Energy storage battery and control method therefor

Abstract

An energy storage battery and a control method therefor. The energy storage battery comprises a plurality of battery packs connected in parallel, each battery pack comprising a plurality of batteries connected in series, wherein each battery comprises a charging-discharging circuit. Each charging-discharging circuit comprises a storage battery, a first switch and a second switch, the first switch and the second switch being used for controlling the on-off of a connection line between two batteries. The plurality of batteries are connected in series to form a battery pack, and the plurality of battery packs are connected in parallel to form the energy storage battery, such that when the energy storage battery operates, each battery independently controls the on-off of its first switch and second switch, so as to control the on-off of the connection lines between the battery and other batteries, thereby allowing each battery of the energy storage battery to be freely extended. When a certain battery has a fault, it is merely required to control the battery pack where the battery is located and to disconnect and repair the faulty battery, thus improving the overall operation efficiency of the energy storage battery.

Description

Energy storage battery and control method thereof

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on August 10, 2023, with application number 202311005064.6 and entitled “A Storage Battery and Its Control Method,” the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the field of power distribution technology, and in particular to an energy storage battery and a control method thereof. Background Art

[0003] Electrochemical energy storage has experienced rapid growth in recent years, with increasing market demand. Short-term power outages caused by energy storage system failures can severely impact both user experience and economic benefits. Therefore, when designing an energy storage system, fault tolerance and scalability must be fully considered at every stage. Commercially available energy storage systems typically consist of an inverter and energy storage batteries, which are composed of a battery management system and multiple cells.

[0004] The existing energy storage battery is a single integral battery and is not expandable. When you want to expand the capacity or increase the voltage platform, you must replace the entire energy storage battery. In addition, the single integral energy storage battery has a low fault tolerance rate. When a component or battery cell in the energy storage battery fails, the entire system needs to stop working and the entire energy storage battery needs to be repaired or even scrapped. The system operation efficiency is low and the maintenance cost is high.

[0005] Summary of the Invention

[0006] The present invention provides an energy storage battery and a control method thereof, so as to solve the technical problems of low fault tolerance and high maintenance cost of energy storage batteries in existing energy storage systems.

[0007] In order to solve the above technical problems, an embodiment of the present invention provides an energy storage battery, comprising a plurality of battery packs connected in parallel, and each of the battery packs comprises a plurality of batteries connected in series;

[0008] The battery includes a charge and discharge circuit; the charge and discharge circuit includes a storage battery, a first switch and a second switch; the first switch and the second switch are used to control the opening or closing of the connection line between the two batteries.

[0009] The present invention connects several batteries in series to form a battery pack, and simultaneously connects several battery packs in parallel to form an energy storage battery. During operation of the energy storage battery, each battery independently controls the opening and closing of its own first switch and second switch, thereby controlling the connection or closing of each battery's connection circuit with the remaining batteries. This allows for free expansion of individual batteries in the energy storage battery, and removing or adding batteries will not affect the operation of batteries in other battery packs in the energy storage battery. When a battery fails, only the battery pack in which it is located needs to be controlled to power off and repair the faulty battery, without stopping the operation of the entire energy storage battery. This improves the overall operating efficiency and fault tolerance of the energy storage battery.

[0010] Furthermore, the battery includes a positive terminal and a negative terminal. In the charge and discharge circuit, the positive terminal of the battery is connected to the positive terminal, and the negative terminal of the battery is connected to the negative terminal; the first switch is arranged between the positive terminal of the battery and the positive terminal; and the second switch is arranged between the negative terminal of the battery and the negative terminal.

[0011] Furthermore, the battery further includes a charge and discharge limiting branch, and the charge and discharge limiting branch is arranged in parallel with the first switch.

[0012] Furthermore, the limiting charge and discharge branch includes a limiting charge branch and a limiting discharge branch; the limiting charge branch and the limiting discharge branch are arranged in parallel;

[0013] The charging limiting branch includes a first diode and a fourth switch, wherein the first diode and the fourth switch are arranged in series between the positive electrode of the battery and the positive electrode terminal, and the positive electrode of the first diode is connected to the positive electrode of the battery;

[0014] The discharge limiting branch includes a second diode and a fifth switch, the second diode and the fifth switch are arranged in series between the positive electrode of the battery and the positive terminal, and the cathode of the second diode is connected to the positive electrode of the battery.

[0015] Furthermore, the battery further includes a pre-charging branch, which is arranged in parallel with the first switch.

[0016] Furthermore, the pre-charging branch includes a pre-charging resistor and a third switch, and the pre-charging resistor and the third switch are arranged in series between the positive electrode of the battery and the positive electrode terminal.

[0017] Furthermore, the energy storage battery adopts a CAN bus architecture to connect the battery packs; one battery in the battery pack is set as a master battery, and the remaining batteries are set as slave batteries.

[0018] In a second aspect, the present invention provides a balanced charge and discharge method for an energy storage battery, which is applied to the energy storage battery, comprising:

[0019] Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation;

[0020] When the battery enters the discharge mode, a balanced discharge voltage operation is performed on each battery pack according to a first voltage; and a full discharge operation is performed according to the SOC value of all batteries; the first voltage is the maximum voltage of each non-fault battery pack in the energy storage battery;

[0021] When entering the charging mode, a balanced charging voltage operation is performed on each battery pack according to a second voltage; and a full charging operation is performed according to the SOC value of all batteries; the second voltage is the minimum voltage of each fault-free battery pack in the energy storage battery.

[0022] Furthermore, performing a balanced discharge voltage operation on each battery pack according to the first voltage includes:

[0023] Determining a current first voltage of the energy storage battery, where the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery;

[0024] Screening unpowered battery packs according to the first voltage and a preset first voltage difference to determine all second battery packs that meet a power-on condition;

[0025] limiting the total charge and discharge current of the energy storage battery according to the number of currently online battery packs, and powering on the second battery pack;

[0026] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced discharge voltage operation is completed.

[0027] Furthermore, performing a balanced charging voltage operation on each battery pack according to the second voltage includes:

[0028] Determining a current second voltage of the energy storage battery, where the second voltage is a minimum voltage of each non-faulty battery group in the energy storage battery;

[0029] Screening unpowered battery packs according to the second voltage and a preset second voltage difference to determine all third battery packs that meet a power-on condition;

[0030] Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery packs, and powering on the second battery pack;

[0031] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced charging voltage operation is completed.

[0032] In a third aspect, the present invention provides a method for eliminating energy storage battery faults, which is applied to the energy storage battery, comprising:

[0033] Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation;

[0034] After entering the discharge mode or the charge mode, when a faulty battery pack is detected, a current limiting instruction is sent to the battery packs other than the faulty battery pack according to the number of powered-on battery packs and the first current threshold to limit the total charge and discharge current;

[0035] A power-off instruction is sent to the faulty battery pack, and after the faulty battery pack is powered off, a current limiting release instruction is sent to each powered-on battery pack; wherein the faulty battery pack is a powered-on battery pack with a serious battery failure.

[0036] In a fourth aspect, the present invention provides a method for charging and discharging an energy storage battery without switching, which is applied to the energy storage battery, comprising:

[0037] Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation;

[0038] The inductive switching operation includes: when detecting that there is a first battery pack that is in a powered-on state but does not meet the power-on conditions, sending a control instruction to the first battery; the first battery is the first battery in the first battery pack; the first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, wherein the switching operation includes discharging to charging and charging to discharging.

