Battery detection device and energy storage system

Abstract

The utility model discloses a battery detection device and an energy storage system, and relates to the technical field of battery detection. The energy storage system comprises a battery pack, a charging input end and a discharging output end, the battery pack comprises a plurality of battery cells, and the battery detection device comprises a main control circuit; the voltage detection circuit is used for detecting the working voltage of the plurality of battery cells and outputting a voltage detection signal; the charging switch circuit is used for receiving the charging switch control signal output by the main control circuit and connecting or disconnecting a path between the charging input end and the input end of the battery pack; the discharge switch circuit is used for receiving the discharge switch control signal output by the main control circuit and connecting or disconnecting a path between the discharge output end and the output end of the battery pack; a cue circuit; wherein the main control circuit is used for receiving a voltage detection signal and outputting a corresponding charging switch control signal and / or a discharging switch control signal and / or a prompt signal. The utility model aims to improve the working safety of the energy storage system.

Description

Technical Field

[0001] This utility model relates to the field of battery testing technology, and in particular to a battery testing device and energy storage system. Background Technology

[0002] In energy storage systems, the fire protection system is a crucial component, encompassing fire detection systems, audible and visual alarm systems, perfluorohexanone (PFH) suppression systems, combustible gas detection systems, and explosion-proof fan systems. The fire detection system performs compartment-level detection (smoke, temperature, CO, H2), compartment-level VOC and flame detection, and battery pack-level combined detection (smoke, temperature, CO, VOC). The primary alarm logic of the fire detection system includes six alarms: smoke alarm, temperature alarm, primary warning from the combined detector, gas detector alarm (H2, CO, VOC), manual fire alarm button press, and flame detector alarm. Triggering any one of these alarms triggers the system's primary fire alarm. In actual operation, when the fire protection system detects these faults, the battery pack has already exhibited significant thermal runaway. The earlier the intervention time for battery thermal runaway, the better the effect of suppressing battery thermal runaway and the better the overall safety performance of the system.

[0003] The thermal runaway process of a battery pack includes the following four stages: the initiation stage, the thermal propagation stage, the thermal runaway acceleration stage, and the combustion and explosion stage. Fire detection systems based on the above schemes can often only detect battery anomalies in the thermal runaway acceleration stage and the combustion and explosion stage, but cannot detect battery anomalies in the initiation stage and the thermal propagation stage. Utility Model Content

[0004] The main purpose of this invention is to provide a battery testing device and an energy storage system, which aims to improve the safety of the energy storage system.

[0005] To achieve the above objectives, the present invention proposes a battery testing device applied to an energy storage system. The energy storage system includes a battery pack, a charging input terminal for receiving electrical energy, and a discharging output terminal for outputting electrical energy. The battery pack includes multiple battery cells. The battery testing device includes:

[0006] Main control circuit;

[0007] A voltage detection circuit is provided, wherein the input terminal of the voltage detection circuit is electrically connected to multiple battery cells respectively, and the output terminal of the voltage detection circuit is electrically connected to the main control circuit; the voltage detection circuit is used to detect the operating voltage of multiple battery cells and output a voltage detection signal.

[0008] A charging switch circuit, wherein the input terminal of the charging switch circuit is electrically connected to the charging input terminal, the controlled terminal of the charging switch circuit is electrically connected to the main control circuit, and the output terminal of the charging switch circuit is electrically connected to the input terminal of the battery pack; the charging switch circuit is used to receive the charging switch control signal output by the main control circuit, and to connect or disconnect the path between the charging input terminal and the input terminal of the battery pack.

[0009] The discharge switch circuit has its output terminal electrically connected to the discharge output terminal, the controlled terminal of the charging switch circuit electrically connected to the main control circuit, and the input terminal of the charging switch circuit electrically connected to the output terminal of the battery pack. The discharge switch circuit is used to receive the discharge switch control signal output by the main control circuit and to connect or disconnect the path between the discharge output terminal and the output terminal of the battery pack.

[0010] A prompting circuit, the input terminal of which is electrically connected to the main control circuit; the prompting circuit is used to receive the prompting control signal output by the main control circuit and output a corresponding prompting signal.

[0011] The main control circuit is used to receive the voltage detection signal and output the corresponding charging switch control signal and / or discharging switch control signal and / or prompt signal.

[0012] In one embodiment, the voltage detection circuit includes:

[0013] A first filter circuit, the input terminal of which is electrically connected to the battery cell; the first filter circuit is used to filter the input voltage and output it.

