Battery body active self-balancing energy storage system

Abstract

This invention relates to a battery-based active self-balancing energy storage system, comprising an energy storage battery unit; the energy storage battery unit includes multiple battery sub-units distributed along a first direction, and each battery sub-unit includes at least one battery module; each battery module contains multiple individual cells distributed along a second direction, and the multiple individual cells in any battery module are correspondingly electrically connected to the multiple individual cells in adjacent battery modules; and the electrolyte chambers in any two adjacent individual cells are interconnected, allowing electrolyte in any individual cell to flow into the adjacent individual cells. The energy storage system of this invention achieves active self-balancing of the battery body through a series-parallel structure design of individual cells, thereby solving problems such as battery inconsistency, low charge / discharge capacity, low energy conversion efficiency, and short lifespan in energy storage systems.

Description

Technical Field

[0001] This invention relates to the field of energy storage battery technology, and in particular to an active self-balancing energy storage system for a battery body. Background Technology

[0002] Electrochemical energy storage converts electrical energy into chemical energy through a reversible chemical reaction in a battery, storing it and then converting the chemical energy back into electrical energy when needed. This conversion process mainly depends on the electrode materials and electrolyte properties, and is an important component of modern energy systems, widely used in power systems, transportation, communication base stations, data centers and other fields.

[0003] Due to the limited voltage and capacity of individual batteries, they need to be connected in series and parallel to meet the voltage and installed capacity requirements of energy storage systems in various application scenarios. This is especially true for large-scale energy storage systems with high voltage and large capacity, where higher requirements are placed on battery consistency to prevent issues such as bias current, premature capacity decay, and shortened lifespan. However, the materials involved in battery manufacturing cannot be completely identical. Furthermore, they are affected by fluctuations in manufacturing equipment, process parameters, and ambient temperature and humidity. Therefore, theoretically, it is impossible for batteries to be completely identical at the time of manufacture. Some batteries may even have potential manufacturing defects, such as micro-short circuits or poor welding. These problems will gradually deteriorate with the increase in battery usage time, widening the inconsistency between individual batteries. This leads to significant differences in internal resistance, voltage, capacity, charge / discharge characteristics, and individual cell temperature, increasing the difficulty of thermal and energy management of the entire energy storage system and further adversely affecting the charge / discharge capacity, energy utilization efficiency, and lifespan of the entire energy storage system.

[0004] Energy storage system management currently primarily employs two technologies to address battery inconsistencies: passive balancing and active balancing. Passive balancing is a technique that dissipates excess energy through resistor discharge to achieve uniform voltage and charge levels among individual cells within a battery pack. When the battery management system (BMS) detects that the voltage of a single cell is higher than that of other cells (exceeding a set threshold), balancing is initiated. The electrical energy of the high-voltage cell is released as heat through a parallel shunt resistor, reducing its voltage to match that of the other cells. This technology converts excess electrical energy into heat, resulting in energy waste and reduced system efficiency. Furthermore, the balancing current is small and the process is slow, making it difficult to meet the balancing requirements of large-capacity, high-efficiency energy storage systems. Active balancing is a technology that balances the voltage and charge of individual cells within a battery pack through energy transfer. The Battery Management System (BMS) monitors the cell status in real time and uses intermediate energy storage components (such as capacitors, inductors, and transformers) to transfer energy from high-voltage cells to low-voltage cells or redistribute energy. This technology offers relatively large balancing current and fast speed, significantly improving the energy utilization efficiency and cycle life of the battery pack. However, its balancing capability is limited for large-capacity individual cells. Furthermore, it requires additional DC-DC circuitry and control chips for real-time monitoring and dynamic adjustment of the balancing strategy, increasing the complexity of the BMS, making algorithm development difficult, and costly. In summary, both passive and active balancing technologies require external devices, limiting their balancing capabilities and effectiveness, while also increasing the difficulty and cost of system management. Summary of the Invention

[0005] This invention provides a battery-based active self-balancing energy storage system. By designing a series-parallel structure of individual batteries, the system achieves active self-balancing of the battery itself, thereby solving problems such as battery inconsistency, low charge and discharge capacity, low energy conversion efficiency, and short lifespan in energy storage systems.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An active self-balancing energy storage system for batteries includes energy storage battery units;

[0008] The aforementioned energy storage battery unit includes a plurality of battery sub-units distributed along a first direction, and the aforementioned battery sub-units include at least one battery module;

[0009] The aforementioned battery module contains a plurality of individual cells distributed along the second direction, and the plurality of individual cells in any of the aforementioned battery modules are electrically connected to the plurality of individual cells in the adjacent aforementioned battery modules.

