Energy storage device and photovoltaic energy storage system

Abstract

The invention discloses an energy storage device and a photovoltaic energy storage system. The energy storage device comprises a battery, a sampling circuit and at least one relay. The sampling circuit is configured to sample at least one parameter of current, voltage and temperature of the battery. Each relay comprises a coil assembly, a first contact and a second contact, the first contact is connected with the battery, the second contact is connected with the sampling circuit, and each relay is configured to control the first contact to be disconnected from the second contact under the condition that the value of current flowing through the coil assembly is smaller than a preset current value due to disconnection of the energy storage device and the alternating current power supply; therefore, the battery is disconnected from the sampling circuit. In the shutdown transportation and storage process, the energy storage device is disconnected from the alternating current power supply, so that the current value flowing through the coil assembly of the relay is smaller than the preset current value, the battery is disconnected from the sampling circuit, the loss of a system circuit existing in the battery is reduced, and the transportation and storage time of the energy storage device product is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage devices, and more specifically, to an energy storage device and a photovoltaic energy storage system. Background Art

[0002] During the shutdown, transportation and storage process, the battery of the energy storage device is not completely disconnected from the system circuit. In addition to the battery's own self-discharge loss, there is also loss in the system circuit, which causes more battery power loss and shortens the transportation and storage time of the energy storage device. Summary of the invention

[0003] Embodiments of the present application provide an energy storage device and a photovoltaic energy storage system.

[0004] The energy storage device provided in the embodiment of the present application may include a battery, a sampling circuit and at least one relay. The sampling circuit is configured to sample at least one parameter of the current, voltage and temperature of the battery. The relay includes a coil assembly, a first contact and a second contact, the first contact is connected to the battery, the second contact is connected to the sampling circuit, and each of the relays is configured to control the first contact to disconnect from the second contact when the energy storage device is disconnected from the AC power supply, resulting in the current value flowing through the coil assembly being less than a preset current value, so as to disconnect the battery from the sampling circuit.

[0005] During the shutdown, transportation and storage process of the energy storage device in the embodiment of the present application, the energy storage device is disconnected from the AC power supply, resulting in the current value flowing through the coil assembly of the relay being less than the preset current value, so that the battery is disconnected from the sampling circuit, reducing the loss of the system circuit where the battery exists and increasing the transportation and storage time of the energy storage device product.

[0006] In some embodiments, the battery includes a plurality of cells, the sampling circuit includes a plurality of sampling connection terminals, and when the sampling connection terminals are connected to the cells, the sampling circuit is configured to sample at least one parameter of the current, voltage, and temperature of the cells. Each of the relays includes a plurality of first contacts and a plurality of second contacts corresponding to the plurality of first contacts, each of the cells is connected to the corresponding first contact, and each of the sampling connection terminals is connected to the corresponding second contact.

[0007] In some embodiments, each of the relays further includes a plurality of third contacts corresponding to the plurality of first contacts, and when the current value flowing through the coil assembly is less than the preset current value, each of the first contacts is disconnected from the corresponding second contact and connected to the corresponding third contact. When the current value flowing through the coil assembly is greater than or equal to the preset current value, each of the first contacts is connected to the corresponding second contact and disconnected from the corresponding third contact.

[0008] In some embodiments, the energy storage device further includes an AC connector to allow the coil assembly to be connected to the AC power source through the AC connector. When the voltage value of the AC power source does not reach the preset voltage value, the current value flowing through the coil assembly is less than the preset current value, each of the first contacts is disconnected from the corresponding second contact and connected to the corresponding third contact; when the voltage value of the AC power source reaches the preset voltage value, the current value flowing through the coil assembly is greater than or equal to the preset current value, each of the first contacts is disconnected from the corresponding third contact and connected to the corresponding second contact.

[0009] In some embodiments, the preset voltage value is substantially consistent with an AC voltage value connected to the power grid.

[0010] In some embodiments, the energy storage device further includes a DC connector, a power unit, and an inverter. The DC connector is configured to access the DC voltage generated by the photovoltaic module. The power unit is connected to the DC connector and is configured to transform the DC voltage generated by the photovoltaic module and output the transformed voltage. The inverter is connected between the power unit and the AC connector, and the inverter is configured to convert the voltage output by the power unit into an AC voltage and access the AC power supply through the AC connector.

[0011] In some embodiments, the power unit is connected between the DC connector and the battery, and the power unit is further configured to provide the transformed voltage to the battery to charge the battery.