[0014] A first voltage regulator circuit, wherein the input terminal of the first voltage regulator circuit is electrically connected to the output terminal of the first filter circuit; the first voltage regulator circuit is used to limit the input voltage within a first preset voltage and output it.

[0015] The first analog-to-digital converter circuit has its input terminal electrically connected to the output terminal of the first voltage regulator circuit, and its output terminal electrically connected to the main control circuit. The first analog-to-digital converter circuit is used to output the input voltage signal after analog-to-digital conversion.

[0016] In one embodiment, the first filter circuit includes a first resistor, a second resistor, and a first capacitor; the first voltage regulator circuit includes a first Zener diode.

[0017] Wherein, the first end of the first resistor is electrically connected to the first end of the battery cell, and the second end of the first resistor is electrically connected to the first end of the first capacitor, the cathode of the first Zener diode, and the first input terminal of the analog-to-digital converter circuit; the first end of the second resistor is electrically connected to the second end of the battery cell, and the second end of the second resistor is electrically connected to the second end of the first capacitor, the anode of the first Zener diode, and the second input terminal of the analog-to-digital converter circuit.

[0018] In one embodiment, the battery detection device further includes a temperature detection circuit disposed on the surface of the battery cell, and the output terminal of the temperature detection circuit is electrically connected to the main control circuit; the temperature detection circuit is used to detect the temperature of the surface of the battery cell and output a temperature detection signal.

[0019] In one embodiment, the temperature detection circuit includes:

[0020] A temperature acquisition circuit is disposed on the surface of the battery cell; the temperature acquisition circuit is used to acquire the temperature value of the surface of the battery cell and output a temperature acquisition signal.

[0021] The second voltage regulator circuit has its input terminal electrically connected to the output terminal of the temperature acquisition circuit; the second voltage regulator circuit is used to limit the input voltage within a second preset voltage and output it.

[0022] The second filter circuit has its input terminal electrically connected to the output terminal of the second voltage regulator circuit; the second filter circuit is used to filter the input voltage and output it.

[0023] The second analog-to-digital converter circuit has its input terminal electrically connected to the second filter circuit and its output terminal electrically connected to the main control circuit; the second analog-to-digital converter circuit is used to output the input voltage signal after analog-to-digital conversion.

[0024] In one embodiment, the temperature detection circuit further includes a signal amplification circuit, the input terminal of which is electrically connected to the output terminal of the second filter circuit, and the output terminal of which is electrically connected to the input terminal of the second analog-to-digital conversion circuit; the signal amplification circuit is used to amplify and process the voltage signal output by the second filter circuit before outputting it.

[0025] In one embodiment, the temperature acquisition circuit includes a thermistor and a third resistor; the second voltage regulator circuit includes a second Zener diode; the second filter circuit includes a fourth resistor, a second capacitor, and a third capacitor; and the signal amplification circuit includes an operational amplifier and a fourth capacitor.

[0026] Wherein, the first end of the thermistor is electrically connected to the second end of the third resistor, the first end of the second Zener diode, the first end of the second capacitor, and the first end of the fourth resistor; the second end of the thermistor is electrically connected to the first end of the third resistor; the second end of the second Zener diode is electrically connected to the second end of the second capacitor, the second end of the third capacitor, and the ground terminal; the second end of the fourth resistor is electrically connected to the first end of the third capacitor and the non-inverting input terminal of the operational amplifier; the inverting input terminal of the operational amplifier is electrically connected to the output terminal of the operational amplifier, the input terminal of the second analog-to-digital converter circuit, and the first end of the fourth capacitor; and the second end of the fourth capacitor is electrically connected to the ground terminal.

[0027] In one embodiment, the battery detection device includes a passive balancing circuit, a first terminal of which is electrically connected to a first terminal of the battery cell, a second terminal of which is electrically connected to a second terminal of the battery cell, and a controlled terminal of which is electrically connected to a main control circuit; the passive balancing circuit is used to regulate the charge balance of multiple battery cells.

[0028] The main control circuit is also used to output an equalization control signal to enable the passive equalization circuit to operate.

