WO2024193196A1 - Voltage balancing module and method, and energy storage apparatus and readable storage medium - Google Patents

Abstract

The present application relates to a voltage balancing module and method, and an energy storage apparatus and a readable storage medium, wherein the method is applied to an energy storage apparatus, and the energy storage apparatus comprises a high-voltage electrical module (300) and a battery module, which are electrically connected to each other, the voltage balancing module is integrated into the high-voltage electrical module (300), the battery module comprising a plurality of battery cells, and the voltage balancing module is used for balancing voltages among the plurality of battery cells. The voltage balancing module comprises: a main control sub-module (100), which is used for acquiring state of charge information of each battery cell, and determining, according to the state of charge information, a target battery cell to be subjected to balancing; and a balancing sub-module (200), which is used for performing state of charge balancing on the target battery cell.

Description

Voltage equalization module, method, energy storage device, and readable storage medium

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to a Chinese patent application filed with the China Patent Office on March 21, 2023, with application number 2023102791800 and invention name “voltage balancing module, method and energy storage device, readable storage medium”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of battery technology, and in particular to a voltage equalization module, method, energy storage device, and readable storage medium.

Background Art

The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

Lithium-ion batteries are a type of battery that uses lithium metal or lithium alloy as the negative electrode material and non-aqueous electrolyte solution. They have the characteristics of high energy density, no memory effect, high cycle life and low self-discharge rate, and are widely used in portable electronic products, power tools, electric vehicles, energy storage and other fields. When a group of lithium-ion batteries is charged and discharged, considering the inconsistency of each single cell, balancing measures can be taken to ensure the safety and stability of the battery, but the balancing effect produced by the currently designed balancing circuit is not obvious and the balancing current is small.

Summary of the invention

According to various embodiments of the present application, a voltage balancing module, method, energy storage device, and readable storage medium are provided.

In a first aspect, the present application provides a voltage equalization module, which is applied to an energy storage device, wherein the energy storage device comprises an electrically connected high-voltage electrical module and a battery module, wherein the voltage equalization module is integrated in the A high-voltage electrical module, wherein the battery module includes a plurality of single cells, and the voltage balancing module is used to balance the voltages between the plurality of single cells, and the voltage balancing module includes:

A main control submodule, used to obtain power information of each of the single cells, and determine a target single cell to be balanced according to the power information;

The balancing submodule is used to perform power balancing processing on the target single battery.

In a second aspect, the present application provides a voltage balancing method, which is applied to a voltage balancing module. The method includes:

The control main control submodule obtains the power information of each single cell, and determines the target single cell to be balanced according to the power information;

The control balancing submodule performs power balancing on the target single battery.

In a third aspect, the present application provides an energy storage device, comprising:

A high voltage electrical module, comprising a voltage equalization module as described above;

A battery module, electrically connected to the high voltage electrical module, the battery module comprising a plurality of single cells;

A battery detection module is connected to the battery module, and the battery detection module is used to detect the power information of each single battery.

In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the above-described method when executed by a processor.

The details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments or exemplary technologies of the present application, the drawings required for use in the description of the embodiments or exemplary technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of a voltage equalization module according to an embodiment of the present invention;

FIG2 is a second schematic diagram of the structure of a voltage balancing module provided in an embodiment;

FIG3 is a third schematic diagram of the structure of a voltage balancing module provided in an embodiment;

FIG. 4 is a schematic flow chart of a voltage balancing method provided in an embodiment.

DETAILED DESCRIPTION

In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

When used herein, the singular forms "a", "an", and "said/the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include/comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, in this specification, the term "and/or" includes any and all combinations of the relevant listed items.

