Battery pack and energy storage system
By adopting the circuit topology of the first resistor to the fifth resistor, the voltage-regulating diode and the switching tube in the battery pack, the fast overcurrent protection of the battery cell is achieved, and the problems of slow response speed, large size and high cost in the prior art are solved, and the reliability and safety of the battery pack are improved.
Patent Information
- Application Number
- CN202411889977.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-04-11
AI Technical Summary
The overcurrent protection of the battery cells in existing battery packs has problems such as slow response speed, large size and high cost.
Using a circuit topology including a first resistor to a fifth resistor, a first voltage regulator diode, a first switching tube and a second switching tube, the relevant devices are immediately turned off when an overcurrent occurs in the battery cell, thereby disconnecting the circuit between the positive and negative electrodes of the battery cell to achieve overcurrent protection.
It realizes fast overcurrent protection of the battery cell, has fast response speed, simple circuit topology and low cost, and improves the reliability and safety of the battery pack.
Smart Images
Figure CN119813438A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of power electronics technology, and in particular to a battery pack and an energy storage system. Background Art
[0002] The battery pack includes cells. During the process of charging or discharging the cells, the charging current or discharging current of the cells may be greater than the current threshold (also called cell overcurrent or overcurrent). For example, when the cells are discharging and the load is abnormal, the discharge current of the cells may be greater than the current threshold, which can be called the overcurrent protection point of the cells. When the charging current or discharging current of the cells is greater than the current threshold, the cells will be damaged and even endanger personal safety.
[0003] The battery pack may include a circuit composed of a resistor and an operational amplifier to detect the charging current or discharging current of the battery cell, or may include a Hall current sensor or a mutual inductor to detect the charging current or discharging current of the battery cell. Then, when it is detected that the charging current or discharging current of the battery cell is greater than the current threshold, the battery cell is controlled to be disconnected from the load or the DC power supply, thereby achieving overcurrent protection of the battery cell, avoiding damage to the battery cell, avoiding endangering personal safety, and improving the reliability and safety of the battery pack.
[0004] However, operational amplifiers have time delays and slow response speeds. Hall current sensors are expensive, have small bandwidths, and slow response speeds. Transformers are large in size and costly. In summary, in the process of using the above-mentioned method to detect the charging current or discharging current of the battery cell to achieve overcurrent protection of the battery cell, there are problems such as slow response speed, large size, and high cost. Therefore, how to achieve overcurrent protection of the battery cell in the battery pack with fast response speed, simple circuit topology, and low cost has become an urgent problem to be solved. Summary of the invention
[0005] The embodiments of the present application provide a battery pack and an energy storage system, which solve the problem of how to achieve overcurrent protection of battery cells in a battery pack with fast response speed, simple circuit topology and low cost.
[0006] In order to achieve the above purpose, the embodiment of the present application adopts the following technical solution: In the first aspect of the embodiment of the present application, a battery pack is provided, which includes: a battery cell. A first switch tube, a first resistor and a second resistor, the emitter or source of the first switch tube is connected to the positive electrode of the battery cell, and the first resistor and the second resistor are connected in series between the collector or drain of the first switch tube and the negative electrode of the battery cell. A third resistor, a second switch tube, a first voltage regulator diode, a fourth resistor and a fifth resistor, the third resistor is connected between the negative electrode of the battery cell and the emitter or source of the second switch tube, the collector or drain of the second switch tube is connected to the anode of the first voltage regulator diode, and the fourth resistor and the fifth resistor are connected in series between the cathode of the first voltage regulator diode and the positive electrode of the battery cell. The connection point of the first resistor and the second resistor is connected to the base or gate of the second switch tube, the connection point of the fourth resistor and the fifth resistor is connected to the base or gate of the first switch tube, and the positive electrode of the battery cell and the anode of the first voltage regulator diode are used to connect to a load or a DC power supply. Among them, the first switch tube is a PNP transistor, PMOS or PIGBT, and the second switch tube is NMOS or NIGBT.
