energy storage device

Abstract

The application discloses an energy storage device, and relates to the technical field of energy storage. The energy storage device comprises a connecting row, a battery pack, a BMS plate and an inverter, and the connecting row is in positive electrode electrical connection with the battery cell of the battery pack, the BMS plate and the circuit board of the inverter, or the connecting row is in negative electrode electrical connection with the battery cell of the battery pack, the BMS plate and the circuit board of the inverter. The application can simplify the internal circuit connection of the portable energy storage device, reduce the number of wire harnesses, reduce the internal resistance of the system and improve the electrical connection reliability.

Description

Technical Field

[0001] This invention belongs to the field of energy storage technology, and particularly relates to an energy storage device. Background Technology

[0002] Portable energy storage technology, as an important component of modern distributed energy systems, has been widely applied in scenarios such as outdoor camping, emergency power supply, and home backup power. In existing technologies, portable energy storage devices generally adopt a discrete wiring harness connection scheme to achieve internal electrical interconnection: the total positive and total negative terminals of the battery pack are first connected to the input port of the battery management system (BMS) through independent wires or metal busbars (such as aluminum busbars), and then the output port of the BMS is led out through an additional wiring harness to establish an electrical connection with the control circuit board of the inverter, thereby forming multiple series current transmission paths.

[0003] However, this discrete wiring method has significant drawbacks: on the one hand, the large number of discrete wires, connectors, and terminals leads to a complex internal electrical structure and messy wiring; on the other hand, too many connection nodes not only occupy valuable internal space and increase assembly difficulty, but also easily cause problems such as local overheating, signal interference, or even connection failure due to uneven contact resistance or mechanical loosening. These factors severely restrict the compact and modular design of the overall structure, making it difficult to meet the development requirements of portable energy storage products for high energy density, high reliability, and miniaturization. Summary of the Invention

[0004] This invention provides an energy storage device that can solve the problems of complex structure and scattered electrical connection points caused by discrete wiring harnesses in existing portable energy storage products.

[0005] To address the aforementioned problems, embodiments of the present invention provide an energy storage device, including a connector, a battery pack, a BMS board, and an inverter. The connector is electrically connected to the positive terminals of the battery cells, the BMS board, and the inverter circuit board, respectively; or, the connector is electrically connected to the negative terminals of the battery cells, the BMS board, and the inverter circuit board, respectively.

[0006] In one optional embodiment, the connection bar is provided with a first connection part, a second connection part and a third connection part, and the first connection part, the second connection part and the third connection part are all electrically connected to each other. The first connection part is used to electrically connect with the battery cell, the second connection part is used to electrically connect with the BMS board, and the third connection part is used to electrically connect with the inverter circuit board.

[0007] In one optional embodiment, the connecting bar includes a first conductive plate, a second conductive plate, a third conductive plate, a first connecting plate, and a second connecting plate. The first conductive plate is connected to the second conductive plate through the first connecting plate, and the second conductive plate is connected to the third conductive plate through the second connecting plate. The first connecting part is located on the first conductive plate, the second connecting part is located on the second conductive plate, and the third connecting part is located on the third conductive plate.

[0008] In one alternative embodiment, the second conductive plate is higher than the first conductive plate, and the third conductive plate is higher than the second conductive plate.

[0009] In one optional embodiment, a buffer hole is provided at the connection between the first connecting plate and the first conductive plate, and / or, a buffer hole is provided at the connection between the first connecting plate and the second conductive plate.

[0010] In one alternative embodiment, the second connecting plate extends in a vertical wavy shape, the second conductive plate is connected to the lower end of the second connecting plate, and the third conductive plate is connected to the upper end of the second connecting plate.

[0011] In one optional embodiment, the first conductive plate, the second conductive plate, the third conductive plate, the first connecting plate, and the second connecting plate are all aluminum plates.

[0012] In one alternative embodiment, the first connection part is a welding part that can be welded to the terminal of the battery cell, and / or the second connection part is a connection hole through which a bolt can pass through the BMS board and the connection hole to be threadedly connected to a nut, and / or the third connection part is a connection hole through which a bolt can pass through the inverter's circuit board and the connection hole to be threadedly connected to a nut.

[0013] In one alternative embodiment, the battery pack, BMS board, and inverter circuit boards are stacked sequentially.

[0014] In one alternative embodiment, the battery pack includes battery cells and a support frame, both of which are detachably mounted on the support frame.