[0010] Furthermore, the electrolyte chambers in any two adjacent cells are connected, so that the electrolyte in any one cell can flow into the adjacent cells.

[0011] Preferably, it also includes a charging / discharging device and a current detection and analysis unit;

[0012] Multiple individual cells in any of the aforementioned battery modules and multiple individual cells in adjacent battery modules are electrically connected to multiple first connection bars. Multiple individual cells in the two battery modules located at the two connection ends of the aforementioned energy storage battery unit are each connected to multiple second connection bars, and multiple second connection bars are each connected to a module busbar.

[0013] The aforementioned charging and discharging devices are respectively connected to the two aforementioned module busbars to charge and discharge the aforementioned energy storage battery units;

[0014] The aforementioned current detection and analysis unit is used to collect and analyze the current values ​​flowing through the first connecting bar and the second connecting bar in the aforementioned energy storage battery unit.

[0015] Preferably, the current detection and analysis unit includes a current detection device, a current detection signal transmission harness, and a current display screen;

[0016] The aforementioned current detection device is installed on the aforementioned first connecting bar and the aforementioned second connecting bar, and is used to detect and collect the current value flowing through the aforementioned first connecting bar and the aforementioned second connecting bar;

[0017] The aforementioned current detection device is connected to the aforementioned current display screen via the aforementioned current detection signal transmission harness, and is used to transmit the current value signals collected at each connection point to the aforementioned current display screen.

[0018] The aforementioned current display screen is used to centrally display the current values ​​collected from each connection point and compare them with the threshold range set within it to analyze whether a single cell has malfunctioned.

[0019] Preferably, the analysis process of the above-mentioned current display screen is as follows:

[0020] When the aforementioned energy storage battery unit is charging, the current flows through the aforementioned energy storage battery unit from the positive terminal to the negative terminal. If a certain current value collected by the aforementioned current display screen is greater than the threshold range, it is determined along the current direction that a short circuit has occurred inside the aforementioned single battery cell upstream of the corresponding connector, requiring maintenance. If a certain current value collected by the aforementioned current display screen is less than the threshold range, it is determined along the current direction that the internal resistance of the aforementioned single battery cell upstream of the corresponding connector has increased due to attenuation, requiring maintenance.

[0021] Alternatively, when the aforementioned current display screen's energy storage battery unit discharges, the current flows through the aforementioned current display screen's energy storage battery unit from the negative terminal to the positive terminal. If a certain current value collected by the aforementioned current display screen is less than a threshold range, then along the current direction, it is determined that a short circuit has occurred inside the aforementioned current display screen's single battery cell upstream of the corresponding connector, requiring maintenance. If a certain current value collected by the aforementioned current display screen is greater than a threshold range, then along the current direction, it is determined that the aforementioned single battery cell upstream of the corresponding connector has experienced internal attenuation leading to increased internal resistance, requiring maintenance.

[0022] Preferably, the aforementioned single-cell battery includes a casing and a positive electrode group, a negative electrode group, a positive electrode busbar, a negative electrode busbar, and an electrode group protective film disposed within the casing;

[0023] The multiple positive plates in the positive electrode group and the multiple negative plates in the negative electrode group are arranged alternately along the thickness direction of the single cell, and a separator is provided between two adjacent positive plates and negative plates.

[0024] The tabs of the multiple positive plates are electrically connected to the positive busbar, and the tabs of the multiple negative plates are connected to the negative busbar.

[0025] The aforementioned protective film covers the outside of the aforementioned positive electrode group and the aforementioned negative electrode group.