[0007] Based on this solution, the battery pack utilizes the characteristics of the first resistor to the fifth resistor, the first voltage zener diode, the first switch tube and the second switch tube. When an overcurrent occurs in the battery cell, the first voltage zener diode, the first switch tube and the second switch tube can be immediately turned off to disconnect the circuit between the positive and negative electrodes of the battery cell to achieve overcurrent protection of the battery cell. Compared with the process of using operational amplifiers, Hall current sensors or mutual inductors to achieve overcurrent protection of battery cells, these devices will bring problems such as slow response speed, large size and high cost. The device used in the embodiment of the present application has a faster response speed, smaller size and lower cost, so that overcurrent protection of the battery cell can be achieved, and the response speed is fast, the circuit topology is simple and the cost is low.
[0008] In combination with the first aspect, in a possible implementation, the battery pack also includes a second zener diode, an anode of the second zener diode is connected to the negative electrode of the battery cell, and a cathode of the second zener diode is connected to the base or gate of the second switch tube.
[0009] Based on this solution, the second voltage regulator diode can protect the second switch tube, thereby improving the reliability of the battery pack.
[0010] In combination with the first aspect, in a possible implementation, the battery pack further includes a switch connected between the positive electrode of the battery cell and the collector or drain of the first switching tube.
[0011] Based on this solution, when an overcurrent occurs in the battery cell, the second switch tube is turned off. After a period of time, when the overcurrent phenomenon of the battery cell disappears, the normal working state of the battery cell can be restored by closing the switch.
[0012] In combination with the first aspect, in a possible implementation, the battery pack further includes a switch and a sixth resistor, and the switch and the sixth resistor are connected in series between the positive electrode of the battery cell and the base or gate of the second switch tube.
[0013] Based on this solution, when an overcurrent occurs in the battery cell, the second switch tube is turned off. After a period of time, when the overcurrent phenomenon of the battery cell disappears, the normal working state of the battery cell can be restored by closing the switch.
[0014] In combination with the first aspect, in a possible implementation manner, the switch is used to be periodically turned on, so that the second switch tube is periodically turned on.
[0015] Based on this solution, the switch is periodically turned on to make the second switch tube periodically turned on, so that when overcurrent occurs in the battery cell, the second switch tube is turned off. After a period of time, when the overcurrent phenomenon of the battery cell disappears, the normal working state of the battery cell can be restored in time.
[0016] In combination with the first aspect, in a possible implementation manner, the switch is a photoelectric coupler.
[0017] Based on this solution, a photoelectric coupler is used as a switch to isolate the strong current circuit from the weak current circuit, reduce the interference of the strong current circuit on the weak current circuit, and improve the stability of the battery pack.
[0018] In combination with the first aspect, in a possible implementation, the battery pack further includes a signal generator, an output end of the signal generator is connected to the controlled end of the switch, and the signal generator is an inverter.
[0019] Based on this solution, a control signal is generated by a signal generator to control the periodic conduction of the switch, so that the second switch tube is periodically turned on, so that when an overcurrent occurs in the battery cell, the second switch tube is turned off, and after a period of time, the overcurrent phenomenon of the battery cell disappears, and the normal working state of the battery cell can be restored in time. Secondly, the use of an inverter as a signal generator does not require design software, which can reduce the complexity of the design, and the circuit is simple and small in size, which can reduce the cost of the battery pack.
[0020] In a second aspect of an embodiment of the present application, an energy storage system is provided, which includes a battery pack and a power converter connected to the battery pack. The battery pack is a battery pack as described in the first aspect or any possible implementation of the first aspect, and the power converter is used to convert direct current power output by the battery pack.
[0021] The description of the second aspect in this application can refer to the detailed description of the first aspect; and the beneficial effects of the second aspect can refer to the analysis of the beneficial effects of the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 A schematic diagram of a circuit topology of a battery pack provided in an embodiment of the present application; Figure 2 A schematic diagram of another circuit topology of a battery pack provided in an embodiment of the present application; Figure 3 A schematic diagram of a circuit topology of another battery pack provided in an embodiment of the present application; Figure 4 A schematic diagram of a circuit topology of another battery pack provided in an embodiment of the present application; Figure 5 A schematic diagram of a circuit topology of another battery pack provided in an embodiment of the present application; Figure 6 A circuit topology diagram of another battery pack provided in an embodiment of the present application. DETAILED DESCRIPTION
[0023] The making and using of various embodiments will be discussed in detail below. The specific embodiments discussed are only used to illustrate specific ways to implement and use the present description and technology, and do not limit the scope of the present application.