[0015] The energy storage device provided in this invention has at least the following advantages compared to existing technologies: The connecting busbar is electrically connected to the positive terminals of the battery cells, BMS board, and inverter circuit board of the battery pack, or the connecting busbar is electrically connected to the negative terminals of the battery cells, BMS board, and inverter circuit board of the battery pack, achieving integrated electrical connection between the battery cells, BMS board, and inverter circuit board. Based on this structure, after current flows from the battery cells into the connecting busbar, it can be synchronously transmitted to the BMS board and inverter circuit board without passing through discrete wiring harnesses, thereby integrating three key electrical nodes into a single current-carrying path. This design avoids the node dispersion problem caused by traditional multi-wiring harness connections, reduces the types of materials, lowers material costs, significantly simplifies the internal circuit layout, simplifies assembly, and improves error-proofing. The direct electrical connection of the connecting busbar to the battery cells, BMS board, and inverter circuit board of the battery pack increases the overcurrent capacity, reduces the internal resistance of previous wiring harness connections, improves the reliability of high-current transmission, and makes the internal structure of the energy storage device more concise and orderly. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the connection bar of an energy storage device provided in one embodiment of the present invention; Figure 2 This is another structural schematic diagram of the connection bar of the energy storage device provided in one embodiment of the present invention; Figure 3 This is a schematic diagram of the connection bar and the battery cell of the energy storage device provided in one embodiment of the present invention; Figure 4 This is a schematic diagram of the connection bar of the energy storage device provided in one embodiment of the present invention, connecting the battery cell and the BMS board; Figure 5 This is a schematic diagram of the connection bar of the energy storage device provided in one embodiment of the present invention, which is connected to the battery cell, BMS board and inverter. Figure 6 This is a schematic diagram of the connection bar of the energy storage device provided in one embodiment of the present invention, which is connected to the battery cell and the inverter.

[0018] The annotations in the attached figures are explained as follows: 100-Connecting bar, 110-First conductive plate, 111-First connecting part, 120-Second conductive plate, 121-Second connecting part, 130-Third conductive plate, 131-Third connecting part, 140-First connecting plate, 141-Buffer hole, 150-Second connecting plate, 200-Battery pack, 210-Battery cell, 220-Bracket, 300-BMS board, 400-Inverter. Detailed Implementation

[0019] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0020] In the description of this invention, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and 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, and therefore should not be construed as a limitation of the invention. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0021] 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.

[0022] like Figures 1 to 6 As shown, an embodiment of the present invention provides an energy storage device, which includes a connection bus 100, a battery pack 200, a BMS board 300, and an inverter 400. The connection bus 100 is electrically connected to the positive terminals of the battery cells 210 of the battery pack 200, the BMS board 300, and the circuit board of the inverter 400, respectively. Alternatively, the connection bus 100 is electrically connected to the negative terminals of the battery cells 210 of the battery pack 200, the BMS board 300, and the circuit board of the inverter 400, respectively.

[0023] Connector 100 is electrically connected to the positive terminals of the battery cells 210 of the battery pack 200, the BMS board 300, and the circuit board of the inverter 400, respectively; alternatively, connector 100 is electrically connected to the negative terminals of the battery cells 210 of the battery pack 200, the BMS board 300, and the circuit board of the inverter 400, respectively, thus achieving integrated electrical connection between the battery cells 210, the BMS board 300, and the circuit board of the inverter 400. Based on this structure, after current flows from the battery cells 210 into connector 100, it can be synchronously transmitted to the circuit boards of the BMS board 300 and the inverter 400 without passing through discrete wiring harnesses, thereby integrating three key electrical nodes into a single current conduction path. This design avoids the node dispersion problem caused by traditional multi-wiring harness connections, reduces the types of materials, lowers material costs, significantly simplifies the internal circuit layout, simplifies assembly, and improves error-proofing. The connecting bar 100 is directly connected to the battery cell 210 of the battery pack 200, the BMS board 300, and the circuit board of the inverter 400, which increases the overcurrent capacity, reduces the internal resistance of the previous wiring harness connection, improves the reliability of high current transmission, and makes the internal structure of the energy storage device more concise and orderly.

[0024] like Figures 1 to 2 As shown, the connection bar 100 is provided with a first connection part 111, a second connection part 121 and a third connection part 131, and the first connection part 111, the second connection part 121 and the third connection part 131 are all electrically connected to each other. The first connection part 111 is used to electrically connect to the cell 210 of the battery pack 200, the second connection part 121 is used to electrically connect to the BMS board 300, and the third connection part 131 is used to electrically connect to the circuit board of the inverter 400.

[0025] The first connection part 111 can refer to a conductive area disposed at one end of the connection bar 100. Its surface flatness and material conductivity are adapted to the welding process requirements of the battery cell 210 electrode post. It can form a low-resistance, high-reliability primary electrical connection with the battery cell 210 electrode post through laser spot welding, resistance welding, or ultrasonic welding. In this application, the function of this connection part is positioned as the starting access point of the charging and discharging main circuit. Its connection state with the battery cell 210 electrode post directly determines the initial conduction quality of the entire circuit. This connection part, the second connection part 121, and the third connection part 131 are electrically connected through the continuous conductive structure of the connection bar 100 body, and together they constitute the components of a single current trunk path. Through this cooperation, the current can flow from the battery cell 210 through the first connection part 111 into the connection bar 100 body, and be simultaneously distributed to the second connection part 121 and the third connection part 131, thereby supporting the BMS board 300 and the inverter 400 circuit board to work together under the same potential reference.