[0039] Furthermore, the first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, including:

[0040] When the switching operation is discharging to charging, closing the fifth switch of the first battery to connect to the limited discharge branch provided with the second diode, and opening the first switch;

[0041] When the switching operation is from charge to discharge, the fourth switch of the first battery is closed to connect to the limiting charging branch provided with the first diode, and the first switch is opened.

[0042] Furthermore, after the sensorless switching operation, a second power-on operation is also included, and the second power-on operation includes:

[0043] Closing the second switch of the third battery and the fifth switch of the first battery in all battery packs that meet the power-on condition;

[0044] Closing the second switch of the third battery and the first switch of the first battery in all battery packs that do not meet the power-on condition;

[0045] The third battery is the last battery in the battery pack, and the first battery is the first battery in the battery pack.

[0046] In a fifth aspect, the present invention provides an energy storage battery control method, which is applied to the energy storage battery, comprising:

[0047] Receive a power-on instruction so that the master battery performs a first power-on operation on all batteries according to the power-on instruction, and enters a discharge mode after successful power-on; when it is detected that the energy storage battery is fully discharged, it enters a charging mode according to a senseless switching operation; when it is detected that the energy storage battery is fully charged, it enters a discharge mode according to the senseless switching operation.

[0048] Furthermore, when the battery enters the discharge mode, a balanced discharge voltage operation is performed on each battery pack according to a first voltage; and a full discharge operation is performed according to the SOC value of all batteries; the first voltage is the maximum voltage of each non-fault battery pack in the energy storage battery;

[0049] When entering the charging mode, a balanced charging voltage operation is performed on each battery pack according to a second voltage; and a full charging operation is performed according to the SOC value of all batteries; the second voltage is the minimum voltage of each fault-free battery pack in the energy storage battery.

[0050] Furthermore, performing a balanced discharge voltage operation on each battery pack according to the first voltage includes:

[0051] Determining a current first voltage of the energy storage battery, where the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery;

[0052] Screening unpowered battery packs according to the first voltage and a preset first voltage difference to determine all second battery packs that meet a power-on condition;

[0053] Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery packs, and powering on the second battery pack;

[0054] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced discharge voltage operation is completed.

[0055] Furthermore, performing a balanced charging voltage operation on each battery pack according to the second voltage includes:

[0056] Determining a current second voltage of the energy storage battery, where the second voltage is a minimum voltage of each non-faulty battery group in the energy storage battery;

[0057] Screening unpowered battery packs according to the second voltage and a preset second voltage difference to determine all third battery packs that meet a power-on condition;

[0058] Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery packs, and powering on the second battery pack;

[0059] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced charging voltage operation is completed.

[0060] Furthermore, after entering the discharge mode or the charging mode, when a faulty battery group is detected, a current limiting instruction is sent to the battery groups other than the faulty battery group based on the number of powered-on battery groups and the first current threshold to limit the total charge and discharge current; and a power-off instruction is sent to the faulty battery group until the faulty battery group is powered off, and then a current limiting release instruction is sent to each powered-on battery group; wherein, the faulty battery group is a powered-on battery group in which a serious battery fault has occurred.

[0061] Furthermore, the senseless switching operation includes:

[0062] When detecting that there is a first battery pack that is in a powered-on state but does not meet the power-on condition, sending a control instruction to the first battery; the first battery is the first battery in the first battery pack;

[0063] The first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, wherein the switching operation includes discharging to charging and charging to discharging.

[0064] Furthermore, the first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, including:

[0065] When the switching operation is discharging to charging, closing the fifth switch of the first battery to connect to the limited discharge branch provided with the second diode, and opening the first switch;

[0066] When the switching operation is from charge to discharge, the fourth switch of the first battery is closed to connect to the limiting charging branch provided with the first diode, and the first switch is opened. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] FIG1 is a schematic structural diagram of an energy storage battery provided by an embodiment of the present invention;

[0068] FIG2 is an electrical diagram of an energy storage battery provided by an embodiment of the present invention.

[0069] Among them, the figure numbers of the drawings in the specification are as follows: 1. charging and discharging circuit; 2. pre-charging branch; 3. limiting charging and discharging branch; 4. battery; 5. first switch; 6. second switch; 7. positive terminal; 8. negative terminal; 9. third switch; 10. fourth switch; 11. fifth switch; 12. first diode; 13. second diode; 14. pre-charging resistor. DETAILED DESCRIPTION

[0070] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0071] Example 1

[0072] Please refer to FIG1 , which is a schematic structural diagram of an energy storage battery provided by an embodiment of the present invention, including a plurality of battery packs connected in parallel, and each of the battery packs includes a plurality of batteries connected in series;

[0073] The battery includes a charge and discharge circuit 1; the charge and discharge circuit 1 includes a battery 4, a first switch 5 and a second switch 6; the first switch 5 and the second switch 6 are used to control the opening or closing of the connection line between the two batteries.

[0074] In this embodiment, the energy storage battery is connected to each battery pack using a CAN bus architecture; one battery in the battery pack is set as a master battery, and the remaining batteries are set as slave batteries.

[0075] In this embodiment, the energy storage battery is composed of m battery packs connected in parallel, each of which includes n cells. Within each battery pack, one cell is adaptively configured as the master cell, while the remaining cells are configured as slave cells. Configuration information sent by an external device calibrates the number of cells in the energy storage battery, i.e., m battery packs consisting of n cells are connected in parallel. Each cell is calibrated using a DIP switch on the battery, with each cell numbered from 1 to n*m-1.

[0076] In this embodiment, the external device includes an inverter and an external control device.

[0077] In this embodiment, the slave-controlled battery sends the second battery information to the master-controlled battery according to the network. The master-controlled battery collects the second battery information of all slave-controlled batteries, processes the second battery information and its own first battery information, and sends the battery information of the entire energy storage battery to the external device.

[0078] In this embodiment, the energy storage device sends the received battery information of the energy storage battery to the external control device through the inverter, and obtains the power on and off instructions of the external control device through the inverter and sends them to the main control battery.

[0079] In this embodiment, several batteries are connected in series to form a battery pack, and several battery packs are connected in parallel to form an energy storage battery. During operation of the energy storage battery, each battery independently controls the opening and closing of its own first switch 5 and second switch 6, thereby controlling the connection or closing of each battery's connection circuit with the remaining batteries. This allows for free expansion of individual batteries in the energy storage battery, and removing or adding batteries will not affect the operation of batteries in other battery packs in the energy storage battery. When a battery fails, only the battery pack in which it is located needs to be controlled to power off and repair the faulty battery, without stopping the operation of the entire energy storage battery. This improves the overall operating efficiency and fault tolerance of the energy storage battery.

[0080] Please refer to FIG. 2 , which is an electrical diagram of an energy storage battery provided by an embodiment of the present invention.

[0081] In this embodiment, the battery includes a positive terminal 7 and a negative terminal 8. In the charge and discharge circuit 1, the positive electrode of the battery 4 is connected to the positive terminal 7, and the negative electrode of the battery 4 is connected to the negative terminal 8; the first switch 5 is arranged between the positive electrode of the battery 4 and the positive terminal 7; and the second switch 6 is arranged between the negative electrode of the battery 4 and the negative terminal 8.

