A dual-matrix equalization energy storage multi-cluster battery system

Abstract

The utility model discloses a kind of double-matrix equalization energy storage multi-cluster battery pack systems, including several parallel battery clusters, battery cluster includes several series battery module, and battery module includes several series battery core;Still include DCDC voltage reduction module, first switch matrix module and second switch matrix module;The utility model solves the equalization method used in current industry appears only can be balanced within this cluster battery pack and cannot be balanced between cluster and cluster in system Problem, also avoid the problem of poor equalization effect and large heat generation due to the use of traditional passive equalization;In the realization equalization process, unique double-matrix control method is used, so that the whole energy storage system is intelligently and automatically balanced, so that the battery core in the whole energy storage system is balanced and tends to be consistent.

Description

Technical Field

[0001] This utility model relates to the field of battery charging and discharging systems, specifically a dual-matrix balanced energy storage multi-cluster battery pack system. Background Technology

[0002] Lithium battery systems are increasingly being used in new energy vehicles, energy storage systems, and other new energy application scenarios. Lithium-ion battery pack systems are equipped with corresponding BMS systems to monitor, balance, and manage the charging and discharging of batteries. However, the current balancing methods all adopt active and passive balancing within the cluster, and mutual balancing between clusters is not possible.

[0003] Currently, in the application of new energy fields, BMS generally adopts two forms of balancing: passive balancing and active balancing, as follows:

[0004] I. Passive Equilibrium:

[0005] Generally, after sampling the voltage of each individual cell in the entire battery pack, the cell with the highest voltage is then connected to the circuit of the cell and the equalization resistor by closing the MOS switch as shown in the figure below, and the cell with the highest voltage is discharged, so that the voltage of all cells is consistent.

[0006] like Figure 5 As shown, in a battery pack composed of BAT1, BAT2, ..., if the second cell is detected to have the highest voltage, the gate of the MOSFET drives CB2 to a high-level signal, turning on MOSFET2. BAT2 and R31 form a discharge circuit, discharging BAT2 and gradually aligning the voltage of the other cells in the series with BAT2. However, since voltage alignment is achieved through discharge, resistive discharge generates heat, and the excessive MOSFET switching current leads to unreliability. Therefore, current passive balancing methods in the industry only achieve a discharge current of around 100mA, resulting in slow balancing speed, low efficiency, and poor performance.

[0007] II. Active Equilibrium

[0008] Another less commonly used active balancing method in the industry is to charge the lowest voltage cell so that it can gradually reach the same circuit as the other cells.

[0009] like Figure 6 As shown, by detecting the voltage of individual cells in the series-connected battery, the voltage of the lowest-voltage individual cell in the step-down DC / DC output group is supplemented through the output of the entire battery pack, so that the lowest-voltage cell can reach the same level as the other individual cells.

[0010] Since these two methods only achieve equalization within the same cluster, they cannot achieve consistent equalization when batteries in different clusters are working, resulting in large circulating current. Furthermore, since equalization within a cluster can only balance the batteries within that cluster, it cannot achieve consistent synchronization of all cells in the entire energy storage system, and the inconsistency worsens with the increase in the number of usage cycles.

[0011] Therefore, it is necessary to improve such a structure to overcome the above-mentioned defects. Utility Model Content

[0012] The purpose of this invention is to provide a dual-matrix balanced energy storage multi-cluster battery pack system to solve the problems mentioned in the background art.

[0013] To achieve the above objectives, this utility model provides the following technical solution:

[0014] A dual-matrix balanced energy storage multi-cluster battery pack system includes several parallel battery clusters, each battery cluster including several series-connected battery modules, and each battery module including several series-connected battery cells; it also includes a DC-DC step-down module, a first switching matrix module, and a second switching matrix module.