[0026] The battery pack 200 includes multiple cells 210 connected in series or in parallel. The positive or negative terminals of each cell 210 are led out together to form the total positive terminal (B+) or total negative terminal (B−) of the battery pack 200. The connector 100 is electrically connected to the total positive or total negative terminal through the first connector 111. When the connector 100 is used for the common positive terminal, the first connector 111 is a welded part that can be fixed to the surface of the cell 210 terminal by laser spot welding to form a low-resistance, highly reliable integrated connection. The structural dimensions, number and distribution of the welded part can be set according to the diameter of the cell 210 terminal and the current carrying capacity. This application embodiment does not impose any special limitations on this.

[0027] The second connection part 121 can refer to the conductive area located in the middle of the connection bar 100, which has a standard threaded hole or countersunk mounting hole to accommodate M4 to M6 bolts and nuts for fastening. In this application, the function of this connection part is positioned as a secondary electrical interface, used to receive the output / input signals of the power terminals of the BMS board 300. This connection part is electrically connected to the first connection part 111 through the conductive path of the connection bar 100 body, and is also electrically connected to the third connection part 131 through the same conductive path. There is no electrical isolation structure between the three to ensure a uniform potential. Through this cooperation, the BMS board 300 can monitor and regulate the current flowing through the entire main circuit of the connection bar 100 in real time, thereby achieving precise management of the battery module.

[0028] The BMS board 300 is provided with power input / output terminals, including positive (P+) and negative (P−) terminals. The connection bar 100 achieves a two-level electrical connection with the corresponding terminals of the BMS board 300 through the second connection part 121. The second connection part 121 is a connection hole, through which a bolt can pass and threadedly connect with a nut, thereby achieving a detachable, high-tightening mechanical-electrical composite connection. The diameter of the connection hole can be matched and set according to commonly used M4 to M6 bolt specifications, for example, a countersunk through hole of Φ4.2mm to Φ6.2mm. The distance between the edge of the hole and the edge of the conductive plate is not less than 1.5 times the thickness of the conductive plate to ensure structural strength and uniform current diffusion. This application embodiment does not impose any special limitations on this.

[0029] The third connection part 131 can refer to a conductive area disposed at the other end of the connection bar 100. Its structural form is the same as or different from that of the second connection part 121. For example, it can be a round connection hole with chamfers, an elliptical elongated hole, or an irregularly shaped clearance groove to adapt to the installation position and tolerance margin of the power terminals of the inverter 400 circuit board. The function of this connection part in this application is positioned as a three-level electrical interface for transmitting the main circuit current to the inverter 400 power module. This connection part, the first connection part 111, and the second connection part 121 are all on the same conductor, sharing the material, cross-sectional area, and heat conduction path. Through this cooperation, the inverter 400 can be directly powered by the battery module without additional boost / buck buffer, significantly reducing energy conversion loss and voltage fluctuation.

[0030] The inverter 400's circuit board has power input terminals, including positive (P+) and negative (P−) terminals. The connector 100 achieves a three-level electrical connection with the corresponding terminals of the inverter 400's circuit board through the third connector 131. The third connector 131 is also a connector hole, through which a bolt can pass and threadedly connect with a nut. The position, number, and arrangement of the connector holes correspond one-to-one with the PCB terminal pads of the inverter 400, with a ≥0.3mm assembly tolerance allowance reserved to accommodate interface differences between inverter 400 modules from different manufacturers. In this embodiment, the third connector 131 can share the same conductive plate with the second connector 121, or it can be located on different conductive plate segments. The specific arrangement depends on the overall stacking height and wiring space constraints.

[0031] The function of the connector 100 in the energy storage device is as follows: During charging, the current from the inverter 400 (as the rectifier / charging input terminal) is introduced through the third connector 131, supplied to the BMS board 300 for sampling and control circuit power supply through the second connector 121, and finally delivered to the battery pack 200 for energy storage through the first connector 111; During discharging, the current path is reversed, that is, the current is output from the battery pack 200 through the first connector 111, supplied to the BMS board 300 for working power and status monitoring signal circuit through the second connector 121, and then delivered to the inverter 400 for DC / AC conversion output through the third connector 131; Thus, the connector 100 forms a single, continuous, low-impedance main current channel in both positive and negative common port configurations, avoiding the superposition of contact nodes and impedance accumulation introduced by multiple wire harnesses.