[0029] In one embodiment, the passive equalization circuit includes a fifth resistor, a sixth resistor, a seventh resistor, a first switching transistor, and a third Zener diode;

[0030] Specifically, the first end of the fifth resistor is electrically connected to the first end of the sixth resistor and the second end of the battery cell; the second end of the fifth resistor is electrically connected to the second end of the sixth resistor and the second end of the first switching transistor; the first end of the first switching transistor is electrically connected to the first end of the battery cell and the cathode of the third Zener diode; the second end of the first switching transistor is electrically connected to the anode of the third Zener diode and the first end of the seventh resistor; and the second end of the seventh resistor is electrically connected to the main control circuit.

[0031] This utility model also proposes an energy storage system, which includes a battery pack, a charging input terminal for receiving electrical energy, a discharging output terminal for outputting electrical energy, and a battery detection device as described in any of the above.

[0032] The battery pack includes multiple battery cells.

[0033] This invention employs a voltage detection circuit to detect the voltage of multiple cells within a battery pack in an energy storage system, thereby obtaining the voltage status of each cell. It is understood that when a cell is operating abnormally, its voltage will fluctuate abnormally. The main control circuit receives the voltage detection signal output from the voltage detection circuit and matches the corresponding voltage value with a preset voltage range to confirm whether a cell is malfunctioning. When the main control circuit confirms that a cell is in an abnormal operating state, it outputs a charging switch control signal or a discharging switch control signal to the charging switch circuit or discharging switch circuit, respectively, to stop the energy storage system from charging or discharging. Furthermore, the main control circuit also outputs a prompt control signal to the prompt circuit, prompting management personnel to promptly confirm and maintain the system, thus improving the safety of the energy storage system. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the modules of the battery testing device of this utility model;

[0036] Figure 2 This is a circuit diagram of an embodiment of the battery testing device of this utility model;

[0037] Figure 3 This is a schematic diagram of a module of an embodiment of the battery testing device of this utility model;

[0038] Figure 4 This is a circuit diagram of yet another embodiment of the battery testing device of this utility model;

[0039] Figure 5 This is a circuit diagram of another embodiment of the battery testing device of this utility model.

[0040] Explanation of icon numbers:

[0041] 10. Main control circuit; 20. Voltage detection circuit; 21. First filter circuit; 22. First voltage regulator circuit; 30. Charging switch circuit; 40. Discharging switch circuit; 50. Indication circuit; 60. Temperature detection circuit; 61. Temperature acquisition circuit; 62. Second voltage regulator circuit; 63. Second filter circuit; 64. Signal amplification circuit; R1-R7, first resistor-seventh resistor; C1-C4, first capacitor-fourth capacitor; D1-D3, first voltage regulator diode-third voltage regulator diode; RT, thermistor; U1, operational amplifier; Q1, first switching transistor.

[0042] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0043] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0044] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0045] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0046] In energy storage systems, the fire protection system is a crucial component, encompassing fire detection systems, audible and visual alarm systems, perfluorohexanone (PFH) suppression systems, combustible gas detection systems, and explosion-proof fan systems. The fire detection system performs compartment-level detection (smoke, temperature, CO, H2), compartment-level VOC and flame detection, and battery pack-level combined detection (smoke, temperature, CO, VOC). The primary alarm logic of the fire detection system includes six alarms: smoke alarm, temperature alarm, primary warning from the combined detector, gas detector alarm (H2, CO, VOC), manual fire alarm button press, and flame detector alarm. Triggering any one of these alarms triggers the system's primary fire alarm. In actual operation, when the fire protection system detects these faults, the battery pack has already exhibited significant thermal runaway. The earlier the intervention time for battery thermal runaway, the better the effect of suppressing battery thermal runaway and the better the overall safety performance of the system.

[0047] The thermal runaway process of a battery pack includes the following four stages: the initiation stage, the thermal propagation stage, the thermal runaway acceleration stage, and the combustion and explosion stage. Fire detection systems based on the above schemes can often only detect battery anomalies in the thermal runaway acceleration stage and the combustion and explosion stage, but cannot detect battery anomalies in the initiation stage and the thermal propagation stage.

[0048] Therefore, refer to Figures 1 to 5 This utility model proposes a battery testing device for use in an energy storage system. The energy storage system includes a battery pack, a charging input terminal for receiving electrical energy, and a discharging output terminal for outputting electrical energy. The battery pack includes multiple battery cells. The battery testing device includes:

[0049] Main control circuit 10;

[0050] A voltage detection circuit 20 is provided, the input terminals of which are electrically connected to multiple battery cells, and the output terminal of which is electrically connected to the main control circuit 10. The voltage detection circuit 20 is used to detect the operating voltage of multiple battery cells and output a voltage detection signal.

