CN117318228A - Battery core protection device, energy storage system and battery core protection method - Google Patents

Abstract

The invention provides a battery cell protection device, an energy storage system and a battery cell protection method, wherein a first switch is connected in parallel with a battery cell circuit, a second switch is connected in series with at least one pole of a battery cell, and when a main control module receives battery cell fault information, the first switch is controlled to be turned on and the second switch is controlled to be turned off, so that the battery cell is broken to be separated from a battery cell group, meanwhile, the first switch provides a short circuit channel, an electric signal is continuously transmitted through the first switch, the whole battery pack can still continue to work, the problem that the whole battery pack exits from working is avoided, and the working efficiency of the energy storage system is improved.

Description

Battery core protection device, energy storage system and battery core protection method

Technical field

The present invention relates to the technical field of energy storage, and specifically relates to a battery core protection device, an energy storage system and a battery core protection method.

Background technique

At present, the internal structure of the energy storage system is that cells are connected in series to form battery packs or packs, and packs are connected in series to form clusters. Several clusters are connected in parallel and connected to the energy storage inverter (English: Power Conversion System, abbreviation: PCS). ). The current protection measures for battery cells are at pack level or cluster level, but they do not involve battery level protection.

Contents of the invention

In view of the problems in the prior art, the purpose of the present invention is to provide a battery core protection device, an energy storage system and a battery core protection method to solve the technical problems related to battery core level protection in related technologies.

An embodiment of the present invention provides a battery core protection device, which includes:

Cell circuit, first switch, sensor and main control module;

The battery circuit includes a battery core with a positive electrode and a negative electrode, and a second switch connected in series with at least one electrode of the positive electrode and the negative electrode. The second switch has a first control terminal, a first terminal and a second terminal, and the first terminal and the second terminal are The two terminals are connected in series with the battery core, and the first control terminal is connected to the main control module;

The first switch has a second control terminal, a third terminal and a fourth terminal, the second control terminal is connected to the main control module, and the first switch is connected in parallel with the battery circuit through the third terminal and the fourth terminal;

The sensor is connected to the battery core and establishes a communication connection with the main control module. The sensor is set to detect faults in the battery core and transmit the detection signal to the main control module;

The main control module is connected to the first control terminal and the second control terminal. The main control module is configured to control the conduction of the first switch through the first control terminal and control the conduction of the first switch through the second control terminal when the detection signal shows a battery core failure. The second switch is turned off.

In some embodiments, the first switch is a MOS transistor, the gate of the MOS transistor serves as the first control terminal, the source of the MOS transistor serves as the first terminal, and the drain of the MOS transistor serves as the second terminal.

In some embodiments, the second switch is a MOS transistor, the gate of the MOS transistor serves as the second control terminal, the source of the MOS transistor serves as the third terminal, and the drain of the MOS transistor serves as the fourth terminal.

In some embodiments, the sensor includes at least one of a gas sensor, a temperature sensor, a voltage collection device, and a current collection device.

In some embodiments, the cell protection device further includes:

The power supply is connected to the battery core and the main control module, and is set to draw power from the battery core and supply power to the main control module.

In some embodiments, the power supply is a DC-DC converter.

In some embodiments, the cell protection device further includes:

The backup interface is connected to the main control module and is configured to access the external power supply and communication module to upload the detection information of the battery core through the communication module.

In some embodiments, a wireless communication connection is provided between the main control module and the sensor.

An embodiment of the present disclosure also provides an energy storage system, which includes any of the above battery cell protection devices.

Embodiments of the present disclosure also provide a battery core protection method. The battery core protection method is implemented based on the telecommunications protection device of any of the above embodiments. The battery core protection method is applied to the main control module. The battery core protection method includes:

Receive the fault detection signal of the battery core from the sensor;

When the fault detection signal indicates a fault, the second switch is controlled to be turned off and the first switch is controlled to be turned on.