[0082] In this embodiment, since each battery has an independent charge and discharge circuit 1 and a battery management system, all batteries can serve as both master batteries and slave batteries. When a battery fails, it is only necessary to disconnect the battery pack and perform maintenance without stopping the operation of the entire energy storage battery. This improves the operating efficiency of the entire energy storage battery and enhances fault tolerance.

[0083] In this embodiment, by providing an independent battery management system in each battery, all batteries can be used as master batteries or slave batteries. When a single battery fails, there is no need to stop the operation of the entire energy storage battery, thereby improving the operating efficiency of the entire energy storage battery. At the same time, there is no need to return the entire energy storage battery for repair, only the current battery needs to be repaired, thereby reducing repair costs.

[0084] In this embodiment, the battery further includes a charge and discharge limiting branch 3 , and the charge and discharge limiting branch 3 is arranged in parallel with the first switch 5 .

[0085] In this embodiment, the charge and discharge limiting branch 3 includes a charge limiting branch and a discharge limiting branch; the charge limiting branch and the discharge limiting branch are arranged in parallel;

[0086] The limiting charging branch includes a first diode 12 and a fourth switch 10, wherein the first diode 12 and the fourth switch 10 are arranged in series between the positive electrode of the battery 4 and the positive electrode terminal 7, and the positive electrode of the first diode 12 is connected to the positive electrode of the battery 4;

[0087] The discharge limiting branch includes a second diode 13 and a fifth switch 11 , wherein the second diode 13 and the fifth switch 11 are arranged in series between the positive electrode of the battery 4 and the positive electrode terminal 7 , and the cathode of the second diode 13 is connected to the positive electrode of the battery 4 .

[0088] In this embodiment, a first diode 12 is provided in the limited charge branch. During the charge-to-discharge transition, the limited charge branch is connected via the fourth switch 10 to control the current flow within the battery, thereby preventing current backflow caused by an excessive voltage difference during the charge-to-discharge transition, thereby achieving a senseless switching of the battery from charge to discharge. A second diode 13 is provided in the limited charge branch. During the discharge-to-charge transition, the limited discharge branch is connected via the fifth switch 11 to control the current flow within the battery. During the discharge-to-charge transition, the limited discharge branch is connected via the fifth switch 11 to control the current flow within the battery, thereby preventing current backflow caused by an excessive voltage difference during the discharge-to-charge transition, thereby achieving a senseless switching of the battery from discharge to charge.

[0089] In this embodiment, the battery further includes a pre-charging branch 2 , and the pre-charging branch 2 is connected in parallel with the first switch 5 .

[0090] In this embodiment, the pre-charging branch 2 includes a pre-charging resistor 14 and a third switch 9 , and the pre-charging resistor 14 and the third switch 9 are arranged in series between the positive electrode of the battery 4 and the positive electrode terminal 7 .

[0091] In this embodiment, the pre-charge branch 2 is provided so that the battery can automatically control the internal current through the pre-charge branch 2. When the external input current is too large, the fifth switch 11 opens the path of the pre-charge branch 2 to charge the battery, thereby preventing damage to the battery caused by the excessive external input current. This achieves the effect of regulating the internal current of the battery.

[0092] In this embodiment, the first switch 5, the second switch 6, the third switch 9, the fourth switch 10 and the fifth switch 11 in the battery are all configured as relays, which automatically adjust the connection or closing of the circuit according to the current inside the battery, thereby achieving the effect of automatically adjusting the current inside the battery.

[0093] As a specific example of an embodiment of the present invention, the battery voltage platform is 50V, and each battery has an independent charge and discharge circuit 1 and a battery management system. The charge and discharge circuit 1 includes Rly1, Rly2, and Rly3, where Rly1 and Rly2 are the first switch 5 and the second switch 6, respectively, and Rly3 is the third switch 9. The circuit where Rly3 is located is the pre-charge circuit. The first switch 5, the second switch 6, and the third switch 9 are all configured as relays.

[0094] In this embodiment, the energy storage battery adopts a CAN bus architecture to connect each battery pack, and the battery information of the master battery in each battery pack is calibrated by the configuration information sent by the external device, and the battery information of the slave battery is calibrated by the dip switches on each battery.

[0095] In this embodiment, the entire energy storage battery adopts a CAN communication network architecture, and the battery connected to the inverter CAN in the external device is adaptively set as the master battery, and the remaining batteries are set as slave batteries.

[0096] In this embodiment, the external device and each battery in the energy storage battery are connected via a CAN bus architecture. The battery connected to the external device CAN is adaptively set as the master battery, and the remaining batteries are set as slave batteries. The slave batteries set different CAN IDs according to their own serial numbers and send secondary battery information to the master battery via the intermediate CAN network. The master battery collects the secondary battery information of all slave batteries and its own primary battery information, processes it, and sends it to the external device.

[0097] In this embodiment, the external device includes a computer, an inverter, and other devices capable of sending instructions.

[0098] An embodiment of the present invention further provides a balanced charge and discharge method for an energy storage battery, which is applied to the energy storage battery, comprising:

[0099] Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation;

[0100] When the battery enters the discharge mode, a balanced discharge voltage operation is performed on each battery pack according to a first voltage; and a full discharge operation is performed according to the SOC value of all batteries; the first voltage is the maximum voltage of each non-fault battery pack in the energy storage battery;

[0101] When entering the charging mode, a balanced charging voltage operation is performed on each battery pack according to a second voltage; and a full charging operation is performed according to the SOC value of all batteries; the second voltage is the minimum voltage of each fault-free battery pack in the energy storage battery.

[0102] In this embodiment, the energy storage battery further includes a pre-processing operation before receiving the power-on instruction. The pre-processing operation includes: the energy storage battery performs an initialization self-test. After the self-test passes, the battery pack in the energy storage battery is pre-processed in series and discharged for pre-power-on.

[0103] In this embodiment, the series pre-processing of the battery groups in the energy storage battery includes: the master control battery sends an instruction to close the second relay of the first battery of each series battery group (i.e., the 1st, n+1, 2n+1...n*m-n+1 batteries), close the first switch 5 of the last battery of each series battery group (i.e., the nth, 2nth, m*nth batteries), and close the first switch 5 and the second switch 6 of the remaining batteries.

[0104] In this embodiment, the discharge pre-power-on operation includes: screening out battery packs without battery failures in units of battery packs, calculating the total voltage of the battery packs, obtaining the highest voltage among all battery packs as the first power-on voltage, and screening out all battery packs that meet the power-on conditions based on the first power-on voltage, setting the pre-power-on instruction of the battery packs that meet the power-on conditions to 1, and setting the power-on instruction of the battery packs that do not meet the power-on conditions to 2.

[0105] As a specific example of an embodiment of the present invention, screening out all battery packs meeting the power-on condition according to the first power-on voltage includes determining a battery pack whose voltage difference with the first power-on voltage is within a default threshold as a battery pack meeting the power-on condition.