[0012] In some embodiments, the energy storage device further includes a control unit. The control unit is connected to the sampling circuit and the power unit and is configured to control the electronic devices in the power unit according to the parameters sampled by the sampling circuit, so as to control the power unit to output voltage to the battery or to output voltage to the inverter.

[0013] In some embodiments, the energy storage device further includes an auxiliary power supply. The auxiliary power supply is configured to provide an operating voltage to the control unit, the power unit and the inverter, and the voltage of the auxiliary power supply is derived from the DC voltage connected to the DC connector, the DC voltage connected to the inverter or the voltage of the battery.

[0014] In some embodiments, the control unit is also connected to the inverter, and the control unit is further configured to control the electronic devices in the inverter according to the parameters sampled by the sampling circuit to control the voltage output by the inverter to the AC connector.

[0015] In some embodiments, the energy storage device further comprises a power switch unit. The power switch unit is configured to control the auxiliary power supply to provide a working voltage to the control unit, the power unit and the inverter when triggered. When the inverter is connected to the AC power supply through the AC connector and the power switch unit is triggered, the energy storage device is turned on.

[0016] The embodiments of the present application also provide a photovoltaic energy storage system, which includes the energy storage device and photovoltaic components of the above embodiments.

[0017] The embodiment of the present application provides an energy storage device and a photovoltaic energy storage system, wherein the energy storage device may include a battery, a sampling circuit and at least one relay. The sampling circuit is configured to sample at least one parameter of the current, voltage and temperature of the battery. The relay includes a coil assembly, a first contact and a second contact, wherein the first contact is connected to the battery, and the second contact is connected to the sampling circuit, and each of the relays is configured to control the first contact to disconnect from the second contact when the energy storage device is disconnected from the AC power supply, resulting in the current value flowing through the coil assembly being less than a preset current value, so as to disconnect the battery from the sampling circuit.

[0018] During the shutdown, transportation and storage process of the energy storage device in the embodiment of the present application, the energy storage device is disconnected from the AC power supply, resulting in the current value flowing through the coil assembly of the relay being less than the preset current value, so that the battery is disconnected from the sampling circuit, reducing the loss of the system circuit where the battery exists and increasing the transportation and storage time of the energy storage device product.

[0019] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 is a schematic diagram of an energy storage device according to an embodiment of the present application;

[0022] Figure 2 is a schematic diagram of an energy storage device according to certain embodiments of the present application;

[0023] Figure 3 is a schematic diagram of an energy storage device according to certain embodiments of the present application;

[0024] Figure 4 is a schematic diagram of an energy storage device according to certain embodiments of the present application;

[0025] Figure 5 is a schematic diagram of an energy storage device according to certain embodiments of the present application;

[0026] Figure 6 is a schematic diagram of an energy storage device according to certain embodiments of the present application;

[0027] Figure 7 is a schematic diagram of an energy storage device according to certain embodiments of the present application;

[0028] Figure 8 It is a schematic diagram of a photovoltaic energy storage system according to an embodiment of the present application.

[0029] Description of main component symbols:

[0030] Energy storage device 100, AC power supply 200, battery 10, battery cell 11, sampling circuit 20, sampling connection terminal 21, relay 30, coil assembly 31, first contact 32, second contact 33, third contact 34, fourth contact 35, fifth contact 36, AC connector 41, DC connector 42, power unit 50, inverter 60, control unit 70, auxiliary power supply 81, power switch unit 82, photovoltaic energy storage system 1000, photovoltaic module 300. DETAILED DESCRIPTION

[0031] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are optional and are only used to explain the embodiments of the present application, and cannot be understood as limiting the embodiments of the present application.

[0032] During the shutdown, transportation and storage process, the battery of the energy storage device is not completely disconnected from the system circuit. In addition to the battery's own self-discharge loss, there is also loss in the system circuit, which causes more battery power loss and shortens the transportation and storage time of the energy storage device.

[0033] In the related art, the system circuit includes a sampling circuit of the battery. In order to sample the parameters of the battery, the analog front end (AFE) of the sampling circuit is usually directly connected to the positive and negative electrodes of the battery (that is, the AFE is powered by the battery). Therefore, when the battery energy storage device is shut down for transportation and storage, the AFE is equivalent to the load of the battery and keeps consuming its energy, resulting in a reduction in the transportation and storage time of the battery.

