Temperature measuring circuit board, temperature measuring device and temperature measuring system of needle bed type chemical component storage cabinet

Abstract

The present application relates to the technical field of lithium battery equipment, and discloses a temperature measuring circuit board, a temperature measuring device and a temperature measuring system of a needle bed type formation and component distribution cabinet, wherein a plurality of infrared sensors are connected with a computing circuit through a carrier plate, the plurality of infrared sensors are arranged in an array, a plurality of needle avoidance holes are arranged around each infrared sensor, the infrared sensor and the plurality of needle avoidance holes form a temperature detection area, the infrared sensor is used for detecting the surface temperature of a lithium battery corresponding to the plurality of needle avoidance holes, the computing circuit, an audible and visual alarm, a total controller and an upper computer are all connected with a middle computer, the total controller is connected with a mechanical hand, and the mechanical hand is connected with a fire-fighting water tank.The temperature measuring circuit board and the temperature measuring device can greatly reduce the volume of the detection equipment, improve the temperature detection speed, make the detection more accurate and faster, and the temperature measuring system can greatly improve the safety of lithium battery production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium battery equipment, in particular to a temperature measuring circuit board, a temperature measuring device and a temperature measuring system of a needle bed type formation and capacity distribution cabinet. BACKGROUND

[0002] The formation and capacity distribution needle bed is a main equipment in the later stage of lithium battery production. In the working process, the battery will continuously emit heat, and it is necessary to continuously dissipate heat and detect the temperature of the battery in the whole process, so as to control the temperature of the environment around all batteries within a reasonable range. If temperature abnormalities occur, they need to be handled in a timely manner.

[0003] The existing measurement method is: 1. Multiple (usually 2-4) temperature sensors (usually various types of thermocouples) are arranged in the internal area of the storage location, and the average value is calculated to estimate the ambient temperature in the storage location area. This temperature measurement method measures the position not near the battery, and the temperature measurement is through air as the medium, so the measurement data has a lag, and therefore cannot accurately reflect the temperature of the battery, and can only roughly measure the air temperature in the storage location area, and can only be used for fire alarm detection after the battery appears abnormal and causes high temperature; 2. Temperature sensors are arranged side by side beside each needle, and the temperature sensors are directly in contact with the surface of the lithium battery. This method measures faster than the first method, but the measurement accuracy is affected by the contact degree of the sensor and the surface of the lithium battery, and there is an error possibility. In addition, this method requires one temperature sensor for each battery, and the temperature sensor occupies a certain space, and the independent temperature sensor has a high cost, so it is usually used on large square shells (such as 71173207 specifications) batteries, and usually there are 24-36 batteries in each storage location area.

[0004] The existing detection scheme in the industry has problems such as untimely temperature measurement, inaccurate measurement value, and dead angle in the measurement range.

[0005] In the production of cylindrical lithium batteries, there is no mature and reliable temperature measurement and monitoring method for the needle bed type formation and capacity distribution cabinet in the industry. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, and to provide a temperature measuring circuit board for a needle bed type formation and capacity distribution cabinet.

[0007] The present application also provides a temperature measuring device for a needle bed type formation and capacity distribution cabinet.

[0008] The present application also provides a temperature measuring system for a needle bed type formation and capacity distribution cabinet.

[0009] The application is achieved by the following technical solutions: a temperature measurement circuit board applied to a needle bed type chemical composition storage cabinet, comprising a carrier plate, a calculation circuit and a plurality of infrared sensors, the plurality of infrared sensors are connected with the calculation circuit through the carrier plate, the plurality of infrared sensors are arranged in an array, a plurality of needle avoiding holes are arranged around each infrared sensor, the infrared sensor and the plurality of needle avoiding holes form a temperature detection area, and the infrared sensor is used for detecting the surface temperature of a lithium battery corresponding to the plurality of needle avoiding holes. The temperature measurement circuit board can greatly reduce the volume of the detection equipment and improve the accuracy and speed of temperature detection.

[0010] In a more preferred selection, the carrier plate is provided with first air holes located on both sides of the infrared sensor. The first air holes can realize ventilation of the storage area, and can reduce the temperature of the lithium battery during charging and discharging.

[0011] In a more preferred selection, the carrier plate is provided with second air holes located between adjacent two temperature detection areas. The second air holes can realize ventilation of the storage area, and can reduce the temperature of the lithium battery during charging and discharging.