[0106] In this embodiment, each battery pack is powered on by controlling the main control battery, and by balancing the voltage of each battery, high-voltage batteries are selected to be incorporated into the energy storage system during discharge, and low-voltage batteries are selected to be incorporated into the energy storage system during charging, thereby fully releasing the battery capacity and balancing the battery voltage, thereby improving the battery charging and discharging efficiency; at the same time, the charging and discharging of the inverter is prevented from being uncontrollable through the senseless switching operation, and the battery voltage switching is completed while ensuring the stability of the voltage end.

[0107] In this embodiment, after completing the pre-processing operation, the energy storage battery receives the power-on instruction and transmits the power-on instruction to the master control battery of each battery pack to perform a first power-on operation. The first power-on operation includes: closing the second switch 6 of the last battery of all battery packs whose pre-power-on instructions are 1, closing the third switch 9 of the first battery of all battery packs whose pre-power-on instructions are 1, so that they enter the pre-charge mode, and closing the first switch 5 after the pre-charge is successful.

[0108] In this embodiment, when all battery packs whose pre-power-on instructions are 1 are powered on successfully, the system enters the discharge mode; otherwise, the system returns to the pre-processing operation.

[0109] In this embodiment, determining whether each battery group in the energy storage battery meets the power-on condition includes: obtaining a power-on voltage of the energy storage battery according to a charge and discharge mode of the energy storage battery, and determining a difference between a total voltage of each battery group in the energy storage battery and the power-on voltage; if the difference is within a preset threshold range, the battery group meets the power-on condition; if the difference is not within the preset threshold range, the battery group does not meet the power-on condition.

[0110] In this embodiment, the power-on voltage of the energy storage battery is obtained according to the charge and discharge mode of the energy storage battery. Specifically, if the charge and discharge mode is the discharge mode, the power-on voltage is the maximum voltage of each non-fault battery group in the energy storage battery; if the charge and discharge mode is the charge mode, the power-on voltage is the minimum voltage of each non-fault battery group in the energy storage battery.

[0111] In this embodiment, a pre-power-on instruction value is set for each battery pack, and whether the battery pack meets the power-on condition is determined according to the pre-power-on instruction value.

[0112] As a specific example of an embodiment of the present invention, if the pre-power-on instruction value is 1, the power-on condition is met, and if the pre-power-on instruction value is 2, the power-on condition is not met. The pre-power-on instruction in the battery pack is used to determine whether the battery pack in the energy storage battery meets the power-on condition.

[0113] In this embodiment, performing a balanced discharge voltage operation on each battery pack according to the first voltage includes:

[0114] Determining a current first voltage of the energy storage battery, where the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery;

[0115] Screening unpowered battery packs according to the first voltage and a preset first voltage difference to determine all second battery packs that meet a power-on condition;

[0116] limiting the total charge and discharge current of the energy storage battery according to the number of currently online battery packs, and powering on the second battery pack;

[0117] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced discharge voltage operation is completed.

[0118] In this embodiment, the battery with the highest voltage among all current battery packs is screened and recorded as a first voltage. The voltages of all current battery packs that do not meet the power-on conditions are determined. If the difference between the voltage of a battery pack that does not meet the power-on conditions and the first voltage is within a first threshold range and the battery pack is fault-free, the pre-power-on instruction for the battery pack is set to 1. Current limiting is then performed on the energy storage battery based on the number of currently online battery packs to control the battery pack to power on. The current limiting operation is released after power-on is complete.

[0119] In this embodiment, the current limiting operation on the energy storage battery according to the number of currently online battery groups includes: current limiting the total charge and discharge current in the energy storage battery, and the online battery group is a battery group with no faults and all batteries in the battery group are successfully powered on.

[0120] In this embodiment, the current limiting operation includes: sending a current limiting instruction to the master control battery of each battery pack according to the number of powered-on battery packs and a first current threshold, so as to limit the total charge and discharge current.

[0121] As a specific example of an embodiment of the present invention, when performing a current limiting operation, the total charge and discharge current of the energy storage battery is limited to (10A*number of online battery packs) A, wherein the online battery pack is a powered battery pack.

[0122] As a specific example of an embodiment of the present invention, the first threshold range is set to be greater than or equal to 2V and less than or equal to 4V. When performing a balanced discharge voltage operation on each battery pack according to the first voltage, the voltage of the battery pack with the highest current voltage is screened and recorded as the first voltage, and all battery packs that do not currently meet the power-on condition are judged, that is, when the difference between the voltage of the second battery pack with a pre-power-on instruction of 2 and the first voltage is greater than or equal to 2V or less than or equal to 4V, and the second battery pack has no faults, the pre-power-on instruction of the second battery pack is set to 1, and the total charge and discharge current inside the energy storage battery is limited to: (10*number of online battery packs) A, and a power-on instruction is sent to the second battery pack. After the second battery pack is powered on, the total charge and discharge current limit is released.

[0123] In this embodiment, performing a balanced charging voltage operation on each battery pack according to the second voltage includes:

[0124] Determining a current second voltage of the energy storage battery, where the second voltage is a minimum voltage of each non-faulty battery group in the energy storage battery;

[0125] Screening unpowered battery packs according to the second voltage and a preset second voltage difference to determine all third battery packs that meet a power-on condition;

[0126] Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery packs, and powering on the second battery pack;

[0127] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced charging voltage operation is completed.

[0128] In this embodiment, the lowest voltage among all battery packs currently without faults is recorded as the second voltage. The voltages of all battery packs currently not meeting the power-on conditions are determined. If the difference between the voltage of a battery pack that does not meet the power-on conditions and the second voltage is within a second threshold range, and the battery pack is fault-free, the pre-power-on instruction for that battery pack is set to 1. Current limiting is then performed on the energy storage battery based on the number of currently online battery packs to control the power-on operation of the third battery pack. The current limiting operation is released after power-on is complete.

[0129] In this embodiment, the current limiting operation on the energy storage battery according to the number of currently online battery groups includes: current limiting operation on the total charge and discharge current inside the energy storage battery, and the online battery group is a battery group with no faults and all batteries in the battery group are successfully powered on.

[0130] In this embodiment, the current limiting operation includes: sending a current limiting instruction to the master control battery of each battery pack according to the number of powered-on battery packs and a first current threshold, so as to limit the total charge and discharge current.

[0131] As a specific example of an embodiment of the present invention, when performing a current limiting operation, the total charge and discharge current of the energy storage battery is limited to (10A*number of online battery packs) A, wherein the online battery pack is a powered battery pack.

[0132] As a specific example of an embodiment of the present invention, the second threshold range is set to be greater than or equal to 2V and less than or equal to 4V. When performing a balancing charging voltage operation on each battery pack according to the second voltage, the voltage of the battery pack with the lowest current voltage is screened and recorded as the second voltage. All battery packs that do not currently meet the power-on condition are judged, that is, when the difference between the voltage of the third battery pack with a pre-power-on instruction of 2 and the second voltage is greater than or equal to 2V or less than or equal to 4V, and the third battery pack has no faults, the pre-power-on instruction of the third battery pack is set to 1, and the total charge and discharge current inside the energy storage battery is limited to: (10*number of online battery packs) A, and a power-on instruction is sent to the s battery pack. After the third battery pack is powered on, the total charge and discharge current limit is released.

