New energy automobile battery accident energy dissipation control protection method and system

Abstract

The invention discloses a new energy automobile battery accident energy dissipation control protection method and system, and the method comprises the steps: adding an insulating fireproof isolation material between two adjacent battery units, connecting a high-speed fuse on a loop of each battery unit in series, and connecting energy dissipation branches at two ends of each battery unit in parallel; the controller monitors the state of the fast-acting fuse of each battery unit; when a short-circuit fault occurs, the fast-acting fuse is fused and sends a fault signal to the controller; and the controller drives the energy dissipation branch connected with the fault battery unit in parallel to be conducted. The system provided by the invention comprises a battery pack, wherein an insulating fireproof isolation material is arranged between adjacent battery units (4); a high-speed fuse (2) is connected in series on a loop of each battery unit (4), and an auxiliary contact of each high-speed fuse (2) is in communication connection with the controller (1); and two ends of each battery unit (4) are connected in parallel with an energy dissipation branch formed by connecting a silicon controlled rectifier (3) and a linear resistor (5) in series.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium battery accident protection control, and in particular to a new energy vehicle battery accident energy dissipation control protection method and system. BACKGROUND

[0002] With the popularity of new energy vehicles, the safety of the power battery system has become the focus of the industry and society. The battery pack is prone to thermal runaway under extreme conditions such as overcharging, internal short circuit or severe impact, leading to fire, explosion and other serious accidents. Therefore, an efficient and reliable battery accident energy dissipation control protection system is urgently needed, and its core function is to quickly cut off the fault path when the battery has an initial fault, and quickly and safely release the residual energy stored in the faulty battery cell, fundamentally curb the thermal runaway chain reaction, gain valuable time for passengers to escape, and maximize the safety of the vehicle and the passengers.

[0003] At present, the mainstream scheme of the BMS system of the new energy vehicle relies on a control device composed of some electronic components to realize a single power-off function. Although this kind of technical scheme can immediately cut off the connection between the battery pack and the external circuit when a short circuit occurs, realizing external fault power-off, it has a fundamental problem: the BMS system only solves the problem of external "power-off", but does not solve the problems of "internal isolation" and "energy dissipation". Specifically, after the BMS system acts to realize external power-off, the "faulty battery cell" with internal short circuit still stores a certain amount of energy, which will be continuously released at the internal short circuit point, generating a large amount of energy and causing thermal runaway and fire of the battery itself. In addition, the "normal battery cell" that has not failed will provide a large amount of energy to the "faulty battery cell" through the fixed positive and negative connection plates, eventually causing thermal runaway and fire of the entire battery pack.

[0004] In addition, the existing BMS system generally does not have a fire extinguishing and alarm device, and there is a serious shortage of slow response to fire control and inability of the passengers to discover the fire in time. In addition, the current BMS system of the new energy vehicle immediately cuts off the external circuit and high-voltage power supply when the battery pack has a short circuit fault, which may cause abnormal accidents such as vehicle out of control and doors and windows cannot be opened, posing a great threat to the safety of vehicle driving and passenger escape. SUMMARY

[0005] In view of the above problems in the prior art, the present application aims to provide a new energy vehicle battery accident energy dissipation control protection method and system.

[0006] In order to achieve the above-mentioned purpose, the new energy vehicle battery accident energy dissipation control protection method provided by the present application adopts the following technical scheme: S1. Insulating fireproof isolation material is arranged between two adjacent battery units, a fast fuse with auxiliary contact is connected in series in the loop of each battery unit, and a dissipation branch is connected in parallel at both ends of each battery unit; S2. A controller is used to monitor the state of the fast fuse of each battery unit to determine whether a short circuit fault occurs in a battery unit; S3. When a short circuit fault occurs in a battery unit, the fast fuse connected to the battery unit is fused, the auxiliary contact of the fast fuse is actuated, and a fault signal is sent to the controller; S4. After the controller receives the fault signal, the dissipation branch connected in parallel with the battery unit where the fault occurs is immediately turned on to release the residual energy of the battery unit where the fault occurs.

[0007] The system provided by the application adopts the following technical scheme: It comprises a battery pack composed of a plurality of parallel battery units, insulating fireproof isolation material is arranged between each adjacent battery unit, a fast fuse is connected in series in the loop of each battery unit, the auxiliary contact of each fast fuse is in communication connection with a controller, the controller is powered by the battery pack, a dissipation branch is connected in parallel at both ends of each battery unit, each dissipation branch is composed of a thyristor and a linear resistor connected in series, and the output end of each thyristor is in communication connection with the controller.

[0008] In the above technical scheme, an alarm in communication connection with the controller is further included.

[0009] In the above technical scheme, an automatic fire extinguishing device is further included, the automatic fire extinguishing device is composed of a fire extinguisher, a direct current electromagnetic valve in communication with the fire extinguisher, and a nozzle near each battery unit and in communication with the corresponding direct current electromagnetic valve, and each direct current electromagnetic valve is in communication connection with the controller.