[0051] A charging switch circuit 30 is provided, wherein the input terminal of the charging switch circuit 30 is electrically connected to the charging input terminal, the controlled terminal of the charging switch circuit 30 is electrically connected to the main control circuit 10, and the output terminal of the charging switch circuit 30 is electrically connected to the input terminal of the battery pack; the charging switch circuit 30 is used to receive the charging switch control signal output by the main control circuit 10, and to connect or disconnect the path between the charging input terminal and the input terminal of the battery pack.

[0052] The discharge switch circuit 40 has its output terminal electrically connected to the discharge output terminal, its controlled terminal electrically connected to the main control circuit 10, and its input terminal electrically connected to the output terminal of the battery pack. The discharge switch circuit 40 is used to receive the discharge switch control signal output by the main control circuit 10 and to connect or disconnect the path between the discharge output terminal and the output terminal of the battery pack.

[0053] The prompting circuit 50 is electrically connected to the main control circuit 10. The prompting circuit 50 is used to receive the prompting control signal output by the main control circuit 10 and output the corresponding prompting signal.

[0054] The main control circuit 10 is used to receive the voltage detection signal and output the corresponding charging switch control signal and / or discharging switch control signal and / or prompt signal.

[0055] In this embodiment, the main control circuit 10 can be implemented using PLC (Programmable Logic Controller), MCU (Microcontroller Unit), DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), SOC (System On Chip), etc.

[0056] It is important to understand that external impacts to the battery pack can cause the cell separator to puncture, and prolonged use of the cell can lead to lithium plating on the electrode surface puncturing the separator, resulting in an internal short circuit and a surge in internal current. Detecting the cell voltage can clearly reveal a voltage drop exceeding the normal range of 2.5-3.65V. Therefore, the voltage detection circuit 20 can confirm whether the cell's operating state is abnormal by detecting its voltage.

[0057] In this embodiment, the voltage detection circuit 20 can be implemented using a voltage divider circuit, a differential amplifier circuit, a comparator circuit, etc. The voltage divider circuit reduces the voltage to be measured proportionally to a range suitable for the input of the measuring instrument (such as an ADC) by connecting two or more resistors in series. For example, using two resistors in series, with the measurement point located between the two resistors, the voltage drop calculated using Ohm's law is a portion of the voltage to be measured. Optionally, the voltage detection circuit 20 includes: a first filter circuit 21, the input terminal of which is electrically connected to the battery cell; the first filter circuit 21 is used to filter and output the input voltage; a first voltage regulator circuit 22, the input terminal of which is electrically connected to the output terminal of the first filter circuit 21; the first voltage regulator circuit 22 is used to limit the input voltage within a first preset voltage and output it; a first analog-to-digital converter circuit, the input terminal of which is electrically connected to the output terminal of the first voltage regulator circuit 22, and the output terminal of which is electrically connected to the main control circuit 10; the first analog-to-digital converter circuit is used to output the input voltage signal after analog-to-digital conversion. The filter circuit can be implemented using an RC filter circuit, an LC filter circuit, etc.; the voltage regulator circuit can be implemented using a Zener diode, a linear regulator, etc. Furthermore, the first filter circuit 21 includes a first resistor R1, a second resistor R2, and a first capacitor C1; the first voltage regulator circuit 22 includes a first Zener diode D1; wherein, the first end of the first resistor R1 is electrically connected to the first end of the battery cell, and the second end of the first resistor R1 is electrically connected to the first end of the first capacitor C1, the cathode of the first Zener diode D1, and the first input terminal of the analog-to-digital converter circuit; the first end of the second resistor R2 is electrically connected to the second end of the battery cell, and the second end of the second resistor R2 is electrically connected to the second end of the first capacitor C1, the anode of the first Zener diode D1, and the second input terminal of the analog-to-digital converter circuit. The output voltage of the battery cell is first filtered by the first-order RC circuit composed of the first resistor R1, the second resistor R2, and the first capacitor C1, and then passed through the first Zener diode D1 before being input to the first analog-to-digital converter circuit, so that the analog-to-digital converter circuit can safely and stably obtain the corresponding voltage signal. The main control circuit 10 obtains an accurate voltage detection signal by being electrically connected to the output terminal of the first analog-to-digital converter circuit.

