Lithium-ion battery rapid temperature testing platform and rapid temperature detection method

Abstract

This invention relates to a rapid temperature testing platform for lithium batteries and a method for rapid temperature detection, belonging to the field of control. The rapid temperature testing platform for lithium batteries includes a testing circuit and a testing chamber. The testing circuit includes a power supply, an MCU control module, a temperature acquisition module, a touch screen, a current commutation module, and a temperature control module. The temperature acquisition module, touch screen, current commutation module, and heat dissipation circulation unit are directly connected to the MCU control module. The temperature control module is connected to the current commutation module. The testing chamber includes an upper housing space and a lower control box. The housing space is used to install the lithium battery pack to be tested. The temperature acquisition module is located in the housing space near the lithium battery pack to be tested. The touch screen and MCU control module are located on both sides of the control box, and the heat dissipation circulation unit is located in the middle. This invention enables rapid testing of the high and low temperature protection logic of lithium battery protection boards, while improving the accuracy of protection temperature testing.

Description

Technical Field

[0001] This invention relates to a rapid temperature testing platform for lithium batteries and a method for rapid temperature detection, belonging to the field of control. Background Technology

[0002] With technological advancements, lithium batteries are finding applications in a wider range of fields, such as power and energy storage.

[0003] Since lithium batteries are not recommended to be used in excessively high or low temperatures, they are usually equipped with a lithium battery protection board for protection. In order to ensure that the lithium battery protection board has played a protective role, it is necessary to test its high and low temperature protection logic before the lithium battery protection board is actually put into use. Because the test cabinet is large and the temperature changes slowly, a lot of time is spent testing the high and low temperature protection of the lithium battery protection board. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a rapid temperature testing platform system and method, enabling rapid testing of the high and low temperature protection logic of lithium battery protection boards while improving the accuracy of protection temperature testing.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] The present invention provides a rapid lithium battery temperature testing platform, comprising a testing circuit and a testing box. The testing circuit includes a power supply, an MCU control module, a temperature acquisition module, a touch screen, a current commutation module, and a temperature control module. The temperature acquisition module, the touch screen, the current commutation module, and the heat dissipation circulation unit are directly connected to the MCU control module. The temperature control module is connected to the current commutation module.

[0007] The test chamber includes an upper housing space and a lower control box. The housing space is used to install the lithium battery pack to be tested. The temperature acquisition module is located in the housing space near the lithium battery pack to be tested. Touch screens and MCU control modules are located on both sides of the control box. A heat dissipation circulation unit is located in the middle. The heat dissipation circulation unit includes cooling fans located at the top and / or bottom.

[0008] According to the lithium battery temperature rapid testing platform, the touch screen displays the collected temperature, target temperature, temperature data curve, and target temperature change of the temperature acquisition module in real time. The MCU control module controls the temperature control module to perform heating, cooling, or heat preservation operation signals through the current commutation module. The touch screen has a human-machine interface and receives data messages sent by the MCU control module. After parsing the data, the touch screen displays it on the screen.

[0009] According to the aforementioned rapid temperature testing platform system, the temperature acquisition module is used to detect the temperature inside the containment space and the temperature of the temperature control module. The containment space is used to place the testing module. The containment space is provided with an outlet interface and a ventilation port between it and the temperature control module. The temperature acquisition module acquires the temperature inside the containment space in real time.

[0010] According to the aforementioned rapid temperature testing platform system, the temperature acquisition module consists of a 10kΩ thermistor and a 10kΩ resistor connected in series. A 3.3V voltage is applied to the temperature acquisition module, and the MCU control module acquires the thermistor voltage, performs voltage conversion, resistance conversion, and temperature conversion to obtain the acquired temperature, and generates a message to be sent to the touch screen for display.

[0011] According to the aforementioned rapid temperature testing platform system, the heat dissipation circulation unit further includes a heat sink and a thermoelectric cooler. The heat sink and the cooling fan are located at opposite ends of the thermoelectric cooler. The thermoelectric cooler is a TEC1-12705. The thermoelectric cooler is connected to an MCU control module via a current commutation module. The MCU control module controls the operating status of the temperature control module.

[0012] According to the aforementioned rapid temperature testing platform system, the current reversing module includes two sets of relays. The MCU control module controls the working state of the thermoelectric cooler by closing the relay pins, and controls the current direction to change the heating or cooling direction of the thermoelectric cooler. The cooling fan is controlled to start and stop by the relays.