[0015] The DC-DC step-down module is connected to the positive terminal of each battery cluster through its positive input terminal and to the negative terminal of each battery cluster through its negative input terminal. It is connected to the positive input terminal of the first switch matrix module through its first positive output terminal and to the negative input terminal of the first switch matrix module through its first negative output terminal. It is also connected to the positive input terminal of the second switch matrix module through its second positive output terminal and to the negative input terminal of the second switch matrix module through its second negative input terminal. This module is used to step down the voltage signal input from the battery cluster and output a first voltage signal and a second voltage signal to the first switch matrix module and the second switch matrix module, respectively.

[0016] The first switch matrix module is connected to the positive terminal of each battery module through multiple first positive output terminals and to the negative terminal of each battery module through multiple first negative output terminals, for controlling the output of the first voltage signal to charge the battery module with the lowest voltage among all the battery clusters;

[0017] The second switch matrix module is connected to the positive terminal of each cell in each battery cluster through multiple second positive output terminals and to the negative terminal of each cell in each battery cluster through multiple second negative output terminals, for controlling the output of the second voltage signal to charge the cell with the lowest voltage in each battery cluster.

[0018] Furthermore, the first switch matrix module includes:

[0019] The first input control unit is connected to the first positive output terminal of the DC-DC step-down module through a positive input terminal, to the first negative output terminal of the DC-DC step-down module through a negative input terminal, to the positive input terminal of the first output control unit through a positive output terminal, and to the negative input terminal of the first output control unit through a negative output terminal, and is used to control the input of the first voltage signal to the first switch matrix module;

[0020] The first output control unit is connected to the positive terminal of each battery module in each battery cluster through multiple first positive output terminals and to the negative terminal of each battery module through multiple first negative output terminals. It is used to control the first voltage signal output of the first switch matrix module to charge the battery module with the lowest voltage in all the battery clusters.

[0021] The second switch matrix module includes:

[0022] The second input control unit is connected to the second positive output terminal of the DC-DC step-down module through its positive input terminal, and to the second negative output terminal of the DC-DC step-down module through its negative input terminal. It is also connected to the positive input terminal of the second output control unit through its positive output terminal and to the negative input terminal of the second output control unit through its negative output terminal. It is used to control the input of the second voltage signal to the second switch matrix module.

[0023] The second output control unit is connected to the positive terminal of each cell in each battery cluster through multiple second positive output terminals and to the negative terminal of each cell through multiple second negative output terminals. It is used to control the second voltage signal output of the second switch matrix module to charge the cell with the lowest voltage in all battery clusters.

[0024] Furthermore, the first input control unit includes:

[0025] The first positive input switch is connected between the first positive output terminal of the DC-DC step-down module and the positive input terminal of the first output control unit.

[0026] The first negative input switch is connected between the first negative output terminal of the DC-DC step-down module and the negative input terminal of the first output control unit.

[0027] The second input control unit includes:

[0028] The second positive input switch is connected between the second positive output terminal of the DC-DC step-down module and the positive input terminal of the second output control unit.

[0029] The second negative input switch is connected between the second negative output terminal of the DC-DC step-down module and the negative input terminal of the second output control unit.

[0030] Furthermore, the first output control unit includes:

[0031] Multiple first positive output switches, each first positive output switch corresponding to one of the battery modules, are connected between the positive output terminal of the first input control unit and the positive terminal of the battery module;

[0032] Multiple first negative output switches, each first negative output switch corresponding to one of the battery modules, are connected between the negative output terminal of the first input control unit and the negative terminal of the battery module;

[0033] The second output control unit includes:

[0034] Multiple second positive output switches, each corresponding to one of the battery cells, are connected between the positive output terminal of the second input control unit and the positive terminal of the battery cell;

[0035] Multiple second negative output switches, each corresponding to one of the battery cells, are connected between the negative output terminal of the second input control unit and the negative terminal of the battery cell.

[0036] Compared with the prior art, the beneficial effects of this utility model are:

[0037] It mainly addresses the problems of inconsistent systems, rapid degradation, and poor safety caused by inconsistencies between clusters, modules, and cells, as well as inconsistencies generated during use.