[0034] In order to solve the above technical problems, the present application provides an energy storage device (such as Figures 1 to 8 shown),

[0035] Reference Figure 1 to Figure 3 The energy storage device 100 provided in the embodiment of the present application may include a battery 10, a sampling circuit 20 and at least one relay 30. The sampling circuit 20 is configured to sample at least one parameter of the current, voltage and temperature of the battery 10. The relay 30 includes a coil assembly 31, a first contact 32 and a second contact 33, the first contact 32 is connected to the battery 10, and the second contact 33 is connected to the sampling circuit 20. Each relay 30 is configured to control the first contact 32 to disconnect from the second contact 33 when the energy storage device 100 is disconnected from the AC power source 200, resulting in a current value flowing through the coil assembly 31 being less than a preset current value, so as to disconnect the battery 10 from the sampling circuit 20.

[0036] During the shutdown, transportation and warehousing process of the energy storage device 100 according to the embodiment of the present application, since the energy storage device 100 is disconnected from the AC power supply 200, the current value flowing through the coil assembly 31 of the relay 30 is less than the preset current value, so that the battery 10 is disconnected from the sampling circuit 20, thereby reducing the loss of the system circuit of the battery 10 and improving the transportation and storage time of the energy storage device 100 product.

[0037] Specifically, the sampling circuit 20 may be a sampling circuit 20 in the management system of the battery 10 in the energy storage device 100. When the energy storage device 100 is turned on, the sampling circuit 20 is connected to the battery 10, and the sampling circuit 20 may monitor the voltage, current, temperature and other parameters of the battery 10 in real time to ensure the safety and performance of the battery 10. The sampling circuit 20 may be connected to the positive and negative electrodes of the battery 10, and obtain the terminal voltages of the positive and negative electrodes of the battery 10 to implement voltage sampling of the battery 10. The sampling circuit 20 may be provided with a sampling resistor or a current sensor, and the shunt resistor and the current sensor may be connected in series in the power supply circuit of the battery 10, and the current flowing through the power supply circuit of the battery 10 may be determined according to the voltage of the sampling resistor or the measured value of the current sensor, so as to implement current sampling of the battery 10. The sampling circuit 20 may also be provided with a temperature sensor or a thermistor, and the temperature parameter of the battery 10 may be determined according to the resistance value of the thermistor and the measured value of the temperature sensor.

[0038] The sampling circuit 20 may include an analog front end (AFE). When the energy storage device 100 is turned on, the AFE is connected to the battery 10 so that the AFE can sample the analog signal provided by the battery 10 so that the sampling circuit 20 can monitor the parameters of the battery 10 such as voltage, current and temperature in real time.

[0039] The number of relays 30 can be set to one (such as Figure 1 As shown), it can also be set to multiple (such as Figure 2 As shown in FIG. 1 , when the energy storage device 100 is connected to the AC power source 200, each relay 30 can be connected to the AC power source 200. When the energy storage device 100 is disconnected from the AC power source 200, each relay 30 is disconnected from the AC power source 200.

[0040] Reference Figure 3 , the first contact 32 is connected to the battery 10, and the second contact 33 is connected to the sampling circuit 20. When the first contact 32 is connected to the second contact 33, the sampling circuit 20 is connected to the battery 10. When the first contact 32 is disconnected from the second contact 33, the sampling circuit 20 is disconnected from the battery 10.

[0041] In some embodiments, the AC power source 200 connected to the energy storage device 100 may be an AC power source 200 provided by a power grid. Figure 3 For example, the ACL may be a live wire of an AC power line, and the ACN may be a neutral wire of the AC power line.

[0042] When the energy storage device 100 is connected to the AC power supply 200, the coil assembly 31 of each relay 30 can be connected to the AC power supply 200, and the AC power supply 200 can energize the coil assembly 31. The current value flowing through the coil assembly 31 rises to a value higher than the preset current value. At this time, the coil assembly 31 can generate a magnetic field around it based on the electromagnetic induction effect, so that the first contact 32 is connected to the second contact 33, so as to realize the connection between the sampling circuit 20 and the battery 10. Therefore, when the energy storage device 100 is connected to the AC power supply 200, the sampling circuit 20 is connected to the battery 10, and the sampling circuit 20 can detect the battery 10 in real time.

[0043] When the energy storage device 100 is disconnected from the AC power source 200, the coil assembly 31 of each relay 30 is disconnected from the AC power source 200, and the AC power source 200 no longer energizes the coil assembly 31. The current value flowing through the coil assembly 31 drops to a value lower than the preset current value, and the magnetic field generated by the coil assembly 31 based on the electromagnetic induction effect weakens, so that the first contact 32 is disconnected from the second contact 33, so that the sampling circuit 20 is disconnected from the battery 10. Therefore, when the energy storage device 100 is disconnected from the AC power source 200, the sampling circuit 20 is disconnected from the battery 10.

