CN210487936U

CN210487936U - On-line detection system for single power battery

Info

Publication number: CN210487936U
Application number: CN201921385901.1U
Authority: CN
Inventors: 王莉; 叶岍; 刘静茹; 曹玉龙; 娄本相; 孔国红
Original assignee: Tianjin Qmind Technology Ltd; Tianjin Agricultural University
Current assignee: Suzhou Qiwu Intelligent Equipment Co., Ltd
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2020-05-08
Anticipated expiration: 2029-08-23

Abstract

The utility model relates to a monomer power battery on-line measuring system. Monomer power battery on-line measuring system includes: host computer PC, the PLC who is connected with host computer PC, photoelectric sensor, jacking cylinder, the cylinder that is connected with PLC alone, transfer slip table cylinder, power cylinder motor, touch-sensitive screen, sweep a yard rifle, internal resistance tester, open circuit voltage tester that are connected with host computer PC alone. The upper computer PC provides rich display for field operators of the battery production line and also completes analysis processing on data acquired by the tester; and the PLC executes the tasks distributed from the upper computer PC after receiving the command from the upper computer. The utility model has the advantages that: the on-line detection of the internal resistance and the open-circuit voltage of the single power battery is realized.

Description

On-line detection system for single power battery

The technical field is as follows:

the utility model relates to a lithium ion battery manufacturing process. Further relates to a single power battery online detection system.

Background art:

because of the characteristics of high specific energy (power) density, long service life, high use safety and the like, the lithium ion battery becomes the most main power source of the electric automobile. The lithium ion power battery meets three basic requirements of long endurance time, excellent service life and safety and reliability, and the electric vehicle can be marketed. The consistency problem of the lithium ion battery directly or indirectly affects the three basic problems and becomes one of the most basic problems in all battery application technologies, and the problem is successfully solved, so that the service life of a battery pack can be prolonged, and safety problems such as overcharge and overdischarge caused by battery inconsistency can be effectively reduced.

Since the single power battery cannot meet the requirements of high power and high capacity required in practical application, it is better to combine a plurality of batteries to form a battery pack. Although the performance parameters of the multiple batteries combined in the battery pack are close to each other through the sorting threshold of the production line, there still exist some differences due to the influence of many factors, and the differences are gradually amplified in the subsequent cycle use, so that the battery pack fails. It is therefore necessary to classify batteries with very similar properties, so that the properties of the assembled battery can be optimized. Thus, the battery pack has obvious effect of improving the overall performance of the battery pack, and can reduce the waste of unnecessary materials and even reduce the environmental pollution. In order to improve the overall function of the battery pack, the difference between the single batteries is reduced, that is, the inconsistency of the single batteries is reduced as much as possible.

Currently, most battery factories use "dominant" indicators of reactive battery performance, such as capacity, ACR, and OCV, to sort batteries based on cost and yield considerations. The research on a single battery performance test system on a battery production line is strengthened, and the consistency of the single batteries can be improved to a great extent. The single battery performance testing system on the battery production line can acquire the values of the internal resistance and open-circuit voltage performance parameters of the single battery in real time, and meanwhile, the charging and discharging curve parameters of production line software are called, the testing parameters are stored, and the battery is comprehensively analyzed. Particularly, the special function of the online test of the battery performance parameters enables the online test method to have the advantages that the online test method is different from the off-line test method generally adopted in the market, and the corresponding values of the internal resistance and the open-circuit voltage of each single battery can be obtained more quickly and accurately, so that the service level of each single battery can be judged more accurately, and the corresponding single battery classification can be realized. The single power battery performance detection system is a necessary process for battery production, and is used for collecting and processing various performance index data of the battery, determining a battery sorting strategy and further deciding battery classification so as to meet the requirement of ensuring a user. The development of the single power battery detection system is particularly important under the influence and restriction of various factors such as the performance of raw materials, the structure of electrode materials, the production process and the like.