[0026] Preferably, the tabs of the positive electrode plate and the negative electrode plate are located at both ends of the single cell, and are electrically connected to the positive busbar and the negative busbar respectively through their respective tabs.

[0027] Preferably, the positive busbar is connected to a positive terminal, the negative busbar is connected to a negative terminal, and the positive terminal and the negative terminal are arranged diagonally on the single cell.

[0028] Preferably, the battery module includes a mounting housing, and the mounting housing has multiple mounting cavities, in which multiple individual batteries are correspondingly mounted.

[0029] Furthermore, each pair of adjacent mounting cavities has a partition wall with a connecting hole to allow the electrolyte cavities in the two adjacent individual cells to connect and form a flow channel for the electrolyte.

[0030] Preferably, the battery module in the battery sub-unit is configured as one, and a current detection device is provided on the first connection bar between two adjacent corresponding single cells along the first direction.

[0031] Alternatively, the battery modules within the aforementioned battery sub-unit may be configured as multiple, and two adjacent individual cells within the aforementioned battery sub-unit along the first direction may be connected by a third connecting row.

[0032] Preferably, in two corresponding single-cell batteries arranged adjacent to each other along the first direction, the positive or negative terminal of one of the single-cell batteries is arranged close to the positive or negative terminal of the other single-cell battery; and the positive and negative terminals on the same single-cell battery are arranged diagonally, and the positions of the positive and negative terminals on two adjacent single-cell batteries are opposite.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] 1. The individual cells within the battery module achieve self-balancing through the circulating shared electrolyte, maintaining the consistency of voltage among the individual cells within the module, thereby ensuring the charging and discharging efficiency and lifespan of the entire energy storage battery unit.

[0035] 2. Through real-time current detection and analysis, the inconsistency trend of individual cells or modules can be identified, and timely maintenance can be carried out. Individual cells or modules that are seriously outdated or faulty and have no further use value can be replaced in a timely manner through operation and maintenance to prevent the performance of the energy storage system from deteriorating. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the overall system in an embodiment of the present invention. Figure 1 ;

[0038] Figure 2 This is a schematic diagram of the overall system in an embodiment of the present invention. Figure 2 ;

[0039] Figure 3 This is a schematic diagram of the overall system in an embodiment of the present invention. Figure 3 ;

[0040] Figure 4 This is a schematic diagram of a single cell in an embodiment of the present invention. Figure 1 The positive extreme is located in the upper left and the negative extreme is located in the lower right;

[0041] Figure 5 Examples of embodiments of the present invention Figure 4 Schematic diagram of the current direction inside a single cell;

[0042] Figure 6This is a schematic diagram of a single cell in an embodiment of the present invention. Figure 1 The positive extreme is located at the bottom left, and the negative extreme is located at the top right.

[0043] Figure 7 This is a schematic diagram of a single cell in an embodiment of the present invention. Figure 2 .

[0044] Explanation of reference numerals in the attached figures:

[0045] 100. Energy storage battery unit; 1. Battery sub-unit; 2. Battery module; 3. Single cell; 31. Positive electrode group; 32. Negative electrode group; 33. Positive electrode busbar; 34. Negative electrode busbar; 35. Electrode group protective film; 36. Positive terminal; 37. Negative terminal; 38. Separator; 4. Mounting housing; 41. Partition wall; 42. Flow channel; 5. First connecting bar; 6. Second connecting bar; 7. Third connecting bar; 8. Module busbar;

[0046] 200. Charging and discharging equipment; 201. Cables;

[0047] 300. Current detection and analysis unit; 301. Current detection device; 302. Current detection signal transmission harness; 303. Current display screen. Detailed Implementation