[0032] Specifically, the connector 100, battery pack 200, BMS board 300, and inverter 400 are integrated in a stacked manner inside the whole unit: the battery pack 200 is located at the bottom, the BMS board 300 is in the middle, and the inverter 400 is located at the top; the three are stacked vertically, and their interface planes correspond to the installation heights of the first connection part 111, the second connection part 121, and the third connection part 131 of the connector 100, respectively; the connector 100 has a stepped or Z-shaped bending structure to adapt to the height difference of the installation reference surface of different components. The connector 100 can achieve natural docking through the step-by-step lifting of the first conductive plate 110, the second conductive plate 120, and the third conductive plate 130, without the need for additional transfer harnesses or transition copper busbars.

[0033] The core innovation of this application lies in the construction of a rigid common port connection architecture that uses a single conductor as a carrier and covers the entire 400-link from battery to BMS to inverter. This architecture, through spatial layout reconstruction and interface function reuse, compresses the connection task that originally required multiple sets of independent wires into two structural components (positive row + negative row) without increasing the number of electrical nodes, thus realizing the physical unification of electrical paths and the hierarchical convergence of connection logic.

[0034] The working process and principle of this application are as follows: When the energy storage system is in the charging state, the external power supply current is rectified by the inverter 400 and injected into the connection bus 100 through the third connection part 131. It is then conducted through the connection bus 100 to the second connection part 121 for sampling and protection control by the BMS board 300, and finally reaches the first connection part 111 and flows into the battery cell 210 to complete energy storage. When the system is in the discharging state, the current released by the battery cell 210 enters the connection bus 100 through the first connection part 111, and is simultaneously supplied to the second connection part 121 to support the operation of the BMS board 300. It is then output to the inverter 400 through the third connection part 131 for DC / AC conversion. Throughout the process, the three connection parts are always in an equipotential state, and the current distribution is naturally determined by the load impedance of each branch, without the need for additional current sharing devices.

[0035] As an optional embodiment, the solution of this application is specifically implemented as follows: During the assembly of the portable energy storage device, firstly, two independent aluminum busbars are installed in the preset slots of the bracket 220 as the total positive common busbar and the total negative common busbar, respectively; then, the total positive (B+) and total negative (B−) of the battery pack 200 are welded to the first connection part 111 of the corresponding aluminum busbar using laser spot welding; next, the BMS board 300 is pressed down along the guide post, so that its P+ and P− terminals are aligned with the connection holes of the second connection part 121 of the aluminum busbar, and M5 bolts are inserted and tightened to a torque of 5 N·m; finally, the inverter 400 module is snapped onto the top, so that its power terminals are coaxially aligned with the connection holes of the third connection part 131 of the aluminum busbar, and M4 bolts are inserted and tightened to a torque of 3.5 N·m; after the assembly is completed, the whole device has complete charging and discharging common port capability, and all main current paths flow through the same aluminum busbar, without branches, switching, or plug-in interfaces.

[0036] Through the above technical solution, this application achieves the following: Since the connecting busbar 100 uniformly carries the positive or negative current paths of the battery pack 200, BMS board 300, and inverter 400, it eliminates the redundant connection nodes between multiple wire harnesses in traditional solutions, reducing the total system contact resistance; since the three connection parts share the same potential reference, it avoids BMS misjudgment and abnormal shutdown of the inverter 400 caused by multi-path potential drift; and since the connecting busbar 100 adopts an integrated conductive structure and uses a dual connection process of laser welding and bolt fastening, it improves thermal stability and vibration resistance under high current conditions. The system is designed to be robust and reliable. Because the interfaces of the three components are individually bound to the 100-type connector structure, it achieves both physical and electrical error prevention during assembly. The highly concentrated current path and controllable cross-section improve electromagnetic radiation distribution, contributing to overall EMC performance compliance. Eliminating redundant wiring harnesses and connectors saves internal space, providing structural margin for battery module expansion and heat dissipation optimization. Since this common-port structure does not depend on a specific BMS or inverter model, but only requires matching terminal positions and current carrying capacity, it can be reused in various product forms such as portable energy storage, balcony energy storage, and integrated home energy storage systems.

[0037] In yet another embodiment, such as Figure 1 and Figure 2 As shown, this application also provides a connecting strip 100 including a first conductive plate 110, a second conductive plate 120, a third conductive plate 130, a first connecting plate 140, and a second connecting plate 150. The first conductive plate 110 is connected to the second conductive plate 120 through the first connecting plate 140, and the second conductive plate 120 is connected to the third conductive plate 130 through the second connecting plate 150. The first connecting part 111 is located on the first conductive plate 110, the second connecting part 121 is located on the second conductive plate 120, and the third connecting part 131 is located on the third conductive plate 130.