[0012] In a more preferred selection, the calculation circuit is provided with a power supply interface and a communication interface.

[0013] A temperature measurement device applied to a needle bed type chemical composition storage cabinet, comprising a temperature measurement frame, a floating support frame, a support spring, a temperature measurement mounting frame, a temperature measurement module and a battery height limiting column, the temperature measurement frame is provided with a plurality of storage areas, the temperature measurement mounting frame and the floating support frame are slidably installed in the storage area, the upper inner wall of the storage area is connected with the top of the temperature measurement mounting frame through a gas cylinder, the temperature measurement module is installed at the bottom of the temperature measurement mounting frame, the battery height limiting column is installed at the top of the floating support frame and corresponds to the cylinder shaft of the gas cylinder, and the two ends of the support spring are respectively in abutment with the bottom of the floating support frame and the lower inner wall of the storage area, and the temperature measurement module is a temperature measurement circuit board applied to a needle bed type chemical composition storage cabinet. The temperature measurement device can realize no dead angle temperature measurement of a plurality of lithium batteries in the battery tray and automatic pressing and opening of the lithium batteries.

[0014] In a more preferred selection, the temperature measurement frame comprises an optical axis, a storage base and a support rod, the storage bases are connected through the support rod, and adjacent two storage bases form a storage area, and the optical axis passes through the storage area, the floating support frame and the support spring. The temperature measurement frame can separate a plurality of battery trays, and improve the safety of the lithium batteries during production.

[0015] More preferably, the upper floating limiting column is installed at the lower inner wall of the storage area, and the upper end of the upper floating limiting column is in sliding connection with the upper end of the floating support frame, and the upper end of the upper floating limiting column limits the floating support frame.

[0016] More preferably, the lower floating limiting column is installed at the lower inner wall of the storage area, and the lower floating limiting column limits the floating support frame.

[0017] More preferably, the upper ejector disc mounting frame is slidably installed at the storage area, the cylinder shaft of the air cylinder is connected with the top of the upper ejector disc mounting frame, and the temperature measuring mounting frame is installed at the bottom of the upper ejector disc mounting frame.

[0018] A temperature measuring system applied to a needle bed type chemical formation and component storage cabinet comprises a temperature measuring module, a middle host, an air cylinder, an audible and visual alarm, an upper host, a total controller, a mechanical hand and a fire water tank, wherein the temperature measuring module, the air cylinder, the audible and visual alarm, the total controller and the upper host are connected with the middle host, the total controller is connected with the mechanical hand, the mechanical hand is connected with the fire water tank, and the temperature measuring module is a temperature measuring circuit board applied to the needle bed type chemical formation and component storage cabinet.

[0019] Compared with the prior art, the temperature measuring system has the following advantages and beneficial effects:

[0020] The temperature measuring circuit board and the temperature measuring device of the needle bed type chemical formation and component storage cabinet can greatly reduce the volume of the equipment, one infrared sensor can detect the temperature of multiple lithium batteries at the same time, and the temperature detection accuracy is much higher than that of the method of installing one temperature detection probe in one storage area, the temperature detection speed of the infrared sensor is more accurate and faster, and the technical problems of the prior art, such as the temperature detection speed is not timely, the measurement value of the lithium battery is not accurate, and the measurement range of the lithium battery has a dead angle, are solved, and the temperature measuring system can greatly improve the safety of lithium battery production. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic view of a temperature measuring circuit board applied to a needle bed type chemical formation and component storage cabinet of the present application;

[0022] Figure 2 is a schematic view of a temperature measuring circuit board applied to a needle bed type chemical formation and component storage cabinet of the present application;

[0023] Figure 3It is a use schematic view of a temperature measuring circuit board applied to a needle bed type chemical composition container cabinet according to the present application;

[0024] Figure 4 It is a schematic view of a temperature measuring device applied to a needle bed type chemical composition container cabinet according to the present application at a lithium battery test point position;

[0025] Figure 5 It is a front view of a temperature measuring module frame of a temperature measuring device applied to a needle bed type chemical composition container cabinet according to the present application;

[0026] Figure 6 It is a side view of a temperature measuring module frame of a temperature measuring device applied to a needle bed type chemical composition container cabinet according to the present application;

[0027] Figure 7 It is a side view of a temperature measuring module frame (including a battery tray) of a temperature measuring device applied to a needle bed type chemical composition container cabinet according to the present application;