[0048] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element 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 the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0050] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0051] This invention provides a battery-based active self-balancing energy storage system, such as... Figures 1-3 As shown, the system includes an energy storage battery unit 100, which comprises multiple battery sub-units 1 distributed along a first direction. These sub-units 1 are electrically connected. Each sub-unit 1 includes a battery module 2, and the battery module 2 contains multiple individual cells 3 distributed along a second direction. Each individual cell 3 is the smallest unit. In this embodiment, the electrolyte chambers within any two adjacent individual cells 3 are interconnected. That is, the electrolyte in the electrolyte chamber of any individual cell 3 can flow into adjacent individual cells 3 and into outermost individual cells 3. The electrolyte in an adjacent individual cell 3 can also flow into its adjacent electrolyte chamber. This ensures that the electrolyte chambers within all individual cells 3 in the entire battery module 2 are sequentially connected, forming an equalization chamber where electrolysis is achieved. Specifically, during charging and discharging, positively and negatively charged ions participating in the reaction migrate in the shared electrolyte. During charging, the charge from a high-voltage cell automatically transfers to a low-voltage cell via ion migration, achieving voltage clamping. During discharging, a low-voltage cell similarly accepts the charge from a high-voltage cell via ion migration, resulting in a voltage increase or a slower voltage decrease. This achieves self-balancing of individual cells 3, improving the voltage consistency of all individual cells 3 within the module. It realizes active self-balancing of the individual cells 3 within each energy storage module. Furthermore, the circulating shared electrolyte automatically achieves overall concentration balance, further maintaining chemical potential consistency. This solves the "weakest link" effect in the series-connected battery cluster caused by one or more lagging individual cells 3, ensuring the normal operation of the energy storage module. The first and second directions are as follows... Figure 1 As shown, the first direction is as follows Figure 1 The horizontal direction in the middle, the second direction as Figure 1 The vertical direction in the middle.

[0052] Furthermore, the connection relationship of individual cells 3 between multiple battery sub-units 1 is as follows: multiple individual cells 3 in any battery module 2 are electrically connected to multiple individual cells 3 in adjacent battery modules 2. Combined with the equalization cavity formed by multiple individual cells 3 in a single battery module 2, a strong series-weak parallel connection relationship is formed between adjacent battery modules 2. For ease of understanding, all individual cells 3 in the entire energy storage battery unit can be regarded as a combination of multiple rows of individual cells 3 (distributed along the first direction) and multiple columns of individual cells 3 (multiple battery modules 2 distributed along the second direction). Each row of individual cells 3 can be regarded as a series circuit, and multiple rows of cells can be regarded as multiple rows of series circuits. Therefore, multiple battery modules 2 can be regarded as series circuits. Combined with the multiple individual cells 3 in a single battery module 2 connected to form an equalization cavity, the multiple individual cells 3 in the battery module 2 are also connected in parallel. Therefore, battery modules 2 form a strong series-weak parallel connection. Along the direction of current, when a faulty cell 3 occurs in a battery module 2, causing the current to increase or decrease, due to the strong series connection, the current discharged to the corresponding normal cell will also increase or decrease. As charging and discharging proceed, its voltage will correspondingly enter a high voltage or low voltage state. Because the individual cells share electrolyte to form a weak parallel structure, when it is in a high voltage state, ion migration automatically transfers to the adjacent or outer low voltage cell, realizing current diversion and voltage clamping. When it is in a low voltage state, it will also receive the charge provided by the adjacent or outer high voltage cell through ion migration, realizing current inflow and voltage boost. Therefore, through the parallel structure, the charging and discharging of the corresponding normal cell in the next module is not affected, further improving the consistency of the entire energy storage system unit and ensuring that charging and discharging are not affected.

[0053] Furthermore, such as Figures 1-3 As shown, the energy storage system also includes a charging and discharging device 200 and a current detection and analysis unit 300. The charging and discharging device 200 is electrically connected to the energy storage battery unit 100 to charge and discharge the energy storage battery unit 100. The current detection and analysis unit 300 is used to detect the current inside the energy storage battery unit 100 and further analyze it to determine the inconsistency trend of the individual battery cells 3 and carry out timely maintenance.