The power supply used by electric vehicles and other equipment that uses power as an energy source has high requirements for voltage and current, so several single cells are usually combined in series into a battery module for use as a power source. However, there are inconsistencies between the single cells. Even if the batteries are produced by the same manufacturer and the same batch, during the production process, the inconsistency of the diaphragm, cathode material and anode material will cause inconsistency in the overall battery capacity; or during the battery charging and discharging process, even if the production and processing of the two battery cells are exactly the same, the thermal environment cannot always be consistent during the electrochemical reaction. For example, the temperature around the battery module is lower than that in the middle part, which causes long-term inconsistency in the charge and discharge amount, and then makes the battery capacity inconsistent. The above inconsistency will affect the entire battery module. Performance. This is because the capacity of the entire battery module system connected in series is determined by the single cell with the smallest capacity. Therefore, when the remaining capacity (State of Charge, SOC) of the single cell with the smallest capacity is very low during discharge, or the single cell with the smallest capacity is fully charged during charging, it is necessary to stop the discharge or charging of the entire battery module to prevent the single cell from being over-discharged or over-charged. However, the power of the remaining single cells cannot be fully utilized, resulting in a reduction in the actual available capacity of the battery module, affecting the use efficiency of the battery module, and increasing the number of charge and discharge cycles, thereby reducing the life of the battery module.

Therefore, in order to achieve more efficient battery module applications, a battery management system (BMS) is usually used to monitor and manage the battery module to prevent single cells from being overcharged or over-discharged, and to balance the battery module so that cells with inconsistent capacities become consistent in capacity, thereby reducing the impact of inconsistent battery capacities. However, the balancing effect produced by the existing BMS balancing method is not obvious, the balancing current cannot be further increased, and the heat dissipation of the balancing process is affected.

Based on this, the present application provides a voltage equalization module to overcome the above defects. In one embodiment, please refer to Figure 1. The voltage equalization module is applied to an energy storage device. The energy storage device includes an electrically connected high-voltage electrical module and a battery module. The voltage equalization module is integrated in the high-voltage electrical module. The battery module includes a plurality of single cells. The voltage equalization module is used to equalize the voltages between the plurality of single cells. The voltage equalization module includes a main control submodule 100 and a balancing submodule 200. The main control submodule 100 is used to obtain the power information of each of the single cells and determine the target single cell to be balanced according to the power information. The balancing submodule 200 is used to perform power equalization processing on the target single cell.

Specifically, the battery module may be composed of multiple groups of battery packs, each group being formed by a plurality of single cells connected in series (FIG. 1 is illustrated by taking the battery module divided into two groups of battery packs as an example). For example, in some embodiments, a power supply is formed by two groups of battery packs, each of which is composed of eight single cells connected in series, forming a total of 16 single cells connected in series. When the battery module is working, each of the single cells is charged simultaneously to store energy, or discharged simultaneously to provide electrical energy to electrical equipment. In one embodiment, the energy storage device also includes a slave control board connected to each single cell. The slave control board may be located in the battery module. The slave control board is used to collect the state parameters of each single cell so that the voltage balancing module can implement balancing control and thermal management control. The state parameters include but are not limited to the voltage and current of the single cell, the total voltage and total current of the battery module, the temperature, etc. That is, the state parameters can characterize the power information and Temperature information.

Furthermore, the slave control board can communicate data with the main control submodule 100 through the CAN bus, and the main control submodule 100 then obtains the power information of each single cell, and calculates and analyzes the single cell that needs to be balanced according to the power information, and uses it as the target single cell, wherein balancing means that the high-energy target single cell is charged slowly and the low-energy target single cell is charged quickly during the charging process, and the above situation is the opposite during the discharging process. Furthermore, the main control submodule 100 sends a balancing instruction to the balancing submodule 200, and controls the balancing submodule 200 to connect with the target single cell, thereby realizing the power balancing processing of the target single cell, so that the battery module can achieve the effect of consistent power of all single cells during charging and discharging.