[0038] The first conductive plate 110 is a flat conductive structure used to carry and conduct current from the battery cell 210. A first connecting portion 111 is provided on it, which is a structural area for electrical connection with the battery cell 210 terminal, specifically a laser spot welding area or a press-fit contact surface. The first conductive plate 110 serves as the main bearing for the current input terminal in the overall connection array 100, with its plane facing the battery module and maintaining surface or point contact with the battery cell 210 terminal to reduce contact resistance. The first conductive plate 110 and the first connecting plate 140 are connected by riveting, laser welding, or integral stamping to ensure continuous electrical path and stable mechanical connection. In this application, the first conductive plate 110 transmits current to the second conductive plate 120 through the first connecting plate 140, forming a primary current conduction path that serves as the initial current introduction function for the system's main charging and discharging circuit.

[0039] The second conductive plate 120 is a flat conductive structure positioned higher than the first conductive plate 110. It carries and conducts the current transmitted through the first connecting plate 140. A second connecting portion 121 is provided on it, which is a structural area for electrical connection with the BMS board 300. Specifically, it is a circular or oblong connecting hole on the plate. A bolt can pass through the BMS board 300 and the connecting hole and then be locked with a nut to establish a low-resistance, detachable electrical connection. The connection end of the second conductive plate 120 with the first connecting plate 140 forms a first-level height transition, and the connection end with the second connecting plate 150 forms a second-level height transition. The two transitions together adapt to the vertical installation tolerances generated when the battery module and the BMS board 300 are stacked inside the energy storage device. The second conductive plate 120 continues to conduct the current to the third conductive plate 130 through the second connecting plate 150, forming a two-level current conduction path. It plays a role in current conduction and spatial coordination in the overall structure.

[0040] The third conductive plate 130 is a flat conductive structure positioned higher than the second conductive plate 120. It carries and conducts the current transmitted via the second connecting plate 150. A third connecting part 131 is provided on it, which is a structural area for electrical connection with the circuit board of the inverter 400. Specifically, it is a connecting hole opened on the plate body. A bolt can pass through the inverter 400 circuit board and the connecting hole and then be locked with a nut to establish a stable and maintainable electrical connection. The third conductive plate 130 is spatially positioned corresponding to the power terminal position of the inverter 400. Its plane faces the inverter 400 side and forms a parallel fit or a micro-gap fit with the inverter 400 circuit board. The third conductive plate 130 serves as the main body carrying the current output terminal and, together with the second connecting plate 150, completes the height adaptation and electrical lead-out of the inverter 400 side interface.

[0041] The first connecting plate 140 is a strip-shaped metal plate, with its two ends fixedly connected to the first conductive plate 110 and the second conductive plate 120, respectively, to provide a flexible transition and stress relief space between the two. The first connecting plate 140 is a straight, L-shaped, or curved bent structure, and its length and bending angle can be set according to the actual assembly gap. In this application, the first connecting plate 140 not only realizes the longitudinal conduction of current, but also absorbs the difference in thermal expansion and contraction and the cumulative assembly tolerance between the first conductive plate 110 and the second conductive plate 120 through its own elastic deformation, preventing the weld cracking or loosening of the connection caused by rigid connection. The connection relationship between the first connecting plate 140 and the first conductive plate 110 and the second conductive plate 120 is as follows: the current enters the body of the first connecting plate 140 from the first conductive plate 110 through the interface, is conducted along its extension direction to the connection interface with the second conductive plate 120, and then injected into the second conductive plate 120. This connection path constitutes a complete, low-inductance, and low-resistance physical conductive link.

[0042] The second connecting plate 150 is a strip-shaped metal plate, with its two ends fixedly connected to the second conductive plate 120 and the third conductive plate 130, respectively, to provide vertical extension and dynamic buffering between the two. The second connecting plate 150 has a vertical straight, Z-shaped, S-shaped, or wavy structure. When a wavy structure is adopted, it undulates periodically along the vertical direction, which can further improve the axial compression / tension redundancy and enhance the ability to withstand vibration loads. The connection end of the second connecting plate 150 with the second conductive plate 120 is located at its lower end, and the connection end with the third conductive plate 130 is located at its upper end, forming a clear hierarchical guiding relationship between the two in the vertical direction. In this application, the second connecting plate 150 undertakes the dual functions of secondary height transition and multi-dimensional stress buffering, and its structural form directly affects the spatial positioning accuracy and long-term connection stability of the third conductive plate 130.