The battery core protection device, energy storage system and battery core protection method provided by the present invention have the following advantages:

By connecting the first switch in parallel to the battery core circuit and connecting the second switch in series to at least one pole of the battery core, when the main control module receives the battery core fault information, it controls the first switch to turn on and the second switch to turn off. In this way, the battery The core is disconnected to separate from the battery pack. At the same time, the first switch provides a short-circuit channel. The electrical signal continues to be transmitted through the first switch. The entire battery pack can continue to work, avoiding the problem of the entire battery pack quitting work and improving the work of the energy storage system. efficiency.

Description of drawings

Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of the non-limiting embodiments with reference to the following drawings.

Figure 1 is a circuit diagram of a related art battery protection module for lithium batteries;

Figure 2 shows a circuit structure diagram of a battery core protection device provided by an embodiment of the present disclosure;

Figure 3 is a schematic diagram of electrical symbols when the first switch shown in Figure 2 is a PMOS tube;

Figure 4 is a schematic diagram of the electrical symbols when the first switch shown in Figure 2 is a PNP transistor;

Figure 5 is a flow chart of a battery core protection method provided by an embodiment of the present disclosure.

Detailed ways

The following describes the implementation of the present application through specific examples. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the present application. The present application can also be implemented or applied in different specific embodiments. Various details in the present application can also be modified or changed in various ways according to different viewpoints and application systems without departing from the spirit of the present application. It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments of this application can be combined with each other.

The embodiments of the present application will be described in detail below with reference to the accompanying drawings, so that those skilled in the technical field to which this application belongs can easily implement them. The present application can be embodied in many different forms and is not limited to the embodiments described here.

In this specification, reference to the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like is intended to be in conjunction with a specific feature of the embodiment or example representation. , structures, materials or features are included in at least one embodiment or example of the present application. Furthermore, the specific features, structures, materials, or characteristics shown may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine the different embodiments or examples represented in this application and the features of the different embodiments or examples unless they are inconsistent with each other.

In addition, the terms "first" and "second" are only used for expression purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the expressions of this application, "plurality" means two or more than two, unless otherwise expressly and specifically limited.

In order to clearly describe the present application, components irrelevant to the description are omitted, and the same or similar components throughout the specification are given the same reference numerals.

Although not differently defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Terms defined in commonly used dictionaries are additionally interpreted to have meanings that are consistent with the content of relevant technical documents and current prompts. As long as they are not defined, they shall not be overly interpreted to have ideal or very formulaic meanings.

Figure 1 shows a circuit diagram of a related art battery protection module for lithium batteries. When the discharge voltage is undervoltage, the charging voltage of battery cell 1 is too high, or the temperature is too high, control circuit 2 controls MOS tube 3 to turn off. Control the negative output of the cell.

The battery protection module of the related technology is only suitable for consumer-grade batteries with small capacity and current output within 20A. These batteries are small in size and output, so the protection circuit can be implemented with a dedicated IC (Integrated Circuit).

The capacity of battery cells used in the energy storage industry must reach more than 100AH, and even more may reach more than 300AH. The current of energy storage cells during charging and discharging is several hundred amps, so device selection and circuit design must be More rigorous. At the same time, since the cells in the energy storage system are connected in series, if one cell has a problem and is disconnected, the entire battery pack cannot be used.

Embodiments of the present disclosure propose a cell-level protection solution to ensure that even if one cell is disconnected due to a problem, the entire battery pack can continue to be used.

Figure 2 shows a circuit diagram of a battery core protection device provided by an embodiment of the present disclosure. As shown in Figure 2, the battery core protection device includes:

Battery core circuit 10, first switch 20, sensor 30 and main control module 40;

The battery cell circuit 10 includes a battery core 11 with a positive electrode and a negative electrode (not shown in the figure), and a second switch 12 connected in series with the positive electrode and the negative electrode. The second switch 12 has a first control terminal, a first terminal and a second terminal. (Not shown in the figure), the first end and the second end are connected in series with the battery core 11, and the first control end is connected to the main control module 40;

The first switch 20 has a second control terminal, a third terminal and a fourth terminal (not shown in the figure). The second control terminal is connected to the main control module 40. The first switch 20 is connected to the battery core through the third terminal and the fourth terminal. Circuit 10 is connected in parallel;

The sensor 30 is connected to the battery core 11 and establishes a communication connection with the main control module 40. The sensor 30 is configured to detect faults on the battery core 11 and transmit the detection signal to the main control module 40;

The main control module 40 is connected to the first control terminal and the second control terminal. The main control module 40 is configured to control the conduction of the first switch 20 through the first control terminal and the conduction of the first switch 20 through the second control terminal when the detection signal shows that the battery core 11 is faulty. The control end controls the second switch 12 to be turned off.