[0038] It also solves the problem that the current balancing methods used in the industry can only balance within the same battery cluster and cannot balance between clusters within the system. It also avoids the problems of poor balancing effect and high heat generation caused by the use of traditional passive balancing.

[0039] The system employs a unique dual-matrix control method to achieve intelligent and automatic balancing within the entire energy storage system, thereby ensuring that the cell balance within the entire system tends to be consistent. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of a dual-matrix balanced energy storage multi-cluster battery pack system.

[0041] Figure 2 This is a detailed functional block diagram of a dual-matrix balanced energy storage multi-cluster battery pack system.

[0042] Figure 3 This is a schematic diagram of a dual-matrix balanced energy storage multi-cluster battery pack system.

[0043] Figure 4 This is a schematic diagram of the output principle of the DC-DC step-down module in a dual-matrix balanced energy storage multi-cluster battery pack system.

[0044] Figure 5 This is a schematic diagram of the passive equilibrium principle.

[0045] Figure 6 This is a schematic diagram illustrating the active DC / DC balancing principle. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0047] Please see Figure 1-4 A dual-matrix balanced energy storage multi-cluster battery pack system includes several parallel battery clusters, each battery cluster including several series-connected battery modules, and each battery module including several series-connected battery cells; it also includes a DC-DC step-down module, a first switching matrix module and a second switching matrix module;

[0048] like Figure 1 and 4 As shown, the DC-DC step-down module is connected to the positive terminal of each battery cluster simultaneously through its positive input terminal and to the negative terminal of each battery cluster simultaneously through its negative input terminal. It is connected to the positive input terminal of the first switch matrix module through its first positive output terminal and to the negative input terminal of the first switch matrix module through its first negative output terminal. It is also connected to the positive input terminal of the second switch matrix module through its second positive input terminal and to the negative input terminal of the second switch matrix module through its second negative output terminal. This module is used to step down the voltage signal input from the battery cluster and output a first voltage signal and a second voltage signal to the first switch matrix module and the second switch matrix module, respectively.

[0049] The first switch matrix module is connected to the positive terminal of each battery module through multiple first positive output terminals and to the negative terminal of each battery module through multiple first negative output terminals, which is used to control the output of the first voltage signal to charge the battery module with the lowest voltage among all battery clusters.

[0050] The second switch matrix module is connected to the positive terminal of each cell in each battery cluster through multiple second positive output terminals and to the negative terminal of each cell in each battery cluster through multiple second negative output terminals. It is used to control the output of the second voltage signal to charge the cell with the lowest voltage in each battery cluster.

[0051] During the battery cluster equalization process, the BMS collects the voltage of each battery module in each battery cluster, identifies the battery module with the lowest voltage, and outputs a first switch drive signal to the first switch matrix module. Simultaneously, the BMS collects the voltage of each cell in each battery cluster, identifies the cell with the lowest voltage, and outputs a second switch drive signal to the second switch matrix module. The first switch matrix module, responding to the first switch drive signal from the BMS, outputs voltage signals through its corresponding first positive and first negative output terminals to the battery module with the lowest voltage in all battery clusters, thus charging it. The second switch matrix module, responding to the second switch drive signal from the BMS, outputs voltage signals through its corresponding second positive and second negative output terminals to the cell with the lowest voltage within each battery cluster, thus charging it.

[0052] In this embodiment, the first voltage signal output of the DC-DC step-down module is controlled by the first switch matrix module to the battery module with the lowest voltage among all battery clusters, charging it and achieving voltage balance between battery modules in different battery clusters. Simultaneously, the second voltage signal output of the DC-DC step-down module is controlled by the second switch matrix module to the cell with the lowest voltage in each battery cluster, charging it and achieving voltage balance within the cell of each battery cluster. Therefore, this invention, by combining the first and second switch matrix modules, simultaneously performs voltage balancing between battery modules and within cells of different battery clusters, efficiently achieving voltage balance between cells in different battery clusters. This avoids the problem of increasingly poor cell consistency between different battery clusters in a multi-cluster battery pack system, thus improving the lifespan of the battery pack system.