[0043] Specifically, the first conductive plate 110, the second conductive plate 120, and the third conductive plate 130 are arranged in a stepped manner in the vertical direction. The first connecting plate 140 connects the first conductive plate 110 and the second conductive plate 120 to achieve the first level of height transition. The second connecting plate 150 connects the second conductive plate 120 and the third conductive plate 130 to achieve the second level of height transition. The two levels of transition together constitute a three-dimensional spatial layout in which the battery pack 200, BMS board 300, and inverter 400 are stacked in sequence. Current flows from the cell 210 into the first conductive plate 110 through the first connecting part 111, is conducted through the first connecting plate 140 to the second conductive plate 120, and then through the second connecting plate 150 to the third conductive plate 130. Finally, it is output to the inverter 400 through the third connecting part 131. The entire path is continuous, the cross-section is sufficient, the direction is controllable, there are no branches or junction nodes, which significantly reduces the risk of main circuit impedance and electromagnetic interference.

[0044] As an optional embodiment, the specific implementation of the solution in this application is as follows: During the assembly of the portable energy storage device, the battery module is first fixed on the bracket 220 with its positive terminal exposed upwards; the first conductive plate 110 is placed above the terminal and welded in the first connection part 111 area by laser spot welding to form a solid primary electrical connection; then the BMS board 300 is installed above the battery module, with the P+ terminal of the BMS board 300 aligned with the second connection part 121 on the second conductive plate 120, bolts are inserted and nuts are tightened to complete the secondary electrical connection; finally, the inverter 400 is installed above the BMS board 300, with the P+ terminal of the inverter 400 circuit board aligned with the third connection part 131 on the third conductive plate 130, bolts are inserted and nuts are tightened to complete the tertiary electrical connection; after assembly, the entire connection bar 100 forms a stepped three-dimensional conductive frame, with each conductive plate arranged horizontally and each connection plate transitioning vertically, resulting in a compact overall structure, clear hierarchy, and stress dispersion, meeting the long-term vibration reliability requirements under IP67 protection level.

[0045] Through the above technical solution, since the first conductive plate 110, the second conductive plate 120 and the third conductive plate 130 are connected in segments by the first connecting plate 140 and the second connecting plate 150 and raised step by step, it can adapt to the physical layout of the battery pack 200, the BMS board 300 and the inverter 400 stacked in sequence in the energy storage device; since each conductive plate independently carries the corresponding connection part and the connecting plate provides a flexible transition, it avoids connection failure caused by thermal deformation or assembly deviation of a single long aluminum busbar; since all conductive components are metal plate structures and the connection methods include welding and bolt fastening, it takes into account both high current carrying capacity and maintainability; since the conductive path is a unidirectional serial structure without parallel current splitting or cross wiring, the main circuit impedance consistency is high and the system voltage fluctuation is small.

[0046] In this embodiment, as Figure 1 and Figure 2As shown, the second conductive plate 120 is higher than the first conductive plate 110, and the third conductive plate 130 is higher than the second conductive plate 120. Since the second conductive plate 120 is higher than the first conductive plate 110, the first connecting part 111 and the second connecting part 121 are arranged in layers in the vertical direction, so that the connecting bar 100 can simultaneously adapt to the spatial interface position of the bottom cell 210 and the middle layer BMS board 300. Since the third conductive plate 130 is higher than the second conductive plate 120, the second connecting part 121 and the third connecting part 131 are also arranged in layers, so that the connecting bar 100 can further adapt to the interface position of the top layer inverter 400 circuit board. Thus, in the application scenario where the battery pack 200, BMS board 300 and inverter 400 circuit board are arranged in a stacked manner, the common port electrical connection of the three under the same main circuit can be achieved by using only the stepped height layout of a single connecting bar 100. This avoids the problems of path redundancy, multiple contact points and assembly complexity caused by traditional discrete connections, and improves the system integration, connection reliability and assembly efficiency.

[0047] In one alternative implementation, such as Figure 1 As shown, a buffer hole 141 is provided at the connection between the first connecting plate 140 and the first conductive plate 110, and / or, a buffer hole 141 is provided at the connection between the first connecting plate 140 and the second conductive plate 120.

[0048] The buffer hole 141 can refer to a through hole opened in the connection area between the first connecting plate 140 and the first conductive plate 110, or in the connection area between the first connecting plate 140 and the second conductive plate 120. Its function is to locally weaken the structural rigidity of the connection area and form a stress release transition zone. The buffer hole 141 can be circular, elliptical, waist-shaped or rectangular. Its shape, size and number can be adapted and set according to the actual assembly tolerance, the difference in thermal expansion coefficient and the expected vibration load. For example, the diameter can be selected in the range of Φ1.5mm to Φ4.0mm. This application embodiment does not make any special limitation in this regard.

[0049] When the height between the battery cell 210 and the BMS board 300 deviates due to installation errors, the buffer hole 141 locally weakens the structural rigidity of the connection area, so that the height difference between the first conductive plate 110 and the second conductive plate 120 can be adapted to the height between the battery cell 210 and the BMS board 300, thereby ensuring the electrical connection between the first conductive plate 110 and the battery cell 210 and the electrical connection between the second conductive plate 120 and the BMS board 300.