Using this embodiment, when the battery core 11 fails, the battery core 11 can be directly disconnected. At the same time, by turning on the first switch 20, the first switch 20 provides a short-circuit path, so that the electrical signal continues to be transmitted through the first switch 20, ensuring that Other cells in the battery pack including cell 11 can still work normally, allowing the entire battery pack to continue working and avoiding the problem of the entire battery pack shutting down.

This embodiment can be applied to high-power battery cells, and the installation method can be directly combined with the battery core to form an integrated battery core according to the battery core structure.

In the embodiment of the present disclosure, as shown in FIG. 3 , the first switch 20 is a MOS tube, the gate G of the MOS tube serves as the first control terminal, the source S of the MOS tube serves as the first terminal, and the drain D of the MOS tube serves as the first control terminal. as the second end.

The MOS tube shown in Figure 3 is an NMOS tube, and the current flows from the source S to the drain D. In another embodiment, the MOS transistor is a PMOS transistor, and the circuit flows from the drain to the source. During application, the connection mode of the first switch is set according to the type of MOS tube and the actual current direction.

In other embodiments of the present disclosure, as shown in FIG. 4 , the first switch 20 may also be a triode, with the base B serving as the first control terminal, the collector C serving as the first terminal, and the emitter E serving as the second terminal. Among them, the transistor shown in Figure 4 is a PNP type, and an NPN type can also be selected. During application, the connection mode of the first switch is set according to the actual current direction.

In the embodiment of the present disclosure, the second switch 12 shown in FIG. 2 can be a MOS tube. The gate of the MOS tube serves as the second control terminal, the source of the MOS tube serves as the third terminal, and the drain of the MOS tube serves as the fourth terminal. . Among them, the MOS tube is an NMOS tube or a PMOS tube.

In another embodiment, the second switch may also be a triode, with the base serving as the second control terminal, the collector serving as the third terminal, and the emitter serving as the fourth terminal. Wherein, the transistor can be of PNP type or NPN type.

In the embodiment shown in Figure 2, the positive and negative poles of the battery core 11 are respectively connected to different second switches 12. This ensures that when one of the second switches 20 fails, the other second switch 20 can also remain normally open. The battery core 11 is separated from the pack, thereby improving the success rate of the battery core protection device in this embodiment.

In another embodiment, a second switch can also be connected to one of the positive electrode and the negative electrode of the battery core, and the first terminal and the second terminal are connected in series with the battery core.

Therefore, a second switch can be connected to at least one of the positive and negative electrodes of the battery core, and the first and second terminals are connected in series with the battery core.

In the embodiment of the present disclosure, a computer program can be built into the main control module 40, and the fault detection signals from each sensor 4 are processed by running the computer program to determine whether the battery core 11 is faulty, so as to respond, for example, when it is determined that there is a fault. In the case of battery cells, a control signal is sent to the first switch 20 and the second switch 12 . Furthermore, the fault type of the battery core 11 can also be judged by running a computer program, such as whether it is irreversible, and the fault can be reported in a timely manner.

In another embodiment, the main control module 40 may report an alarm signal when the battery core 11 fails.

In one embodiment, the main control module 40 can select a microcontroller unit (MCU), also called a single-chip microcomputer (English: single-chip microcomputer), which combines a central processing unit, a memory, and a timer/counter. ), various input and output interfaces, etc. are integrated into a microcomputer on an integrated circuit chip. During application, the corresponding computer program is written into the MCU.

In the embodiment of the present disclosure, as shown in FIG. 2 , the sensor 30 may include a gas sensor 31 , a temperature sensor 32 , a voltage collection device 33 and a current collection device 34 .