[0044] In this way, when the energy storage device 100 is shut down for transportation and storage, the energy storage device 100 is disconnected from the AC power supply 200, resulting in a current value flowing through the coil assembly 31 of the relay 30 being less than a preset current value, so that the battery 10 is disconnected from the sampling circuit 20, thereby reducing the loss of the system circuit where the battery 10 exists and increasing the transportation and storage time of the energy storage device 100 product.

[0045] Reference Figure 4 In some embodiments, the battery 10 includes a plurality of cells 11, and the sampling circuit 20 includes a plurality of sampling connection terminals 21. When the sampling connection terminals 21 are connected to the cells 11, the sampling circuit 20 is configured to sample at least one parameter of the current, voltage, and temperature of the cells 11. Each relay 30 includes a plurality of first contacts 32 and a plurality of second contacts 33 corresponding to the plurality of first contacts 32. Each cell 11 is connected to a corresponding first contact 32, and each sampling connection terminal 21 is connected to a corresponding second contact 33.

[0046] Specifically, each relay 30 may include a plurality of first contacts 32 and a plurality of second contacts 33, and each first contact 32 is provided with a corresponding second contact 33. According to the current flowing through the coil assembly 31, the relay 30 may control each first contact 32 to be connected or disconnected with the corresponding second contact 33.

[0047] The battery 10 may include a plurality of battery cells 11, each of which may be connected to a corresponding first contact 32. The sampling circuit 20 may include a plurality of sampling connection terminals 21, each of which may be connected to a corresponding second contact 33. The relay 30 controls each first contact 32 to be connected or disconnected with the corresponding second contact 33, so as to achieve connection or disconnection between each battery cell 11 and the corresponding sampling connection terminal 21.

[0048] When the energy storage device 100 is connected to the AC power supply 200 , each first contact 32 can be connected to the corresponding second contact 33 , so that each battery cell 11 is connected to the corresponding sampling connection terminal 21 , and the sampling circuit 20 can sample any battery cell 11 in the battery 10 through the sampling connection terminal 21 .

[0049] When the energy storage device 100 is disconnected from the AC power source 200 , each first contact 32 is disconnected from the corresponding second contact 33 , so that each battery cell 11 is disconnected from the corresponding sampling connection terminal 21 to reduce the power consumption of the battery 10 .

[0050] Reference Figure 4 The plurality of sampling connection terminals 21 of the sampling circuit 20 may include terminals C0 to C12. The plurality of cells 11 of the battery 10 may include cells B1 to B12.

[0051] The positive electrode of the battery cell B1 can be connected to the first contact 32, the second contact 33 corresponding to the first contact 32 can be connected to the C0 terminal, and the negative electrode of the battery cell B0 can be connected to the C1 terminal. The positive electrode of the battery cell B1 can be connected or disconnected from the C0 terminal. When the energy storage device 100 is connected to the AC power supply 200, the positive electrode of the battery cell B1 is connected to the C0 terminal, and the sampling circuit 20 can sample the battery cell B1. When the energy storage device 100 is disconnected from the AC power supply 200, the battery cell 11 is disconnected from the C0 terminal, and the battery cell B1 is disconnected from the sampling circuit 20.

[0052] Based on the implementation method of connecting or disconnecting the positive electrode of battery cell B1 with the C0 terminal, the relay 30 can also control the connection or disconnection of the negative electrode of battery cell B2 with the C2 terminal, the connection or disconnection of the positive electrode of battery cell B3 with the C2 terminal, the connection or disconnection of the negative electrode of battery cell B4 with the C4 terminal, the connection or disconnection of the positive electrode of battery cell B5 with the C4 terminal, the connection or disconnection of the negative electrode of battery cell B6 with the C6 terminal, the connection or disconnection of the positive electrode of battery cell B7 with the C6 terminal, the connection or disconnection of the negative electrode of battery cell B8 with the C8 terminal, the connection or disconnection of the positive electrode of battery cell B9 with the C8 terminal, the connection or disconnection of the negative electrode of battery cell B10 with the C10 terminal, the connection or disconnection of the positive electrode of battery cell B11 with the C10 terminal, and the connection or disconnection of the negative electrode of battery cell B12 with the C12 terminal.