Battery PACK requires that the cells have a high degree of consistency (capacity, internal resistance, voltage, discharge curve, lifetime). At present, the standards for evaluating the consistency of the lithium ion power battery mainly comprise capacity, internal resistance and open-circuit voltage. The common sorting method is to collect the capacity, open-circuit voltage and internal resistance of the battery in full state of the lithium ion single battery as basic data, and to classify and group the battery. However, after the batteries are subjected to capacity grading screening by the small current process, a lot of batteries with low open-circuit voltage and more obvious electrical property difference still appear in the use process of the batteries which are matched and assembled, so that an assembled module and even the whole battery pack fail due to the abnormality of individual single batteries. Therefore, before the power batteries are grouped, the single batteries must be screened to remove the monomers with large differences, and consistent and good battery packs are selected. The internal resistance and the open-circuit voltage of the battery are key parameters, and online monitoring is very necessary.

Battery internal resistance: when the battery works, the resistance to the current flowing through the battery is called the internal resistance of the battery. Including ohmic and polarization internal resistances. When the battery is in discharge operation, the voltage is reduced along with the increase of the internal resistance of the battery, and the discharge time length is correspondingly shortened. The raw materials, the manufacturing process and the structural composition of the battery are main factors influencing the internal resistance of the battery. The internal resistance is a key factor for evaluating the performance of the single battery.

Open circuit voltage and operating voltage: the open circuit voltage refers to the voltage of the positive electrode and the negative electrode of the battery in a non-operating state, i.e., the potential difference between the positive electrode terminal and the negative electrode terminal of the battery when no current flows. Detecting the open circuit voltage of a battery is an important means of determining the state of charge of the battery. When a current flows under an operating condition, the potential difference between the positive electrode and the negative electrode of the battery is referred to as an operating voltage, also referred to as a terminal voltage. In the battery discharge operation state, when current flows inside the battery, a voltage drop due to the internal resistance of the battery must be overcome, so the operating voltage is lower than the open circuit voltage.

The invention content is as follows:

the utility model provides a to battery internal resistance, open circuit voltage's monomer power battery on-line measuring system. The specific technical scheme is as follows:

monomer power battery on-line measuring system includes: the device comprises an upper computer PC, a PLC connected with the upper computer PC, a photoelectric sensor, a jacking cylinder, a blocking cylinder, a transfer sliding table cylinder, a power roller motor, a touch screen, a code scanning gun, an internal resistance tester (12) and an open-circuit voltage tester (13), wherein the photoelectric sensor, the jacking cylinder, the blocking cylinder, the transfer sliding table cylinder, the power roller motor, the touch screen and the code scanning gun are independently connected with the PLC. The upper computer PC provides rich display for field operators of the battery production line and also completes analysis processing on data acquired by the tester; and the PLC executes the tasks distributed from the upper computer PC after receiving the command from the upper computer PC.

The utility model has the advantages that:

the on-line detection of the internal resistance and the open-circuit voltage of the single power battery is realized; the battery barcode scanning tracing function is realized, and the battery information can be known in real time; the usability of the system is improved, and the analysis of the battery performance is facilitated.

Description of the drawings:

fig. 1 is a system structure diagram of the present invention. In the figure, an internal resistance tester is used for collecting internal resistance parameters; the open-circuit voltage tester is used for collecting open-circuit voltage parameters; the photoelectric sensor is used for detecting a battery tray position signal; a cylinder: the battery tray is fixed by the blocking cylinder, and the battery is jacked to a measuring position by the jacking cylinder; the motor is used as a power source to drive the power roller; the touch screen is interacted with the PLC, receives information fed back from a field, drives an operation instruction and coordinates execution of a corresponding actuator; sweep a yard rifle: acquiring corresponding tray information and binding information of batteries in the tray; the PC processes the data collected by the test instrument; the PLC realizes interaction with the upper computer PC, and then a decision scheme is obtained to drive the corresponding actuating mechanism to act.

FIG. 2 is a flowchart of OCV test operation in an example embodiment.

FIG. 3 is a flow chart of PLC operation in the embodiment.

Fig. 4 is a diagram of a field device in an embodiment. In the drawings, a photoelectric detection sensor is used for detecting whether a battery tray reaches a specified position; the blocking cylinder is used for fixing the tray; the power roller is used for conveying the battery tray.

Fig. 5 is a front view of fig. 4.

Fig. 6 is a partially enlarged view of a portion a in fig. 5.

The specific implementation mode is as follows:

example (b):

The system adopts a HIOKI daily tester to acquire internal resistance data, and an Agilent tester 34980A to acquire OCV data, so that high-precision measurement is realized. In the voltage measurement of BT3562, the minimum resolution can reach 10 muV, and the precision can reach 0.01 percent, thereby ensuring that the measured data is accurate and reliable in the precision range required by the system.