[0028] Figure 8 It is a front view of a temperature measuring module frame (including a battery tray) of a temperature measuring device applied to a needle bed type chemical composition container cabinet according to the present application;

[0029] Figure 9 It is a schematic view of a floating support frame of a temperature measuring device applied to a needle bed type chemical composition container cabinet according to the present application;

[0030] Figure 10 It is a flow chart of a temperature measuring system applied to a needle bed type chemical composition container cabinet according to the present application;

[0031] Figure 11 It is a schematic view of a temperature measuring device (popped-up state) applied to a needle bed type chemical composition container cabinet according to the present application;

[0032] Figure 12 It is Figure 11 A local enlarged schematic view at A;

[0033] Figure 13 It is a schematic view of a temperature measuring system (pressed-down state) applied to a needle bed type chemical composition container cabinet according to the present application;

[0034] Figure 14 It is Figure 13 A local enlarged schematic view at B;

[0035] The components in the attached diagram are labeled as follows: 1-Temperature measuring circuit board; 11-Infrared sensor; 111-Infrared light; 12-Calculation circuit; 121-Power interface; 122-Communication interface; 13-Carrier board; 131-First ventilation hole; 132-Second ventilation hole; 133-Ejector pin clearance hole; 134-Mounting screw through hole; 2-Cylinder; 201-Cylinder shaft; 3-Lower ejector pin; 4-Lithium battery; 401-Infrared detection point; 5-Battery tray; 6-Temperature measuring frame; 601-Support rod; 602-Optical axis; 603-Storage base; 604-Upper ejector pin mounting bracket; 605-Floating support frame; 6051-Guide strip; 606-Support spring; 607-Temperature measuring mounting bracket; 608-Floating upper limit post; 609-Battery height limit post; 610-Floating lower limit post; 7-Upper ejector pin. Detailed Implementation

[0036] The invention's objective will be further described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described in detail here, but the implementation of the invention is not limited to the following embodiments.

[0037] like Figures 1-3 As shown, the temperature measuring circuit board 1 of the needle bed type chemical dispensing cabinet includes forty infrared sensors 11, a carrier board 13, and a computing circuit 12. The forty infrared sensors 11 are arranged in a matrix on the carrier board 13, with eight infrared sensors 11 in each row and five infrared sensors 11 in each column. The carrier board 13 contains circuitry, and the forty infrared sensors 11 are connected to the computing circuit 12 through the circuitry within the carrier board 13. A row of pin-avoiding holes 133 is provided on the upper and lower sides of each row of infrared sensors 11. Each infrared sensor 11 is located at the center of four adjacent pin-avoiding holes 133. A first ventilation hole 131 is provided on the left and right sides of each infrared sensor 11. One infrared sensor 11 and four pin-avoiding holes 133 form a temperature measuring area. A second ventilation hole 132 is provided between two adjacent temperature measuring areas in the same row and column. The computing circuit 12 is provided with a power interface 121 and a communication interface 122.

[0038] Infrared sensor 11 is used to detect the surface temperature of lithium battery 4, and can simultaneously detect the surface temperature of four lithium batteries 4 without contact. Figure 5 As shown. The carrier plate 13 is used to evenly distribute the infrared sensors 11 and connect them to the computing circuit 12. The computing circuit 12 is used to convert the signals from the infrared sensors 11 into temperature values ​​and upload them to the central computer. The ejector pin clearance hole 133 allows the upper ejector pin 7 to pass through. The first ventilation hole 131 and the second ventilation hole 132 are used for ventilation within the storage area.

