High-strength and high-integration power battery system

Abstract

The invention discloses a high-strength and high-integration power battery system. The system comprises a plurality of battery box bodies; wherein the plurality of battery box bodies are stacked and fixed in the height direction to form a battery system main body, and a cover body is arranged at the top of the battery system main body; a supporting structural member is arranged at the corner of the side wall and / or the side wall of the battery system main body; and a BDU is arranged on the side surface of the battery system main body. The high-strength and high-integration power battery system provided by the invention has the advantages of high strength, high reliability, excellent anti-loosening performance, high integration level, low cost, convenience in space optimization and maintenance and high function integration level.

Description

Technical Field

[0001] This invention relates to a high-strength, highly integrated power battery system, belonging to the field of power battery technology. Background Technology

[0002] As the energy crisis worsens, construction machinery is accelerating its transformation from fuel-powered to electric. As the core component of electric motors, the performance of power batteries is crucial. However, existing power battery solutions, especially when applied to construction machinery, generally suffer from insufficient mechanical reliability and low integration, making it difficult to meet the challenges of structural strength and high power requirements under harsh working conditions.

[0003] Currently, the main technical solutions for power batteries in construction machinery include: battery box and bracket combination scheme and battery box stacking scheme.

[0004] The existing solution also has the following drawbacks:

[0005] (1) During vibration (especially in the horizontal direction), the higher the position of the battery box, the greater the vibration acceleration, and the greater the risk of failure of the battery box and its internal parts due to excessive stress.

[0006] (2) During vibration (especially in the horizontal direction), the high center of gravity of the battery system generates a strong overturning moment. The lower the battery box, the greater the moment it experiences. This moment attempts to flip the battery box around its overturning axis, greatly affecting the force distribution of the interlayer bolts. Specifically, under the action of the overturning moment, one side of the battery box tends to lift upwards, and the bolts will bear a huge axial tensile force; the other side tends to press downwards, and the axial tensile force of the bolts will decrease. Under repeated alternating vibration conditions, the axial tensile force of the bolts increases and decreases periodically, making them prone to loosening or even breaking.

[0007] (3) Each battery box has independent positive, negative, and low-voltage plugs, as well as MSD (Manual Service Disconnect) and vent valve, which results in significant redundancy and cost, and makes assembly complex.

[0008] (4) In addition to multiple battery boxes, the battery system also has an independent BDU (Battery Distribution Unit) box, which is usually placed above the top battery box. It not only has a high risk of vibration failure, but also occupies a lot of height space and has low volume utilization.

[0009] (5) Some commercial vehicles and construction machinery have high power discharge requirements. Under the same power, efficiency can be effectively improved by increasing voltage and reducing current. A DC-DC converter may be set up between the battery system and the power system to boost the voltage. The existing DC-DC converter is generally independent and has a low integration rate.

[0010] Therefore, the present invention aims to solve the following technical problem:

[0011] (1) Effectively suppress the vibration of the upper battery box in the stacked battery system.

[0012] (2) Solve the problem that the interlayer connection bolts are prone to loosening under overturning moment.

[0013] (3) Solve the problem of complex external interfaces of the battery box.

[0014] (4) Solve the problem of complex layout and integration of BDU.

[0015] (5) Solve the problem of complex DC-DC layout. Summary of the Invention

[0016] Objective: In order to overcome the shortcomings of the existing technology, the present invention provides a high-strength and highly integrated power battery system.

[0017] Technical solution: To solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0018] A high-strength, highly integrated power battery system includes: multiple battery housings.

[0019] Multiple battery boxes are stacked and fixed in the height direction to form the main body of the battery system, and the top of the main body of the battery system is provided with a cover.

[0020] The side corners and / or side walls of the main body of the battery system are provided with supporting structural members.

[0021] The battery system body has a BDU on its side.

[0022] Optionally, a cooling assembly is provided inside the battery box. The inlet and outlet of the cooling assembly are respectively located on the side wall of the battery box. All inlets of the battery box are connected to the inlet manifold via branches, and all outlets of the battery box are connected to the outlet manifold via branches.

[0023] Optionally, the battery box adopts a box structure with an open top, including: a bottom plate, and a wall enclosing the bottom plate. The wall is divided into thin walls and thick walls according to thickness.

[0024] Optionally, the supporting structure includes: a first supporting member, a second supporting member, a third supporting member, and a fourth supporting member.

[0025] The first support member includes an L-shaped corner joint, and the L-shaped corner joint is provided with mounting holes.

[0026] The second support member includes an L-shaped corner joint, a horizontal connecting part is provided below the L-shaped corner joint, and mounting holes are provided on both the L-shaped corner joint and the horizontal connecting part.

[0027] The third support member includes a connecting block, on which mounting holes are provided.

[0028] The fourth support member includes a connecting block, a horizontal connecting part is provided below the connecting block, a reinforcing block is provided between the connecting block and the horizontal connecting part, and mounting holes are provided on both the connecting block and the horizontal connecting part.

