A fire warning system for a lithium battery energy storage system

Abstract

The present invention discloses a fire warning system for a lithium battery energy storage system. The temperature information of the battery pack is monitored by installing a temperature sensor inside the battery pack, and the temperature information is then transmitted to a BMS controller. The temperature information in the BMS controller is transmitted to a signal processing system through a CAN bus. The signal processing system controls a fire injection valve to spray a fire-fighting agent according to a temperature value and a temperature change rate, thereby realizing fire prevention and extinguishing functions, avoiding the problem of delayed start-up of a traditional fire-fighting system when an open fire has occurred, and ensuring the power safety of the lithium battery energy storage system to the greatest extent. In addition, the BMS controller in the present invention adopts a three-layer hierarchical control structure, which can realize temperature monitoring of large-capacity multi-battery packs.

Description

Technical Field

[0001] The present invention relates to the field of fire protection system safety technology, and in particular to a fire protection early warning system for a lithium battery energy storage system. Background Art

[0002] With the increase in electricity demand, in order to meet the normal operation of power plant equipment, user equipment and power systems, the power system has set requirements for frequency control. The lithium battery energy storage system combines the two main characteristics of power density and energy density, which is very suitable for the frequency regulation of the power system. In recent years, more and more lithium battery energy storage systems have begun to provide support for the power system. Lithium battery energy storage is mainly used in power grids, communications, uninterruptible power supplies and other energy storage power stations. Lithium battery energy storage is generally operated in the form of containers, and currently mainly operates outdoors.

[0003] Lithium battery energy storage mainly includes the fire hazards of lithium batteries and electrical equipment. Lithium battery fires are mainly caused by the decomposition and combustion of electrolytes due to heat. It is a compound gas combustion fire and a chemical reaction between the materials inside the battery. The large amount of heat generated by the decomposition of the electrolyte causes the battery to lose control, resulting in the combustion of the electrolyte. In large-scale lithium battery energy storage projects, battery modules have the characteristics of high density and centralized distribution. Multiple battery modules are connected in series and parallel to form a large energy storage system. This increases the probability of lithium battery failure, and the circuit cannot be cut off between batteries, increasing the probability of fire. The energy storage system is also equipped with many electrical equipment, and high-voltage and high-current cables are connected inside. If the heat is high for a long time, it will cause oxidation and corrosion of some electrical components in the cabinet, making it unable to meet the resistance and insulation requirements of the original design. There is a greater risk for the entire energy storage system and the probability of fire will also increase.

[0004] At present, most of the fire fighting systems used in energy storage systems are external common emergency fire fighting systems, which are separated from the energy storage lithium battery, and the energy storage system and the fire fighting system are not connected. Such a fire fighting system is only a fire fighting device, which cannot detect the status of the lithium battery, cannot prevent in advance, and cannot meet the fire fighting requirements of the lithium battery energy storage system in terms of early warning function.

[0005] In order to solve the above technical problems, a fire warning system of a lithium battery energy storage system is urgently needed to solve the existing technical problems. Summary of the invention

[0006] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a fire warning system for a lithium battery energy storage system, which monitors the temperature information of the battery pack by installing a temperature sensor inside the battery pack, and then transmits the temperature information to the BMS controller. The temperature information in the BMS controller is transmitted to the signal processing system through the CAN bus, and the signal processing system controls the fire injection valve to realize the injection of fire-fighting agents, thereby realizing the prevention and extinguishing functions.

[0007] The present invention is achieved through the following technical solutions.

[0008] A fire warning system for a lithium battery energy storage system, the fire warning system for the lithium battery energy storage system comprising: a lithium battery PACK module, a BMS controller module arranged in the lithium battery PACK module to obtain battery cell temperature information, and a signal processing system for processing a temperature signal and outputting a control signal;

[0009] The BMS controller module includes a BMU unit, which is arranged in the battery compartment and is electrically connected to a temperature sensor close to the surface of a single cell and a primary voltage detection sensor arranged at the output end of the single cell to monitor the temperature and voltage of the single cell.