The internal state of the battery may change in a short time, and if the detection system lags behind, data cannot be collected in time, so that whether the data can reflect the performance of the battery cannot be guaranteed, and the real-time performance of the detection system needs to be guaranteed.

The PLC is connected with the upper computer PC through a network cable by taking Mitsubishi q13 udeh as a main controller to realize interaction with the upper computer PC, so that a decision scheme is obtained and a corresponding execution mechanism is driven to act; communicating with a code scanning gun through a serial port to obtain corresponding tray information and binding information of batteries in the tray; receiving photoelectric sensor signals through an I/O port, and driving actuators such as cylinders and motors; the real production line condition is obtained by interaction between the internet access and the touch screen, and a specific control point can be controlled by the touch screen; and receiving information fed back from the site through a man-machine interaction interface operation panel, and driving and coordinating execution of corresponding actuators according to operation instructions.

The Mitsubishi GS touch screen is used as an operation interface, so that a user can conveniently carry out conventional operations, and in addition, the functions of real-time monitoring and recording of states, fault diagnosis and the like can be realized, and the operation is convenient, intuitive and quick; the operating panel adopts a DC24V button with a lamp to realize the functions of power-on, power-off, starting, emergency stop and reset respectively; an actuating mechanism of the system is formed by matching the cylinder with devices such as a battery tray and the like, so that corresponding driving instructions are realized; the battery performance parameter data acquisition of the test system is completed by a HIOKI daily BT3562 and Agilent 34980A tester; the sensor of the detection system consists of a cylinder magnetic switch and a photoelectric sensor, and is used for detecting and feeding back the position of the battery tray.

In order to better realize the system function, I/O ports of the PLC control unit need to be distributed, and the arrangement of the whole control sequence and the writing of related programs are facilitated. Firstly, reasonably planning a field control object, and according to a frame diagram and a design scheme of a system, clearly knowing that the control object of the system has the following 9 types, respectively: button signal, cylinder signal, sensor signal, tester signal, conveyer belt signal, relay signal, pilot lamp signal. Through the analysis of the on-site production line equipment, the detection system has 16 input points and 9 output points.

The PLC control program mainly comprises four functional modules, namely alarm information, information interaction, common processing and OCV operation, and the four modules work in a cooperative mode to complete all control functions of the PLC.

An alarm information module: the alarm information comprises two conditions of abnormal alarm and warning alarm, wherein the abnormal alarm refers to that serious faults occur to equipment, such as pressing of an equipment emergency stop button, incomplete detection of a tray, abnormal communication and the like, the processing level of the abnormal alarm is the highest level, the alarm mode is that the equipment stops a line, a buzzer rings, and an alarm indicator lamp flickers; the alarm is an abnormal condition that the equipment is abnormal but can be ignored temporarily and does not affect the operation of the equipment, for example, the value of an OCV (optical control circuit) collected signal is abnormal, the processing level of the alarm is low, the alarm mode is that the equipment is not disconnected, but a buzzer rings, and an alarm indicator lamp flickers. After the alarm occurs, the alarm can be manually processed in a mode that an alarm reset key is pressed, the alarm reset key can eliminate the sound of a buzzer, but an indicator lamp still flickers, and only after the fault causing the alarm is eliminated, the fault indicator lamp can be extinguished. All alarm information can be recorded into an abnormal record, and the alarm source is coded by adopting the relay number, so that the alarm can be conveniently searched and traced afterwards.

The information interaction module: the information interaction module completes the transmission of data and signals between the PLC and other equipment, including the communication with the OCV testing equipment, and mainly interacts with the testing starting and testing completion signals; interaction with a PLC (programmable logic controller), mainly a logistics line PLC, is mainly used for interaction of logistics information of the tray; interaction with a PC (personal computer) of a computer is mainly carried out, and interaction of tray bar code information, an OCV (open control circuit) test starting signal and an OCV test finishing signal is mainly carried out; and interaction with various types of sensors.

Common treatment: the common processing has the main effect of module cooperation, so that equipment with the same function can act simultaneously, reset and start simultaneously, and system debugging and resetting are facilitated.