[0054] Specifically, multiple individual cells within any battery module 2 and multiple individual cells within adjacent battery modules 2 are electrically connected to multiple first connection bars 5, which connect the battery modules 2 in series and conduct electricity. Multiple individual cells within the two battery modules 2 located at the two connection ends of the energy storage battery unit 100 are each connected to multiple second connection bars 6, which are all connected to module busbars 8. Module busbars 8 conduct electricity between the energy storage battery unit 100 and external electrical appliances. Specifically, the charging and discharging device 200 is connected to the two module busbars 8 respectively via cables 201 to charge and discharge the energy storage battery unit 100, making the energy storage battery unit 100 conduct electricity. Current flows through both the first connection bars 5 and the second connection bars 6. The charging and discharging device 200 can be a PCS, DC-DC, or hybrid inverter, or other charging and discharging devices 200; this is just an example and not a specific limitation. It is important to know that when the charging and discharging device 200 charges the energy storage battery unit 100, the current flows through the energy storage battery unit 100 from the positive terminal 36 to the negative terminal 37. When the energy storage battery unit 100 discharges, the current flows through the energy storage unit from the negative terminal 37 to the positive terminal 36.

[0055] The current detection and analysis unit 300 includes a current detection device 301, a current detection signal transmission harness 302, and a current display screen 303. The current detection devices 301 are installed on a first connection row 5 and a second connection row 6 between two adjacent battery modules 2 in different battery sub-units 1. Each current detection device 301 is connected to the current display screen 303 via the current detection signal transmission harness 302, thereby transmitting the current value signals collected from each connection row point to the current display screen 303. The current display screen 303 is used to centrally display the current values ​​collected from each connection row point, and then compares the current values ​​with a preset threshold range for further analysis. The current detection device 301 can be a current sensor.

[0056] Specifically, the current detection and analysis unit 300 sets a stable current value of I. This stable current value I is set by the designer based on the energy storage battery unit 100 and the individual battery cells 3. A threshold range is defined as 20% higher or lower than the set value I. Since the current detection device 301 can measure the current on the first connecting bar 5 and the second connecting bar 6 of the energy storage battery unit 100 during both charging and discharging, there are two scenarios: when the charging / discharging device 200 charges the energy storage battery unit 100, or when the energy storage battery unit 100 discharges. It is important to note that when the charging / discharging device 200 charges the energy storage battery unit 100, the current flows from the positive terminal 36 to the negative terminal 37. The current collected by the current detection device 301 is positive, which is I. The corresponding threshold range is set to 0.8I - 1.2I, when the energy storage battery unit 100 discharges, the current flows through the energy storage battery unit 100 from the negative terminal 37 to the positive terminal 36. If the current collected by the current detection device 301 is negative, then I is negative. The corresponding threshold range is set to -1.2I to -0.8I. The specific judgment is as follows:

[0057] 1. When the charging and discharging device 200 charges the energy storage battery unit 100, the current flows through the energy storage battery unit 100 from the positive terminal 36 to the negative terminal 37. The current detection device 301 collects the current. When the collected current value Icai is not within the threshold range, the current detection and analysis unit 300 issues an alarm. Specifically, when the current value Icai is greater than the maximum value of 1.2I within the threshold range, it is considered that the single cell 3 upstream of the corresponding connecting bar (first connecting bar or second connecting bar) has an internal short circuit, resulting in a decrease in internal resistance, and further repair is required. When the current value Icai is less than the minimum value of 0.8I within the threshold range, it is considered that the single cell 3 upstream of the corresponding connecting bar (first connecting bar or second connecting bar) has a defect or deterioration, resulting in an increase in internal resistance, and further repair or replacement is required.

[0058] 2. When the energy storage battery unit 100 discharges, the current flows through the energy storage battery unit 100 from the negative terminal 37 to the positive terminal 36. When the collected current value Icai is not within the threshold range, the current detection and analysis unit 300 issues an alarm. Specifically, when the current value Icai is less than the minimum value within the threshold range of -1.2I, it is considered that the single cell 3 upstream of the corresponding connecting bar (first connecting bar or second connecting bar) has an internal short circuit, resulting in a decrease in internal resistance, and further repair is required. When the current value Icai is greater than the minimum value within the threshold range of -0.8I, it is considered that the single cell 3 upstream of the corresponding connecting bar (first connecting bar or second connecting bar) has a defect or deterioration, resulting in an increase in internal resistance, and further repair or replacement is required.