Optionally, the balancing submodule 200 can actively balance the target single cell battery, or it can passively balance the target single cell battery. It should be noted that since the existing BMS balancing method is integrated into the battery module, the battery module has limited space, so the battery balancing effect is not obvious, the balancing current cannot be further improved due to the influence of space, and the heat dissipation of the balancing process is affected. Therefore, the main control submodule 100 and the balancing submodule 200 are both arranged in the high-voltage electrical module 300. The high-voltage electrical module 300 can be a high-voltage box with a large space, that is, the balancing method is all pulled into the high-voltage electrical module 300. If the balancing submodule 200 performs passive balancing on the target single cell battery, the main control submodule 100 controls the target single cell battery to be connected with the shunt circuit in the balancing submodule 200 to shunt the target single cell battery, thereby ensuring a more accurate balancing state between each single cell battery. Since the balancing submodule 200 is arranged in the high-voltage electrical module 300, the space is released. First, it is conducive to better heat dissipation of the shunt process, and second, the shunt circuit is no longer limited to the circuit board of the battery module, but It can be arranged in a high-voltage electrical module 300 with a larger space, so the shunt circuit can select high-power circuit devices to increase the balancing current and make the balancing effect more obvious; if the balancing submodule 200 actively balances the target single cell, the main control submodule 100 controls the balancing submodule 200 to transfer the energy of the target single cell to discharge the target single cell and charge the remaining single cells, thereby achieving a consistent and healthy charge state for each single cell. Since the balancing submodule 200 is arranged in the high-voltage electrical module 300, the dedicated control chip or integrated circuit used for active balancing is no longer limited to the circuit board of the battery module, but can be arranged in the high-voltage electrical module 300 with a larger space, by This enables the design of active equalization-related circuit structures with more complete functions, thereby achieving an increase in equalization power as required.

In the above example, by integrating the main control submodule 100 and the balancing submodule 200 into the high-voltage electrical module 300, the main control submodule 100 determines the target single cell that needs to be balanced based on the power information of each single cell obtained, and the balancing submodule 200 performs power balancing on the target single cell. Since the balancing submodule 200 is designed in the high-voltage electrical module 300, the balancing space is released, and a more powerful balancing method can be designed to increase the balancing current and make the balancing effect more obvious, so as to ensure that each single cell maintains the same state during normal use.

In one embodiment, please refer to Figure 2, the power information includes a voltage signal, and the main control submodule is also used to control the balancing submodule to be connected to the target single cell. The main control submodule 100 includes a main controller 101, a switch control unit 102 and a selection unit 103, wherein the main controller 101 is used to determine the target single cell to be balanced according to the voltage signal of each of the single cells, and output a balancing control signal.

It can be understood that since the voltage signal of a single cell is the most intuitive measurement quantity representing its state of charge, in this embodiment, the main controller 101 obtains the voltage signal of each single cell and analyzes the target single cell to be balanced according to the balancing control strategy. In some embodiments, the balancing control strategy can be to calculate the average voltage value of all current single cells, and the average voltage value is used as a standard to measure whether each single cell has reached the balance. If the main controller 101 determines that the difference between the voltage value of a certain single cell and the average voltage value exceeds a preset threshold, the single cell is determined to be the target single cell, and the main controller 101 needs to output a balancing control signal to start the balancing process. The judgment step is continuously performed during the balancing process until the difference does not exceed the preset threshold, indicating that each single cell has been balanced and has reached a state of consistent power, and the main controller 101 then stops outputting the balancing control signal. It should be noted that there are different ways to implement the balancing control strategy, and this application does not limit this strategy.

The switch control unit 102 is connected to the main controller 101, and is used to output a gating signal according to the balancing control signal; the gating unit 103 is connected to the switch control unit 102 and the balancing submodule 200 respectively, and is used to connect the target single cell to the balancing submodule 200 according to the gating signal. When balancing is required, the single cell is determined as the target single cell, and a balancing control signal is sent to the switch control unit 102 to instruct the switch control unit 102 to output a corresponding selection signal to control the selection unit 103 to be connected to the balancing submodule 200, and the selection unit 103 is connected to each single cell, that is, the selection signal is used to instruct the selection unit 103 to form a loop with the target single cell and the balancing submodule 200, so as to achieve the effect of controlling the balancing of the battery.

In one embodiment, the number of single cells is N, and the gating unit includes 2N+1 switching devices, wherein the positive electrode of the Nth single cell is connected to the 2N-1th switching device, the negative electrode of the Nth single cell is connected to the 2N+1th switching device, and the 2N-1th switching device is connected to the 2N+1th switching device through the 2Nth switching device; the gating unit is used to close the target switching device corresponding to the target single cell and disconnect the remaining switching devices according to the gating signal, so that the target single cell and the balancing submodule form a closed loop.