[0013] According to the aforementioned rapid temperature testing platform system, the target temperature can be modified by operating the temperature setting area on the touch screen: Clicking the temperature setting position on the main interface of the touch screen will jump to the temperature setting interface. Enter the target temperature in the corresponding input box, and clicking the setting button will automatically generate a message and send it to the MCU control module. After the MCU control module parses the data, it changes the target temperature. After returning to the main interface, the touch screen will display the current target temperature.

[0014] According to the aforementioned rapid temperature testing platform system, the temperature curve display function of the containment space can display the temperature change curve of the containment space through a touch screen. Clicking the temperature display area of ​​the touch screen will enter the temperature curve interface. The touch screen receives temperature curve data at fixed intervals, and displays the curve after parsing the received data.

[0015] The present invention discloses a method for rapid temperature detection using a lithium battery rapid temperature testing platform, comprising the following steps.

[0016] 1) The touchscreen features human-computer interaction with hotkeys in different areas. Messages are sent to the MCU control module via buttons, and the system's operating status is controlled by the touch control buttons. Clicking the temperature setting position on the main touchscreen interface will take you to the temperature setting interface. Enter the target temperature in the corresponding input box, and clicking the set button will automatically generate a message sent to the MCU control module. After parsing the data, the target temperature is changed. After returning to the main interface, the touchscreen will automatically update the current target temperature. At the same time, the MCU control module sends data messages to the touchscreen. After parsing the data, the touchscreen displays the current temperature of the storage space, the set temperature, and the temperature curve.

[0017] 2) Temperature data acquisition and processing: Collect the thermistor voltage data, generate temperature data through voltage conversion, resistance conversion, and temperature conversion, and send it to the touch screen for display.

[0018] This invention enables rapid testing of high and low temperature protection logic for lithium battery protection boards, while improving the accuracy of protection temperature testing.

[0019] In this invention, the touch screen can display the temperature collected by the temperature acquisition module, the target temperature, the temperature data curve, and the target temperature change in real time. The MCU control module controls the temperature control module to perform heating, cooling, or temperature maintenance through the current commutation module. Attached Figure Description

[0020] Figure 1 Diagram showing the connection relationship between the rapid temperature testing platform system and methods;

[0021] Figure 2 A flowchart illustrating the control steps of a rapid temperature testing platform system and method;

[0022] Figure 3 Block diagram of the rapid temperature testing platform system and method. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0024] The present invention is as follows Figure 1 The hardware structure includes test circuitry and a test box.

[0025] Test circuit such as Figure 1 As shown, it includes a power supply, an MCU control module, a temperature acquisition module, a touch screen, a current commutation module, and a temperature control module. The temperature acquisition module, the touch screen, the current commutation module, and the heat dissipation circulation unit are directly connected to the MCU control module, and the temperature control module is connected to the current commutation module.

[0026] Test box such as Figure 3 As shown, the device includes an upper housing space and a lower control box. The housing space is used to install the lithium battery pack under test. The temperature acquisition module is located in the housing space near the lithium battery pack under test. Touch screens and MCU control modules are located on both sides of the control box. A heat dissipation circulation unit is located in the middle. The heat dissipation circulation unit includes cooling fans located at the top and / or bottom.

[0027] The test circuit in this invention is powered by 12V and has a built-in 12V to 5V converter to power the various modules of the system. The temperature acquisition module detects the temperature within the containment space and the temperature of the temperature control module. The temperature acquisition module, touchscreen, temperature control module, and MCU control module are connected. The touchscreen displays the acquired temperature, target temperature, temperature data curve, and target temperature adjustment in real time. The MCU control module controls the operation of the temperature control module based on the acquired temperature.

[0028] The temperature acquisition module consists of a 10kΩ thermistor and a 10kΩ resistor connected in series. After applying a 3.3V voltage, the MCU control module acquires the thermistor voltage, performs voltage conversion, resistance conversion, and temperature conversion to obtain the acquired temperature, and generates a message to be sent to the touch screen for display.

[0029] The touchscreen features human-machine interaction, with hotkeys in different areas. It sends messages to the MCU control module via UART, and the touch control buttons control the system's operating status. Clicking the temperature setting area on the main touchscreen interface redirects to the temperature setting screen. Entering the target temperature in the corresponding input box and clicking the set button automatically generates a message sent to the MCU control module. After parsing the data, the MCU changes the target temperature. Returning to the main interface, the touchscreen automatically updates the current target temperature. Simultaneously, the MCU control module sends data messages to the touchscreen, which parses the data and displays the current and set temperatures, as well as a temperature curve.

[0030] The temperature control module includes a thermoelectric cooler and a heat sink. The thermoelectric cooler is a TEC1-12705, and the heat sink is an aluminum heat sink. The current reversing module includes two sets of relays; the MCU control module controls the operating state of the thermoelectric cooler by closing the relay pins, controlling the current direction to change the heating or cooling direction of the thermoelectric cooler. The circulating fan and the cooling fan are controlled to start and stop via relays.