OCV operation: the OCV operating module is the main module of the system, in which most of the functions of the system are implemented. The OCV operation module is divided into five submodules of manual operation, origin return, automatic operation, an output loop and picture output. The manual operation sub-module mainly completes the functions of executing corresponding operations according to manual commands, including operation preparation, returning to the original point, switching automatic modes, operation, resetting and the like. The origin return submodule executes origin return functions of each action component, including needle plate reset, roller reset, carrying-in and carrying-out reset and the like. The automatic operation submodule is a core module of the OCV operation module and mainly executes an OCV test function, the operation flow is shown in figure 2, when the PLC receives a tray detaching and feeding request, the PLC sends a tray detaching action signal to control a material flow line to detach a tray, then a material flow line carrying motor, a feeding roller and an OCV feeding mechanical arm simultaneously act to complete tray feeding, the tray enters an OCV station, a bar code gun obtains bar code information of a battery tray, after the PLC interacts a tray in-place signal with an upper computer PC and the bar code information of the battery tray, the PLC controls the tray to lift an air cylinder to act and detect an air cylinder in-place sensor to confirm that a detection needle bed is connected with the battery completely, the upper computer PC sends a needle bed connection success signal, the upper computer PC controls a detection instrument to start detecting and collect data, after the detection is completed, the upper computer PC sends a detection completion signal to the PLC, and after the, battery and needle bed disconnection, commodity circulation line transport motor, ejection of compact cylinder and OCV ejection of compact manipulator simultaneous movement accomplish the tray ejection of compact, and PLC sends and folds a set actuating signal, and control commodity circulation line folds a set action, and PLC sends the ejection of compact request, and OCV detects the completion.

The output loop module mainly completes all output actions needing to output variables in the running process of the PLC program, and mainly outputs all external points, such as various control points, external alarms and the like.

The picture output module is mainly used for finishing information interaction with the touch screen and outputting a display picture of the touch screen according to the man-machine interaction condition.

As shown in fig. 3, the operation flow of the PLC program is to accurately activate corresponding functions in the four modules according to different functional requirements, so as to complete the operation of the device. The following description will be made with the system power on as a time starting point.

The PLC is firstly electrified after the system power is turned on, the control program continues to perform the operation according to the state information of the last power-off time stored by the power-off protection unit, then a running preparation button needs to be manually pressed to start a running preparation function, specifically, the running preparation function is realized by keeping the functional modules which are being executed as original states, resetting the rest of the modules and the functions, then a return-to-original-point button needs to be manually pressed to confirm that the rest of the functions and the modules return to the original points except the current running function, then an automatic mode switching button continues to be pressed to start an automatic mode, and finally the running button is pressed to start the system and enter the automatic running mode.

In an automatic mode, the system enters a first cycle, if the photoelectric sensor detects that the battery tray reaches a specified position, the bar code gun acquires the bar code information of the battery, and simultaneously stores the bar code information into PLC addresses W6110-W6130 and sends the bar code information to an upper computer PC; judging whether the tray is an empty tray or a normal tray by the upper computer PC, and carrying the tray if the tray is the empty tray; if the tray is a normal tray, entering the next process; the testing cylinder acts to start testing the battery, meanwhile, the upper computer PC communicates with the tester through a serial port to acquire battery parameter information, and the measured data is stored in a database; then, whether the measurement result is correct or not is judged, and if the measurement result is incorrect, the measurement is returned again for re-measurement; until the data is judged to enter the next flow correctly; and after the test is finished, the automatic operation sub-module continues to execute the corresponding action.

Claims

1. Monomer power battery on-line measuring system, its characterized in that includes: the device comprises an upper computer PC, a PLC connected with the upper computer PC, a photoelectric sensor, a jacking cylinder, a blocking cylinder, a transfer sliding table cylinder, a power roller motor, a touch screen, a code scanning gun, an internal resistance tester (12) and an open-circuit voltage tester (13), wherein the photoelectric sensor, the jacking cylinder, the blocking cylinder, the transfer sliding table cylinder, the power roller motor, the touch screen and the code scanning gun are connected with the PLC independently; the upper computer provides abundant display for field operators of the battery production line and also completes analysis processing on data acquired by the tester; and the PLC executes the tasks distributed from the upper computer PC after receiving the command from the upper computer PC.