[0010] In the above technical scheme, the linear resistor is composed of a plurality of electric furnace filaments connected in parallel.

[0011] In the above technical scheme, a cooling fan is fixed near each linear resistor, and each cooling fan is in communication connection with the controller.

[0012] In the above technical scheme, the controller is a programmable logic controller.

[0013] Compared with the prior art, the application has the advantages that when internal short circuit occurs in any one battery unit, the corresponding connected fast fuse is fused immediately, on the one hand, the other normal parts of the system are electrically isolated in the physical layer, and the fault range is effectively prevented from further expanding. On the other hand, the controller triggers the exclusive energy dissipation branch of the fault battery unit according to the fast fuse state signal, and the residual energy in the fault battery unit is rapidly released by means of the linear resistor, so that the risk of heat runaway, fire or explosion caused by energy accumulation is fundamentally eliminated. In addition, the application integrates the exclusive protection module composed of the fast fuse, the thyristor and the linear resistor for each battery unit in the battery pack, and is equipped with an intelligent controller, so that the cooperative control from fault detection, electrical isolation to energy management can be realized. Through the above technical scheme, the application can protect the short circuit fault of the battery assembly such as the ternary lithium battery, the lithium iron phosphate battery, the semi-solid battery and the all-solid battery under various working conditions such as charging, running and collision, and has certain protection effect on personnel fire extinguishing safety and fire escape. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is the system circuit structure diagram provided by the application.

[0015] In the figure: controller 1, fast fuse 2, thyristor 3, battery unit 4, linear resistor 5. DETAILED DESCRIPTION

[0016] The new energy automobile battery accident energy dissipation control protection method provided by the application will be further described below in combination with the accompanying drawings and specific embodiments. Figure 1 The specific steps are as follows: S1. An insulating fireproof isolation material (not shown in the figure) is installed between two adjacent battery units 4, a fast fuse 2 with an auxiliary contact (not shown in the figure) is connected in series on the loop of each battery unit 4, the auxiliary contact of each fast fuse 2 is in communication connection with the controller 1, and an energy dissipation branch is connected in parallel at both ends of each battery unit 4; S2. The controller 1 monitors the state of the fast fuse 2 of the corresponding battery unit 4 through the auxiliary contact, and judges whether short circuit fault occurs in the battery unit 4; S3. When one or more battery units 4 have short circuit fault, the corresponding connected fast fuse 2 is fused, and the auxiliary contact of the fast fuse acts and sends a fault signal to the controller 1; S4. After the controller receives the fault signal, the energy dissipation branch in parallel with the faulty battery unit 4 is immediately driven to be conductive, releasing the residual energy in the faulty battery unit 4.

[0017] In this embodiment, the safety protection is realized through the synergistic effect of fault detection, electrical isolation and active energy dissipation. In step S1, the system continuously monitors the state of each fast fuse 2 through the controller 1, and when a short circuit occurs in the battery unit 4, the corresponding fast fuse 2 is blown due to overcurrent, thereby electrically isolating the faulty unit 4 from the battery system and preventing other normal battery units 4 from reverse power supply. The auxiliary contact of the fast fuse 2 acts, and a fault indication signal is generated, and the controller 1 can accurately control the energy dissipation branch in parallel with the faulty unit 4 to be conductive according to the signal, so as to guide the residual energy in the battery unit 4 to the linear resistor 5 for rapid consumption in the form of heat energy, thereby actively eliminating the risk of thermal runaway caused by energy accumulation at the fault point.

[0018] The new energy vehicle battery accident energy dissipation control protection system provided by the present application adopts the following structure: As shown in Figure 1 A battery pack composed of a plurality of parallel battery units 4.

[0019] An insulating fireproof isolation material (not shown in the figure) is installed between each adjacent battery unit 4; a fast fuse 2 is connected in series on the loop of each battery unit 4, and the auxiliary contact (not shown in the figure) of each fast fuse 2 is in communication connection with the controller 1, and the controller 1 is powered by the battery pack. Each battery unit 4 has an energy dissipation branch connected in parallel at both ends, and each energy dissipation branch is composed of a thyristor 3 and a linear resistor 5 connected in series, and the output end of each thyristor 3 is in communication connection with the controller 1.

[0020] In order to remind the passengers, the output end of the controller 1 is electrically connected with an alarm (not shown in the figure).

[0021] In order to prevent fire or control the spread of fire when a fault occurs, an automatic fire extinguishing device (not shown in the figure) is also installed. The automatic fire extinguishing device is composed of a fire extinguisher (not shown in the figure), a direct current electromagnetic valve (not shown in the figure) in communication with the fire extinguisher, and a spray head (not shown in the figure) located near each battery unit 4 and in corresponding communication with the direct current electromagnetic valve, and each direct current electromagnetic valve is in communication connection with the controller 1.

[0022] In the above technical solution, the linear resistor 5 is composed of a plurality of electric furnace filaments (not shown in the figure) connected in parallel.