[0031] The method for rapid temperature testing using the rapid temperature testing platform system of the present invention, such as... Figure 2 As shown, it includes the following steps:

[0032] Step 1) Initialize system hardware, initialize system clock, configure interrupt response, configure ADC parameters, configure UART parameters, and configure LED indicators.

[0033] Specifically, initialize the system hardware, configure the main control IC (STM32F103ZE) to operate at 72MHz, and configure the interrupt priority to level 2. Configure ADC parameters, enable the clock of the ADC sampling port pin, enable the ADC pin, enable the DMA pin, enable the temperature acquisition pin to analog mode, configure the ADC DMA to cyclic mode, enable multi-channel, continuous conversion mode, set the ADC sampling channel and sampling time, and enable the ADC sampling function after calibrating the ADC. Configure UART parameters, enable the GPIO port and UART port clock, specify the interrupt priority, interrupt channel and priority, configure the GPIO multiplexed push-pull output and analog output of the UART pin, configure the baud rate, word length, stop bits, parity bits, hardware control flow, and transmit / receive mode of the UART port, then enable idle interrupt and receive interrupt, and then enable the serial port. Configure LED indicators, enable the clock of the LED pin, enable the GPIO port, set the specific pin of the GPIO port, set the output mode to push-pull output mode, and the transmission rate to 50MHz.

[0034] Step 2) Initialize the system software and configure global variables.

[0035] Specifically, the global variables are configured as follows: housing temperature, cooling fan temperature, set temperature, thermistor parameters, startup flag, and temperature flag.

[0036] Step 3) Temperature data acquisition and processing: Collect the thermistor voltage data, generate temperature data through voltage conversion, resistance conversion, and temperature conversion, and send it to the touch screen for display.

[0037] Specifically, temperature data acquisition uses voltage sampling every 10ms. The thermistor temperature calculation formula is: Rt = R * EXP(B * (1 / T1 - 1 / T2)), where T1 and T2 refer to Kelvin temperatures. Rt is the resistance of the thermistor at temperature T1. R is the nominal resistance of the thermistor at room temperature T2. A 100K thermistor has a resistance of 10K at 25℃ (i.e., R = 10K). T2 = (273.15 + 25), EXP is e to the power of n, and B is an important parameter of the thermistor. Through conversion, the relationship between temperature T1 and resistance Rt can be obtained: T1 = 1 / (ln(Rt / R) / B + 1 / T2). The corresponding Celsius temperature is t = T1 - 273.15, with a +0.5 error correction. The B value of a 10K thermistor is 3450.

[0038] The temperature acquisition formula is: for(i=0;i<2;i++)

[0039] {

[0040] volta[i]=(float)AD_Value[i] / 4095*3.3;

[0041] Rt[i]=(100000*volta[i]) / (3.3-volta[i]);

[0042] temp[i]=(1 / (log(Rt[i] / Rp) / Bx+(1 / T2)))-273.15+0.5;

[0043] }

[0044] The screen data format is t1.txt="%d" (temperature data of the storage space), t2.txt="%d" (temperature data of the cooling fan), n10.val=%d (temperature control data),) add 1,1, Temperature curve of the storage space is generated.

[0045] Step 4), communication protocol processing: The MCU control module changes the system operating status based on the touchscreen message data. The communication format is: UART, baud rate 9600bps, 1 stop bit, 8 data bits, and no parity.

[0046] Specifically, the protocol format is as follows:

[0047] beginning Function code data Finish 0xcb 0x01 0x01 (1 for on, 0 for off) 0xff

[0048] Protocol Directory:

[0049] (1) Function code 0x01, control system working status

[0050] (2) Function code 0x02, change the control temperature

[0051] The specific communication protocol message is as follows:

[0052] (1) Function code 0x01 controls the system's operating status.

[0053]

[0054] (2) Function code 0x02, change the control temperature.

[0055]

[0056] Step 5), temperature control function: when reading the protocol parsing requires the system to start working, the temperature control module is controlled to work according to the temperature data.