[0050] In one alternative implementation, such as Figure 1 and Figure 2 As shown, the second connecting plate 150 extends vertically in a wavy shape, the second conductive plate 120 is connected to the lower end of the second connecting plate 150, and the third conductive plate 130 is connected to the upper end of the second connecting plate 150.

[0051] The second connecting plate 150 extends vertically in a wavy shape, which can refer to the connecting plate having a continuously undulating sine wave, cosine wave, or sawtooth-like periodic curved surface structure in the vertical direction, with its outline having multiple alternating peaks and troughs in the vertical plane; the wavy structure can be obtained by stamping, bending, or integral casting, and its wavelength, amplitude, and radius of curvature can be set according to the actual assembly height difference, expected elastic deformation, and current carrying requirements, which are not specifically limited in this embodiment; the structure provides axial compression and tensile elasticity in the vertical direction without significantly reducing the conductive cross-sectional area, and is used to absorb the relative displacement between the second conductive plate 120 and the third conductive plate 130 caused by installation tolerances, thermal expansion differences, or operating vibrations.

[0052] The corrugated extension structure of the second connecting plate 150 allows for an initial height deviation between the second conductive plate 120 and the third conductive plate 130 during assembly, and accommodates relative displacement caused by temperature changes during system operation; the coefficient of thermal expansion of the aluminum conductive plate is approximately 23 × 10⁻⁻⁴. 6 / ℃, when the temperature rises to 40℃, the elongation of a 100mm conductor is 0.092mm, and the wave structure can absorb this magnitude of displacement; when subjected to external vibration excitation, its natural frequency avoids the typical operating frequency band of energy storage devices (5–200Hz), avoiding the resonance amplification effect; at the same time, the wave-shaped profile maintains the continuity of the overall conductive path without introducing additional contact interfaces, ensuring that the current path resistance does not increase due to the structural flexibility.

[0053] As an optional embodiment, the specific implementation of the solution in this application is as follows: During the assembly stage of the energy storage device, the BMS board 300 is first fixed at a specified height position on the bracket 220, and then the inverter 400 circuit board is stacked on top of the BMS board 300 while maintaining a preset distance; at this time, due to the cumulative tolerance of processing and assembly, there is a height difference of 0.8mm between the actual mounting planes of the second conductive plate 120 and the third conductive plate 130; the prefabricated corrugated structure of the second connecting plate 150 is placed between the two, so that its lower end is laser-spot welded to the second conductive plate 120 and its upper end is bolted to the third conductive plate 130; during the locking process, the corrugated structure undergoes micro-elastic compression, automatically compensating for the height difference, and finally the three form a stable, low-resistance, stress-free electrical connection state.

[0054] Through the above technical solution, the second connecting plate 150 adopts a vertical wave-shaped extension structure, which can provide longitudinal elastic compensation between the second conductive plate 120 and the third conductive plate 130. The second conductive plate 120 is connected to the lower end of the second connecting plate 150 and the third conductive plate 130 is connected to the upper end of the second connecting plate 150, thus constructing a clear force input-elastic buffer-force output path. This solves the problem of stress concentration in rigid connection caused by the height difference between the second conductive plate 120 and the third conductive plate 130, and improves the structural robustness and electrical connection reliability of the connecting bar 100 under long-term operation and vibration conditions.

[0055] In this embodiment, the first conductive plate 110, the second conductive plate 120, the third conductive plate 130, the first connecting plate 140, and the second connecting plate 150 are all aluminum plates. Since all conductive and connecting components use aluminum plates of the same material, the risk of contact corrosion caused by electrochemical potential differences between different metals is eliminated. Because aluminum has good ductility and stamping formability, it supports the simultaneous processing of buffer holes 141 and corrugated structures on the first connecting plate 140 and the second connecting plate 150, without the need for additional assembly processes or auxiliary elastic elements. Since the density of aluminum is only about 30% of that of copper, the overall weight is significantly reduced while maintaining the same current carrying capacity, improving the mobility and lightweight structure of portable energy storage products.

[0056] In this embodiment, the first connecting part 111 is a welding part, which can be welded to the terminal of the battery cell 210, and / or, the second connecting part 121 is a connecting hole, through which a bolt can pass through the BMS board 300 and the connecting hole to be threadedly connected to a nut, and / or, the third connecting part 131 is a connecting hole, through which a bolt can pass through the circuit board of the inverter 400 and the connecting hole to be threadedly connected to a nut.

