CN209895466U

CN209895466U - Lithium ion battery fire early warning device based on single chip microcomputer

Info

Publication number: CN209895466U
Application number: CN201920451164.4U
Authority: CN
Inventors: 王青松; 刘同宇; 刘昱君; 段强领; 孙金华
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2019-04-04
Filing date: 2019-04-04
Publication date: 2020-01-03
Anticipated expiration: 2029-04-04

Abstract

The utility model discloses a lithium ion battery conflagration early warning device based on singlechip mainly comprises fire signal monitored control system and communication early warning system. The fire signal monitoring system mainly comprises an infrared temperature sensor, a carbon monoxide gas sensor, a smoke gas sensor and the like. The communication early warning system mainly comprises an Arduino single-chip microcomputer circuit board, a Liquid Crystal Display (LCD), an early warning buzzer, an early warning indicator lamp and the like. The fire signal monitoring system monitors the working state of the target lithium ion battery in real time, transmits the signal to the single chip microcomputer control center, and the single chip microcomputer obtains the actual working state of the target lithium ion battery after making corresponding judgment and decides whether to send out an early warning acousto-optic signal and take follow-up fire-fighting linkage measures. The fire signal monitoring system and the communication early warning system are matched with each other and work cooperatively, so that dangerous situations can be found in the early stage of thermal runaway of the lithium ion battery, and countermeasures can be taken.

Description

Lithium ion battery fire early warning device based on single chip microcomputer

Technical Field

The utility model relates to a technical field of lithium ion battery's monitoring early warning, concretely relates to lithium ion battery conflagration early warning device based on singlechip, but it is real-time supervision target lithium ion battery operating condition and the conflagration early warning device who sends out reputation early warning signal before taking place the thermal runaway.

Background

With the increasing market demand of our country for new clean energy, lithium ion batteries have been vigorously developed due to the advantages of high specific energy storage, high cycle ratio, environmental friendliness, wide application range and the like. Particularly in recent years, China vigorously promotes the popularization of new energy automobiles from the political level, the output and sales volume of the new energy automobiles is explosively increased, and the market presents an obvious policy trend. However, some technical problems of the lithium ion battery itself still remain to be solved, and the thermal safety of the lithium ion battery is one of the most important problems. The lithium ion battery can reach the temperature for melting an aluminum current collector due to thermal runaway under the external condition of thermal abuse, so that the battery releases a large amount of smoke, and the battery is ignited and exploded. Therefore, the safety problem of lithium ion batteries is a bottleneck in their large-scale application.

The utility model discloses aim at designing one kind and use lithium ion battery as the safety precaution device of applied object, can take place the tertiary reputation early warning signal at target lithium ion battery before the thermal runaway, remind relevant personnel battery dangerous sign to guarantee that sufficient reaction time takes emergency measures. Because lithium ion battery can accompany obvious intensification process before taking place the thermal runaway on battery surface, until reaching a higher temperature, take place the thermal runaway, accompany smog and the gaseous release of characteristic simultaneously, so the utility model discloses chooseed for use battery surface temperature, smog concentration and carbon monoxide gas concentration as measuring signal, set for corresponding threshold value and reported to the police and judge, realized at the early target of finding the problem and sending tertiary reputation early warning signal of lithium ion battery thermal runaway, increased lithium ion battery system's whole security.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a novel conflagration early warning device to lithium ion battery specially improves lithium ion battery's safety in utilization. The utility model discloses the problem that solves is: a lithium ion battery fire signal monitoring device is designed, so that a corresponding abnormal signal can be detected before a target lithium ion battery is out of control due to heat, and an acousto-optic early warning signal is sent out to link subsequent fire-fighting measures. Therefore, the occurrence and propagation of thermal runaway of the lithium ion battery are coped with, and the overall safety performance of the system taking the lithium ion battery as a power source is effectively improved.

In order to solve the above problems and achieve the above object, the technical solution of the present invention is: a lithium ion battery fire early warning device based on a single chip microcomputer mainly comprises a fire signal monitoring system and a communication early warning system. The fire signal monitoring system mainly comprises an infrared temperature sensor, a smoke gas sensor, a carbon monoxide characteristic gas sensor, a communication line and the like; the communication early warning system mainly comprises an Arduino single-chip microcomputer circuit board, an early warning Light Emitting Diode (LED) lamp, a buzzer, a Liquid Crystal Display (LCD), a communication line and the like.

The fire signal monitoring system is arranged near a target lithium ion battery and can acquire working state signals of the battery in real time.

Furthermore, the infrared temperature sensor is a non-contact infrared temperature measuring sensor, an infrared sensing thermopile detector chip and a signal processing special integrated chip are simultaneously integrated and installed in the metal sealing cylinder, and a low noise amplifier, a 17-bit analog-to-digital converter and a digital signal processing unit are simultaneously integrated. The sensor can measure the surface temperature of an object at minus 70-380 ℃ for a long time, the corresponding detection temperature resolution is 0.02 ℃, the temperature measurement precision is 0.5 ℃, and the temperature of the sensor in a working environment is minus 40-125 ℃. The required power is directly provided by the Arduino singlechip circuit board.