[0053] In this plan, such as Figure 2 As shown, the first switch matrix module specifically includes a first input control unit and a first output control unit.

[0054] Specifically, the first input control unit is connected to the first positive output terminal of the DC-DC step-down module through its positive input terminal, to the first negative output terminal of the DC-DC step-down module through its negative input terminal, to the positive input terminal of the first output control unit through its positive output terminal, and to the negative input terminal of the first output control unit through its negative output terminal, and is used to control the input of the first voltage signal to the first switch matrix module.

[0055] The first output control unit is connected to the positive terminal of each battery module in each battery cluster through multiple first positive output terminals and to the negative terminal of each battery module through multiple first negative output terminals. It is used to control the first voltage signal output of the first switch matrix module to charge the battery module with the lowest voltage in all battery clusters.

[0056] Continue to refer to Figure 2 The second switch matrix module specifically includes a second input control unit and a second output control unit.

[0057] Specifically, the second input control unit is connected to the second positive output terminal of the DC-DC step-down module through its positive input terminal, to the second negative output terminal of the DC-DC step-down module through its negative input terminal, to the positive input terminal of the second output control unit through its positive output terminal, and to the negative input terminal of the second output control unit through its negative output terminal, and is used to control the input of the second voltage signal to the second switch matrix module.

[0058] The second output control unit is connected to the positive terminal of each cell in each battery cluster through multiple second positive output terminals and to the negative terminal of each cell through multiple second negative output terminals. It is used to control the second voltage signal output of the second switch matrix module to charge the cell with the lowest voltage in all battery clusters.

[0059] In this embodiment, the first switch matrix module, through the cooperation of the first input control unit and the first output control unit, controls the first switch matrix module to efficiently output a first voltage signal to the battery module requiring voltage equalization. The second switch matrix module, through the cooperation of the second input control unit and the second output control unit, controls the second switch matrix module to efficiently output a second voltage signal to the cell requiring voltage equalization. This enables rapid voltage equalization of cells between different battery clusters, significantly improving the equalization efficiency of the multi-cluster battery pack system.

[0060] Furthermore, in this plan, such as Figure 3 As shown, the first input control unit specifically includes a first positive input switch K3 and a first negative input switch K4.

[0061] Specifically, the first positive input switch K3 is connected between the first positive output terminal of the DC-DC step-down module and the positive input terminal of the first output control unit.

[0062] The first negative input switch K4 is connected between the first negative output terminal of the DC-DC step-down module and the negative input terminal of the first output control unit.

[0063] The first output control unit specifically includes n*n first positive output switches and n*n first negative output switches.

[0064] Specifically, each first positive output switch corresponds to a battery module and is connected between the positive output terminal of the first input control unit and the positive terminal of the battery module. Each first negative output switch corresponds to a battery module and is connected between the negative output terminal of the first input control unit and the negative terminal of the battery module.

[0065] Taking battery cluster 2 as an example, the first positive output switches are K3-21...K3-2(n-1) and K3-2n, corresponding one-to-one with battery modules M21...M2(n-1) and M2n, respectively. They are connected between the first positive input switch K3 and the positive terminal of the corresponding battery module, respectively. In response to the first switch drive signal, they work with the first positive input switch K3 to turn on or off the electrical connection between the first positive output terminal of the DC-DC step-down module and the positive terminal of the corresponding battery module. The first negative output switches are K4-21...K4-2(n-1) and K4-2n, corresponding one-to-one with battery modules M21...M2(n-1) and M2n, respectively. They are connected between the first negative input switch K3 and the negative terminal of the corresponding battery module, respectively. In response to the first switch drive signal, they work with the first negative input switch K4 to turn on or off the electrical connection between the first negative output terminal of the DC-DC step-down module and the negative terminal of the corresponding battery module.