[0133] In this embodiment, if a battery pack is not integrated into the system due to a large voltage differential, the energy storage battery can integrate the battery pack into the system during the charge and discharge process when the voltage differential meets a preset threshold, balancing the battery voltage and increasing system capacity. If a battery pack has a large voltage differential, the master control battery can adjust the internal wiring of the high-voltage battery until the battery voltages in the battery string are consistent.

[0134] An embodiment of the present invention further provides a method for eliminating energy storage battery faults, which is applied to the energy storage battery, comprising:

[0135] Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation;

[0136] After entering the discharge mode or the charging mode, when a faulty battery pack is detected, current limiting operations are performed on the battery packs other than the faulty battery pack according to the number of powered-on battery packs and the first current threshold to limit the total charge and discharge current; and a power-off instruction is sent to the faulty battery pack until the faulty battery pack is powered off, and then a current limiting release instruction is sent to each powered-on battery pack; wherein, the faulty battery pack is a powered-on battery pack with a serious battery fault.

[0137] In this embodiment, the current limiting operation includes: sending a current limiting instruction to the master control battery of each battery pack according to the number of powered-on battery packs and a first current threshold, so as to limit the total charge and discharge current.

[0138] As a specific example of an embodiment of the present invention, when performing a current limiting operation, the total charge and discharge current of the energy storage battery is limited to (10A*number of online battery packs) A, wherein the online battery pack is a powered battery pack.

[0139] In this embodiment, after entering discharge mode, voltage differentials are unavoidable within the energy storage battery due to differences in wiring harnesses and battery cells. In a single energy storage battery, if a voltage differential exists at the end of discharge, when the voltage of the lowest cell reaches the lower limit, the entire energy storage battery cannot continue to discharge. At this point, the remaining cells still have some charge remaining, resulting in a low capacity for the entire energy storage battery. For an energy storage battery composed of multiple cells, if the voltage of a cell reaches the lower limit at the end of discharge, the main control battery can power it off, allowing the remaining cells to continue discharging until the voltage of the last cell reaches the lower limit.

[0140] In this embodiment, determining whether the energy storage battery is fully discharged includes:

[0141] When entering the discharge mode, if the SOC value of a battery reaches the second threshold, the battery pack where the battery is located is current limited, and the battery that reaches the second threshold is powered off. After the power-off is completed, the current limiting operation is released.

[0142] In this embodiment, when the SOC value of the last battery reaches the second threshold, the connection of the last battery is retained, and the discharge current of the master battery is limited to 0.

[0143] As a specific example of an embodiment of the present invention, when the SOC value of a battery reaches 0% during discharge, the master battery requests from an external device that the current battery pack's discharge current be limited to 10A. It then sends a power-off command to the battery with the 0% SOC value. Once the battery with the 0% SOC value is confirmed to be powered off and disconnected, the discharge current of the current battery pack is restored. If the last battery in the current battery pack is about to reach 0%, the current battery remains connected, and the master battery limits the discharge current of the current battery pack to 0A.

[0144] In this embodiment, the power-off operation of the battery pack includes: the master control battery sends a power-off instruction to the first battery and the last battery in the battery pack, controls the first battery to disconnect the first switch 5, and controls the last battery to disconnect the second switch 6.

[0145] In this embodiment, when the external device sends a power-off instruction to the master battery, the master battery disconnects all batteries.

[0146] In this embodiment, determining whether the energy storage battery is fully charged includes:

[0147] When entering the charging mode, if the SOC value of a battery reaches the third threshold, the battery pack where the battery is located is current limited, and the battery that reaches the third threshold is powered off. After the power-off is completed, the current limiting operation is released.

[0148] In this embodiment, when the SOC value of the last battery reaches the third threshold, the connection of the last battery is retained, and the charging current of the master battery is limited to 0.

[0149] As a specific example of an embodiment of the present invention, when the SOC value of a battery reaches 100% during discharge, the master battery requests an external device to limit the charging current of the current battery pack to 10A. It then sends a power-off command to the battery with an SOC value of 100%. After confirming that the battery with an SOC value of 100% has been powered off and disconnected, the charging current of the current battery pack is restored. If the last battery in the current battery pack is about to reach 100%, the current battery remains connected, and the master battery limits the charging current of the current battery pack to 0A.

[0150] In this embodiment, when the external device sends a power-off instruction to the master battery, the master battery disconnects all batteries.

[0151] In this embodiment, by connecting several batteries in series and in parallel and eliminating the battery pack containing the faulty battery, when a battery seriously fails and can no longer support charging or discharging, the entire energy storage battery is current-limited and the battery pack containing the faulty battery is disconnected. The remaining battery packs can continue to operate normally, thereby increasing system redundancy. This prevents the entire energy storage system from shutting down when a single battery fails, thereby improving system operating efficiency.

[0152] An embodiment of the present invention further provides a method for charging and discharging an energy storage battery without switching, which is applied to the energy storage battery, comprising:

[0153] Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation;

[0154] The inductive switching operation includes: when detecting that there is a first battery pack that is in a powered-on state but does not meet the power-on conditions, sending a control instruction to the first battery; the first battery is the first battery in the first battery pack; the first battery adjusts the charge-discharge circuit 1 according to the control instruction and the switching operation, wherein the switching operation includes discharging to charging and charging to discharging.

[0155] In this embodiment, the first battery pack that is in a powered-on state but does not meet the power-on condition specifically refers to a battery pack that is in a powered-on state but has a pre-power-on instruction of 2.

[0156] In this embodiment, when it is detected that the energy storage battery is fully discharged, the charge-discharge circuit 1 is adjusted according to the control instruction and the switching operation, thereby entering the charging mode; the detection that the energy storage battery is fully discharged includes when it is detected that the internal current of the energy storage battery is negative, that is, the energy storage battery is fully discharged.

[0157] In this embodiment, before entering the charging mode according to the senseless switching operation, a pre-charging power-up operation is also performed on all battery packs. The pre-charging power-up operation includes: screening battery packs without battery failures on a battery pack basis, calculating the total voltage of the battery packs, obtaining the lowest voltage among all battery packs as a second power-up voltage, screening all battery packs that meet the power-up conditions based on the second power-up voltage, setting the pre-power-up instructions of the battery packs that meet the power-up conditions to 1, and setting the pre-power-up instructions of the battery packs that do not meet the power-up conditions to 2.

[0158] As a specific example of an embodiment of the present invention, screening out all battery packs meeting the power-on condition according to the second power-on voltage includes determining a battery pack whose difference between the battery pack voltage and the second power-on voltage is within a default threshold as a battery pack meeting the power-on condition.

[0159] In this embodiment, when it is detected that the energy storage battery is fully charged, the charge-discharge circuit 1 is adjusted according to the control instruction and the switching operation, thereby entering the discharge mode; the detection that the energy storage battery is fully charged includes when it is detected that the internal current of the energy storage battery is positive, that is, the energy storage battery is fully charged.

[0160] In this embodiment, before entering the discharge mode according to the senseless switching operation, a discharge pre-power-on operation is also performed on all battery packs. The discharge pre-power-on operation includes: screening battery packs without battery failures on a battery pack basis, calculating the total voltage of the battery pack, obtaining the highest voltage among all battery packs as a first power-on voltage, screening all battery packs that meet the power-on conditions based on the first power-on voltage, setting the pre-power-on instructions of the battery packs that meet the power-on conditions to 1, and setting the pre-power-on instructions of the battery packs that do not meet the power-on conditions to 2.