[0058] In this embodiment, the charging switch circuit 30 can be implemented using at least one switching transistor, such as a MOSFET, IGBT, thyristor, transistor, or power transistor, and / or using at least one switching device, such as a contactor, circuit breaker, or relay. The charging switch circuit 30 is connected in series between the charging input terminal and the battery pack input terminal. Upon receiving a charging switch control signal from the main control circuit 10, it can either open or close the path between the charging input terminal and the battery pack input terminal, thereby starting or stopping the charging operation of the battery pack in the energy storage system. Furthermore, when the battery pack in the energy storage system is charging, if the main control circuit 10 receives a voltage detection signal and confirms that the battery cells are in an abnormal state, the main control circuit 10 outputs a charging switch control signal to the charging switch circuit 30, causing the charging switch circuit 30 to disconnect the path between the charging input terminal and the battery pack input terminal.

[0059] In this embodiment, the discharge switch circuit 40 can be implemented using at least one switching transistor, such as a MOSFET, IGBT, thyristor, transistor, or power transistor, and / or using at least one switching device, such as a contactor, circuit breaker, or relay. The discharge switch circuit 40 is connected in series between the discharge output terminal and the battery pack output terminal. Upon receiving the discharge switch control signal from the main control circuit 10, it can either open or close the path between the discharge output terminal and the battery pack output terminal, thereby starting or interrupting the discharge operation of the battery pack in the energy storage system. Furthermore, when the battery pack in the energy storage system is in a discharge state, if the main control circuit 10 receives a voltage detection signal and confirms that the battery cells are in an abnormal state, the main control circuit 10 outputs a discharge switch control signal to the discharge switch circuit 40, causing the discharge switch circuit 40 to disconnect the path between the discharge input terminal and the battery pack output terminal.

[0060] In this embodiment, the prompting circuit 50 can be implemented using a voice prompting circuit 50, a visual prompting circuit 50, etc. The voice prompting circuit 50 can be implemented using an energy storage module combined with a microphone; the visual prompting circuit 50 can be implemented using an LED indicator circuit, an LCD display circuit, etc. After receiving the voltage detection signal and confirming that the current cell's operating state is normal, the main control circuit 10 outputs a corresponding prompting control signal to the prompting circuit 50, causing the prompting circuit 50 to output a corresponding prompting signal. Management personnel can confirm the current operating state of the energy storage system through this prompting signal. Similarly, when the cell's operating state is abnormal, the prompting circuit 50 will also receive the corresponding prompting control signal output by the main control circuit 10, and then output a corresponding prompting signal so that management personnel can perform timely maintenance.

[0061] Voltage detection circuit 20 is used to detect the voltage of multiple cells in the battery pack of the energy storage system, thereby obtaining the voltage status of multiple cells. It is understood that when a cell is in an abnormal operating state, its voltage will fluctuate abnormally. The main control circuit 10 receives the voltage detection signal output by the voltage detection circuit 20 and matches the corresponding voltage value with a preset voltage range to confirm whether a cell is malfunctioning. When the main control circuit 10 confirms that a cell is in an abnormal operating state, it will output a charging switch control signal or a discharging switch control signal to the charging switch circuit 30 or the discharging switch circuit 40 according to the current operating state of the energy storage system, so that the energy storage system stops charging or discharging. In addition, the main control circuit 10 will also output a prompt control signal to the prompt circuit 50, so that the prompt circuit 50 outputs a corresponding prompt signal to remind management personnel to promptly confirm maintenance, thereby improving the safety of the energy storage system.

[0062] refer to Figure 2 and Figure 4 In one embodiment of the present invention, the battery detection device further includes a temperature detection circuit 60, which is disposed on the surface of the battery cell and the output terminal of the temperature detection circuit 60 is electrically connected to the main control circuit 10; the temperature detection circuit 60 is used to detect the temperature of the surface of the battery cell and output a temperature detection signal.

[0063] In this embodiment, the temperature detection circuit 60 can be implemented using a detection circuit based on a thermistor, such as a resistor voltage divider circuit based on an NTC resistor or an NTC probe, or a resistor voltage divider circuit based on a PTC resistor or a PTC probe. Optionally, the temperature detection circuit 60 can also be implemented using a temperature sensor, such as an infrared temperature sensor or a thermocouple temperature sensor. Multiple temperature detection circuits 60 can be used, and these circuits can be located at different positions on the surface of the battery cell. The main control circuit 10 can determine multiple temperature values ​​based on the multiple temperature detection signals and calculate the actual ambient temperature using a preset temperature algorithm, such as averaging or weighted calculation, thereby improving the accuracy of detecting the battery cell's operating temperature.