[0066] If battery module M21 is the battery module with the lowest voltage among all battery clusters, when the first switch matrix module receives the first switch drive signal, it simultaneously controls the first positive input switch K3, the first negative input switch K4, the first positive output switch K3-21, and the first negative output switch K4-21 to close, so that the DC-DC step-down module charges battery module M21 until the voltage difference between battery module M21 and the battery module with the highest voltage among all battery clusters is less than the first preset difference value. At the same time, it controls the first positive input switch K3, the first negative input switch K4, the first positive output switch K3-21, and the first negative output switch K4-21 to open, and the charging ends.

[0067] Continue to refer to Figure 3 The second input control unit specifically includes a second positive input switch K1 and a second negative input switch K2.

[0068] Specifically, the second positive input switch K1 is connected between the second positive output terminal of the DC-DC step-down module and the positive input terminal of the second output control unit.

[0069] The second negative input switch K2 is connected between the second negative output terminal of the DC-DC step-down module and the negative input terminal of the second output control unit.

[0070] The second output control unit specifically includes n*n*s second positive output switches and n*n*s second negative output switches.

[0071] Specifically, each second positive output switch corresponds to one battery cell, connected between the positive output terminal of the second input control unit and the positive terminal of the battery cell. Each second negative output switch corresponds to one battery cell, connected between the negative output terminal of the second input control unit and the negative terminal of the battery cell.

[0072] like Figure 3 As shown, taking battery module M11 in battery cluster 1 as an example, the second positive output switches are K1-11, K1-12...K1-1s, corresponding one-to-one with battery cells D11, D12...D1s, respectively. They are connected between the second positive input switch K1 and the positive terminal of the corresponding battery cell, respectively. In response to the second switch drive signal, they work with the second positive input switch K1 to connect or disconnect the electrical connection between the second positive output terminal of the DC-DC step-down module and the positive terminal of the corresponding battery cell. The second negative output switches are K2-11, K2-12...K2-1s, corresponding one-to-one with battery cells D11, D12...D1s, respectively. They are connected between the second negative input switch K2 and the negative terminal of the corresponding battery cell, respectively. In response to the second switch drive signal, they work with the second negative input switch K2 to connect or disconnect the electrical connection between the second negative output terminal of the DC-DC step-down module and the negative terminal of the corresponding battery cell.

[0073] If cell D11 in battery module M11 is the battery module with the lowest voltage in battery cluster 1, when the second switch matrix module receives the second switch drive signal, it simultaneously controls the second positive input switch K1, the second negative input switch K2, the second positive output switch K1-11, and the second negative output switch K2-11 to close, so that the DC-DC step-down module charges cell D11 until the voltage difference between cell D11 and the cell with the highest voltage in battery cluster 1 is less than the second preset difference value. At the same time, it controls the second positive input switch K1, the second negative input switch K2, the second positive output switch K1-11, and the second negative output switch K2-11 to open, and the charging ends.

[0074] In this embodiment, a first positive output switch and a first negative output switch are provided in the first output control unit for each battery module. Responding to a first switch drive signal, the different output terminals of the first output control unit are precisely controlled to turn on and off, accurately outputting the first voltage signal from the first switch matrix module to the battery module requiring voltage equalization. Simultaneously, a second positive output switch and a second negative output switch are provided in the second output control unit for each cell. Responding to a second switch drive signal, the different output terminals of the second output control unit are precisely controlled to turn on and off, accurately outputting the second voltage signal from the second switch matrix module to the cell requiring voltage equalization. Therefore, this invention can simultaneously perform precise voltage equalization on battery modules between different battery clusters and on cells within the same battery cluster, greatly improving the stability of multi-cluster battery pack system equalization.