[0010] Furthermore, the BMS controller module also includes a BCU unit, which is arranged in an upper box inside the packaging shell, receives the temperature value and voltage value of the single battery cell detected by the BMU unit through the CAN bus, and detects the total voltage value of the battery pack composed of multiple single battery cells.

[0011] Furthermore, the BMS controller module also includes a BAU unit, which is arranged in the upper box inside the packaging shell; the BAU collects and summarizes the temperature value, voltage value of the single battery cell in the BCU unit and the total voltage value information of the entire battery pack through the CAN bus, and communicates with the signal processing system through the CAN bus or serial port communication or network port communication.

[0012] Furthermore, the lithium battery PACK module includes a battery pack consisting of a plurality of battery cells and a packaging shell arranged outside the battery pack, the packaging shell separates the battery pack from the outside, and at the same time, a plurality of horizontally arranged partitions are arranged inside the packaging shell, and a plurality of separated battery compartments are formed between the partitions, and two of the battery packs are arranged in one battery compartment.

[0013] Furthermore, the packaging shell is in the form of a container, and after the battery packs are connected in parallel in pairs, several groups of battery packs connected in parallel in pairs are connected in series to increase the capacity and high-voltage current output of the lithium battery energy storage system. A fire-fighting agent injection device is arranged in the packaging shell, and a fire-fighting agent injection device is arranged on the fire-fighting agent injection device.

[0014] Furthermore, the BMU unit includes: a first-level MCU, a first-level battery monitoring chip and a first-level CAN communication module; a temperature sensor is provided on the side wall of each single battery cell, and the temperature sensor is close to the outer surface of the battery cell; the first-level battery monitoring chip is electrically connected to the temperature sensor, the first-level voltage detection sensor and the first-level MCU at the same time, collects the temperature and voltage signals of the battery cell in real time, and transmits the collected temperature and voltage signals to the first-level MCU; the first-level MCU stores the temperature and voltage signals and transmits them to the BCU unit through the first-level CAN communication module.

[0015] Furthermore, the BCU unit includes: a secondary voltage detection sensor, a secondary MCU, a secondary battery monitoring chip and a secondary CAN communication module; the secondary voltage detection sensor is electrically connected to the output end of the battery pack; the secondary battery monitoring chip is electrically connected to the secondary voltage detection sensor and the secondary MCU, collects the voltage signal of the battery pack in real time, and transmits the collected voltage signal to the secondary MCU; the primary CAN communication module is electrically connected to the secondary MCU, and the primary MCU transmits the temperature and voltage signals of the single battery cell to the BCU unit through the primary CAN communication module; the secondary MCU is electrically connected to the secondary CAN communication module, and transmits the temperature and voltage signals to the BAU unit through the secondary CAN communication module.

[0016] Furthermore, the BAU unit includes: a three-level MCU and a three-level CAN communication module, and the three-level MCU transmits the signal of the BCU unit to the signal processing system through the two-level CAN communication module.

[0017] Furthermore, the temperature sensor is an NTC thermistor, the primary battery monitoring chip communicates with the primary MCU via a serial port communication method, and the secondary battery monitoring chip communicates with the secondary MCU via a serial port communication method.

[0018] Further, the signal processing system includes an acquisition module, a logic control module, and a display module; the acquisition module communicates with the three-level CAN communication module, outputs an indication signal, and receives data from the BAU unit;

[0019] Furthermore, the display module is connected to an external display device for displaying the voltage, temperature, temperature change rate of the battery cell, the total voltage of the battery pack, and the status of the fire spray solenoid valve.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention installs a temperature sensor inside the battery pack to monitor the temperature information of the battery pack, and then transmits the temperature information to the BMS controller. The temperature information in the BMS controller is transmitted to the signal processing system through the CAN bus. The signal processing system controls the fire spray valve to spray the fire agent according to the temperature value and the temperature change rate, thereby realizing the prevention and fire extinguishing functions, avoiding the problem of delayed start-up of the traditional fire protection system when an open fire has occurred, and ensuring the power safety of the lithium battery energy storage system to the greatest extent;

[0022] 2. The BMS controller in the present invention adopts a three-layer hierarchical control structure, which can realize temperature monitoring of large-capacity multi-battery packs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A diagram of a fire warning system of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of the lithium battery pack module of the present invention;

[0025] Figure 3 It is the composition diagram of BUM module;

[0026] Figure 4 This is a diagram of the signal processing system.