[0064] Optionally, the temperature detection circuit 60 includes:

[0065] Temperature acquisition circuit 61 is disposed on the surface of the battery cell; the temperature acquisition circuit 61 is used to acquire the temperature value of the surface of the battery cell and output a temperature acquisition signal.

[0066] The second voltage regulator circuit 62 has its input terminal electrically connected to the output terminal of the temperature acquisition circuit 61; the second voltage regulator circuit 62 is used to limit the input voltage within a second preset voltage and output it.

[0067] The second filter circuit 63 has its input terminal electrically connected to the output terminal of the second voltage regulator circuit 62; the second filter circuit 63 is used to filter the input voltage and output it.

[0068] The second analog-to-digital converter circuit has its input terminal electrically connected to the second filter circuit 63 and its output terminal electrically connected to the main control circuit 10. The second analog-to-digital converter circuit is used to output the input voltage signal after analog-to-digital conversion.

[0069] In this embodiment, the temperature acquisition circuit 61 can be implemented using an NTC resistor or an NTC probe voltage divider circuit, or a PTC resistor or PTC probe voltage divider circuit, etc. The second voltage regulator circuit 62 can be implemented using a Zener diode, a linear regulator, etc. The second filter circuit 63 can be implemented using an RC filter circuit, an LC filter circuit, etc. Furthermore, the temperature detection circuit 60 also includes a signal amplification circuit 64. The input terminal of the signal amplification circuit 64 is electrically connected to the output terminal of the second filter circuit 63, and the output terminal of the signal amplification circuit 64 is electrically connected to the input terminal of the second analog-to-digital converter circuit. The signal amplification circuit 64 is used to amplify and process the voltage signal output by the second filter circuit 63 before outputting it. The signal amplification circuit 64 can be implemented using a differential amplifier, a power amplifier, etc. Specifically, the temperature acquisition circuit 61 includes a thermistor RT and a third resistor R3; the second voltage regulator circuit 62 includes a second Zener diode D2; the second filter circuit 63 includes a fourth resistor R4, a second capacitor C2, and a third capacitor C3; the signal amplification circuit 64 includes an operational amplifier U1 and a fourth capacitor C4; wherein, the first terminal of the thermistor RT is electrically connected to the second terminal of the third resistor R3, the first terminal of the second Zener diode D2, the first terminal of the second capacitor C2, and the first terminal of the fourth resistor R4; the second terminal of the thermistor RT is electrically connected to the first terminal of the third resistor R3; the second terminal of the second Zener diode D2 is electrically connected to the second terminal of the second capacitor C2, the second terminal of the third capacitor C3, and the ground terminal; the second terminal of the fourth resistor R4 is electrically connected to the first terminal of the third capacitor C3 and the non-inverting input terminal of the operational amplifier U1; the inverting input terminal of the operational amplifier U1 is electrically connected to the output terminal of the operational amplifier U1, the input terminal of the second analog-to-digital converter circuit, and the first terminal of the fourth capacitor C4; and the second terminal of the fourth capacitor C4 is electrically connected to the ground terminal.

[0070] refer to Figure 5In one embodiment of this utility model, the battery detection device includes a passive balancing circuit. The first terminal of the passive balancing circuit is electrically connected to the first terminal of the battery cell, the second terminal of the passive balancing circuit is electrically connected to the second terminal of the battery cell, and the controlled terminal of the passive balancing circuit is electrically connected to the main control circuit 10. The passive balancing circuit is used to regulate the charge balance of multiple battery cells.

[0071] The main control circuit 10 is also used to output an equalization control signal to enable the passive equalization circuit to operate.

[0072] It is understood that due to manufacturing differences, inconsistent usage environments, or varying degrees of aging, the cells in a battery pack may exhibit inconsistent voltages. A passive balancing circuit can balance the voltage of all battery cells by consuming energy from the high-voltage cells. Furthermore, an unbalanced battery pack can lead to overcharging or over-discharging of some cells, accelerating their aging process and potentially causing premature failure of the entire battery pack. By balancing the voltage of each battery cell, this situation can be avoided, thereby extending the overall lifespan of the battery pack. When each cell in the battery pack is operating at its optimal state, the efficiency of the entire system is improved. In addition, the balancing circuit helps prevent safety hazards such as thermal runaway caused by overcharging or discharging of individual cells. Therefore, this invention uses a passive balancing circuit to balance the charge in each cell of the battery pack.