[0053] In some embodiments, the connection or disconnection between the positive electrode of cell B1 and the C0 terminal, the connection or disconnection between the negative electrode of cell B2 and the C2 terminal, the connection or disconnection between the positive electrode of cell B3 and the C2 terminal, the connection or disconnection between the negative electrode of cell B4 and the C4 terminal, and the connection or disconnection between the positive electrode of cell B5 and the C4 terminal can be achieved by three first contacts 32 and corresponding three second contacts 33 in a relay 30.

[0054] In some embodiments, the negative electrode of battery cell B6 is connected or disconnected with the C6 terminal, the positive electrode of battery cell B7 is connected or disconnected with the C6 terminal, the negative electrode of battery cell B8 is connected or disconnected with the C8 terminal, the positive electrode of battery cell B9 is connected or disconnected with the C8 terminal, the negative electrode of battery cell B10 is connected or disconnected with the C10 terminal, the positive electrode of battery cell B11 is connected or disconnected with the C10 terminal, and the negative electrode of battery cell B12 is connected or disconnected with the C12 terminal, which can be achieved by four first contacts 32 and corresponding four second contacts 33 in a relay 30.

[0055] Reference Figure 5 In some embodiments, each relay 30 further includes a plurality of third contacts 34 corresponding to the plurality of first contacts 32. When the current value flowing through the coil assembly 31 is less than a preset current value, each first contact 32 is disconnected from the corresponding second contact 33 and connected to the corresponding third contact 34. When the current value flowing through the coil assembly 31 is greater than or equal to the preset current value, each first contact 32 is connected to the corresponding second contact 33 and disconnected from the corresponding third contact 34.

[0056] Specifically, each relay 30 may include a plurality of third contacts 34, and each first contact 32 is correspondingly provided with a third contact 34. The first contact 32 may be selectively connected to the second contact 33 or the third contact 34.

[0057] When the energy storage device 100 is connected to the AC power supply 200, the coil assembly 31 of each relay 30 can be connected to the AC power supply 200, the AC power supply 200 can energize the coil assembly 31, and the current value flowing through the coil assembly 31 rises to a value higher than the preset current value, and the first contact 32 is connected to the second contact 33 and disconnected from the third contact 34.

[0058] When the energy storage device 100 is disconnected from the AC power supply 200, the coil assembly 31 of each relay 30 is disconnected from the AC power supply 200, the AC power supply 200 no longer energizes the coil assembly 31, the current value flowing through the coil assembly 31 drops to a value lower than the preset current value, and the first contact 32 is disconnected from the second contact 33 and disconnected from the third contact 34.

[0059] In some embodiments, the relay 30 may also include a fourth contact 35 and a fifth contact 36, the fourth contact 35 is connected to one end of the coil assembly 31, and the fifth contact 36 is connected to the other end of the coil assembly 31, and the fourth contact 35 and the fifth contact 36 can be connected to the AC power supply 200.

[0060] When the energy storage device 100 is connected to the AC power source 200, the fourth contact 35 and the fifth contact 36 can be connected to the AC power source 200. When the energy storage device 100 is disconnected from the AC power source 200, the fourth contact 35 and the fifth contact 36 are disconnected from the AC power source 200.

[0061] In some embodiments, a relay 30 may include multiple first contacts 32 and multiple second contacts 33 and third contacts 34 corresponding to the first contacts 32 , and each first contact 32 may select to connect to the second contact 33 or the third contact 34 controlled by the current value flowing through the same coil assembly 31 .

[0062] Reference Figure 4 In some embodiments, the energy storage device 100 further includes an AC connector 41 to allow the coil assembly 31 to be connected to the AC power source 200 through the AC connector 41. When the voltage value of the AC power source 200 does not reach the preset voltage value, the current value flowing through the coil assembly 31 is less than the preset current value, each first contact 32 is disconnected from the corresponding second contact 33 and connected to the corresponding third contact 34. When the voltage value of the AC power source 200 reaches the preset voltage value, the current value flowing through the coil assembly 31 is greater than or equal to the preset current value, each first contact 32 is disconnected from the corresponding third contact 34 and connected to the corresponding second contact 33.

[0063] Specifically, the coil assembly 31 can be connected in parallel between the two ends of the AC connector 41. When the voltage value of the AC power supply 200 connected to the energy storage device 100 is small, and when the voltage value of the AC power supply 200 does not reach the preset voltage value, the current generated by the AC power supply 200 energizing the coil assembly 31 is small, and the current value flowing through the coil assembly 31 is less than the preset current value, and the battery 10 is disconnected from the sampling circuit 20.