[0024] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art.
[0025] Various circuits or other components may be described or referred to as being "configured to" perform one or more tasks. In this case, "configured to" is used to imply structure by indicating that the circuit / component includes structure (e.g., circuitry) that performs the one or more tasks during operation. Thus, even when the specified circuit / component is not currently operational (e.g., not turned on), the circuit / component may be referred to as being configured to perform the task. Circuits / components used with the wording "configured to" include hardware, such as circuits that perform an operation, etc.
[0026] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. In the present application, "multiple" means two or more. The character " / " generally indicates that the objects associated with each other are in an "or" relationship. In addition, in the embodiments of the present application, the words "first", "second", etc. do not limit the quantity and order.
[0027] In this application, the words "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the words "exemplary" or "for example" is intended to present the related concepts in a concrete way.
[0028] In order to solve the problem of how to achieve overcurrent protection of battery cells in a battery pack with fast response speed, simple circuit topology and low cost, an embodiment of the present application provides a battery pack. Compared with the process of using operational amplifiers, Hall current sensors or mutual inductors to achieve overcurrent protection of battery cells, these devices will bring about the problems of slow response speed, large size and high cost. In the battery pack provided by the embodiment of the present application, overcurrent protection of battery cells is achieved through switching tubes, resistors and Zener diodes (ZD), thereby achieving overcurrent protection of battery cells in the battery pack with fast response speed, simple circuit topology and low cost.
[0029] like Figure 1 As shown, the battery pack 100 provided in the embodiment of the present application can be used as an independent device, and the positive and negative electrodes of the battery pack 100 are used to connect to a load or a DC power supply 200. When the load or the DC power supply 200 is a load, it can include a motor in an electric vehicle. When the load or the DC power supply 200 is a DC power supply, it can include a photovoltaic (PV) array.
[0030] Reference Figure 1 The battery pack 100 provided in the embodiment of the present application can also be applied to the energy storage system 300, which also includes a power converter 310 connected to the battery pack 100, and the power converter 310 is used to connect to the load or the DC power supply 200. The power converter 310 is used to convert the DC power output by the DC power supply to power the battery pack 100, or to convert the DC power output by the battery pack 100 to power the load. The type of the energy storage system 300 may include at least one of a photovoltaic energy storage system, a wind power generation energy storage system, or a power station energy storage system, which is not limited in the embodiment of the present application.
[0031] In a possible embodiment, the energy storage system 300 may include a plurality of battery packs 100, and the plurality of battery packs 100 may be connected in series, or in parallel, or in a hybrid connection, wherein the hybrid connection refers to a connection method that includes both a series connection and a parallel connection. The embodiment of the present application does not limit the specific number of battery packs 100 included in the energy storage system 300, and the specific connection method between the plurality of battery packs 100. Figure 1 In the embodiment of the present application, an energy storage system 300 including a battery pack 100 is used as an example for illustrative description.
[0032] Continue to refer to Figure 1The battery pack 100 provided in the embodiment of the present application includes: a battery cell 110. A first switch tube Q1, a first resistor R1 and a second resistor R2, wherein the emitter (E) or source (S) of the first switch tube Q1 is connected to the positive electrode of the battery cell 110, and the first resistor R1 and the second resistor R2 are connected in series between the collector (C) or drain (D) of the first switch tube Q1 and the negative electrode of the battery cell 110. A third resistor R3, a second switch tube Q2, a first voltage regulator diode ZD1, a fourth resistor R4 and a fifth resistor R5, wherein the third resistor R3 is connected between the negative electrode of the battery cell 110 and the emitter or source of the second switch tube Q2, the collector or drain of the second switch tube Q2 is connected to the anode of the first voltage regulator diode ZD1, and the fourth resistor R4 and the fifth resistor R5 are connected in series between the cathode of the first voltage regulator diode ZD1 and the positive electrode of the battery cell 110. The connection point between the first resistor R1 and the second resistor R2 is connected to the base (base, B) or gate (gate, G) of the second switch tube Q2, the connection point between the fourth resistor R4 and the fifth resistor R5 is connected to the base or gate of the first switch tube Q1, and the positive electrode of the battery cell 110 and the anode of the first voltage regulator diode ZD1 are used to be connected to a load or a DC power supply 200.