In a corresponding embodiment, the gas sensor 31 is configured to measure abnormal gas concentration around the battery core. For example, gases such as carbon monoxide, hydrogen, and carbon dioxide are produced during combustion in the battery core 31. At this time, the gas sensor 31 collects the gas concentration of these combustion gases, and transmits the gas concentration as a detection signal to the main control module 40. The main control module 40 sets To compare the collected gas concentration with the threshold and send a control signal to the first control end and the second control end when the gas concentration exceeds the standard.

In one embodiment, the gas sensor is a converter that converts a certain gas volume fraction into a corresponding electrical signal, which includes semiconductor sensors, solid electrolyte gas sensors, contact combustion gas sensors, electrochemical gas sensors and optical gas sensor.

The gas sensor 31 of this embodiment uses a solid electrolyte gas sensor. This sensor element conducts ions to a solid electrolyte diaphragm, which is called an electrochemical cell. It is divided into cation conduction and anion conduction. It is a highly selective sensor and has been studied extensively. What has been put into practical use is the zirconia solid electrolyte sensor. Its mechanism is to use the potential difference between the two batteries on both sides of the diaphragm to be equal to the potential of the concentration difference battery.

In one embodiment, the temperature sensor 32 collects the temperature value in the battery core 11 and transmits it to the main control module 40 . The main control module 40 determines whether the temperature of the battery core 11 is too high based on the temperature value collected in real time, such as whether it exceeds the temperature threshold, and can control the battery core 11 to leave the pack when the temperature is too high, and can report a high temperature warning at the same time.

In one embodiment, the voltage collection device 33 and the current collection device 34 are used to collect electrical signals, and the main control module 40 performs abnormality judgment on the electrical signals to determine whether there is a fault in the battery core 11 .

In the embodiment of the present disclosure, the gas sensor 31 is installed on the cover of the battery core 11 and extends into the inside of the cover to collect the gas in the battery core 11 .

In the embodiment of the present disclosure, as shown in Figure 2, the battery core protection device further includes:

The power supply 5 is connected to the battery core 11 and the main control module 40 and is configured to take power from the battery core 11 and supply power to the main control module 40 .

In this embodiment, the battery core 11 is the power supply of the main control module 40 , and the power supply 5 is configured to take power from the battery core 11 and provide power to the main control module 40 . This eliminates the need for external power supply, which helps reduce wiring complexity.

In one embodiment, the power supply 5 is a DC-to-DC converter, also known as a DC-DC converter or a DC transformer. It is a circuit or electromechanical device for converting electrical energy. It can convert DC ( DC) power supply is converted into DC (or approximately DC) power supply of different voltages.

A DC-DC converter is used to convert the DC power output by the battery core 11 into a DC power supply 5 with a corresponding voltage. The output voltage of the power supply 5 is adapted to the main control module 40 .

In the embodiment of the present disclosure, as shown in Figure 2, the battery core protection device also includes:

The backup interface 6 is connected to the main control module 40 and is configured to access an external power supply and a communication module (not shown in the figure) to upload the detection information of the battery core through the communication module.

In one embodiment, the backup interface 6 is used to activate the backup interface 6 and rely on an external power source to power the main control module 40 when the battery core 11 fails and becomes unavailable and the main control module 40 cannot work normally. At the same time, the fault detection information of the battery core 11 is uploaded to the upper device through the communication module, so that the faulty battery core 11 can be processed in a timely manner.

Therefore, this embodiment can detect battery core faults in a timely manner and eliminate the faults.

In the embodiment of the present disclosure, a wireless communication connection or a wired communication connection is provided between the main control module 40 and each sensor 30 . For wireless communication connection, a wireless communication module can be installed in each sensor 30 to communicate with the main control module 40 through the wireless communication module to transmit fault detection information of the battery core 11 to the main control module 40 .

In corresponding embodiments, wireless communication connections can reduce wiring, which not only reduces costs but also reduces product wiring redundancy.

An embodiment of the present disclosure also provides an energy storage system, which includes the battery core protection device of the above embodiment. In the energy storage system, these cell protection devices are connected in series through the cells 11. These cell protection devices can share a main control module 40, or each cell protection device can be configured with a corresponding main control module 40, or Some cell protection devices may share one main control module 40 .