[0057] Since the first connection part 111 is welded and directly welded to the terminal of the cell 210, the interface bonding strength and current carrying stability of the cell 210 side connection are improved. Since the second connection part 121 and the third connection part 131 are respectively set as connection holes for adapter bolt fastening, independent disassembly and assembly and module replacement of the BMS board 300 and the inverter 400 circuit board are supported. Since the three connection parts are integrated on different conductive plates of the same connection bar 100 and arranged in an orderly manner according to the current flow direction and spatial height, the electrical performance is guaranteed while achieving the unity of structural error prevention, assembly fault tolerance and maintenance convenience.

[0058] One possible implementation is, such as Figures 3 to 6 As shown, the battery pack 200 includes battery cells 210 and a bracket 220. Both the battery cells 210 and the BMS board 300 can be detachably installed on the bracket 220.

[0059] The bracket 220 is a rigid load-bearing structural component and can be a modular mounting frame made of aluminum alloy or engineering plastic. The function of the bracket 220 is to provide a unified mechanical reference surface and a resettable assembly interface for the various functional units inside the battery pack 200. Its structure does not participate in current conduction and only provides mechanical support and spatial constraint. The bracket 220 and the cell 210 are detachably connected by a snap-fit ​​and screw-assisted locking method. The snap-fit ​​structure is used for quick alignment and initial fixation, while the screws are used for final tightening and to ensure connection stability under vibration conditions. The bracket 220 and the BMS board 300 are detachably connected by bolts.

[0060] The battery cell 210 can be a cylindrical lithium-ion battery cell 210, a square aluminum-cased battery cell 210, or a soft-pack battery cell 210. There is no irreversible connection method such as adhesive or welding between the battery cell 210 and the bracket 220. All fastening adopts a mechanical structure that can be repeatedly disassembled and assembled.

[0061] Through the above technical solution, because the bracket 220 is equipped with standardized positioning grooves, guide ribs, and a resettable locking structure, the battery cell 210 and the BMS board 300 can be independently, quickly, and repeatedly disassembled and installed without damaging the electrical connection bar 100. Since the bracket 220 serves as a shared bearing platform to uniformly constrain the spatial position of the battery cell 210 and the BMS board 300, the connection bar 100 can be accurately aligned to each connection part without secondary adjustment after installation, avoiding assembly stress or poor contact caused by component misalignment. Since both the battery cell 210 and the BMS board 300 adopt a mechanical quick-release structure, the on-site maintainability and modular configuration capability of the energy storage device are significantly improved, supporting the mixed replacement of battery cells 210 of different capacities and the non-destructive upgrade of BMS function versions.

[0062] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. An energy storage device, characterized in that, The device includes a connector, a battery pack, a BMS board, and an inverter. The connector is electrically connected to the positive terminal of the battery cell, the BMS board, and the inverter circuit board, respectively. Alternatively, the connector is electrically connected to the negative terminal of the battery cell, the BMS board, and the inverter circuit board, respectively. The connection bar is provided with a first connection part, a second connection part and a third connection part, and the first connection part, the second connection part and the third connection part are all electrically connected to each other. The first connection part is used to electrically connect to the battery cell of the battery pack, the second connection part is used to electrically connect to the BMS board, and the third connection part is used to electrically connect to the circuit board of the inverter. The connecting plate includes a first conductive plate, a second conductive plate, a third conductive plate, a first connecting plate, and a second connecting plate. The first conductive plate is connected to the second conductive plate through the first connecting plate, and the second conductive plate is connected to the third conductive plate through the second connecting plate. The first connecting part is located on the first conductive plate, the second connecting part is located on the second conductive plate, and the third connecting part is located on the third conductive plate. The second conductive plate is higher than the first conductive plate, and the third conductive plate is higher than the second conductive plate; A buffer hole is provided at the connection between the first connecting plate and the first conductive plate, and / or, a buffer hole is provided at the connection between the first connecting plate and the second conductive plate; The second connecting plate extends vertically in a wavy shape, the second conductive plate is connected to the lower end of the second connecting plate, and the third conductive plate is connected to the upper end of the second connecting plate.

2. The energy storage device according to claim 1, characterized in that, The first conductive plate, the second conductive plate, the third conductive plate, the first connecting plate, and the second connecting plate are all aluminum plates.

3. The energy storage device according to claim 1, characterized in that, The first connection part is a welding part, which can be welded to the terminal of the battery cell, and / or the second connection part is a connection hole, through which a bolt can pass and be threaded to a nut, and / or the third connection part is a connection hole, through which a bolt can pass and be threaded to a nut, and / or the third connection part is a connection hole, through which a bolt can pass and be threaded to a nut, and the circuit board of the inverter.

4. The energy storage device according to claim 1, characterized in that, The battery pack, the BMS board, and the inverter circuit board are stacked sequentially.

5. The energy storage device according to claim 1, characterized in that, The battery pack includes battery cells and a support frame, and both the battery cells and the BMS board can be detachably installed on the support frame.

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