[0033] The first switch tube Q1 is a PNP transistor, a P-channel metal-oxide-semiconductor field-effect transistor (PMOS) or a P-channel insulated gate bipolar transistor (PIGBT), and the second switch tube Q2 is an NMOS or a NIGBT. The embodiment of the present application does not limit the specific types of the first switch tube Q1 and the second switch tube Q2. Figure 1 In the embodiment of the present application, the first switch tube Q1 is a PNP transistor and the second switch tube Q2 is an NMOS for exemplary description.
[0034] Continue to refer to Figure 1 In the process of charging the battery cell 110 with a DC power supply or discharging the battery cell 110 to a load, the process of implementing overcurrent protection of the battery cell 110 in the battery pack 100 provided in the embodiment of the present application includes: When the battery cell 110 does not have an overcurrent, the voltage drop of the third resistor R3 is less than or equal to the voltage threshold, the reverse voltage of the first voltage zener diode ZD1 is greater than or equal to the voltage stabilization value of the first voltage zener diode ZD1, and the first voltage zener diode ZD1 is in a conducting state. The voltage applied to the base of the first switch tube Q1 after voltage division by the fourth resistor R4 and the fifth resistor R5 is less than the voltage of the emitter of the first switch tube Q1, and the first switch tube Q1 is in a conducting state. The voltage applied to the gate of the second switch tube Q2 after voltage division by the first resistor R1 and the second resistor R2 will control the second switch tube Q2 to be in a conducting state. Thus, a loop can be formed between the positive and negative electrodes of the battery cell 110, and the battery cell 110 can be charged or discharged normally.
[0035] In the event of overcurrent in the battery cell 110, the voltage drop of the third resistor R3 is greater than the above-mentioned voltage threshold, the reverse voltage of the first voltage zener diode ZD1 is less than the voltage stabilization value of the first voltage zener diode ZD1, and the first voltage zener diode ZD1 will be turned off. The fourth resistor R4 and the fifth resistor R5 no longer divide the voltage, the voltage applied to the base of the first switch tube Q1 is equal to the voltage applied to the emitter of the first switch tube Q1, and the first switch tube Q1 will be turned off. The first resistor R1 and the second resistor R2 no longer divide the voltage, and the voltage applied to the gate of the second switch tube Q2 will control the second switch tube Q2 to turn off. Thus, the loop between the positive and negative electrodes of the battery cell 110 can be disconnected to achieve overcurrent protection of the battery cell 110.
[0036] In a possible embodiment, the voltage threshold can be adjusted by selecting a third resistor R3 with a different resistance value, or selecting a first voltage regulator diode ZD1 with a different voltage regulation value, so that the overcurrent protection point of the battery cell 110 can be adjusted. The embodiment of the present application does not limit the specific resistance value of the third resistor R3 and the specific voltage regulation value of the first voltage regulator diode ZD1, and does not limit the specific value of the voltage regulation threshold.
[0037] In a possible embodiment, the battery pack 100 may include a plurality of battery cells 110, and the plurality of battery cells 110 may be connected in series, or may be connected in parallel, or may be connected in mixed series. The embodiment of the present application does not limit the specific number of battery cells 110 included in the battery pack 100, and the specific connection method between the plurality of battery cells 110. Figure 1 In the embodiment of the present application, a battery pack 100 including a battery cell 110 is used as an example for illustrative description.
[0038] In a possible embodiment, the above-mentioned resistor (any one of the first resistor R1 to the fifth resistor R5) may include multiple resistors, and the multiple resistors may be connected in series, in parallel, or in mixed connection. The embodiment of the present application does not limit the specific number of resistors included in the resistor and the specific connection method between the multiple resistors.