[0064] When the voltage value of the AC power supply 200 connected to the energy storage device 100 is large enough, and when the voltage value of the AC power supply 200 reaches a preset voltage value, the current generated by the AC power supply 200 energizing the coil component 31 is large enough, and the current value flowing through the coil component 31 is greater than or equal to the preset current value, the battery 10 is connected to the sampling circuit 20.

[0065] In this way, it can be avoided that when the energy storage device 100 is connected to the AC power source 200 with a relatively low voltage, the battery 10 is connected to the sampling circuit 20 to consume the power of the battery 10 .

[0066] In some implementations, the preset voltage value is substantially consistent with the AC voltage value of the grid access.

[0067] Specifically, the AC power source 200 connected to the energy storage device 100 may be an AC power source 200 provided by a power grid. Figure 3 For example, ACL can be the live wire of the AC power line, and ACN can be the neutral wire of the AC power line. The preset voltage value can be set to 220V AC voltage or 230V AC voltage, so that the energy storage device 100 is compatible with the mains.

[0068] Reference Figure 6 In some embodiments, the energy storage device 100 further includes a DC connector 42, a power unit 50, and an inverter 60. The DC connector 42 is configured to access the DC voltage generated by the photovoltaic module 300. The power unit 50 is connected to the DC connector 42, and is configured to transform the DC voltage generated by the photovoltaic module 300 and output the transformed voltage. The inverter 60 is connected between the power unit 50 and the AC connector 41, and the inverter 60 is configured to convert the voltage output by the power unit 50 into an AC voltage and connect it to the AC power source 200 through the AC connector 41.

[0069] Specifically, the DC connector 42 of the energy storage device 100 can be connected to the photovoltaic assembly 300 to achieve the function of photovoltaic power generation. The DC connector 42 may include a PV1+ terminal, a PV1- terminal, a PV2+ terminal, and a PV2- terminal. Among them, the PV1+ terminal and the PV1- terminal can be connected to the positive and negative poles of one photovoltaic assembly 300, and the PV2+ terminal and the PV2- terminal can be connected to the positive and negative poles of another photovoltaic assembly 300.

[0070] The power unit 50 can realize power conversion, converting the DC voltage connected to the DC connector 42 into a corresponding AC voltage for the DC side of the inverter 60 .

[0071] The inverter 60 can control the internal electronic switching devices (such as Figure 6 The Q1a-Q5a and Q1b-Q5b) shown in the figure convert the DC voltage connected to the DC side (such as the DC bus) into AC voltage and provide it to the AC power supply 200.

[0072] Reference Figure 7 In some embodiments, the power unit 50 is connected between the DC connector 42 and the battery 10 , and the power unit 50 is further configured to provide the transformed voltage to the battery 10 to charge the battery 10 .

[0073] Specifically, the power unit 50 can realize power conversion, and convert the DC voltage connected to the DC connector 42 into a corresponding DC voltage and provide it to the battery 10 through the charging circuit, so as to realize charging of the battery 10 .

[0074] Reference Figure 7 In some embodiments, the energy storage device 100 further includes a control unit 70. The control unit 70 is connected to the sampling circuit 20 and the power unit 50, and is configured to control the electronic devices in the power unit 50 according to the parameters sampled by the sampling circuit 20, so as to control the power unit 50 to output voltage to the battery 10 or to output voltage to the inverter 60.

[0075] Specifically, the control unit 70 may be a control unit 70 of a battery 10 management system in the energy storage device 100 . The control unit 70 may control the electronic devices in the power unit 50 according to the parameters sampled by the sampling circuit 20 , so as to control the output voltage of the power unit 50 to the inverter 60 and the output voltage to the battery 10 .

[0076] The control unit 70 may include a digital signal processing module (DSP control unit) and a single-chip microcomputer module (MCU control unit). The single-chip microcomputer module is connected to the sampling circuit 20, and controls the connection or disconnection between the battery 10 and the power unit 50 according to the parameters sampled by the sampling circuit 20, or controls the output impedance of the power unit 50 to the battery 10, so as to control the voltage output by the power unit 50 to the battery 10.

[0077] The digital signal processing module can be connected to the single-chip microcomputer module for communication. The digital signal processing module receives data sent from the single-chip microcomputer module and processes the data. The digital signal processing module can also send the processed data to the single-chip microcomputer module. The digital signal processing module can control the electronic devices in the power unit 50 to control the output voltage of the power unit 50 to the inverter 60 and the battery 10.