[0027] In the figure: 1. temperature sensor; 2. fire spray solenoid valve; 4. packaging shell; 5. battery pack; 6. box body. DETAILED DESCRIPTION

[0028] The following will clearly and completely describe the technical solutions of various embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] The present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0030] like Figures 1 to 4 As shown, a fire warning system of a lithium battery energy storage system includes: a lithium battery PACK module, a BMS controller module and a signal processing system.

[0031] The lithium battery PACK module includes a battery pack 5 composed of a plurality of battery cells and a packaging shell 4 arranged outside the battery pack 5; the packaging shell 4 separates the battery pack 5 from the outside;

[0032] At the same time, a plurality of horizontally arranged partitions are arranged inside the packaging shell 4, and a plurality of separated battery compartments are formed between the partitions. Two battery packs 5 are arranged in one battery compartment, and are placed in layers in this way;

[0033] The packaging shell 4 may be in the form of a container.

[0034] In order to increase the capacity of the lithium battery energy storage system, the battery packs 5 are connected in parallel in pairs;

[0035] In order to output high voltage current, a plurality of battery packs 5 connected in parallel are connected in series.

[0036] A BMS controller is arranged in the packaging shell 4 .

[0037] A fire-fighting agent spraying device is arranged in the packaging shell 4 , and a fire-fighting agent spraying solenoid valve 2 is arranged on the fire-fighting agent spraying device.

[0038] The BMS controller module includes: BMU (Battery Management Unit), BCU (Battery Control Unit), BAU (Battery Analysis Unit);

[0039] BMU is the bottom control level, which is installed in the battery compartment. It monitors the temperature and voltage of the single battery cells and transmits the temperature and voltage information of the single battery cells to the upper-level BCU in real time through the CAN bus.

[0040] The BCU is the upper control level of the BMU and is disposed in the upper box 6 in the packaging shell 4;

[0041] The BCU collects the temperature and voltage values ​​of several single cells detected by the BMUs, detects the total voltage value of the battery pack 5 composed of multiple single cells, and transmits the temperature and voltage values ​​of the single cells and the total voltage value of the entire battery pack 5 to the superior BAU in real time through the CAN bus.

[0042] BAU is the upper control level of BCU and is arranged in the upper box 6 in the packaging shell 4;

[0043] BAU collects and summarizes the information of the lower-level BCU, and communicates with the signal processing system through the CAN bus, or through serial port communication or network port communication.

[0044] Specifically, the BMU includes: a temperature sensor 1, a primary voltage detection sensor, a primary MCU (micro control unit), a primary battery monitoring chip and a primary CAN communication module;

[0045] A temperature sensor 1 is arranged on the side wall of each single cell. The temperature sensor 1 is in close contact with the outer surface of the cell and senses the temperature of the cell by heat conduction.

[0046] The primary voltage detection sensor is electrically connected to the output end of the battery cell;

[0047] The primary battery monitoring chip is electrically connected to the temperature sensor 1 and the primary voltage detection sensor to collect the temperature and voltage signals of the battery cell in real time;

[0048] The first-level battery monitoring chip is electrically connected to the first-level MCU, and transmits the collected temperature and voltage signals to the first-level MCU;

[0049] The first-level MCU stores the temperature and voltage signals and transmits them to the upper-level BCU through the first-level CAN communication module;

[0050] The primary CAN communication module sends and receives data on the CAN bus.