[0059] It is important to note that the threshold range is set to 20% above and below the set value because if a single cell 3 fails, the current of the connecting bar corresponding to the adjacent single cell 3 will increase or decrease accordingly. However, this is not due to the failure, but due to the self-balancing within the single cell 3. Therefore, setting the threshold range slightly larger will make the analysis results more accurate.

[0060] In summary, based on the self-balancing of the 100 energy storage battery units, real-time current detection and analysis can identify inconsistencies in individual cells or battery modules, enabling timely maintenance and repair. Severely outdated or faulty cells or modules that are no longer usable can be replaced promptly through maintenance, preventing performance degradation of the energy storage system. Furthermore, the entire system does not use external devices or require complex BMS management and algorithm development, reducing costs and providing balancing capabilities and improving balancing effectiveness, thus enhancing the overall energy utilization efficiency and lifespan of the energy storage system.

[0061] Specifically, a single battery sub-unit 1 can be composed of one battery module 2 or multiple battery modules 2; specifically, such as Figure 1 and Figure 3 As shown, for a battery sub-unit 1 composed of a battery module 2, a current detection device 301 is provided on the first connection row 5 between two adjacent individual batteries 3 along the first direction; specifically, as shown... Figure 2 As shown, for an energy storage battery unit 100 composed of multiple battery modules 2, the corresponding individual cells 3 of two adjacent battery modules are connected by a third connecting bar 7, and there is no current detection device 301 on it. The current detection device 301 is set on the first connecting bar 5 between two adjacent battery sub-units 1 and the second connecting bar 6 on the outside. Therefore, when the current value on one of the first connecting bars 5 has a problem, the corresponding individual cells 3 in the battery sub-unit 1 upstream of the first connecting bar 5 need to be repaired and maintained in time. Individual cells 3 that are seriously outdated or faulty and have no further use value should be replaced in time through operation and maintenance.

[0062] Specifically, such as Figures 4-7As shown, the single-cell battery 3 includes a casing and a positive electrode group 31, a negative electrode group 32, a positive electrode busbar 33, a negative electrode busbar 34, and an electrode group protective film 35 disposed within the casing. The positive electrode group 31 includes multiple positive electrode plates, and the negative electrode group 32 includes multiple negative electrode plates. The multiple positive electrode plates and multiple negative electrode plates are arranged intersectingly along the thickness direction of the single-cell battery 3, and a separator 38 is disposed between two adjacent positive electrode plates and negative electrode plates to isolate the positive and negative electrodes, playing a crucial role in isolation and protection inside the battery. The electrode group protective film 35 covers the outside of the positive electrode group 31 and the negative electrode group 32 to prevent short circuits and protect the electrode plates during the installation of the electrode group into the battery casing. Both the positive and negative electrode plates have tabs, which are electrically connected to the positive busbar 33 and the negative busbar 34 respectively. Positive terminals 36 and negative terminals 37 are respectively provided on the positive busbar 33 and the negative busbar 34, and are electrically connected to the outside through the negative terminals 37 and the positive terminals 36.

[0063] Meanwhile, the positive tabs corresponding to the positive plate and the negative tabs corresponding to the negative plate are located at both ends of the single cell 3, so that the positive busbar 33 and the negative busbar 34 are also located at both ends of the single cell 3, in order to reduce the cost of the first connecting busbar 5, the second connecting busbar 6 and the third connecting busbar 7.

[0064] Furthermore, the positive terminal 36 and negative terminal 37 on the single cell 3 are arranged diagonally. Generally, the positive terminal 36 and negative terminal 37 of a storage battery (lithium battery, lead-acid battery or other storage battery) are located on the same surface. When the single cell 3 is charging or discharging, the current flows from the positive terminal 36 to the diagonally opposite negative terminal 37 or from the negative terminal 37 to the diagonally opposite positive terminal 36 inside the single cell 3, which can ensure that the current path inside each single cell 3 is consistent.