[0078] The control unit 70 may further include a remote communication module, and the single chip computer module and the digital signal processing module may further control the output voltage of the power unit 50 according to information received by the remote communication module.

[0079] In some embodiments, the control unit 70 is also connected to the inverter 60 , and the control unit 70 is further configured to control the electronic components in the inverter 60 according to the parameters sampled by the sampling circuit 20 to control the voltage output by the inverter 60 to the AC connector 41 .

[0080] Specifically, the single chip microcomputer module is connected to the sampling circuit 20, and controls the electronic switch devices (such as Figure 6Q1a-Q5a and Q1b-Q5b) are turned on or off to control the output voltage of the inverter 60.

[0081] The single-chip microcomputer module can also control the electronic switch devices (such as Figure 6 Q1a-Q5a and Q1b-Q5b) are turned on or off to control the output voltage of the inverter 60.

[0082] In some embodiments, the energy storage device 100 further includes an auxiliary power supply 81. The auxiliary power supply 81 is configured to provide an operating voltage to the control unit 70, the power unit 50 and the inverter 60, and the voltage of the auxiliary power supply 81 is derived from the DC voltage connected to the DC connector 42, the DC voltage connected to the inverter 60 or the voltage of the battery 10.

[0083] Specifically, when the auxiliary power supply 81 is turned off, the control unit 70, the power unit 50 and the inverter 60 stop working. When the auxiliary power supply 81 is turned on, the control unit 70, the power unit 50 and the inverter 60 start working.

[0084] The auxiliary power supply 81 can be connected to the DC voltage provided by the photovoltaic component 300 through the PV1+ terminal and the PV2+ terminal. The auxiliary power supply 81 can be connected to the DC bus of the inverter 60 through the Vbus terminal to access the voltage on the DC side of the inverter 60. The auxiliary power supply 81 can also be connected to the positive pole of the battery 10 through the B+ terminal and access the voltage of the battery 10.

[0085] Reference Figure 7 In some embodiments, the energy storage device 100 further includes a power switch unit 82. The power switch unit 82 is configured to control the auxiliary power supply 81 to provide a working voltage to the control unit 70, the power unit 50 and the inverter 60 when triggered. When the inverter 60 is connected to the AC power supply 200 through the AC connector 41 and the power switch unit 82 is triggered, the energy storage device 100 is turned on.

[0086] Specifically, the power switch unit 82 is configured to, when triggered, turn on the energy storage device 100, turn on the auxiliary power supply 81, and start the control unit 70, the power unit 50, and the inverter 60. When not triggered, the power switch unit 82 is configured to, when not triggered, turn off the energy storage device 100, turn off the auxiliary power supply 81, and stop the control unit 70, the power unit 50, and the inverter 60.

[0087] In some embodiments, the energy storage device 100 may further include a button display unit, which may display whether a control button of the power switch unit 82 is triggered.

[0088] Reference Figure 8 The embodiment of the present application further provides a photovoltaic energy storage system 1000, which includes the energy storage device 100 and the photovoltaic assembly 300 of the above embodiment. The photovoltaic energy storage system 1000 can include all the technical effects of the energy storage device 100 of the above embodiment, which will not be described one by one here.

[0089] The energy storage device 100 provided in the embodiment of the present application does not require the provision of complex electronic circuits and software control methods, and is applicable to various unidirectional single-phase pluggable power generation equipment.

[0090] The energy storage device 100 provided in the embodiment of the present application uses the output characteristics of the inverter 60 in combination with the relay 30 to automatically disconnect the connection line between the battery 10 and the sampling circuit 20 during the transportation and storage state of the energy storage device 100, thereby reducing the loss of the battery 10 and improving the transportation and storage time of the energy storage device 100. When the energy storage device 100 is connected to the AC power supply 200, the relay 30 can automatically connect the connection line between the battery 10 and the sampling circuit 20.

[0091] The energy storage device 100 provided in the embodiment of the present application does not need to set up additional software or hardware to specifically detect the voltage value, SOC value or energy value of the battery 10 to control the disconnection and connection of the relay 30. The hardware circuit is simple and universal, with low cost and high adaptability and versatility.

[0092] In the energy storage device 100 provided in the embodiment of the present application, the relay 30 can be used as a separate module, which does not affect the original software control program, BMS control strategy, sampling circuit 20, inverter 60 and other designs in the energy storage device 100, and has high applicability and compatibility. Of course, the relay 30 can also be integrated into the power unit 50 or the inverter 60, so that the energy storage device 100 has the advantage of integration.