As shown in FIG. 3 , FIG. 3 is illustrated by taking 16 single cells and 33 switch devices as an example, wherein the 16 single cells are divided into two groups, each group is composed of 8 single cells, and the switch devices are marked as K1, ..., K33 in sequence. Optionally, since the relay has good conduction and isolation effects, the switch device can be a relay. Specifically, the selection signal is divided into a high level state and a low level state. When the switch control unit 102 outputs a selection signal in a high level state to control a certain switch device, the switch device receives the high level to be in a closed state. Similarly, when the switch device receives a low level, it is in an open state. In addition, the switch device is in an open state by default when it does not receive the selection signal.

Furthermore, the positive electrode of the Nth single cell is connected to one end of the balancing submodule 200 through the 2N-1th switch device, and the negative electrode of the Nth single cell is connected to the other end of the balancing submodule 200 through the 2N+1th switch device. If the Nth single cell needs to form a loop with the balancing submodule 200 alone, in addition to closing the 2N-1th switch device and the 2N+1th switch device, it is also necessary to close the remaining even-numbered switch devices except the 2Nth switch device, and the remaining switch devices are in the disconnected state. It should be noted that since the battery module is electrically isolated from the high-voltage electrical module, the balancing lines drawn from the positive and negative electrodes of each single cell need to be connected to the corresponding switch devices in sequence through the balancing harness connector on the battery module and the balancing harness connector on the high-voltage electrical module, and in this embodiment, Each single battery is connected to the slave control board through a sampling harness, and the battery detection module on the slave control board can further collect the status information of each single battery.

Exemplarily, when the main controller 101 detects that the voltage of the third single cell is too high and needs to be balanced, it sends a balancing control signal to the switch control unit 102, and the switch control unit 102 then outputs a selection signal to make the switch devices K2, K4, K5, K7, K8, K10, K12, K14, K16, K18, K20, K22, K24, K26, K28, K30 and K32 at a high level to achieve a closed state, thereby the third single cell can be connected to the balancing submodule 200 alone to form a closed loop, and then perform power balancing.

In one embodiment, referring to FIG. 3 , in the passive balancing mode, the balancing submodule 200 includes a passive balancing unit 201 , and the passive balancing unit 201 is used to perform a discharge process on the target single battery so that the power of each single battery is balanced.

Specifically, the main controller 101 determines the single cell with too high voltage as the target single cell, and controls the target single cell to be connected to the passive balancing unit 201, so that the passive balancing unit 201 discharges the target single cell, and the excess power of the target single cell is dissipated in the form of heat. For example, when single cell 2 reaches a fully charged state faster than the other single cells, the main controller 101 turns on the passive balancing unit 201 to discharge single cell 2, so that the excess power of single cell 2 is dissipated in the form of heat, and then continues to charge until the remaining single cells are fully charged. The passive balancing unit 201 is a dissipative balancing, which can discharge single cells with high voltage, which is not only low in cost, but also simple in circuit design.

In one embodiment, the passive balancing unit 201 includes a power resistor 2011 . The power resistor 2011 is connected to the target single battery. The power resistor 2011 is used to consume excess electrical energy in the target single battery.

It can be understood that when the target single cell is connected to the passive balancing unit 201, the target single cell is controlled to be connected in parallel with the power resistor 2011 to shunt the target single cell so that its excess electric energy is dissipated in the form of heat energy, ensuring that each single cell will not be overcharged or over-discharged, thereby extending the service life of the battery module. Furthermore, since the passive balancing unit 201 is arranged in the high-voltage electrical module 300, the size of the power resistor 2011 is no longer limited to the circuit board space of the battery module. In order to increase the power of the power resistor 2011 and make the balancing current larger, a larger volume can be arranged in the high-voltage electrical module 300. In addition, the power resistor 2011 generates a lot of heat during the discharge process, and the power resistor 2011 in the high-voltage electrical module 300 can achieve a better heat dissipation effect due to the freed space, thus avoiding the situation where the balancing efficiency is reduced due to excessive temperature.

