether the second temperature is between a maximum temperature threshold and a minimum temperature threshold according to the first comparison result; If not, it is determined that the lithium battery pack is in a first dangerous state, and a first emergency plan is executed.

4. The control method according to claim 3, characterized in that: The comparing the second temperature with the temperature threshold to obtain a first comparison result includes: Dividing the lithium battery pack into regions according to the first comparison result; Divide at least one of the lithium batteries having a temperature higher than the maximum temperature threshold into a first battery group, and the remaining lithium batteries into a second battery group; Wherein, the first battery group is a high temperature area.

5. The control method according to claim 4, characterized in that: The determining that the lithium battery pack is in a first dangerous state and executing a first emergency plan includes: Obtaining the current remaining power and power consumption rate of the lithium battery pack; Performing a cooling process on the lithium battery pack; Determining whether the lithium battery pack has the possibility of completing the remaining journey after the cooling process; If not, the second signal is sent to the user, the driving speed of the vehicle is controlled to be reduced to the minimum speed specified by the current road section, and a help signal is sent to the relevant department; If so, the protection module is controlled to continuously cool the lithium battery pack to the first temperature, the road conditions of the remaining journey in the historical period are obtained, and according to the remaining power, the car is controlled to start the cruise control mode.

6. The control method according to claim 5, characterized in that: The pressure of the lithium battery pack under normal conditions is defined as a first pressure; the pressure monitoring module includes a plurality of anchor points mounted on the outer surface of the lithium battery pack, for measuring the surface flatness of the lithium battery pack; The controlling the pressure monitoring module to perform pressure monitoring on the lithium battery pack includes: Acquire first flatness data of each of the anchor points; When it is determined that the lithium battery pack is in the first dangerous state, controlling the plurality of anchor points to monitor the lithium battery pack within the first future time period to obtain second flatness data; Generate outer surface variation data of the lithium battery pack according to the first flatness data and the second flatness data; Determining whether a second processing strategy needs to be performed on the lithium battery pack according to the outer surface change data; If yes, the protection module is controlled to perform pressure relief processing on the lithium battery pack.

7. The control method according to claim 6, characterized in that: The step of generating the outer surface variation data of the lithium battery pack according to the first flatness data and the second flatness data comprises: determining, according to the second flatness data of each anchor point, whether the anchor point is located in the first battery pack; If yes, the protection module is controlled to execute the second emergency plan, and the lithium battery pack corresponding to the anchor point is marked as a high temperature and high pressure area, and the rest of the lithium battery packs arranged around it are temperature spread areas, and the volume monitoring module is controlled to monitor the lithium battery pack; Among them, the second emergency plan includes performing the pressure relief treatment on the high temperature and high pressure area, and starting the liquid cooling function to cool the lithium battery.

8. The control method according to claim 7, characterized in that: The controlling the volume monitoring module to monitor the lithium battery pack includes: Establishing a three-dimensional volume model for the lithium battery pack; Gridding the lithium battery pack to obtain coordinates of any cube on the lithium battery pack; Controlling the volume monitoring module to monitor at least one cube located in the high temperature and high pressure area to obtain the third monitoring data; Determine, according to the third monitoring data, whether the battery safety of the lithium battery corresponding to the cube meets the charging and discharging standards in the first future time period; If not, the power supply of the lithium battery corresponding to the cube is cut off, and the output power of the remaining lithium batteries arranged around the lithium battery is reduced.

9. The control method according to claim 8, characterized in that: The controlling the volume monitoring module to monitor at least one cube located in the high temperature and high pressure area includes: Controlling the inner cell of the lithium battery as a source boundary; Controlling the outer shell of the lithium battery as a target boundary; Controlling the expansion of the inner battery core to directly act on the outer shell; Controlling the housing as a boundary constraint for volume expansion of the lithium battery; Obtaining a relationship between the volume of the cube and the temperature during the first future time period; The output power of the lithium battery is dynamically adjusted according to the change relationship.

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