[0039] In a possible embodiment, the battery pack 100 may further include a capacitor connected in parallel with the above-mentioned resistor (any one of the first resistor R1 to the fifth resistor R5), and the capacitor is used for decoupling, so as to stabilize the voltage of the battery cell 110 and improve the anti-interference ability of the battery pack 100.
[0040] In a possible embodiment, the circuit topology and scheme for overcurrent protection of the battery cell 110 provided in the embodiment of the present application can also be applied to devices such as optimizers, photovoltaic inverters or uninterruptible power supplies (UPS) that require overcurrent protection of the DC bus, and the embodiment of the present application is not limited to this.
[0041] The battery pack 100 provided in the embodiment of the present application utilizes the characteristics of the first resistor R1 to the fifth resistor R5, the first voltage zener diode ZD1, the first switch tube Q1 and the second switch tube Q2. When an overcurrent occurs in the battery cell 110, the first voltage zener diode ZD1, the first switch tube Q1 and the second switch tube Q2 can be immediately turned off, so that the circuit between the positive electrode and the negative electrode of the battery cell 110 is disconnected, so as to achieve overcurrent protection of the battery cell 110. Compared with the process of using operational amplifiers, Hall current sensors or mutual inductors to achieve overcurrent protection of the battery cell, these devices will bring about the problems of slow response speed, large size and high cost. The device used in the embodiment of the present application has a faster response speed, smaller size and lower cost, so that the overcurrent protection of the battery cell 110 can be achieved, and the response speed is fast, the circuit topology is simple and the cost is low.
[0042] In a possible embodiment, Figure 2 , which is a circuit topology diagram of a battery pack 100 provided in an embodiment of the present application. The battery pack 100 also includes a second voltage stabilizing diode ZD2, the anode of the second voltage stabilizing diode ZD2 is connected to the negative electrode of the battery cell 110, and the cathode of the second voltage stabilizing diode ZD2 is connected to the gate of the second switch tube Q2.
[0043] In the battery pack 100 provided in the embodiment of the present application, the second voltage stabilizing diode ZD2 can protect the second switch tube Q2, and can improve the reliability of the battery pack 100. For example, when there is no overcurrent in the battery cell 110, the DC power supply charges the battery cell 110, or the battery cell 110 discharges to the load, and the voltage between the positive and negative electrodes of the battery cell 110 is overvoltage or fluctuates, the second voltage stabilizing diode ZD2 can stabilize the voltage applied to the gate of the second switch tube Q2, thereby protecting the second switch tube Q2.
[0044] In a possible embodiment, Figure 3FIG. 1 is a schematic diagram of a circuit topology of another battery pack 100 provided in an embodiment of the present application. The battery pack 100 further includes a switch K connected between the positive electrode of the battery cell 110 and the collector of the first switch tube Q1. Alternatively, Figure 4 , which is a circuit topology diagram of another battery pack 100 provided in an embodiment of the present application, wherein the battery pack 100 further includes a switch K and a sixth resistor R6 connected in series, wherein the switch K and the sixth resistor R6 are connected in series between the positive electrode of the battery cell 110 and the gate of the second switch tube Q2. Figure 3 or Figure 4 When an overcurrent occurs in the battery cell 110, the second switch tube Q2 is turned off. After a period of time, when the overcurrent phenomenon of the battery cell 110 disappears, the second switch tube Q2 can be turned on by closing the switch K to restore the normal working state of the battery cell 110.
[0045] In a possible embodiment, the switch K and the sixth resistor R6 connected in series include: one end of the sixth resistor R6 is connected to the positive electrode of the battery cell 110, the other end of the sixth resistor R6 is connected to one end of the switch K, and the other end of the switch K is connected to the gate of the second switch tube Q2. Figure 4 , one end of the switch K is connected to the positive electrode of the battery cell 110, the other end of the switch K is connected to one end of the sixth resistor R6, and the other end of the sixth resistor R6 is connected to the gate of the second switch tube Q2. The embodiment of the present application does not limit the specific series connection mode of the switch K and the sixth resistor R6. The embodiment of the present application uses the specific series connection mode of the switch K and the sixth resistor R6 as follows: Figure 4 The series connection shown in FIG. 1 is used as an example for illustrative description. In the following embodiments of the present application, the circuit topology of the battery pack 100 is as follows Figure 4 The circuit topology of the battery pack 100 shown is taken as an example for exemplary description.