[0039] like Figures 6-9As shown, a temperature measuring device applied to a needle bed type chemical component distribution cabinet comprises a temperature measuring frame 6, four upper contact pin disc mounting frames 604, four floating support frames 605, sixteen supporting springs 606, four temperature measuring mounting frames 607, four temperature measuring circuit boards 1, eight air cylinders 2, eight battery height limiting columns 609, sixteen floating upper limiting columns 608 and eight floating lower limiting columns 610. The temperature measuring frame 6 comprises four optical shafts 602, five library location bases 603 and four supporting rods 601. The five library location bases 603 are arranged from top to bottom, the spacing between the five library location bases 603 is the same, and the two sides of the five library location bases 603 are respectively fixedly connected by two supporting rods 601. The four optical shafts 602 pass through the five library location bases 603 in turn, and the four corners of the five library location bases 603 are fixedly connected with the four optical shafts 602. Two adjacent library location bases 603 form a library location area, and the optical shafts 602 in the library location area pass through the four linear bearings of the upper contact pin disc mounting frame 604 and the four linear bearings of the floating support frame 605 in turn. The left and right ends of the bottom of the library location base 603 above the library location area are fixedly connected with two air cylinders 2, and the cylinder shafts 201 of the two air cylinders 2 are fixedly connected with the left and right ends of the top of the upper contact pin disc mounting frame 604. A temperature measuring mounting frame 607 is installed at the bottom of the upper contact pin disc mounting frame 604, and a temperature measuring circuit board 1 is installed at the bottom of the temperature measuring mounting frame 607. Four guide strips 6051 are arranged in the floating support frame 605, thereby forming two tray positions, so as to facilitate the pushing of the battery tray 5 into the floating support frame 605. Two battery height limiting columns 609 are located outside the two battery trays 5 and are fixedly installed at the top of the floating support frame 605. The upper ends of the two battery height limiting columns 609 can be pressed downward by the bottom of the upper contact pin disc mounting frame 604 (that is, the battery height limiting columns 609 are indirectly pressed by the cylinder shafts 201 of the air cylinders 2). Four supporting springs 606 are sleeved on the four optical shafts 602 in each library location area and are located between the bottom of the floating support frame 605 and the top of the library location base 603 below the library location area. The four supporting springs 606 are pressed downward by the floating support frame 605. Four floating upper limiting columns 608 are fixedly installed at the two ends of the library location base 603 below the library location area, the floating support frame 605 can slide relative to the four floating upper limiting columns 608, and the upper ends of the four floating upper limiting columns 608 can limit the floating support frame 605. Two floating lower limiting columns 610 are also installed at the top of the library location base 603 below the library location area and are located between the two floating upper limiting columns 608 at the same end.

[0040] The temperature measuring frame 6 is used to place the battery tray 5 in layers, forming multiple storage area, improve the safety of lithium battery 4 in the formation process. The upper pin disc mounting frame 604 is used to install the upper pin 7, and the upper pin 7 is evenly distributed. The floating support frame 605 is used to support the battery tray 5. The support spring 606 plays a buffering role, and the floating support frame 605 resets when it is not under pressure. The temperature measuring mounting frame 607 is used to install the fixed temperature measuring circuit board 1. The temperature measuring circuit board 1 is used to measure the surface temperature of the lithium battery 4 in the battery tray 5, and convert the temperature into temperature value and upload to the intermediate machine. The cylinder 2 is used to push the upper pin disc mounting frame 604 to move downward along the optical axis 602, so that the upper pin 7 of the upper pin disc mounting frame 604 and the lower pin 3 of the floating support frame 605 respectively contact the positive and negative poles of the lithium battery 4. The battery height limiting column 609 is used to transmit the pressure of the upper pin disc mounting frame 604 to the floating support frame 605, while avoiding the lithium battery 4 from being crushed. The floating upper limiting column 608 is a floating upper limiting hexagonal stud, which is used to limit the upward movement height of the floating support frame 605 along the optical axis 602. The floating lower limiting column 610 is a floating lower limiting hexagonal stud, which is used to limit the downward movement depth of the floating support frame 605 along the optical axis 602, avoiding crushing the lower pin 3. The optical axis 602 plays a guiding role in the movement of the upper pin disc mounting frame 604 and the floating support frame 605. The storage base 603 plays a supporting role for the battery tray 5 and the cylinder 2. The support rod 601 is used to fix the storage base 603, so that a certain distance is formed between the storage bases 603.

[0041] The process of pressing the battery tray 5 in the temperature measuring device is as follows:

[0042] When the cylinder shaft 201 of the cylinder 2 extends downward, the cylinder 2 pushes the upper pin disc mounting frame 604 to move downward along the optical axis 602, and the bottom of the upper pin disc mounting frame 604 contacts the top of the battery height limiting column 609, which pushes the floating support frame 605 to move downward along the optical axis 602, i.e. the lithium battery 4 in the battery tray 5 moves downward.

[0043] The cylinder shaft 201 of the cylinder 2 continues to extend downward, the top end of the lithium battery 4 keeps in contact with the upper pin 7 of the upper pin disc mounting frame 604, and the bottom end of the lithium battery 4 keeps in contact with the lower pin 3 on the floating support frame 605, completing the pressing action. At this time, the infrared sensor 11 is located at the center of the adjacent four lithium batteries 4, and each infrared sensor 11 can detect the surface temperature of four lithium batteries 4 at the same time.