In one embodiment, as shown in FIG. 3 , in active balancing mode, the balancing submodule 200 includes an active balancing unit 202 , which is used to transfer the electric energy of the target single cell to other single cells except the target single cell, so that the electric energy of each single cell is balanced.

It can be understood that the active balancing unit 202 can redistribute the electric energy during charging and discharging, and transfer the energy of the single cell with high voltage to the single cell with low voltage through the algorithm, that is, discharge the single cell with high voltage, and use the released energy to charge the single cell with low voltage. The active balancing unit 202 realizes power balancing by transferring electric energy and cutting high and supplementing low, which can minimize energy loss and improve the utilization efficiency of electric energy.

In one embodiment, as shown in FIG. 3 , the active balancing unit 202 includes a DC/DC conversion circuit 2021 and a DC bus 2022, wherein the input end of the DC/DC conversion circuit 2021 is connected to the selection unit 103, and the output end of the DC/DC conversion circuit 2021 is connected to the DC bus 2022; wherein the DC/DC conversion circuit 2021 is used to convert the electric energy of the target single cell battery and transfer it to other single cells except the target single cell battery via the DC bus 2022.

Specifically, the positive input end of the DC/DC conversion circuit 2021 is connected to the positive electrode of the target single battery through the gating unit 103, and the negative input end of the DC/DC conversion circuit 2021 is connected to the negative electrode of the target single battery through the gating unit 103. The DC/DC conversion circuit 2021 extracts the excess electric energy of the target single battery, converts the electric energy into a voltage that can be used by the DC bus 2022, and transfers the voltage to the DC bus 2022 to charge all the remaining single batteries, thereby realizing energy redistribution. Furthermore, since the active balancing unit 202 is arranged in the high-voltage electrical module 300, the DC/DC conversion circuit 2021 and other related active balancing circuits can be arranged on a separate circuit board, which is not affected by space, and a DC/DC conversion circuit with greater balancing power and more complete functions can be designed, thereby achieving better balancing effect and balancing speed.

In one embodiment, in the active balancing mode, the switch control unit is further used to send a response signal to the main controller after the target single battery is connected to the balancing submodule, and the main controller is further used to According to the response signal, an enable signal is sent to the balancing submodule to start the DC/DC conversion circuit. It can be understood that in the active balancing mode, when the main controller detects that a single cell is too high and needs to be balanced, it sends a balancing control signal to the switch control unit, and the switch control unit then outputs a selection signal to close the target switch device corresponding to the single cell. At the same time, the switch control unit sends a response signal back to the main controller to indicate that the single cell is connected to the balancing submodule. After receiving the response signal, the main controller sends an enable signal to the balancing submodule, thereby turning on the DC/DC conversion circuit in the active balancing unit, so that the single cell and the DC/DC conversion circuit form a separate loop for active balancing processing.

In one embodiment, the main controller 101 is further used to receive a switching instruction, wherein the switching instruction is used to instruct the main controller 101 to control the balancing submodule 200 to switch the balancing mode; the balancing mode includes an active balancing mode and a passive balancing mode.

It can be understood that the main controller 101 is used not only to control the operation of each module in the voltage balancing module, but also to communicate with the outside world, such as interacting with the upper-level master control system. In the balancing submodule 200, the active balancing unit 202 is compatible with the passive balancing unit 201, and the active balancing mode and the passive balancing mode become optional. The user can choose the active balancing mode or the passive balancing mode according to the cost and performance requirements. Therefore, the user can issue a switching instruction through the upper-level master control system, and transmit the switching instruction to the main controller 101 through the CAN protocol. For example, if the switching instruction instructs the voltage balancing module to implement the active balancing solution, and when the main controller 101 detects that the voltage of the fifth single cell is too high and needs to be balanced, it sends a balancing control signal to the switch control unit 102, and the switch control unit 102 further outputs a selection signal to enable the switch devices K2, K4, K6, K8, K9, K11, K12, K14, K16, K18, K20, K22, K24 , K26, K28, K30 and K32 are at a high level to achieve a closed state, and at the same time, the switch control unit 102 sends a response signal back to the main controller 101 to indicate that the fifth single cell to be balanced has been turned on separately. After receiving the response signal, the main controller 101 sends an enable signal to the balancing submodule to start the DC/DC conversion circuit 2021. In this way, the fifth single cell to be balanced and the DC/DC conversion circuit 2021 form a separate closed loop, and its excessive electric energy is sent to the DC bus 2022 to achieve the effect of reducing the voltage.