[0161] As a specific example of an embodiment of the present invention, screening out all battery packs meeting the power-on condition according to the first power-on voltage includes determining a battery pack whose voltage difference with the first power-on voltage is within a default threshold as a battery pack meeting the power-on condition.

[0162] In this embodiment, the switching operation includes discharging to charging and charging to discharging. After the first battery enters the inductive switching operation, the relay is closed according to the type of the switching operation.

[0163] In this embodiment, the first battery adjusts the charge-discharge circuit 1 according to the control instruction and the switching operation, including:

[0164] When the switching operation is from discharge to charge, the first battery is connected to the charging circuit provided with the second diode 13, and the first switch 5 is disconnected;

[0165] When the switching operation is from charge to discharge, the first battery is connected to the discharge circuit provided with the first diode 12 , and the first switch 5 is disconnected.

[0166] In this embodiment, after the charging pre-power-on operation is completed, if it is detected that the first battery pack is in the powered-on state but the pre-power-on instruction is 2, a senseless switching operation is entered. If the switching operation at this time is from discharge to charge, the master control battery of the first battery pack controls the first battery in the first battery pack to close the second switch 6, connecting it to the charging circuit, and open the first switch 5.

[0167] A second power-on operation is further included after the sensorless switching operation, and the second power-on operation includes:

[0168] Close the second switch 6 of the third battery and the fifth switch 11 of the first battery in all battery packs that meet the power-on condition;

[0169] Close the second switch 6 of the third battery and the first switch 5 of the first battery in all battery packs that do not meet the power-on condition;

[0170] The third battery is the last battery in the battery pack, and the first battery is the first battery in the battery pack.

[0171] In this embodiment, after the inductive switching operation of the first battery is completed, a second power-on operation is performed on all battery packs, and the charging mode is entered after the power-on is successful.

[0172] In this embodiment, after entering charging mode, voltage differences are unavoidable within the energy storage battery due to differences in wiring harnesses and battery cells. In a battery system composed of multiple cells, at the end of charging, when the voltage of a cell reaches the upper limit, the master control battery powers it on, and the remaining cells continue charging until the voltage of the last cell reaches the upper limit.

[0173] In this embodiment, the energy storage battery fully charges, including:

[0174] When entering the charging mode, if the SOC value of a battery reaches the third threshold, the battery pack where the battery is located is current limited, and the battery that reaches the third threshold is powered off. After the power-off is completed, the current limiting operation is released.

[0175] In this embodiment, when the SOC value of the last battery reaches the third threshold, the connection of the last battery is retained, and the charging current of the master battery is limited to 0.

[0176] As a specific example of an embodiment of the present invention, when the SOC value of a battery reaches 100% during discharge, the master battery requests an external device to limit the charging current of the current battery pack to 10A. It then sends a power-off command to the battery with an SOC value of 100%. After confirming that the battery with an SOC value of 100% has been powered off and disconnected, the charging current of the current battery pack is restored. If the last battery in the current battery pack is about to reach 100%, the current battery remains connected, and the master battery limits the charging current of the current battery pack to 0A.

[0177] In this embodiment, during the charge-discharge conversion, the terminal voltage is kept stable by switching the charging circuit and the discharging circuit in the battery, and the switching of high-voltage and low-voltage batteries is completed at the same time to avoid the sudden loss of terminal voltage connected to external devices caused by switching between battery packs. The entire switching operation will not affect the normal operation of the battery.

[0178] In this embodiment, before entering the discharge mode according to the inductive switching operation, the method further includes performing a discharge pre-power-up operation on all battery packs.

[0179] An embodiment of the present invention further provides an energy storage battery control method, which is applied to the energy storage battery, comprising:

[0180] Receive a power-on instruction, so that the master battery performs a first power-on operation on all batteries according to the power-on instruction, and enters a discharge mode after successful power-on; when it is detected that the energy storage battery is fully discharged, enters a charging mode according to a senseless switching operation; when it is detected that the energy storage battery is fully charged, enters a discharge mode according to the senseless switching operation;

[0181] In this embodiment, when the battery enters the discharge mode, a balanced discharge voltage operation is performed on each battery pack according to a first voltage; and a full discharge operation is performed according to the SOC value of all batteries; the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery;

[0182] When entering the charging mode, a balanced charging voltage operation is performed on each battery pack according to a second voltage; and a full charging operation is performed according to the SOC value of all batteries; the second voltage is the minimum voltage of each fault-free battery pack in the energy storage battery.

[0183] In this embodiment, the energy storage battery utilizes a CAN bus architecture to connect the battery packs. One battery in each pack is configured as a master battery, and the remaining batteries are configured as slave batteries. The energy storage battery comprises m battery packs connected in parallel, each of which includes n batteries. Within each battery pack, one battery is adaptively configured as the master battery, while the remaining batteries are configured as slave batteries. Configuration information sent by an external device calibrates the number of cells in the current energy storage battery, i.e., m battery packs consisting of n cells are connected in parallel. Each battery is calibrated using a DIP switch on the battery, with each cell numbered from 1 to n*m-1.

[0184] In this embodiment, the external device and each battery in the energy storage battery are connected via a CAN bus architecture. The battery connected to the external device CAN is adaptively set as the master battery, and the remaining batteries are set as slave batteries. The slave batteries set different CAN IDs according to their own serial numbers and send secondary battery information to the master battery via the intermediate CAN network. The master battery collects the secondary battery information of all slave batteries and its own primary battery information, processes it, and sends it to the external device.

[0185] In this embodiment, after the energy storage battery is started by receiving an instruction, a pre-processing operation is performed on the energy storage battery. The pre-processing operation includes: the energy storage battery performs an initialization self-test. After the self-test passes, the battery pack in the energy storage battery is pre-processed in series and discharged and pre-powered on.

[0186] In this embodiment, the battery pack enters the discharge mode after completing the series pre-processing and discharge pre-power-up operations, and performs a balanced discharge voltage operation on each battery pack according to the first voltage.

[0187] In this embodiment, performing a balanced discharge voltage operation on each battery pack according to the first voltage includes:

[0188] Determining a current first voltage of the energy storage battery, where the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery;

[0189] Screening unpowered battery packs according to the first voltage and a preset first voltage difference to determine all second battery packs that meet a power-on condition;

[0190] Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery packs, and powering on the second battery pack;

[0191] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced discharge voltage operation is completed.

[0192] In this embodiment, performing a balanced charging voltage operation on each battery pack according to the second voltage includes:

[0193] Determining a current second voltage of the energy storage battery, where the second voltage is a minimum voltage of each non-faulty battery group in the energy storage battery;

[0194] Screening unpowered battery packs according to the second voltage and a preset second voltage difference to determine all third battery packs that meet a power-on condition;

[0195] Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery packs, and powering on the second battery pack;

[0196] After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced charging voltage operation is completed.