Furthermore, the smoke gas sensor is selected, the monitoring concentration range is 50-10000 ppm, and the working environment is normal temperature and normal humidity. The required power is directly provided by the Arduino singlechip circuit board.

Further, a carbon monoxide combustible gas sensor is selected as the carbon monoxide characteristic gas sensor, the concentration range of the monitored CO is 10-1000 ppm, and the working environment is normal temperature and normal humidity. The required power is directly provided by the Arduino singlechip circuit board.

The communication early warning system mainly comprises an Arduino single-chip microcomputer circuit board serving as a control center, a Liquid Crystal Display (LCD), a Light Emitting Diode (LED) colored lamp for emitting a three-level acousto-optic early warning signal and a buzzer.

Furthermore, the Arduino single chip microcomputer is an open-source electronic prototype platform, and the device uses the unor3 to develop a learning control board. The program code is written in the Arduino IDE and uploaded to the Arduino board to realize the desired functions. The power supply of the Arduino single chip microcomputer can be matched with a special battery box and also can be directly connected with common power supplies such as a household circuit.

Further, a Light Emitting Diode (LED) colored lamp and a buzzer can send out three-level acousto-optic early warning signals, and the specific modes are as follows: the primary alarm signal is that the blue LED warning lamp is continuously turned on, related personnel are prompted that the surface temperature of the detected lithium ion battery is abnormally increased, and dangerous conditions are likely to occur when the temperature is continuously increased; the secondary alarm signal is that the blue LED warning lamp is turned off, the red LED warning lamp is turned on and begins to flash, and meanwhile, the buzzer sends out discontinuous alarm buzzing sound to prompt relevant personnel that the interior of the lithium ion battery exceeds the designed use temperature, so that the secondary alarm signal has great insecurity and measures are taken to cool down immediately; the three-level early warning signal is that the buzzer sends out continuous alarm buzzing sound, and the red LED warning light begins to continuously light, and the suggestion relevant personnel are detected inside the lithium ion battery and have begun to react, release many characteristic gases, if do not take corresponding measures, the lithium ion battery has very big possibility to take place thermal runaway, leads to dangerous situations such as follow-up conflagration explosion.

Further, Liquid Crystal Display (LCD) chooses for use 16 x 2 model, can show 16 characters in two lines, and every character 5 pixels are wide, 8 pixels are high, by the built-in chip drive of HD44780, have 16 available pins, and required power is directly provided by Arduino singlechip circuit board.

The utility model has the advantages that: 1. the fire early warning device is specially designed and manufactured aiming at the fire early warning requirement of the lithium ion battery, and the corresponding early warning parameters are set based on the actual research result of the lithium ion battery, so that the fire early warning device is more targeted to use. 2. The infrared temperature measurement is a non-contact temperature measurement mode, so that the damage of the sensor caused by the high surface temperature when the lithium ion battery is out of control due to heat is effectively avoided. 3. The temperature signal and the characteristic gas concentration signal cooperate to carry out early warning judgment, so that the early warning precision is improved, and the dangerous case can be found at the early stage of the thermal runaway of the lithium ion battery, and measures can be taken. 4. The volume is small, the arrangement is flexible, and the method can be applied to diversified actual engineering environments.

Drawings

Fig. 1 is a circuit diagram of a lithium ion battery fire early warning device based on a single chip microcomputer of the utility model;

FIG. 2 is a diagram of a lithium ion battery fire early warning device based on a single chip microcomputer;

fig. 3 is a diagram of an embodiment of a lithium ion battery fire early warning device based on a single chip microcomputer of the present invention;

fig. 4 is an early warning result diagram of an implementation case of the lithium ion battery fire early warning device based on the single chip microcomputer of the utility model;

fig. 5 is a flow chart of the lithium ion battery fire early warning device.

Detailed Description

The present invention will be further described with reference to the accompanying drawings, embodiments and experimental verification cases.

The utility model relates to a lithium ion battery conflagration early warning device based on singlechip mainly includes: fire signal monitoring system and communication early warning system.

Three sensors of the fire signal monitoring system are installed near the target lithium ion battery. The infrared temperature sensor measures temperature in a non-contact mode, is arranged on the surface, facing a target lithium ion battery, of the lithium ion battery, and is 3-5 cm away from the target lithium ion battery; the smoke gas sensor and the carbon monoxide characteristic gas sensor are arranged in the upper space of the target lithium ion battery. When the lithium ion battery is out of control due to heat, the surface of the lithium ion battery is often heated rapidly, and a large amount of high-temperature smoke is released, so that the arrangement position of the sensor is kept at a proper distance from the target lithium ion battery, and the proper working environment of the sensor is ensured.