In this embodiment, the balancing submodule 200 provides more balancing schemes to choose from, making the active balancing mode compatible with the passive balancing module, and the user can freely switch the active balancing mode according to the needs. It supports both passive and dynamic balancing modes, and is not limited to a single balancing mode. The structure of the entire voltage balancing module is simple, which is conducive to program writing.

In one embodiment, based on the same inventive concept, the present application provides a voltage balancing method, which is applied to a voltage balancing module. As shown in FIG. 4 , the method includes steps S100 to S200 .

Step S100: Control the main control submodule to obtain the power information of each single cell, and determine the target single cell to be balanced according to the power information. Please refer to the relevant description of the above embodiment for step S100, which will not be repeated here.

Step S200: Control the balancing submodule to balance the target single battery. Please refer to the relevant description of the above embodiment for step S200, which will not be repeated here.

The voltage balancing method obtains the power information of each single cell through the main control submodule, determines the target single cell that needs to be balanced, connects the balancing submodule with the target single cell by the main control submodule, and then controls the balancing submodule to balance the power of the target single cell. Since the balancing submodule is designed in the high-voltage electrical module, the balancing space is released, and a more powerful balancing method can be designed to increase the balancing current and make the balancing effect more obvious, so as to ensure that each single cell maintains the same state during normal use.

The present application provides an energy storage device, including a high-voltage electrical module, a battery module and a battery detection module. Among them, the high-voltage electrical module includes the voltage equalization module described in the above embodiment, the battery module is electrically connected to the high-voltage electrical module, the battery module includes a plurality of single cells, the battery detection module is connected to the battery module, and the battery detection module is used to detect the power information of each single cell. Please refer to Figure 3. The battery module can be divided into a plurality of battery groups, each battery group is composed of a plurality of single cells, and each group is respectively connected to the battery detection module. The battery detection module can be arranged on the slave control board to detect the status information of each single cell, including the power information and temperature information of each single cell, so that the energy storage device can collect the parameter information of each single cell in real time during the charging and discharging process of the battery module, so as to analyze the target single cell that affects the consistency of the battery module, and perform equalization processing on it, so that each single cell achieves power balance and maintains the working efficiency and service life of the battery module.

In one embodiment, a plurality of single cells are connected in series, and the positive and negative electrodes of each single cell are connected to a balancing line. In the series structure, the negative and positive electrodes of adjacent single cells are connected to the balancing line. Share a balance line.

Among them, the positive and negative electrodes of each single cell are connected to the corresponding switch device through the equalization line, and because the battery module is isolated from the high-voltage electrical module, the equalization line of each single cell is connected to the corresponding switch device through the equalization harness connector on the battery module and the equalization harness connector on the high-voltage electrical module in turn. Furthermore, each single cell is also connected to the battery detection module through the sampling harness, so that the battery detection module can perform the collection work.

The present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiment are implemented.

It should be understood that, although the various steps in the flowchart of Fig. 4 are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in Fig. 4 may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features of the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present application, which all belong to the protection scope of the present application. Therefore, the protection scope of the patent application is The appended claims shall prevail.