[0044] As Figure 10As shown, the temperature measurement system of the pin bed type charging, discharging and capacity testing cabinet includes a set of charging, discharging and capacity testing power supply module, four storage positions, a middle computer, an audible and visual alarm, a host computer, a general controller, a manipulator and a fire fighting water tank. Each storage position is equipped with a temperature measurement circuit board 1 and sixteen charging, discharging and capacity testing circuit boards. Each charging, discharging and capacity testing circuit board can be connected to ten lithium batteries simultaneously (that is, each charging, discharging and capacity testing circuit board has ten channels). The charging, discharging and capacity testing power supply module is respectively connected to the sixteen charging, discharging and capacity testing circuit boards. The middle computer is respectively connected to the four temperature measurement circuit boards 1, the charging, discharging and capacity testing power supply module, the audible and visual alarm, the host computer, the cylinder 2 and the general controller. The general controller is connected to the manipulator, and the manipulator is connected to the fire fighting water tank.

[0045] The charging, discharging and capacity testing power supply module belongs to the prior art and is used for charging and discharging lithium batteries. The charging, discharging and capacity testing power supply module has 1280 channels and can charge and discharge 1280 lithium batteries simultaneously. In this embodiment, only 640 of these channels are used. The temperature measurement circuit board 1 is used to detect the surface temperature of the lithium battery 4 and convert the temperature of the lithium battery 4 into a numerical value and upload it to the middle computer. The charging, discharging and capacity testing circuit board can be purchased in the existing market and is used to connect the positive and negative electrodes of the lithium battery 4 and transmit them to the charging, discharging and capacity testing power supply module. The middle computer is a single-chip microcomputer, which is used to receive the signal of the temperature measurement circuit board 1, control the charging and discharging of the charging, discharging and capacity testing power supply module, the state of the audible and visual alarm, and the movement state of the cylinder 2, and transmit information with the host computer and the general controller to complete the instructions of the host computer and the general controller. The host computer is a computer, which is used to analyze and process data and display it to the operator, and the operator issues instructions to the middle computer. The general controller is a server, which is used to control the linkage of various devices on the production line. The manipulator is used to carry the battery tray 5. The fire fighting water tank is used to isolate and extinguish the lithium battery 4 with abnormalities.

[0046] The working principle of the temperature measurement system is described as follows:

[0047] As Figures 11-14 shown, when the battery tray 5 filled with lithium batteries 4 is pushed into the floating support frame 605 in the storage position area, an operator manually operates the push-pull valve to control the cylinder shaft 201 of the cylinder 2 to extend downward. The cylinder shaft 201 pushes the upper push pins 7 on the upper push pin plate mounting frame 604 to press downward as a whole. The upper push pin plate mounting frame 604 pushes the floating support frame 605 to press downward through the battery height limiting column 609. Under the support of the support spring 606, the upper push pins 7 keep in contact with the top of the lithium battery 4, and the lower push pins 3 on the floating support frame 605 keep in contact with the lower end of the lithium battery 4. At the same time, the infrared sensors 11 on the temperature measurement circuit board 1 are located at the center of every four batteries in the battery tray 5 and start to measure the temperature of the nearby four lithium batteries 4.

[0048] When the infrared sensor 11 detects that the surface temperature of the lithium battery 4 is abnormal, the infrared sensor 11 transmits information to the central machine through the calculation circuit 12, and instructs the formation and component power supply module to stop outputting current and voltage to the lithium battery 4, and simultaneously disconnects the air path. A reset spring is arranged in the top pin disc mounting frame 604, which automatically moves upward under the action of the elastic force of the reset spring. The central machine issues an instruction to the sound and light alarm to alarm, and the battery tray 5 containing the abnormal lithium battery is taken away by artificial or controlled by the general controller.