[0046] In one possible embodiment, continue to refer to Figure 4 The switch K is used to be periodically turned on so that the second switch tube Q2 is periodically turned on.
[0047] Exemplarily, when an overcurrent occurs in the battery cell 110 and the second switch tube Q2 is turned off, the switch K is periodically turned on so that the second switch tube Q2 is periodically turned on. If the overcurrent phenomenon of the battery cell 110 disappears when the second switch tube Q2 is turned on, the first voltage zener diode ZD1 and the first switch tube Q1 will resume conduction, and the second switch tube Q2 will no longer be affected by the switch K and remain in the on state, so that a loop can be formed between the positive and negative electrodes of the battery cell 110, and the battery cell 110 can resume the normal charging or discharging working state in time. If the overcurrent phenomenon of the battery cell 110 does not disappear when the second switch tube Q2 is turned on, the first voltage zener diode ZD1 and the first switch tube Q1 will continue to remain turned off, and the second switch tube Q2 will continue to follow the switch K to turn on or off.
[0048] In a possible embodiment, the switch K is a photoelectric coupler, or the switch K may include a switch tube. The embodiment of the present application does not limit the specific type of the switch K. The embodiment of the present application takes the switch K as a photoelectric coupler as an example for illustrative description.
[0049] For example, refer to Figure 4 In the case where the switch K is a photocoupler, the switch K includes a light emitting diode (LED) LED and a phototransistor (PT) PT, and the phototransistor PT can also be called a photosensitive transistor. Compared with the switch tube, the photocoupler can isolate the strong current (high voltage and high current) circuit between the positive and negative electrodes of the battery cell 110 from the weak current (low voltage and low current) circuit at the controlled end of the photocoupler, thereby reducing the interference of the strong current circuit on the weak current circuit and improving the stability of the battery pack 100.
[0050] In a possible embodiment, Figure 5 As shown, the battery pack 100 may include both the second voltage stabilizing diode ZD2 and the switch K, or, as shown in FIG. Figure 6 As shown, the battery pack 100 may include a second voltage stabilizing diode ZD2, and a switch K and a sixth resistor R6 connected in series, which is not limited in the embodiment of the present application.
[0051] In the battery pack 100 provided in the embodiment of the present application, the switch K is periodically turned on, so that the second switch tube Q2 is periodically turned on, so that when an overcurrent occurs in the battery cell 110, the second switch tube Q2 is turned off, and after a period of time, when the overcurrent phenomenon of the battery cell 110 disappears, the normal working state of the battery cell 110 can be restored in time. Secondly, using a photocoupler as the switch K can isolate the strong current circuit from the weak current circuit, reduce the interference of the strong current circuit on the weak current circuit, and improve the stability of the battery pack 100.
[0052] In one possible embodiment, continue to refer to Figure 4 The battery pack 100 further includes a signal generator (SG) SG, the output end of the signal generator SG is connected to the controlled end of the switch K, and the signal generator SG is used to generate a control signal to control the switch K to be periodically turned on.
[0053] In a possible embodiment, the signal generator SG is a phase inverter, or the signal generator SG includes a microcontroller unit (MCU) or a digital signal processing (DSP) chip, and the microcontroller may also be called a microcontroller unit or a single-chip microcomputer. The embodiment of the present application does not limit this. The embodiment of the present application takes the signal generator SG as an inverter, and the inverter is a dual-channel inverter as an example for illustrative description. Compared with using an MCU or DSP as the signal generator SG, using an inverter as the signal generator SG does not require design software, which can reduce design complexity, and the circuit is simple and small in size, which can reduce the cost of the battery pack 100.