[0065] Specifically, the battery module 2 includes a mounting shell 4. Multiple partitions 41 are arranged inside the mounting shell 4 along a second direction, dividing the mounting shell 4 into multiple mounting cavities. Multiple individual batteries 3 are correspondingly installed in the mounting cavities. The partitions 41 are provided with connecting holes, allowing the electrolyte cavities within two adjacent individual batteries 3 to connect, forming electrolyte flow channels 42. It should be noted that the partitions 41 have a certain thickness to ensure the stable installation of the individual batteries 3 within the mounting cavities.

[0066] Specifically, since the positive terminal 36 of one individual battery 3 is connected to the negative terminal 37 of the other individual battery 3 via a connecting strip, generally, the height of each battery module 2 is the same, and the positive terminal 36 and negative terminal 37 of each individual battery 3 are located on its mounting surface. In order to shorten the length of the connecting strip used to connect the two individual batteries 3 between adjacent battery modules 2, making the structure between the two battery modules 2 more compact and the conduction path shorter, in this embodiment, the positive terminal 36 and negative terminal 37 on each individual battery 3 are arranged diagonally, so that along the first Two adjacent individual battery cells 3 are oriented in a specific direction, with positive and negative terminals respectively located at their closest ends. The positive terminals 36 and negative terminals 37 on the two adjacent individual battery cells 3 are positioned opposite each other. This results in the first connecting row 5, where the positive terminals 36 and negative terminals 37 of adjacent individual battery cells 3 are horizontally aligned and close together. For ease of understanding, consider the following example: Three battery modules 2 are distributed along the first direction, and each battery module 2 contains three individual battery cells 3 distributed along the second direction. For simplicity, the three battery modules 2 are referred to as the first battery module, the second battery module, and the third battery module, and the three individual battery cells 3 are referred to as the first battery module. The first, second, and third battery modules correspond to the three first batteries, three second batteries, and three third batteries within each module. Specifically, the connection of the first batteries is explained below. In the first battery module, the positive terminal 36 and negative terminal 37 of the first battery are located at the upper left and lower right, respectively. Similarly, in the second battery module, the positive terminal 36 and negative terminal 37 of the first battery are located at the lower left and upper right, and in the third battery module, they are located at the upper left and lower right. The connection of the positive and negative terminals 36 and 37 between adjacent first batteries is thus established. The projection of the connecting bar relative to the mounting surface of the individual battery 3 is either horizontally located at the lower part of the plane where the mounting surface is located, or horizontally located at the upper part of the plane where the mounting surface is located. It will not tilt from the lower right to the upper right or from the upper right to the lower right. This ensures that the connecting bar connecting the positive terminal 36 and the negative terminal 37 of two adjacent and corresponding individual batteries 3 is not tilted. The horizontal setting will be shorter, which will make the conduction path between the corresponding two individual batteries 3 shorter and more compact. This will further make the conduction path between two adjacent battery modules 2 shorter and the structure more compact. Moreover, this setting of the connecting bar also makes the entire energy storage battery unit 100 more aesthetically pleasing and orderly connected.

[0067] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A battery-based active self-balancing energy storage system, characterized in that, Including energy storage battery units; The energy storage battery unit includes a plurality of battery sub-units distributed along a first direction, and the battery sub-unit includes at least one battery module; The battery module contains a plurality of individual cells distributed along the second direction, and the plurality of individual cells in any battery module are electrically connected to the plurality of individual cells in the adjacent battery modules. Furthermore, the electrolyte chambers in any two adjacent individual cells within the battery module are interconnected, allowing the electrolyte in any individual cell to flow into the adjacent individual cell. When a single cell is in a high voltage state, ions migrate automatically to adjacent or further outer low voltage cells to achieve current shunting and voltage clamping. When a single cell is in a low voltage state, it receives the charge provided by adjacent or further outer high voltage cells through ion migration to achieve current inflow and voltage boost, and the charging and discharging of the next module's normal cells are not affected. The battery module includes a mounting shell with multiple mounting cavities inside. Multiple individual batteries are installed in the mounting cavities, and any two adjacent mounting cavities are separated by a partition wall with a connecting hole to allow the electrolyte cavities in two adjacent individual batteries to be connected and form a flow channel for the electrolyte.