[0093] In the description of this specification, the descriptions with reference to the terms "certain embodiments", "in an example", "exemplarily", etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0094] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0095] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are optional and cannot be understood as limitations to the present application. A person skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. An energy storage device, characterized in that: The energy storage device comprises: Battery; A sampling circuit configured to sample at least one parameter of a current, a voltage and a temperature of a battery; At least one relay, each of the relays comprises a coil assembly, a first contact and a second contact, the first contact is connected to the battery, and the second contact is connected to the sampling circuit, and each of the relays is configured to control the first contact to be disconnected from the second contact when the energy storage device is disconnected from the AC power supply, resulting in a current value flowing through the coil assembly being less than a preset current value, so as to disconnect the battery from the sampling circuit.

2. The energy storage device according to claim 1, characterized in that: The battery comprises a plurality of cells, the sampling circuit comprises a plurality of sampling connection terminals, and when the sampling connection terminals are connected to the cells, the sampling circuit is configured to sample at least one parameter of the current, voltage and temperature of the cells; Each of the relays includes a plurality of first contacts and a plurality of second contacts corresponding to the plurality of first contacts, each of the battery cells is connected to a corresponding first contact, and each of the sampling connection terminals is connected to a corresponding second contact.

3. The energy storage device according to claim 2, characterized in that: Each of the relays further includes a plurality of third contacts corresponding to the plurality of first contacts, and when the current value flowing through the coil assembly is less than the preset current value, each of the first contacts is disconnected from the corresponding second contact and connected to the corresponding third contact; When the current value flowing through the coil assembly is greater than or equal to the preset current value, each of the first contacts is connected to the corresponding second contact and disconnected from the corresponding third contact.

4. The energy storage device according to claim 3, characterized in that: The energy storage device further comprises an AC connector to allow the coil assembly to be connected to the AC power source through the AC connector; When the voltage value of the AC power supply does not reach the preset voltage value, the current value flowing through the coil assembly is less than the preset current value, each of the first contacts is disconnected from the corresponding second contact and connected to the corresponding third contact. When the voltage value of the AC power supply reaches the preset voltage value, the current value flowing through the coil assembly is greater than or equal to the preset current value, each of the first contacts is disconnected from the corresponding third contact and connected to the corresponding second contact.

5. The energy storage device according to claim 4, characterized in that: The preset voltage value is substantially consistent with the AC voltage value of the power grid.

6. The energy storage device according to claim 1, characterized in that: The energy storage device also includes: A DC connector configured to access a DC voltage generated by the photovoltaic module; an AC connector configured to be connected to the AC power source; a power unit connected to the DC connector and configured to transform the DC voltage generated by the photovoltaic module and output the transformed voltage; An inverter is connected between the power unit and the AC connector, and is configured to convert the voltage output by the power unit into an AC voltage and connect the AC voltage to the AC power source through the AC connector.

7. The energy storage device according to claim 6, characterized in that: The power unit is connected between the DC connector and the battery, and is further configured to provide the transformed voltage to the battery to charge the battery.

8. The energy storage device according to claim 7, characterized in that: The energy storage device also includes: A control unit is connected to the sampling circuit and the power unit, and is configured to control the electronic devices in the power unit according to the parameters sampled by the sampling circuit, so as to control the power unit to output voltage to the battery or to output voltage to the inverter.

9. The energy storage device according to claim 8, characterized in that: The control unit is also connected to the inverter, and is further configured to control the electronic components in the inverter according to the parameters sampled by the sampling circuit, so as to control the voltage output by the inverter to the AC connector.

10. The energy storage device according to claim 8, characterized in that: The energy storage device also includes: An auxiliary power supply is configured to provide an operating voltage to the control unit, the power unit and the inverter, and the voltage of the auxiliary power supply is derived from the DC voltage connected to the DC connector, the DC voltage connected to the inverter or the voltage of the battery.

11. The energy storage device according to claim 10, characterized in that: The energy storage device also includes: a power switch unit, configured to control the auxiliary power supply to provide a working voltage to the control unit, the power unit and the inverter when triggered; When the inverter is connected to the AC power source through the AC connector and the power switch unit is triggered, the energy storage device is turned on.

12. A photovoltaic energy storage system, characterized in that: The photovoltaic energy storage system comprises the energy storage device and photovoltaic assembly described in any one of claims 1-11.

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