[0073] Optionally, the passive balancing circuit includes a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first switch Q1, and a third Zener diode D3. The first terminal of the fifth resistor R5 is electrically connected to the first terminal of the sixth resistor R6 and the second terminal of the battery cell; the second terminal of the fifth resistor R5 is electrically connected to the second terminal of the sixth resistor R6 and the second terminal of the first switch Q1; the first terminal of the first switch Q1 is electrically connected to the first terminal of the battery cell and the cathode of the third Zener diode D3; the second terminal of the first switch Q1 is electrically connected to the anode of the third Zener diode D3 and the first terminal of the seventh resistor R7; and the second terminal of the seventh resistor R7 is electrically connected to the main control circuit 10. In this embodiment, the two ends of the battery cell are closed by a switch control circuit, forming a discharge circuit with two parallel resistors. Since the heat dissipation of a single resistor is limited, two resistors are used in parallel, effectively halving the resistance. Taking a cell voltage of 3.2V as an example, the rated discharge equalization current is 100mA. The third Zener diode D3 achieves voltage clamping, and the first switching transistor Q1 is turned on or off by receiving the control signal output by the main control circuit 10, thereby realizing the control of the passive equalization circuit.

[0074] This utility model also proposes an energy storage system, which includes a battery pack, a charging input terminal for receiving electrical energy, a discharging output terminal for outputting electrical energy, and a battery detection device as described in any of the above claims; wherein the battery pack includes multiple battery cells. It is worth noting that since the energy storage system of this utility model is based on the aforementioned battery detection device, the embodiments of the energy storage system of this utility model include all the technical solutions of all embodiments of the aforementioned battery detection device, and the achieved technical effects are exactly the same, and will not be repeated here.

[0075] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A battery detection device applied to an energy storage system, characterized in that, The energy storage system comprises a battery pack, a charging input end for receiving electric energy, and a discharging output end for outputting electric energy, the battery detection device comprises: a main control circuit; a voltage detection circuit, input ends of the voltage detection circuit are electrically connected with a plurality of the battery cells respectively, and an output end of the voltage detection circuit is electrically connected with the main control circuit; the voltage detection circuit is used for detecting working voltages of the plurality of battery cells and outputting voltage detection signals; a charging switch circuit, an input end of the charging switch circuit is electrically connected with the charging input end, a controlled end of the charging switch circuit is electrically connected with the main control circuit, and an output end of the charging switch circuit is electrically connected with an input end of the battery pack; the charging switch circuit is used for receiving a charging switch control signal output by the main control circuit, and turns on or turns off a path between the charging input end and the input end of the battery pack; a discharging switch circuit, an output end of the discharging switch circuit is electrically connected with the discharging output end, a controlled end of the discharging switch circuit is electrically connected with the main control circuit, and an input end of the discharging switch circuit is electrically connected with an output end of the battery pack; the discharging switch circuit is used for receiving a discharging switch control signal output by the main control circuit, and turns on or turns off a path between the discharging output end and the output end of the battery pack; a prompting circuit, an input end of the prompting circuit is electrically connected with the main control circuit; the prompting circuit is used for receiving a prompting control signal output by the main control circuit, and outputting a corresponding prompting signal; wherein the main control circuit is used for receiving the voltage detection signals, and outputting corresponding charging switch control signals and / or discharging switch control signals and / or prompting signals.

2. The battery detection apparatus according to claim 1, wherein The voltage detection circuit comprises: a first filter circuit, an input end of the first filter circuit is electrically connected with the battery cell; the first filter circuit is used for filtering and processing an input voltage and outputting; a first voltage stabilizing circuit, an input end of the first voltage stabilizing circuit is electrically connected with an output end of the first filter circuit; the first voltage stabilizing circuit is used for limiting an input voltage within a first preset voltage and outputting; a first analog-digital conversion circuit, an input end of the first analog-digital conversion circuit is electrically connected with an output end of the first voltage stabilizing circuit, and an output end of the first analog-digital conversion circuit is electrically connected with the main control circuit; the first analog-digital conversion circuit is used for converting an input voltage signal into a digital signal and outputting.