[0054] For example, continue to refer to Figure 4 In the case where the signal generator SG is a dual-channel inverter 120, the two output ends of the dual-channel inverter 120 are connected to the anode and cathode of the light-emitting diode LED. The dual-channel inverter 120 is used to generate a square wave signal to control the light-emitting diode LED to emit light periodically, thereby controlling the phototransistor PT to be periodically turned on, so that the switch K is periodically turned on. The period of the square wave signal can be adjusted by changing the peripheral circuit of the dual-channel inverter 120 to adjust the period of the switch K being turned on. The specific process can refer to the prior art, and the embodiments of the present application will not be repeated here.
[0055] The battery pack 100 provided in the embodiment of the present application generates a control signal through the signal generator SG to control the periodic conduction of the switch K, so that the second switch tube Q2 is periodically turned on, so that when an overcurrent occurs in the battery cell 110, the second switch tube Q2 is turned off, and after a period of time, when the overcurrent phenomenon of the battery cell 110 disappears, the normal working state of the battery cell 110 can be restored in time. Secondly, the use of an inverter as the signal generator SG does not require design software, which can reduce the complexity of the design, and the circuit is simple and small in size, which can reduce the cost of the battery pack 100.
[0056] Based on this, refer to Figure 1 The present application also provides an energy storage system 300. The energy storage system 300 includes a battery pack 100 and a power converter 310 connected to the battery pack 100. The circuit topology of the battery pack 100 is as described above. Figures 1 to 6 The circuit topology of the battery pack 100 shown in any of the figures, the power converter 310 is used to convert the DC power output by the DC power supply to power the battery pack 100, or to convert the DC power output by the battery pack 100 to power the load.
[0057] The above detailed description of the battery pack 100 and the analysis of the beneficial effects can be correspondingly referred to the energy storage system 300, and the embodiments of the present application will not be repeated here.
[0058] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. A battery pack, characterized in that: The battery pack comprises: Battery cells; A first switch tube, a first resistor and a second resistor, wherein the emitter or source of the first switch tube is connected to the positive electrode of the battery cell, and the first resistor and the second resistor are connected in series between the collector or drain of the first switch tube and the negative electrode of the battery cell; a third resistor, a second switch tube, a first voltage-stabilizing diode, a fourth resistor and a fifth resistor, wherein the third resistor is connected between the negative electrode of the battery cell and the emitter or source of the second switch tube, the collector or drain of the second switch tube is connected to the anode of the first voltage-stabilizing diode, the fourth resistor and the fifth resistor are connected in series between the cathode of the first voltage-stabilizing diode and the positive electrode of the battery cell, the connection point of the first resistor and the second resistor is connected to the base or gate of the second switch tube, the connection point of the fourth resistor and the fifth resistor is connected to the base or gate of the first switch tube, and the positive electrode of the battery cell and the anode of the first voltage-stabilizing diode are used to be connected to a load or a DC power supply; The first switch tube is a PNP transistor, a PMOS or a PIGBT; The second switch tube is NMOS or NIGBT.
2. The battery pack according to claim 1, characterized in that: The battery pack further includes a second zener diode, an anode of the second zener diode is connected to the negative electrode of the battery cell, and a cathode of the second zener diode is connected to the base or gate of the second switch tube.
3. The battery pack according to claim 1 or 2, characterized in that: The battery pack further includes a switch connected between the positive electrode of the battery cell and the collector or drain of the first switch tube.
4. The battery pack according to claim 1 or 2, characterized in that: The battery pack further includes a switch and a sixth resistor, and the switch and the sixth resistor are connected in series between the positive electrode of the battery cell and the base or gate of the second switch tube.
5. The battery pack according to claim 3 or 4, characterized in that: The switch is used to be periodically turned on, so that the second switch tube is periodically turned on.
6. The battery pack according to any one of claims 3 to 5, characterized in that: The switch is a photocoupler.
7. The battery pack according to any one of claims 3 to 6, characterized in that: The battery pack further includes a signal generator, an output end of the signal generator is connected to the controlled end of the switch, and the signal generator is an inverter.
8. An energy storage system, characterized in that: The energy storage system includes a battery pack and a power converter connected to the battery pack. The battery pack is the battery pack as described in any one of claims 1 to 7. The power converter is used to convert the direct current output by the battery pack.