[0029] Optionally, the bolt mounting point along the lower edge of the thin wall is provided with a boss.

[0030] Optionally, a window is provided on the side wall of the battery housing, and the window is used to set an external interface.

[0031] The BDU includes: a cover and a housing, the housing having a control window that cooperates with the battery box.

[0032] Optionally, a BDU mounting bracket is provided on the back of the bottom plate of the housing, and the BDU mounting bracket is fixed to the BDU mounting platform of the battery box with bolts. The control window sill protrudes from the bottom plate and is fixed to the window sill of the battery box with bolts.

[0033] Optionally, a sealing strip is provided on the top of the battery housing.

[0034] Optionally, a sealing strip is provided between the window sills of the control window and the window sills.

[0035] Optionally, the BDU's conversion circuit may also include a buck converter.

[0036] Beneficial effects: The high-strength, highly integrated power battery system provided by this invention has the following advantages compared to existing technologies:

[0037] (1) High strength and high reliability: The battery system is rigidly connected to the main chassis or adjacent system / box by the supporting structural components, which effectively suppresses vibration, especially the acceleration response of the upper box, and solves the reliability problem caused by the overturning moment.

[0038] (2) Excellent anti-loosening performance: The boss design of the bolt installation point between layers improves the anti-loosening performance by increasing the bolt length, ensuring the connection stability of the stacked structure under long-term vibration.

[0039] (3) High integration and low cost: The independent external interfaces of each battery box are eliminated and the BDU is uniformly led out through the window, which greatly reduces the number of connectors, reduces material costs, and simplifies the assembly process.

[0040] (4) Space optimization and convenient maintenance: The side-mounted design of the BDU saves top space and reduces the overall height. The design of the maintenance window makes it extremely convenient to inspect all electrical connections and internal components of the BDU.

[0041] (5) High functional integration: Integrating DCDC into BDU improves system integration and enables the battery system to have voltage regulation capability, making it more adaptable. Attached Figure Description

[0042] Figure 1 This is an isometric drawing of a high-strength, highly integrated power battery system.

[0043] Figure 2 This is an exploded view of a high-strength, highly integrated power battery system.

[0044] Figure 3 This is an isometric view of the battery housing of the present invention.

[0045] Figure 4 This is an enlarged schematic diagram of the bolt mounting bosses between the battery housings of the present invention.

[0046] Figure 5 This is a front view of the battery housing of the present invention.

[0047] Figure 6 This is a front view of the hidden BDU cover of the present invention.

[0048] Figure 7 This is an isometric view of the back of the BDU of the present invention.

[0049] Figure 8 Schematic diagram of BDU circuit for integrating DC-DC converter

[0050] Figure 9 This is a schematic diagram showing the mutual support between multiple power battery systems. Detailed Implementation

[0051] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0052] The present invention will be further described below with reference to specific embodiments.

[0053] Example 1:

[0054] This embodiment introduces a high-strength, highly integrated power battery system, such as... Figure 1 and 2As shown, it includes: multiple battery boxes 1.

[0055] Multiple battery boxes 1 are stacked and fixed in the height direction to form the main body of the battery system. The top of the main body of the battery system is provided with a cover 2. The upper battery box is directly mounted on the lower battery box, acting as the cover of the lower battery box. The bottom battery box is fixed to the main chassis, and the top battery box has an independent cover, which simplifies the structure of the battery system.

[0056] The side wall corners and / or side walls of the main body of the battery system are provided with supporting structural members 3, which are used to further strengthen the connection between battery boxes and reduce the vibration intensity of the battery boxes, especially at higher positions.

[0057] The side of the main body of the battery system is provided with BDU4, which is used to realize the electrical connection between the battery and each battery box.

[0058] Furthermore, a sealing strip is provided on the top of the battery housing 1 to achieve interlayer sealing of the battery housing.

[0059] Furthermore, such as Figure 3 As shown, a cooling assembly 101 is provided inside the battery housing 1. The liquid inlet 102 and liquid outlet 103 of the cooling assembly 101 are respectively provided on the side wall of the battery housing 1. All liquid inlets 102 of the battery housing 1 are connected to the liquid inlet manifold 5 through branches, and all liquid outlets 103 of the battery housing 1 are connected to the liquid outlet manifold 6 through branches, for the thermal management of the battery system.

[0060] Furthermore, the battery box 1 adopts a box structure with an opening at the top, including: a bottom plate 104, and a wall 105 enclosing the bottom plate.

[0061] Furthermore, the wall 105 is divided into thin walls 1051 and thick walls 1052 according to their thickness. The thin walls are used to prevent the intrusion of external foreign objects and to reduce weight, while the thick walls form vertical columns to strengthen the box structure and facilitate the installation of the supporting structural components 3.

[0062] Furthermore, the thick wall 1052 is disposed in the middle and corner positions of the wall 105, and a mounting base is provided on the thick wall.