3. The battery detection apparatus of claim 2, wherein The first filter circuit comprises a first resistor, a second resistor, and a first capacitor; the first voltage stabilizing circuit comprises a first voltage stabilizing diode; wherein a first end of the first resistor is electrically connected with a first end of the battery cell, a second end of the first resistor is electrically connected with a first end of the first capacitor, a cathode of the first voltage stabilizing diode, and a first input end of the analog-digital conversion circuit; a first end of the second resistor is electrically connected with a second end of the battery cell, and a second end of the second resistor is electrically connected with a second end of the first capacitor, an anode of the first voltage stabilizing diode, and a second input end of the analog-digital conversion circuit.

4. The battery detection apparatus of claim 1, wherein The battery detection device further comprises a temperature detection circuit, which is arranged on the surface of the battery cell and has an output end electrically connected to the main control circuit; the temperature detection circuit is configured to detect the temperature of the surface of the battery cell and output a temperature detection signal.

5. The battery detection apparatus of claim 4, wherein The temperature detection circuit comprises: a temperature acquisition circuit, which is arranged on the surface of the battery cell and configured to acquire the temperature value of the surface of the battery cell and output a temperature acquisition signal; a second voltage stabilizing circuit, which has an input end electrically connected to the output end of the temperature acquisition circuit and is configured to limit the input voltage within a second preset voltage and output; a second filter circuit, which has an input end electrically connected to the output end of the second voltage stabilizing circuit and is configured to output after filtering the input voltage; a second analog-to-digital conversion circuit, which has an input end electrically connected to the second filter circuit and an output end electrically connected to the main control circuit; the second analog-to-digital conversion circuit is configured to output after analog-to-digital conversion of the input voltage signal.

6. The battery detection apparatus of claim 5, wherein The temperature detection circuit further comprises a signal amplification circuit, which has an input end electrically connected to the output end of the second filter circuit and an output end electrically connected to the input end of the second analog-to-digital conversion circuit; the signal amplification circuit is configured to output after amplification of the voltage signal output by the second filter circuit.

7. The battery detection apparatus of claim 6, wherein The temperature acquisition circuit comprises a thermistor and a third resistor; the second voltage stabilizing circuit comprises a second voltage stabilizing diode; the second filter circuit comprises a fourth resistor, a second capacitor and a third capacitor; the signal amplification circuit comprises an operational amplifier and a fourth capacitor; wherein the first end of the thermistor is electrically connected to the second end of the third resistor, the first end of the second voltage stabilizing diode, the first end of the second capacitor and the first end of the fourth resistor, and the second end of the thermistor is electrically connected to the first end of the third resistor; the second end of the second voltage stabilizing diode is electrically connected to the second end of the second capacitor, the second end of the third capacitor and a ground end; the second end of the fourth resistor is electrically connected to the first end of the third capacitor and the non-inverting input end of the operational amplifier; the inverting input end of the operational amplifier is electrically connected to the output end of the operational amplifier, the input end of the second analog-to-digital conversion circuit and the first end of the fourth capacitor; and the second end of the fourth capacitor is electrically connected to the ground end.

8. The battery detection apparatus of claim 1, wherein The battery detection device comprises a passive equalization circuit, which has a first end electrically connected to the first end of the battery cell, a second end electrically connected to the second end of the battery cell and a controlled end electrically connected to the main control circuit; the passive equalization circuit is configured to regulate the charge balance of the plurality of battery cells. The main control circuit is further configured to output an equalization control signal to enable the passive equalization circuit to work.

9. The battery detection apparatus of claim 8, wherein The passive equalization circuit comprises a fifth resistor, a sixth resistor, a seventh resistor, a first switch tube and a third voltage stabilizing diode; The first end of the fifth resistor is electrically connected with the first end of the sixth resistor and the second end of the battery cell, and the second end of the fifth resistor is electrically connected with the second end of the sixth resistor and the second end of the first switch tube; the first end of the first switch tube is electrically connected with the first end of the battery cell and the cathode of the third voltage stabilizing diode, and the second end of the first switch tube is electrically connected with the anode of the third voltage stabilizing diode and the first end of the seventh resistor; and the second end of the seventh resistor is electrically connected with the main control circuit.

10. An energy storage system characterized by, The energy storage system comprises a battery pack, a charging input end for receiving electric energy, a discharging output end for outputting electric energy and the battery detection device according to any one of claims 1 to 9. The battery pack comprises a plurality of battery cells.

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