[0023] In order to dissipate heat and cool down, a cooling fan (not shown in the figure) is fixed near each linear resistor 5, and each cooling fan is in communication connection with the controller 1.

[0024] In the technical solution, the controller 1 is a programmable logic controller.

[0025] In the embodiment, the system is constructed as a distributed protection architecture based on modular design, and each battery unit 4 is provided with an independent protection unit. The fast fuse 2 is used as a primary protection element for short-circuit overcurrent detection and electrical isolation, and the auxiliary contact thereof is used as a fault state sensor. The energy dissipation branch is used as an energy discharge channel and is not working under normal conditions due to the turn-off of the thyristor 3. The controller 1 monitors the state of all auxiliary contacts in real time.

[0026] When a short circuit occurs in a certain battery unit 4, the fast fuse 2 of the battery unit 4 is fused, and the state change of the auxiliary contact is captured by the controller 1. The controller 1 immediately sends a trigger signal to the thyristor 3 corresponding to the battery unit 4 to make the thyristor 3 conductive, thereby forming a closed loop composed of the faulty battery unit 4, the thyristor 3 and the linear resistor 5, and realizing rapid consumption of electrical energy.

[0027] The controller 1 uses a programmable logic controller (PLC) as the system control core. The PLC collects the auxiliary contact on-off signal of each fast fuse 2 through its digital input module, and outputs a driving signal to the control electrode of each thyristor 3 through its digital output module. The user can flexibly set and modify the control logic by programming the PLC. For example, the functions of fault diagnosis, delay control, communication with the upper system of the vehicle, etc. can be realized, which enhances the adaptability and scalability of the system.

[0028] In the embodiment, the controller 1 synchronously drives the alarm (such as an audible and visual alarm) to start when controlling the energy dissipation branch to conduct. The alarm signal is used to provide visual and auditory warnings to the vehicle passengers and external personnel, indicating that the battery system has triggered a protection action and prompting the existence of a safety risk, thereby assisting personnel to take evacuation or rescue measures.

[0029] In the embodiment, the controller 1 can set a delay of a predetermined time before starting the automatic fire extinguishing device when performing active energy dissipation, and implementing fire extinguishing on the target area. The linkage of electrical energy dissipation and chemical fire extinguishing aims to further suppress the fire and handle the open fire or high temperature risk that may be caused by the battery short circuit.

[0030] In the embodiment, the controller 1 synchronously supplies power to the cooling fan when triggering the thyristor 3 to conduct, so as to forcibly cool the linear resistor 5 in operation. This can effectively reduce the temperature of the resistor and prevent it from being damaged due to overheating, thereby ensuring the reliability and continuity of the energy dissipation process.

Claims

1. A method for controlling and protecting the energy dissipation of batteries in new energy vehicles during accidents, characterized in that... The steps are as follows: S1. Install insulating and fireproof isolation material between two adjacent battery cells, connect a fast-acting fuse with auxiliary contacts in series in the circuit of each battery cell, and connect an energy dissipation branch in parallel at both ends of each battery cell. S2. Use the controller to monitor the status of the fast-acting fuses in each battery cell to determine if any battery cell has a short-circuit fault; S3. When a short circuit fault occurs in a battery cell, the fast-acting fuse connected to it blows, and at the same time, the auxiliary contact of the fast-acting fuse activates and sends a fault signal to the controller. S4. After receiving the fault signal, the controller immediately drives the energy dissipation branch connected in parallel with the faulty battery cell to conduct, releasing the residual electrical energy of the faulty battery cell.

2. A system for implementing the method of claim 1, comprising a battery pack consisting of a plurality of parallel battery cells (4), characterized in that: Insulating and fireproof isolation materials are installed between each adjacent battery cell (4); Each battery cell (4) has a fast-acting fuse (2) connected in series in its circuit. The auxiliary contacts of each fast-acting fuse (2) are connected in communication with the controller (1). The controller (1) is powered by the battery pack. Each battery cell (4) has a parallel energy dissipation branch at both ends. Each energy dissipation branch is composed of a thyristor (3) and a linear resistor (5) connected in series. The output of each thyristor (3) is connected to the controller (1) in communication.

3. The system according to claim 2, characterized in that: It also includes an alarm that is connected in communication with the controller (1).

4. The system according to claim 2, characterized in that: It also includes an automatic fire extinguishing device, which consists of a fire extinguisher, a DC solenoid valve connected to the fire extinguisher, and a nozzle located near each battery unit (4) and connected to the corresponding DC solenoid valve. Each DC solenoid valve is connected to the controller (1) in communication.

5. The system according to claim 2, characterized in that: The linear resistor (5) is composed of multiple heating wires connected in parallel.

6. The system according to claim 5, characterized in that: Each linear resistor (5) is equipped with a cooling fan, and each cooling fan is connected to the controller (1) via communication.

7. The system according to any one of claims 2 to 6, characterized in that: The controller (1) is a programmable logic controller.

Images