Claims (15)

A voltage equalization module is applied to an energy storage device, the energy storage device includes a high-voltage electrical module and a battery module that are electrically connected, the voltage equalization module is integrated in the high-voltage electrical module, the battery module includes a plurality of single cells, the voltage equalization module is used to equalize the voltages between the plurality of single cells, and the voltage equalization module includes: A main control submodule, used to obtain power information of each of the single cells, and determine a target single cell to be balanced according to the power information; The balancing submodule is used to perform power balancing processing on the target single battery. The voltage equalization module according to claim 1, wherein the power information includes a voltage signal, the main control submodule is further used to control the equalization submodule to communicate with the target single battery, and the main control submodule includes: A main controller, used to determine the target single cell to be balanced according to the voltage signal of each single cell, and output a balancing control signal; A switch control unit connected to the main controller, the switch control unit is used to output a gating signal according to the equalization control signal; A gating unit is connected to the switch control unit and the balancing submodule respectively, and the gating unit is used to connect the target single battery and the balancing submodule according to the gating signal. The voltage equalization module according to claim 2, wherein the number of the single cells is N, and the gating unit comprises: 2N+1 switching devices; the positive electrode of the Nth single cell is connected to the 2N-1th switching device, the negative electrode of the Nth single cell is connected to the 2N+1th switching device, and the 2N-1th switching device is connected to the 2N+1th switching device through the 2Nth switching device; The gating unit is used to close the target switch device corresponding to the target single cell and disconnect the remaining switch devices according to the gating signal, so that the target single cell and the balancing submodule form a closed loop. The voltage balancing module according to claim 2, wherein the main controller is further used to receive a switching instruction, wherein the switching instruction is used to instruct the main controller to control the balancing submodule to perform balancing. The balancing mode includes an active balancing mode and a passive balancing mode. The voltage balancing module according to claim 2, wherein in the active balancing mode, the balancing submodule comprises: The active balancing unit is used to transfer the electric energy of the target single cell to the other single cells except the target single cell, so that the electric energy of each single cell is balanced. The voltage equalization module according to claim 5, wherein the active equalization unit comprises a DC/DC conversion circuit and a DC bus; The input end of the DC/DC conversion circuit is connected to the gating unit, and the output end of the DC/DC conversion circuit is connected to the DC bus; The DC/DC conversion circuit is used to convert the electric energy of the target single cell and transfer it to the other single cells except the target single cell via the DC bus. The voltage balancing module according to claim 6, wherein in the active balancing mode, the switch control unit is further used to send a response signal to the main controller after the target single cell is connected to the balancing submodule, and the main controller is further used to send an enable signal to the balancing submodule according to the response signal to start the DC/DC conversion circuit. The voltage balancing module according to claim 2, wherein in the passive balancing mode, the balancing submodule further comprises: The passive balancing unit is used to perform discharge processing on the target single battery so as to achieve power balance among the single batteries. The voltage balancing module according to claim 8, wherein the passive balancing unit comprises: A power resistor is connected to the target single battery, and the power resistor is used to consume excess electric energy in the target single battery. The voltage equalization module according to claim 1, wherein the energy storage device further comprises a slave control board connected to each of the single cells and the main control submodule, and the slave control board is used to collect state parameters of each of the single cells; The main control submodule is used to obtain the power information of each of the single cells according to the state parameters. A voltage balancing method is applied to a voltage balancing module, the method comprising: Control the main control submodule to obtain power information of each single cell, and determine the target single cell to be balanced according to the power information; and The control balancing submodule performs power balancing on the target single battery. An energy storage device, comprising: A high voltage electrical module, comprising a voltage equalization module as claimed in any one of claims 1 to 10; A battery module, electrically connected to the high voltage electrical module, the battery module comprising a plurality of single cells; A battery detection module is connected to the battery module, and the battery detection module is used to detect the power information of each single battery. The energy storage device according to claim 12, wherein a plurality of said single cells are in a series structure; The positive electrode and the negative electrode of each single cell are respectively connected to a balancing line; In the series structure, the negative electrodes and positive electrodes of the adjacent single cells share a balancing line. The energy storage device according to claim 12, wherein the battery module comprises: A slave control board, connected to the master control submodule and each of the single cells, respectively, and used to collect status parameters of each of the single cells; The main control submodule is used to obtain the power information of each of the single cells according to the state parameters. A computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method of claim 11.