The communication early warning system mainly comprises an Arduino single-chip microcomputer circuit board, an LCD (liquid crystal display) screen, an LED colored lamp for sending out an early warning signal and a buzzer. Wherein LED color lamp, bee calling organ and LCD liquid crystal display weld on same circuit board, arrange the position of comparatively keeping away from target lithium ion battery with Arduino singlechip together. And real-time monitoring signals of the fire signal monitoring system are transmitted to the singlechip through a communication line to carry out threshold judgment. Taking 18650 type lithium ion battery as an example, the three-level temperature threshold is set to 60 ℃, 80 ℃ and 90 ℃, and the early warning threshold can be adjusted according to actual requirements under other engineering application conditions. The smoke and carbon monoxide gas concentration thresholds were set at 300ppm, i.e., any change in gas concentration from the atmospheric environment was considered an abnormal condition. As shown in fig. 1, a logic flow chart of the early warning device sending the early warning signal is shown, and the internal code of the single chip microcomputer is written according to the logic flow chart.

Fig. 2 shows a specific circuit diagram of the warning device, and the connection of the corresponding circuits is welded according to the diagram. The power source of the early warning device can adopt a special battery box, and can also be obtained through a household circuit, an automobile power supply and other modes.

Fig. 3 shows a simplified object diagram of the device, which is small in size and convenient to use, and the sensor probe can be freely installed at a proper position.

In order to verify the practical function of the early warning device, a 18650 type ternary lithium ion battery is used as an early warning monitoring target to carry out 4 times of verification experiments, the experimental arrangement is shown in fig. 4, and the specific experimental data is shown in table 1.

TABLE 1 summary of the early warning time points and the experimental phenomenon time points of the battery characteristics

Analyzing the experimental data, the following conclusions can be basically obtained: the utility model discloses before lithium ion battery takes place the thermal runaway, can in time send acousto-optic early warning signal, guarantee the early warning reaction time about 5 minutes basically, be favorable to developing of fire control measures such as follow-up putting out a fire. This group's verifiability experiment has examined the utility model discloses have early warning lithium ion battery thermal runaway's function in advance really, objectively up-regulated the security performance in the lithium ion battery use, concrete early warning result is seen in figure 5. The present embodiment is only an exemplary illustration of the present invention, and does not limit the protection scope thereof, and some modifications and decorations made by those skilled in the art without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a lithium ion battery fire early warning device based on singlechip which characterized in that: mainly constitute by fire signal monitored control system and communication early warning system, wherein:

the fire signal monitoring system is mainly composed of an infrared temperature sensor, a smoke gas sensor, a carbon monoxide characteristic gas sensor and a communication line, and is used for measuring the state information of a target battery in real time by taking the surface temperature, smoke and characteristic gas concentration of the target battery as monitoring signals and transmitting the monitoring signals to a data processing center through the communication line for threshold judgment;

communication early warning system comprises Arduino singlechip circuit board, early warning emitting diode (LED) lamp, bee calling organ, Liquid Crystal Display (LCD) and communication line, and Arduino singlechip circuit board chooses for use Arduino Uno type circuit board, can compile corresponding program code in Arduino IDE environment, and acousto-optic warning signal can be sent out when taking place the dangerous situation to early warning emitting diode (LED) lamp and bee calling organ.

2. The lithium ion battery fire early warning device based on the single chip microcomputer of claim 1, wherein: the Arduino single-chip microcomputer circuit board is used as a data processing center and a control center, receives real-time monitoring signals of the sensors, judges unified threshold values, and can start Light Emitting Diode (LED) colored lamps and a buzzer to send out acousto-optic early warning signals when dangerous conditions are determined to occur.

3. The lithium ion battery fire early warning device based on the single chip microcomputer of claim 1, wherein: the early warning device is designed specially for the lithium ion battery and is flexible in arrangement, each sensor used by the early warning device can be freely arranged on the surface, above and nearby the target lithium ion battery, the early warning device can be flexibly arranged according to actual conditions, an infrared temperature measurement mode is adopted for solving the problem that the surface temperature rise is obvious when the lithium ion battery is out of control due to heat, carbon monoxide/hydrogen is selected as a characteristic gas to detect the working state of the lithium ion battery, corresponding threshold parameters can be set specifically for different batteries, and early warning signals can be sent 5 minutes before the lithium ion battery is out of control due to heat.

4. The lithium ion battery fire early warning device based on the single chip microcomputer of claim 1, wherein: the Liquid Crystal Display (LCD) can display the temperature measured by the infrared temperature sensor in real time and record the measured highest temperature value and the measured lowest temperature value, and the Liquid Crystal Display (LCD) adopts a 16X 2 type liquid crystal display.