[0075] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance. In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connect" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

Claims

1. A dual-matrix balanced energy storage multi-cluster battery pack system, comprising a plurality of parallel battery clusters, each battery cluster comprising a plurality of series-connected battery modules, and each battery module comprising a plurality of series-connected battery cells; characterized in that, It also includes a DC-DC step-down module, a first switch matrix module, and a second switch matrix module; The DC-DC step-down module is connected to the positive terminal of each battery cluster through its positive input terminal and to the negative terminal of each battery cluster through its negative input terminal. It is connected to the positive input terminal of the first switch matrix module through its first positive output terminal and to the negative input terminal of the first switch matrix module through its first negative output terminal. It is connected to the positive input terminal of the second switch matrix module through its second positive output terminal and to the negative input terminal of the second switch matrix module through its second negative input terminal. It is used to step down the voltage signal input from the battery cluster and output a first voltage signal and a second voltage signal to the first switch matrix module and the second switch matrix module, respectively. The first switch matrix module is connected to the positive terminal of each battery module through multiple first positive output terminals and to the negative terminal of each battery module through multiple first negative output terminals, for controlling the output of the first voltage signal to charge the battery module with the lowest voltage among all the battery clusters; The second switch matrix module is connected to the positive terminal of each cell in each battery cluster through multiple second positive output terminals and to the negative terminal of each cell in each battery cluster through multiple second negative output terminals, for controlling the output of the second voltage signal to charge the cell with the lowest voltage in each battery cluster.

2. The dual-matrix balanced energy storage multi-cluster battery pack system according to claim 1, characterized in that, The first switch matrix module includes a first input control unit and a first output control unit; the second switch matrix module includes a second input control unit and a second output control unit. The first input control unit is connected to the first positive output terminal of the DC-DC step-down module through its positive input terminal, and to the first negative output terminal of the DC-DC step-down module through its negative input terminal. It is also connected to the positive input terminal of the first output control unit through its positive output terminal and to the negative input terminal of the first output control unit through its negative output terminal, and is used to control the input of the first voltage signal to the first switch matrix module. The first output control unit is connected to the positive terminal of each battery module in each battery cluster through multiple first positive output terminals and to the negative terminal of each battery module through multiple first negative output terminals. It is used to control the first voltage signal output of the first switch matrix module to charge the battery module with the lowest voltage in all battery clusters. The second input control unit is connected to the second positive output terminal of the DC-DC step-down module through its positive input terminal, and to the second negative output terminal of the DC-DC step-down module through its negative input terminal. It is also connected to the positive input terminal of the second output control unit through its positive output terminal and to the negative input terminal of the second output control unit through its negative output terminal, and is used to control the input of the second voltage signal to the second switch matrix module. The second output control unit is connected to the positive terminal of each cell in each battery cluster through multiple second positive output terminals and to the negative terminal of each cell through multiple second negative output terminals. It is used to control the second voltage signal output of the second switch matrix module to charge the cell with the lowest voltage in all battery clusters.

3. The dual-matrix balanced energy storage multi-cluster battery pack system according to claim 2, characterized in that, The first input control unit includes a first positive input switch and a first negative input switch; the second input control unit includes a second positive input switch and a second negative input switch. The first positive input switch is connected between the first positive output terminal of the DC-DC step-down module and the positive input terminal of the first output control unit; The first negative input switch is connected between the first negative output terminal of the DC-DC step-down module and the negative input terminal of the first output control unit; The second positive input switch is connected between the second positive output terminal of the DC-DC step-down module and the positive input terminal of the second output control unit; The second negative input switch is connected between the second negative output terminal of the DC-DC step-down module and the negative input terminal of the second output control unit.

4. The dual-matrix balanced energy storage multi-cluster battery pack system according to claim 2, characterized in that, The first output control unit includes a plurality of first positive output switches and a plurality of first negative output switches; the second output control unit includes a plurality of second positive output switches and a plurality of second negative output switches; Each of the first positive output switches corresponds to one of the battery modules and is connected between the positive output terminal of the first input control unit and the positive terminal of the battery module; Each of the first negative output switches corresponds to one of the battery modules and is connected between the negative output terminal of the first input control unit and the negative terminal of the battery module; Each of the second positive output switches corresponds to one of the battery cells and is connected between the positive output terminal of the second input control unit and the positive terminal of the battery cell; Each of the second negative output switches corresponds to one of the battery cells and is connected between the negative output terminal of the second input control unit and the negative terminal of the battery cell.

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