[0197] In this embodiment, after entering the discharge mode or the charging mode, when a faulty battery group is detected, a current limiting instruction is sent to the battery groups other than the faulty battery group based on the number of powered-on battery groups and the first current threshold to limit the total charge and discharge current; and a power-off instruction is sent to the faulty battery group until the faulty battery group is powered off, and then a current limiting release instruction is sent to each powered-on battery group; wherein the faulty battery group is a powered-on battery group in which a serious battery fault occurs.

[0198] In this embodiment, the senseless switching operation includes:

[0199] When detecting that there is a first battery pack that is in a powered-on state but does not meet the power-on condition, sending a control instruction to the first battery; the first battery is the first battery in the first battery pack;

[0200] The first battery adjusts the charge-discharge circuit 1 according to the control instruction and the switching operation, wherein the switching operation includes discharging to charging and charging to discharging.

[0201] In this embodiment, the first battery adjusts the charge-discharge circuit 1 according to the control instruction and the switching operation, including:

[0202] When the switching operation is from discharge to charge, the fifth switch 11 of the first battery is closed to connect to the limited discharge branch provided with the second diode 13, and the first switch 5 is opened;

[0203] When the switching operation is from charge to discharge, the fourth switch 10 of the first battery is closed to connect to the limiting charging branch provided with the first diode 12, and the first switch 5 is opened.

[0204] In this embodiment, after entering discharge mode, voltage differentials are unavoidable within the energy storage battery due to issues such as wiring harness and cell variations. In a single energy storage battery, if a voltage differential exists at the end of discharge, when the voltage of the lowest cell reaches the lower limit, the entire energy storage battery cannot continue discharging. At this point, the remaining cells still have some charge remaining, resulting in a low capacity for the entire energy storage battery. For energy storage batteries composed of multiple cells, if the voltage of a cell reaches the lower limit at the end of discharge, the main control battery can power it off, allowing the remaining cells to continue discharging until the voltage of the last cell reaches the lower limit.

[0205] In this embodiment, determining whether the energy storage battery is fully discharged includes:

[0206] When entering the discharge mode, if the SOC value of a battery reaches the second threshold, the battery pack where the battery is located is current limited, and the battery that reaches the second threshold is powered off. After the power-off is completed, the current limiting operation is released.

[0207] In this embodiment, when the SOC value of the last battery reaches the second threshold, the connection of the last battery is retained, and the discharge current of the master battery is limited to 0.

[0208] As a specific example of an embodiment of the present invention, when the SOC value of a battery reaches 0% during discharge, the master battery requests from an external device that the current battery pack's discharge current be limited to 10A. It then sends a power-off command to the battery with the 0% SOC value. Once the battery with the 0% SOC value is confirmed to be powered off and disconnected, the discharge current of the current battery pack is restored. If the last battery in the current battery pack is about to reach 0%, the current battery remains connected, and the master battery limits the discharge current of the current battery pack to 0A.

[0209] In this embodiment, the power-off operation of the battery pack includes: the master control battery sends a power-off instruction to the first battery and the last battery in the battery pack, controls the first battery to disconnect the first switch 5, and controls the last battery to disconnect the second switch 6.

[0210] In this embodiment, when the external device sends a power-off instruction to the master battery, the master battery disconnects all batteries.

[0211] In this embodiment, determining whether the energy storage battery is fully charged includes:

[0212] When entering the charging mode, if the SOC value of a battery reaches the third threshold, the battery pack where the battery is located is current limited, and the battery that reaches the third threshold is powered off. After the power-off is completed, the current limiting operation is released.

[0213] In this embodiment, when the SOC value of the last battery reaches the third threshold, the connection of the last battery is retained, and the charging current of the master battery is limited to 0.

[0214] As a specific example of an embodiment of the present invention, when the SOC value of a battery reaches 100% during discharge, the master battery requests an external device to limit the charging current of the current battery pack to 10A. It then sends a power-off command to the battery with an SOC value of 100%. After confirming that the battery with an SOC value of 100% has been powered off and disconnected, the charging current of the current battery pack is restored. If the last battery in the current battery pack is about to reach 100%, the current battery remains connected, and the master battery limits the charging current of the current battery pack to 0A.

[0215] In this embodiment, when the external device sends a power-off instruction to the master battery, the master battery disconnects all batteries.

[0216] In this embodiment, after entering the discharge mode or the charging mode, when a faulty battery group is detected, a current limiting instruction is sent to the main control battery of each battery group according to the number of powered-on battery groups and the first current threshold to limit the total charge and discharge current; and a power-off instruction is sent to the faulty battery group until the faulty battery group is powered off, and then a current limiting release instruction is sent to the main control battery of each battery group; wherein, the faulty battery group is a powered-on battery group with a serious battery fault.

[0217] In this embodiment, several batteries are connected in series to form a battery pack, and several battery packs are connected in parallel to form an energy storage battery. During operation, each master control battery collects information from all batteries in the battery pack and sends it to an external device, so that when the modular battery is removed or added, the information collection and operation of other battery packs in the energy storage battery will not be affected. When a battery fails, it is only necessary to power off and repair the battery pack in which it is located without stopping the operation of the entire energy storage battery, thereby improving the operating efficiency of the entire energy storage battery and improving fault tolerance. At the same time, the overall total capacity of the energy storage battery can be increased by connecting in series and in parallel, thereby improving the scalability of the energy storage battery.

[0218] The specific embodiments described above further illustrate the objectives, technical solutions, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. An energy storage battery, characterized in that: comprising a plurality of battery packs connected in parallel, and each of the battery packs comprises a plurality of batteries connected in series; The battery comprises a charge and discharge circuit; the charge and discharge circuit comprises a storage battery, a first switch and a second switch; the first switch and the second switch are used to control the disconnection or closing of the connection line between the two batteries.

2. The energy storage battery according to claim 1, characterized in that: The battery includes a positive terminal and a negative terminal. In the charge and discharge circuit, the positive electrode of the battery is connected to the positive terminal, and the negative electrode of the battery is connected to the negative terminal. The first switch is arranged between the positive electrode of the battery and the positive terminal; and the second switch is arranged between the negative electrode of the battery and the negative terminal.

3. The energy storage battery according to claim 1, characterized in that: The battery further includes a charge and discharge limiting branch, and the charge and discharge limiting branch is arranged in parallel with the first switch.

4. The energy storage battery according to claim 3, characterized in that: The limiting charge and discharge branch includes a limiting charge branch and a limiting discharge branch; the limiting charge branch and the limiting discharge branch are arranged in parallel; The limiting charging branch includes a first diode and a fourth switch, wherein the first diode and the fourth switch are arranged in series between the positive electrode of the battery and the positive electrode terminal, and the positive electrode of the first diode is connected to the positive electrode of the battery; The limiting discharge branch includes a second diode and a fifth switch, wherein the second diode and the fifth switch are arranged in series between the positive electrode of the battery and the positive electrode terminal, and the cathode of the second diode is connected to the positive electrode of the battery.

5. The energy storage battery according to claim 1, characterized in that: The battery further includes a pre-charging branch, and the pre-charging branch is arranged in parallel with the first switch.

6. The energy storage battery according to claim 1, characterized in that: The pre-charging branch includes a pre-charging resistor and a third switch, and the pre-charging resistor and the third switch are arranged in series between the positive electrode of the battery and the positive electrode terminal.