[0051] More specifically, the temperature sensor 1 is an NTC thermistor; the NTC thermistor is mounted on the surface of a single cell to obtain the temperature of the cell;

[0052] The primary battery monitoring chip is the bq76PL45A chip, which supports the measurement of 6-16 lithium-ion batteries, including cobalt, manganese, phosphate series lithium batteries and fuel cells;

[0053] The first-level MCU is the LPC845M301JBD64 chip, which plays the main control and computing functions;

[0054] LPC845M301JBD64 is a 32-bit microcontroller based on the ARM Cortex-MO core, with a maximum frequency of 30MHz, 64KB of ROM and 16KB of RAM;

[0055] The first-level battery monitoring chip communicates with the first-level MCU via serial communication;

[0056] The output end of the NTC thermistor is connected to the AUX port of the bq76PL45A chip, that is, the temperature information collected by the NTC thermistor is directly sent to the bq76PL45A chip for processing, and then transmitted to the first-level MCU through serial communication.

[0057] The first-level CAN communication module uses the TCAN450-q1 chip, which has the function of transmitting and receiving, so that messages can be sent and received under the CAN protocol; sending commands through the SPI interface can start the sending of messages; at this time, checking the communication status or error information can be completed by reading the corresponding registers.

[0058] The interrupt pins of TCAN450-q1 enhance the flexibility of the system. It is up to the user to decide whether to use these pin functions. These pins can be used to indicate whether a valid message has been received or loaded into each receive buffer. If the user does not use these pins, the status register can also be accessed through the SPI interface to determine whether a valid message has been received or loaded into each receive buffer.

[0059] The first-level MCU controls TCAN450-q1 to realize the transmission and reception of data on the CAN bus; the first-level MCU and TCAN450-q1 use SPI communication; TCAN450-q1 has an FD controller and a transceiver; in the actual circuit, a 120Ω resistor is connected in parallel between CANH and CANL of TCAN450-q1, which can filter out high-frequency interference on the bus and also has a certain anti-electromagnetic radiation effect.

[0060] Specifically, the BCU includes: a secondary voltage detection sensor, a secondary MCU (micro control unit), a secondary battery monitoring chip and a secondary CAN communication module;

[0061] The secondary voltage detection sensor is electrically connected to the output end of the battery pack 5;

[0062] The secondary battery monitoring chip is electrically connected to the secondary voltage detection sensor to collect the voltage signal of the battery pack 5 in real time;

[0063] The secondary battery monitoring chip is electrically connected to the secondary MCU and transmits the collected voltage signal to the secondary MCU;

[0064] The primary CAN communication module is electrically connected to the secondary MCU. The primary MCU transmits the temperature and voltage signals of the single cell to the upper BCU through the primary CAN communication module.

[0065] The secondary MCU is electrically connected to the secondary CAN communication module, and transmits the temperature and voltage signals to the upper BAU through the secondary CAN communication module.

[0066] More specifically, the secondary MCU is the LPC845M301JBD64 chip, which performs the main control and computing functions;

[0067] The secondary battery monitoring chip is the bq76PL45A chip;

[0068] The secondary battery monitoring chip communicates with the secondary MCU via serial communication;

[0069] The secondary CAN communication module uses the TCAN450-q1 chip.

[0070] The BAU includes: a three-level MCU (micro control unit) and a three-level CAN communication module;

[0071] The third-level MCU transmits the lower-level BCU to the signal processing system through the second-level CAN communication module.

[0072] The signal processing system uses the JCMC series controller as the hardware basis to realize the software module functions, and its software modules include: acquisition module, logic control module, and display module.

[0073] The acquisition module communicates with the third-level CAN communication module, outputs indication signals and receives BAU data;

[0074] The display module is connected to an external display device to display the voltage, temperature, temperature change rate of the battery cell, the total voltage of the battery pack 5 and the status of the fire-fighting spray solenoid valve 2 .