[0049] The temperature measurement circuit board 1 is provided with infrared sensors 11 at positions corresponding to the centers of every four adjacent batteries, which can simultaneously receive the infrared signals emitted by the four lithium batteries. The infrared signals are converted into temperature values that can be displayed on the screen through internal circuits and algorithm software (the algorithm software is prior art). The highest temperature value among the received temperature values of the four lithium batteries is taken as the temperature output of the detection point. The array type integrated infrared sensor 11 on the temperature measurement circuit board 1 greatly reduces the volume of the detection equipment, and each infrared sensor simultaneously detects the surface temperature of four lithium batteries, so the accuracy of temperature detection is much higher than the method of installing one temperature detection probe in each library location area. For example, there are a total of 160 batteries in each library location area of the batch production equipment. According to the existing temperature detection method, one to five thermistors are installed in each library location, and the battery temperature is indirectly detected through air as the medium. In the present embodiment, the infrared sensor 11 is used, so that the total number of temperature detection points of 160 batteries in one library location reaches 40, and the temperature is detected by infrared light. The infrared sensor 11 does not need air as the propagation medium when detecting infrared light, so that the temperature detection speed is more accurate and faster. The temperature detection speed of the thermistor needs 1-2 seconds to react to the temperature change of the medium, and the temperature error between the medium and the detection object is very large. If the pin bed is applied to the scene, the temperature error between the medium and the detection object can reach ±5 degrees Celsius. The temperature detection speed using the infrared sensor 11 is less than 50 milliseconds, because it is directly detected, and the error between the detected temperature and the actual temperature is only 0.5 degrees Celsius. The infrared sensor 11 of the temperature measurement circuit board 1 in the present embodiment realizes real-time monitoring and high-precision detection, so that the production process of the entire lithium battery 4 can be strictly monitored, and the safety of the lithium battery 4 production can be greatly improved by cooperating with the active fire fighting strategy.

[0050] The monitoring method of the temperature measurement system comprises the following steps:

[0051] Step S1, using infrared sensor to detect the temperature of lithium battery, voltage and current of lithium battery, temperature, voltage and current corresponding time data, get temperature data T, voltage data V and current data I. According to the shannon-nyquist sampling theorem, the optimal sampling rate is set for temperature data T, current data V and voltage data I. The sampling rate of temperature data T is 100 Hz, which meets the detection requirement of the maximum temperature rise rate of lithium battery 10 ℃ / s; The sampling rate of current data is 5 kHz, which can capture 100 μs transient change; The sampling rate of voltage data is 1 kHz, which covers the decomposition characteristic frequency of electrolyte.

[0052] Step S2, processing the temperature data T, voltage data V and current data I of step S1 to get temperature rise acceleration a(t), temperature rise rate u(t), voltage spectrum entropy H V , temperature-current phase difference R TI (τ) and current ripple coefficient γ. The temperature rise acceleration a(t) can be used as early warning of thermal runaway, the voltage spectrum entropy H V can reflect the stability of internal chemical reaction, the temperature-current phase difference R TI (τ) can judge the proportion of ohmic heat and reaction heat.

[0053] Step S201, based on the second derivative calculation, according to the temperature data T of step S1, the calculation formula of temperature rise acceleration a(t) is obtained:

[0054]

[0055] Wherein, T is the temperature data of lithium battery, t is the time series index, Δt is the temperature sampling time interval.

[0056] Step S202, according to the temperature data T of step S1, the temperature rise rate u(t) is calculated, and the calculation formula of temperature rise rate u(t) is

[0057] Step S203, based on the shannon entropy calculation of FFT (fast fourier transform), according to the voltage data of step S1, the voltage spectrum entropy H V is obtained, and the calculation formula of voltage spectrum entropy H V is as follows:

[0058]

[0059] Wherein,

[0060] Wherein, P(k) is the normalized power spectral density, the energy proportion of the kth frequency component; P(k) is the FFT spectrum amplitude, the fourier transform result of voltage signal; N is the FFT point number, default 1024 points.

[0061] Step S204, based on the peak position analysis of the cross-correlation function, the temperature-current phase difference R is calculated according to the temperature data and the current data of step S1 TI (τ), the temperature-current phase difference R TI (τ) is calculated by the formula

[0062]

[0063] Wherein, τ is the time delay, the phase difference of temperature and current change; N is the data window length, the number of sampling points contained in the sliding window; I is the current of the lithium battery.

[0064] Step S205, the current ripple coefficient is calculated by the current data of step S1, and the calculation formula of the current ripple coefficient is:

[0065] Wherein, I rms is the current effective value, the root mean square of the alternating component; I arg is the current average value.