7. The energy storage battery according to claim 1, characterized in that: The energy storage battery adopts a CAN bus architecture to connect various battery packs; one battery in the battery pack is set as a master control battery, and the remaining batteries are set as slave control batteries.

8. A method for balanced charging and discharging of an energy storage battery, characterized in that: The energy storage battery according to any one of claims 1 to 7 comprises: Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation; When the battery enters the discharge mode, a balanced discharge voltage operation is performed on each battery pack according to a first voltage; and a full discharge operation is performed according to the SOC value of all batteries; the first voltage is the maximum voltage of each non-fault battery pack in the energy storage battery; After entering the charging mode, a balanced charging voltage operation is performed on each battery pack according to a second voltage; and a full charging operation is performed according to the SOC value of all batteries; the second voltage is the minimum voltage of each fault-free battery pack in the energy storage battery.

9. The energy storage battery balanced charge and discharge method according to claim 8, characterized in that: The step of performing a balanced discharge voltage operation on each battery pack according to the first voltage includes: Determine a current first voltage of the energy storage battery, where the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery; Screening the unpowered battery packs according to the first voltage and a preset first voltage difference to determine all second battery packs that meet the power-on condition; Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery groups, and powering on the second battery group; After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced discharge voltage operation is completed.

10. The energy storage battery balanced charge and discharge method according to claim 8, characterized in that: The step of performing a balanced charging voltage operation on each battery pack according to the second voltage includes: Determine a current second voltage of the energy storage battery, where the second voltage is a minimum voltage of each non-faulty battery group in the energy storage battery; Screening the unpowered battery packs according to the second voltage and a preset second voltage difference to determine all third battery packs that meet the power-on condition; Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery groups, and powering on the second battery group; After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced charging voltage operation is completed.

11. A method for eliminating energy storage battery faults, characterized in that: The energy storage battery according to any one of claims 1 to 7 comprises: Starting the energy storage battery and entering a discharge mode; when detecting that the energy storage battery is fully discharged, entering a charge mode according to a senseless switching operation; when detecting that the energy storage battery is fully charged, entering a discharge mode according to the senseless switching operation; After entering the discharge mode or the charging mode, when a faulty battery group is detected, current limiting operations are performed on the battery groups other than the faulty battery group according to the number of powered-on battery groups and the first current threshold to limit the total charge and discharge current; and a power-off instruction is sent to the faulty battery group until the faulty battery group is powered off, and then a current limiting release instruction is sent to each powered-on battery group; wherein the faulty battery group is a powered-on battery group in which a serious battery fault occurs.

12. A method for charging and discharging energy storage batteries without inductive switching, characterized in that: The energy storage battery according to any one of claims 1 to 7 comprises: Start the energy storage battery and enter the discharge mode; when it is detected that the energy storage battery is fully discharged, enter the charging mode according to the senseless switching operation; when it is detected that the energy storage battery is fully charged, enter the discharge mode according to the senseless switching operation model; The inductive switching operation includes: when a first battery pack is detected to be in a powered-on state but does not meet the power-on condition, a control instruction is sent to the first battery; the first battery is the first battery in the first battery pack; the first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, wherein the switching operation includes discharging to charging and charging to discharging.

13. The energy storage battery non-sensing switching charging and discharging method according to claim 12, characterized in that: The first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, including: When the switching operation is discharging to charging, the fifth switch of the first battery is closed to access the limiting discharge branch provided with the second diode, and the first switch is opened; When the switching operation is charging to discharging, the fourth switch of the first battery is closed to access the limiting charging branch provided with the first diode, and the first switch is opened.

14. The energy storage battery non-sensing switching charging and discharging method according to claim 13, characterized in that: A second power-on operation is further included after the inductive switching operation, and the second power-on operation includes: Closing the second switch of the third battery and the fifth switch of the first battery in all battery packs that meet the power-on condition; Closing the second switch of the third battery and the first switch of the first battery in all battery packs that do not meet the power-on condition; The third battery is the last battery in the battery pack, and the first battery is the first battery in the battery pack.

15. A method for controlling an energy storage battery, characterized in that: The energy storage battery according to any one of claims 1 to 7 comprises: Receive a power-on instruction so that the master control battery performs a first power-on operation on all batteries according to the power-on instruction, and enters a discharge mode after successful power-on; when it is detected that the energy storage battery is fully discharged, enters a charge mode according to a senseless switching operation; when it is detected that the energy storage battery is fully charged, enters a discharge mode according to the senseless switching operation.

16. The energy storage battery control method according to claim 15, characterized in that: When the battery enters the discharge mode, a balanced discharge voltage operation is performed on each battery pack according to a first voltage; and a full discharge operation is performed according to the SOC value of all batteries; the first voltage is the maximum voltage of each non-fault battery pack in the energy storage battery; After entering the charging mode, a balanced charging voltage operation is performed on each battery pack according to a second voltage; and a full charging operation is performed according to the SOC value of all batteries; the second voltage is the minimum voltage of each fault-free battery pack in the energy storage battery.

17. The energy storage battery control method according to claim 16, characterized in that: The step of performing a balanced discharge voltage operation on each battery pack according to the first voltage includes: Determine a current first voltage of the energy storage battery, where the first voltage is the maximum voltage of each non-faulty battery pack in the energy storage battery; Screening the unpowered battery packs according to the first voltage and a preset first voltage difference to determine all second battery packs that meet the power-on condition; Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery groups, and powering on the second battery group; After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced discharge voltage operation is completed.

18. The energy storage battery control method according to claim 16, characterized in that: The step of performing a balanced charging voltage operation on each battery pack according to the second voltage includes: Determine a current second voltage of the energy storage battery, where the second voltage is a minimum voltage of each non-faulty battery group in the energy storage battery; Screening the unpowered battery packs according to the second voltage and a preset second voltage difference to determine all third battery packs that meet the power-on condition; Limiting the total charge and discharge current of the energy storage battery according to the number of current online battery groups, and powering on the second battery group; After the second battery pack completes the power-on operation, the total charge and discharge current limit of the energy storage battery is released, and the balanced charging voltage operation is completed.

19. The energy storage battery control method according to claim 15, characterized in that: After entering the discharge mode or the charging mode, when a faulty battery group is detected, a current limiting instruction is sent to the battery groups other than the faulty battery group according to the number of powered-on battery groups and the first current threshold to limit the total charge and discharge current; and a power-off instruction is sent to the faulty battery group until the faulty battery group is powered off, and then a current limiting release instruction is sent to each powered-on battery group; wherein the faulty battery group is a powered-on battery group in which a serious battery fault occurs.

20. The energy storage battery control method according to claim 15, characterized in that: The senseless switching operation includes: When it is detected that there is a first battery pack that is in a powered-on state but does not meet the power-on condition, a control instruction is sent to the first battery; the first battery is the first battery in the first battery pack; The first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, wherein the switching operation includes discharging to charging and charging to discharging.

21. The energy storage battery control method according to claim 20, characterized in that: The first battery adjusts the charge and discharge circuit according to the control instruction and the switching operation, including: When the switching operation is discharging to charging, the fifth switch of the first battery is closed to access the limiting discharge branch provided with the second diode, and the first switch is opened; When the switching operation is charging to discharging, the fourth switch of the first battery is closed to access the limiting charging branch provided with the first diode, and the first switch is opened.

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