Figure 5 is a flow chart of a battery core protection method provided by an embodiment of the present disclosure. The battery core protection method is implemented based on the battery core protection device shown in Figure 2, and is specifically applied to the main control module 40, as shown in Figure 5. The battery core protection method includes but is not limited to the following steps:

Step 510: Receive the fault detection signal for the battery core from the sensor;

Step 520: When the fault detection signal indicates a fault, control the second switch to be turned off and the first switch to be turned on.

Using this method, when a battery core fails, by controlling the second switch to open, the faulty battery core is separated from the pack where it is located, and at the same time, the first switch is controlled to be turned on, then the first switch provides a short-circuit channel, and the electrical signal continues to pass through the first switch. Make the transfer. In this case, the pack where the faulty battery core is located can continue to work externally, reducing the performance degradation of the energy storage system.

In one embodiment, when a fault detection signal is obtained from a sensor, it can also be determined based on the fault detection signal whether the battery core has failed. For this, please refer to the above content about the sensor and will not go into details here.

In one embodiment, when the fault detection signal indicates a fault, it can not only automatically respond to control the battery core to leave the pack, but also report a fault notification signal. The fault notification signal can include fault warning information to remind relevant personnel. Troubleshoot promptly.

The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be concluded that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all of them should be regarded as belonging to the protection scope of the present invention.

Claims (10)

1. A battery core protection device, characterized in that it includes: Cell circuit, first switch, sensor and main control module; The battery cell circuit includes a battery core with a positive electrode and a negative electrode, and a second switch connected in series with at least one electrode of the positive electrode and the negative electrode. The second switch has a first control terminal, a first terminal and a second terminal. , the first end and the second end are connected in series with the battery core, and the first control end is connected to the main control module; The first switch has a second control end, a third end and a fourth end. The second control end is connected to the main control module. The first switch is connected to the main control module through the third end and the fourth end. Cell circuits are connected in parallel; The sensor is connected to the battery core and establishes a communication connection with the main control module. The sensor is configured to perform fault detection on the battery core and transmit a detection signal to the main control module; The main control module is connected to the first control terminal and the second control terminal, and the main control module is configured to control all battery cells through the first control terminal when the detection signal indicates that the battery core is faulty. The first switch is turned on and the second switch is controlled to turn off through the second control terminal. 2. The battery core protection device according to claim 1, characterized in that, The first switch is a MOS tube, the gate of the MOS tube serves as the first control terminal, the source of the MOS tube serves as the first terminal, and the drain of the MOS tube serves as the second end. 3. The battery core protection device according to claim 1, characterized in that, The second switch is a MOS tube, the gate of the MOS tube serves as the second control terminal, the source of the MOS tube serves as the third terminal, and the drain of the MOS tube serves as the fourth end. 4. The battery core protection device according to claim 1, characterized in that, The sensor includes at least one of a gas sensor, a temperature sensor, a voltage collection device, and a current collection device. 5. The battery core protection device according to claim 1, characterized in that the battery core protection device further includes: A power supply is connected to the battery core and the main control module, and is configured to take power from the battery core and supply power to the main control module. 6. The battery core protection device according to claim 5, characterized in that the power supply is a DC-DC converter. 7. The battery core protection device according to claim 5, characterized in that the battery core protection device further includes: A backup interface is connected to the main control module and is configured to access an external power supply and a communication module to upload detection information of the battery core through the communication module. 8. The battery core protection device according to claim 1, characterized in that, A wireless communication connection is provided between the main control module and the sensor. 9. An energy storage system, characterized by comprising the cell protection device according to any one of claims 1-7. 10. A battery core protection method, characterized in that the battery core protection method is implemented based on the battery core protection device according to any one of claims 1 to 8, and the battery core protection method is applied to the battery core protection device. Main control module, the battery core protection method includes: Receive a fault detection signal for the battery core from the sensor; When the fault detection signal indicates a fault, the second switch is controlled to be turned off and the first switch is controlled to be turned on.