[0066] Step S3, according to the temperature acceleration, voltage frequency spectrum entropy and temperature-current phase difference of step S2, first, the primary threshold value is judged, when the primary threshold value is in line with the standard, no measures are taken, when the primary threshold value is over standard, step S4 is executed;

[0067] The primary threshold value judgment process is: when the temperature data of step S1 is greater than 80℃ or the temperature rise rate of step S2 is greater than 5℃ / s, the III level response is started;

[0068] Step S4, according to the primary threshold value of step S3, the identification is carried out through the intermediate mode, and the lithium battery is identified as an abnormal state;

[0069] Step S41, an SVM (Support Vector Machine) classifier is constructed;

[0070] K(x i , x j )=exp(-γ||x i -x j || 2 ),

[0071] Wherein, γ is the kernel function parameter, the value is 0.5; (x i , x j ) represents the labeled training sample; / / · / / represents the Euclidean distance.

[0072] Step S42, input the temperature rise acceleration, voltage spectrum entropy and current ripple coefficient of step S2 into the SVM classifier of step S41 to obtain a kernel function value, the kernel function value is calculated by a decision function to obtain a score, and the lithium battery state is determined according to the score, the lithium battery state includes a normal state, an abnormal state and a critical state, and the decision function calculation formula is as follows:

[0073]

[0074] Wherein, k∈{normal state, abnormal state, critical state}, S is a feature vector set, K(x i , x j ) is a kernel function, is a dual variable of the kth class, y i is the original label of the ith feature vector, b k is the bias term of the kth class.

[0075] Step S421, input the sample x new =[1.2℃ / s 2 ,2.3,18%], and perform feature normalization on the temperature rise acceleration (1.2℃ / s 2 ), voltage spectrum entropy (2.3) and current ripple coefficient (18%) to obtain normalized feature values, and the calculation formula of feature normalization is Wherein, μ is the feature mean, and σ is the standard deviation.

[0076] Original characteristic value Temperature rise acceleration (°C / s 2 )]]> Voltage spectrum entropy Current ripple coefficient (%) sample x new ]] 1.2 2.3 18 x' i ]] 0.8 0.6 1.5

[0077] Step S422, construct a feature vector from the normalized feature values; for example: x i =[0.8,0.6,1.5].

[0078] Step S423, substitute the feature vector of step S422 into the SVM classifier of step S41 to calculate the score, and divide the battery state according to the score, the battery state includes a normal state, an abnormal state and a critical state. For example:

[0079] (1) Kernel function calculation:

[0080] Feature vector 1 (normal class): x1=[0.5,0.2,1.0];

[0081] K1=exp(-0.5×||0.8-0.5|| 2 +||0.6-0.2|| 2 +||1.5-1.0|| 2 )=e -0.5×0.5 ≈0.6065;

[0082] Feature vector 2 (abnormal class): x2 = [1.0, 1.5, 2.0];

[0083] K2 = exp(-0.5 x ||0.8 - 1.0||2 2 + ||1.5 - 2.0||2 2 ) = e 2 -0.5×1.14 ≈ 0.5698;

[0084] (2) Score calculation (assuming weights):

[0085] Score for normal state: 0.6 x 0.6065 + 0.4 x 0.5698 + 0.2 = 0.854;

[0086] Score for abnormal state: 0.8 x 0.5698 - 0.3 = 0.1558;

[0087] Score for critical state: 0.5 x 0.6065 + 0.6 x 0.5698 = 0.7323;

[0088] Take the highest score of the three lithium battery states as the output result: normal state (highest score is 0.854).

[0089] Step S5, use the advanced prediction model to predict the future 60-second temperature change trend for the lithium battery identified as an abnormal state, and when the predicted temperature rise > 3°C / s, perform level III emergency treatment (cut off the charging and discharging of the lithium battery and open the fire-fighting water tank and wait for the mechanical hand to carry the lithium battery); otherwise, level II continuous detection (enhance temperature data, voltage data and current data collection and manual review).

[0090] Three-level risk determination and measures list

[0091] Risk level Judgment condition Disposal measure Class I Single parameter exceeds the standard Acousto-optic alarm + data review Class II Double parameter abnormality + predicted trend deterioration Cut off the charging and discharging circuit Class III Multiple parameters meet the characteristics of thermal runaway Start the safety removal program

[0092] According to the temperature data T, voltage data V and current data I of step S1, the predicted temperature rise is obtained by prediction through the advanced prediction model. The calculation formula of the early warning time window (30-120s) and the predicted temperature rise is as follows:

[0093]

[0094] Where, f LSTM is a deep learning model that maps historical data to future temperature, T t-k：t is the temperature data from time t-k to t, I t-k：t is the current data from time t-k to t, and V t-k：tFor the voltage data from time t-k:t to t, T is the temperature data of the lithium battery, Delta t is the early warning time length, and the default is 60s; k is the length of historical data, and the input sequence length is 30 points by default.