2. The energy storage system according to claim 1, characterized in that, It also includes charging and discharging equipment and current detection and analysis units; Multiple individual cells within any of the battery modules and multiple individual cells within adjacent battery modules are electrically connected to multiple first connection bars. Multiple individual cells within the two battery modules located at the two connection ends of the energy storage battery unit are each connected to multiple second connection bars, and each of the multiple second connection bars is connected to a module busbar. The charging and discharging equipment is electrically connected to the two module busbars respectively to charge and discharge the energy storage battery unit; The current detection and analysis unit is used to collect and analyze the current values ​​flowing through the first connecting bar and the second connecting bar in the energy storage battery unit.

3. The energy storage system according to claim 2, characterized in that, The current detection and analysis unit includes a current detection device, a current detection signal transmission harness, and a current display screen. The current detection device is installed on the first connecting bar and the second connecting bar, and is used to detect and collect the current value flowing through the first connecting bar and the second connecting bar; The current detection device is connected to the current display screen through the current detection signal transmission harness, and is used to transmit the current value signals collected at each connection point to the current display screen. The current display screen is used to centrally display the current values ​​collected from each connection point and compare them with the threshold range set within it to analyze whether a single battery cell has malfunctioned.

4. The energy storage system according to claim 3, characterized in that, The analysis process of the current display screen is as follows: When the energy storage battery unit is charging, the current flows through the energy storage battery unit from the positive terminal to the negative terminal. If a certain current value collected by the current display screen is greater than a threshold range, it is determined along the current direction that a short circuit has occurred inside the single cell upstream of the corresponding connector, requiring maintenance. If a certain current value collected by the energy storage battery unit is less than a threshold range, it is determined along the current direction that the internal resistance of the single cell upstream of the corresponding connector has increased due to attenuation, requiring maintenance. Alternatively, when the energy storage battery unit discharges, the current flows through the energy storage battery unit from the negative terminal to the positive terminal. If a certain current value collected by the current display screen is less than a threshold range, it is determined along the current direction that a short circuit has occurred inside the single cell upstream of the corresponding connector, requiring maintenance. If a certain current value collected by the current display screen is greater than a threshold range, it is determined along the current direction that the internal resistance of the single cell upstream of the corresponding connector has increased due to attenuation, requiring maintenance.

5. The energy storage system according to claim 2, characterized in that, The single battery cell includes a casing and a positive electrode group, a negative electrode group, a positive electrode busbar, a negative electrode busbar, and an electrode group protective film disposed within the casing; The multiple positive plates in the positive electrode group and the multiple negative plates in the negative electrode group are staggered along the thickness direction of the single cell, and a separator is provided between two adjacent positive plates and negative plates. The tabs of the multiple positive plates are all electrically connected to the positive busbar, and the tabs of the multiple negative plates are all connected to the negative busbar; The protective film for the electrode group covers the outside of the positive electrode group and the negative electrode group.

6. The energy storage system according to claim 5, characterized in that, The tabs of the positive electrode plate and the negative electrode plate are located at both ends of the single cell, and are electrically connected to the positive busbar and the negative busbar respectively through their respective tabs.

7. The energy storage system according to claim 6, characterized in that, The positive busbar is connected to a positive terminal, and the negative busbar is connected to a negative terminal. The positive terminal and the negative terminal are arranged diagonally on the single cell.

8. The energy storage system according to claim 2, characterized in that, The battery module in the battery sub-unit is set as one, and a current detection device is provided on the first connection bar between two adjacent corresponding single cells along the first direction. Alternatively, the battery modules within the battery sub-unit may be configured as multiple, and two adjacent individual cells within the battery sub-unit along the first direction may be connected by a third connecting row.

9. The energy storage system according to claim 8, characterized in that, Two corresponding single cells are arranged adjacent to each other along a first direction, wherein the positive or negative terminal of one single cell is arranged close to the positive or negative terminal of the other single cell; and the positive and negative terminals on the same single cell are arranged diagonally, and the positive and negative terminals on two adjacent single cells are arranged in opposite positions.

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