[0075] The logic control module has a logic judgment function, which compares the battery cell temperature with the standard temperature to calculate the rate of change of the battery cell temperature to control the display module to display the temperature change and control the opening and closing state of the fire spray solenoid valve 2, thereby controlling the spray state of the fire-fighting agent.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A fire warning system for a lithium battery energy storage system, characterized in that: The fire warning system of the lithium battery energy storage system includes: a lithium battery PACK module, a BMS controller module arranged in the lithium battery PACK module to obtain battery cell temperature information, and a signal processing system that processes the temperature signal and outputs a control signal; The BMS controller module comprises a BMU unit, which is arranged in the battery compartment and is electrically connected to a temperature sensor (1) closely attached to the surface of the single cell and a primary voltage detection sensor arranged at the output end of the single cell, respectively, to monitor the temperature and voltage of the single cell; The BMS controller module further comprises a BCU unit, which is arranged in an upper box (6) in the packaging shell (4), receives the temperature value and voltage value of the single battery cell detected by the BMU unit through a CAN bus, and detects the total voltage value of a battery pack (5) composed of a plurality of single battery cells; The BMS controller module further comprises a BAU unit, which is arranged in an upper box (6) in the packaging shell (4); the BAU collects and summarizes the temperature value, voltage value and total voltage value information of the single battery cells in the BCU unit via a CAN bus, and communicates with the signal processing system via a CAN bus, serial port communication or network port communication; The lithium battery PACK module comprises a battery pack (5) composed of a plurality of battery cells and a packaging shell (4) arranged outside the battery pack (5), wherein the packaging shell (4) separates the battery pack (5) from the outside, and a plurality of horizontally arranged partitions are arranged inside the packaging shell, wherein a plurality of separated battery compartments are formed between the partitions, and two battery packs (5) are arranged in one battery compartment; The packaging shell (4) is in the form of a container. After the battery packs (5) are connected in parallel in pairs, a plurality of battery packs connected in parallel in pairs are connected in series to increase the capacity and high-voltage current output of the lithium battery energy storage system. A fire-fighting agent injection device is provided in the packaging shell (4), and a fire-fighting agent injection solenoid valve (2) is provided on the fire-fighting agent injection device. The BMU unit comprises: a first-level MCU, a first-level battery monitoring chip and a first-level CAN communication module; a temperature sensor (1) is provided on the side wall of each single battery cell, and the temperature sensor (1) is in close contact with the outer surface of the battery cell; the first-level battery monitoring chip is electrically connected to the temperature sensor (1), the first-level voltage detection sensor and the first-level MCU at the same time, collects temperature and voltage signals of the battery cell in real time, and transmits the collected temperature and voltage signals to the first-level MCU; the first-level MCU stores the temperature and voltage signals and transmits them to the BCU unit through the first-level CAN communication module; The BCU unit comprises: a secondary voltage detection sensor, a secondary MCU, a secondary battery monitoring chip and a secondary CAN communication module; the secondary voltage detection sensor is electrically connected to the output end of the battery pack (5); the secondary battery monitoring chip is electrically connected to the secondary voltage detection sensor and the secondary MCU, collects voltage signals of the battery pack (5) in real time, and transmits the collected voltage signals to the secondary MCU; the primary CAN communication module is electrically connected to the secondary MCU, and the primary MCU transmits temperature and voltage signals of the single cell to the BCU unit via the primary CAN communication module; the secondary MCU is electrically connected to the secondary CAN communication module, and transmits temperature and voltage signals to the BAU unit via the secondary CAN communication module; The BAU unit includes: a three-level MCU and a three-level CAN communication module. The three-level MCU transmits the signal of the BCU unit to the signal processing system through the two-level CAN communication module.

2. A fire warning system for a lithium battery energy storage system according to claim 1, characterized in that: The temperature sensor (1) is an NTC thermistor, the primary battery monitoring chip communicates with the primary MCU via a serial port communication method, and the secondary battery monitoring chip communicates with the secondary MCU via a serial port communication method.

3. The fire warning system of a lithium battery energy storage system according to claim 1, characterized in that: The signal processing system includes an acquisition module, a logic control module, and a display module; the acquisition module communicates with the three-level CAN communication module, outputs an indication signal, and receives data from the BAU unit; The display module is externally connected to an external display device and is used to display the voltage, temperature, temperature change rate of the battery cell, the total voltage of the battery pack (5), and the state of the fire-fighting spray solenoid valve (2).

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