[0095] The performance verification data of the temperature measurement system are as follows:

[0096]

[0097]

[0098] As can be seen from the above data, the temperature measurement system realizes a technological revolution in the three core indicators of precision (±0.3℃), reliability (100% success rate of disposal), and foresight (68 seconds of early warning), not only comprehensively surpassing the existing industry standards, but also filling the technical gap of thermal runaway early warning, providing a new generation of high-reliability and safety solution for the field of lithium battery applications, and is expected to become a mandatory safety standard for scenarios such as power batteries and energy storage power stations.

[0099] The above specific embodiments are preferred embodiments of the present application and cannot limit the present application, and any changes or other equivalent replacement methods that do not deviate from the technical solutions of the present application are included in the protection scope of the present application.

Claims

1. A temperature measuring device for a needle bed type chemical component dispensing cabinet, characterized in that: The temperature measurement frame (6) is provided with a plurality of storage location areas, the temperature measurement mounting frame (607) and the floating support frame (605) are slidably installed in the storage location area, the upper inner wall of the storage location area is connected with the top of the temperature measurement mounting frame (607) through the air cylinder (2), the temperature measurement circuit board is installed at the bottom of the temperature measurement mounting frame (607), the battery height limiting column (609) is installed at the top of the floating support frame (605) and corresponds to the cylinder shaft (201) of the air cylinder (2), and the two ends of the supporting spring (606) respectively abut against the bottom of the floating support frame (605) and the lower inner wall of the storage location area. The temperature measurement circuit board comprises a carrier plate (13), a calculation circuit (12) and a plurality of infrared sensors (11), the plurality of infrared sensors (11) are connected with the calculation circuit (12) through the carrier plate (13), the plurality of infrared sensors (11) are arranged in an array, a plurality of contact pin avoidance holes (133) are arranged around each infrared sensor (11), the infrared sensor (11) and the plurality of contact pin avoidance holes (133) form a temperature detection area, and the infrared sensor (11) is used for detecting the surface temperature of a lithium battery (4) corresponding to the plurality of contact pin avoidance holes (133).

2. The temperature measuring device of the needle bed type chemical preparation and component distribution cabinet according to claim 1, characterized in that: The temperature measurement frame (6) comprises an optical axis (602), a storage location base (603) and a support rod (601), the storage location bases (603) are connected through the support rod (601), two adjacent storage location bases (603) form a storage location area, and the optical axis (602) penetrates through the storage location area, the floating support frame (605) and the supporting spring (606).

3. The temperature measuring device of the needle bed type chemical preparation and component distribution cabinet according to claim 1, characterized in that: The floating upper limiting column (608) is further included, the lower end of the floating upper limiting column (608) is installed on the lower inner wall of the storage location area, the upper end of the floating upper limiting column (608) is slidably connected with the floating support frame (605), and the upper end of the floating upper limiting column (608) limits the floating support frame (605).

4. The temperature measuring device of the needle bed type chemical preparation and component distribution cabinet according to claim 1, characterized in that: The floating lower limiting column (610) is further included, the floating lower limiting column (610) is installed on the lower inner wall of the storage location area, and the floating lower limiting column (610) limits the floating support frame (605).

5. The temperature measuring device of the needle bed type chemical component dispensing cabinet according to claim 1, characterized in that: The upper contact pin disc mounting frame (604) is further included, the upper contact pin disc mounting frame (604) is slidably installed in the storage location area, the cylinder shaft (201) of the air cylinder (2) is connected with the top of the upper contact pin disc mounting frame (604), and the temperature measurement mounting frame (607) is installed at the bottom of the upper contact pin disc mounting frame (604).

6. The temperature measuring device of the needle bed type chemical component cabinet according to claim 1, characterized in that: The carrier plate (13) is provided with a first air hole (131), and the first air hole (131) is located on both sides of the infrared sensor (11).

7. The temperature measuring device of the needle bed type chemical preparation and component distribution cabinet according to claim 1, characterized in that: The carrier plate (13) is provided with a second air-permeable hole (132) located between two adjacent temperature detection areas.

8. The temperature measuring device of the needle bed type chemical component cabinet according to claim 1, characterized in that: The calculation circuit (12) is provided with a power supply interface (121) and a communication interface (122).

Images