[0057] Specifically, when the detection function code is 0x01 and the data is 0x01, the system starts working, the heat conduction fan turns on, and the cooling fan starts according to the cooling fan temperature control. The cooling fan turns on when the cooling fan temperature is above 30℃ or below 0℃. When the control temperature is greater than the measured temperature, the temperature flag is set to 0, the heating function is activated, and the heating function stops when the measured temperature reaches the control temperature +1. When the measured temperature reaches the control temperature -1, the heating function is activated, and the temperature flag is set to 1. When the control temperature is less than the measured temperature, the cooling function is activated, and the cooling function stops when the measured temperature reaches the control temperature -1. When the measured temperature reaches the control temperature +1, the cooling function is activated. When the temperature flag is 1, the LED flashes every 1 second, and the buzzer sounds 3 times. When the temperature flag is 0, the LED remains constant, and the buzzer does not sound. When the detection function code is 0x01 and the data is 0x00, the system stops working, no longer cooling or heating, and only collects temperature data.

Claims

1. A lithium battery temperature rapid test platform, comprising a test circuit and a test box, characterized in that: the test box adopts an upper and lower split structure, the upper part is a containing space for installing the lithium battery group to be tested, and the lower part is a control box; the test circuit comprises a power supply, an MCU control module, a temperature acquisition module, a touch screen, a current reversing module and a temperature control module; the temperature acquisition module, the touch screen and the current reversing module are electrically connected with the MCU control module, and the temperature control module is connected with the current reversing module; the temperature acquisition module is arranged in the containing space and is used for collecting the temperature of the containing space; the touch screen and the MCU control module are arranged on the two sides of the control box respectively; the temperature control module comprises a single semiconductor refrigerating fin; the current reversing module comprises two groups of relays; the MCU control module changes the current direction flowing through the semiconductor refrigerating fin by controlling the pin closing mode of the two groups of relays, so that the semiconductor refrigerating fin is switched between the refrigeration mode and the heating mode; a heat dissipation circulation unit is centrally arranged in the middle of the control box, the heat dissipation circulation unit comprises a heat dissipation fan, is used for forcibly exchanging the heat or cold produced by the semiconductor refrigerating fin, and forms an air flow circulation with the containing space through a ventilation opening; the temperature acquisition module is composed of a 10kΩ thermistor and a 10kΩ resistor in series, and a 3.3V voltage is applied to the series circuit; the MCU control module is used for collecting the voltage across the thermistor, and the collected temperature is obtained through the algorithms of voltage conversion, resistance conversion and temperature conversion, and a data packet containing the collected temperature is generated and sent to the touch screen; the touch screen is used for displaying the collected temperature, the preset target temperature and the temperature change curve in real time; the touch screen is also provided with a preset man-machine interface, the interface comprises a temperature setting hot key; in response to the clicking operation of the user on the temperature setting hot key, the touch screen jumps to the temperature setting interface, receives the target temperature value input by the user, and automatically generates a corresponding setting packet and sends it to the MCU control module; the MCU control module analyzes the setting packet to update the target temperature, and controls the temperature control module to work, so that the temperature of the containing space tends to the updated target temperature.

2. The rapid lithium battery temperature test platform of claim 1, wherein, The touch screen also displays the working state signal of the temperature control module controlled by the MCU control module through the current reversing module in real time.

3. The rapid lithium battery temperature test platform of claim 1, wherein, The containing space is internally provided with an outgoing interface for connecting the lithium battery group to be tested.

4. The rapid lithium battery temperature test platform of claim 1, wherein, The heat dissipation circulation unit further comprises a heat sink attached to both ends of the semiconductor refrigerating fin, and the semiconductor refrigerating fin adopts a TEC1-12705 model.

5. The rapid lithium battery temperature test platform of claim 1, wherein, The touch screen receives temperature data from the MCU control module at fixed time intervals and dynamically updates and displays in curve form in the man-machine interface.

6. The rapid lithium battery temperature test platform of any one of claims 1 to 5, wherein, The heat dissipation fan is at least two, which are arranged above and / or below the heat dissipation circulation unit in the control box.

7. A temperature rapid detection method using the lithium battery temperature rapid test platform according to any one of claims 1 to 6, characterized in that, comprising the following steps: Target temperature setting through human-computer interaction interface of the touch screen: click temperature setting hot key of main interface, jump to temperature setting interface, input target temperature value, trigger the touch screen to automatically generate and send setting message to the MCU control module; The MCU control module analyzes the setting message, updates internal target temperature value, and controls working mode and power of the single semiconductor refrigeration piece through the current commutation module according to the updated target temperature value; Real-time collection of space temperature through the temperature collection module: the MCU control module collects voltage between two ends of the 10kΩ thermistor, executes voltage conversion, resistance conversion and temperature conversion algorithm, and obtains real-time collection temperature; Data feedback and display: the MCU control module encapsulates the real-time collection temperature into data message and sends to the touch screen; the touch screen analyzes the data message and updates and displays the collection temperature, the target temperature and the curve of the collection temperature changing with time on the main interface in real time.

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