[0063] Furthermore, the supporting structure 3 includes: a first supporting member 301, a second supporting member 302, a third supporting member 303, and a fourth supporting member 304.

[0064] The first support member includes an L-shaped corner joint, which has mounting holes for fixed connection to the corner of the side wall of the battery system body.

[0065] The second support member includes an L-shaped corner joint, and a horizontal connecting part is provided below the L-shaped corner joint. Both the L-shaped corner joint and the horizontal connecting part are provided with mounting holes for the side wall corner of the battery system body and for fixed connection with the vehicle chassis.

[0066] The third support includes a connecting block with mounting holes for fixed connection to the side wall of the battery system body.

[0067] The fourth support member includes a connecting block, a horizontal connecting part is provided below the connecting block, a reinforcing block is provided between the connecting block and the horizontal connecting part, and mounting holes are provided on both the connecting block and the horizontal connecting part for fixed connection with the side wall of the battery system body and the vehicle chassis.

[0068] By using four different support structures, it is possible to fix the upper and lower battery boxes together in situations where the main chassis structure is limited, especially when it is impossible to support the battery box at a higher position. In this way, the vibration of the upper battery box can be easily suppressed by the lower battery box.

[0069] Furthermore, such as Figure 4 As shown, a boss 106 is provided at the bolt mounting point on the lower edge of the thin-walled 105 to increase the bolt length. Under the same torque and preload conditions, the longer bolt has a greater absolute elongation and stores more elastic energy. In addition, when the load changes during vibration and the upper and lower battery boxes tend to separate, the longer bolt requires a longer relaxation stroke to reduce the preload below the critical point, thus achieving a better anti-loosening effect.

[0070] Furthermore, such as Figure 5 , Figure 6 , Figure 7 As shown, a window 107 is provided on the side wall of the battery box 1, and the window is used to set the external interface.

[0071] The window's location and size cover the external interfaces inside the battery box. These interfaces include: the high-voltage positive interface 121 and the high-voltage negative interface 122, which are connected via copper busbars or wire harnesses; and the low-voltage interface 123, which is connected via a wire harness. All interfaces pass through the window and enter the BDU from inside the box. This facilitates the installation and removal of the high-voltage and low-voltage interfaces for each battery box 1.

[0072] The BDU4 includes a cover 401 and a housing 402. The housing 402 has a control window 403 that cooperates with the battery box. The electrical components (contactors, shunts, wiring harnesses, etc.) inside the housing are connected to electrical interfaces (positive and negative terminals of the battery system, low-voltage connectors, vent valves, etc.) installed on the wall. Multiple control windows are provided on the back of the housing, corresponding to the windows of each battery box. After opening the BDU cover, the battery system can be easily disassembled and reassembled, and the electrical components inside the BDU housing can be easily inspected and maintained.

[0073] Furthermore, the housing 402 includes a bottom plate and side walls. A BDU mounting base 404 is provided on the back of the bottom plate, which is fixed to the BDU mounting platform 132 of the battery housing 1 by bolts. The control window sill 405 protrudes from the bottom plate and is fixed to the window sill 131 of the battery housing by bolts. In addition, there is a sealing strip between the two. After the bolts are tightened, the sealing strip is compressed and deformed to achieve a sealing effect.

[0074] Furthermore, traditional BDU electrical solutions primarily rely on closing / opening contactors to power / disconnect the host electrical system, making it impossible to adjust the battery system voltage platform. This invention integrates the DC-DC converter into the BDU, enabling adjustable output voltage from the battery system. For example... Figure 8 As shown, the area outside the dashed box represents a common BDU electrical scheme, while the area inside the box represents a DC-DC converter that can either boost or buck voltage.

[0075] The buck converter circuit comprises five basic parts: input voltage Vin, switch S1, diode D1, an LC filter consisting of inductor L and capacitor C, and output voltage Vout. Its operation is divided into two stages (S2, used for boosting, remains closed in each stage): In the first stage, switch S1 is closed, diode D1 is reverse-biased and cut off, and current flows from the positive terminal of Vin through switch S1, then through inductor L1, charging capacitor C1 and supplying power to the load, finally returning to the negative terminal of Vin. During this stage, both inductor L1 and capacitor C1 store energy. In the second stage, switch S1 is open, disconnecting the input Vin from the output Vout. Inductor L1 generates an induced electromotive force (EMF) to counteract the decrease in current. This EMF is positive on the left and negative on the right, causing diode D1 to be forward-biased and conduct. Inductor L1 and capacitor C1 together supply power to the load. S1 rapidly switches between the first and second stages, periodically alternating, cutting the input voltage Vin into pulses, which are then smoothed using the LC filter to obtain a lower average output voltage Vout. A boost converter circuit consists of six basic parts: input voltage Vin, inductor L1, switch S2, diode D2, capacitor C, and output voltage Vout. Unlike a buck converter, in a boost converter, switch S2 is located at the right end of inductor L1 and is connected in parallel with capacitor C1 and the load. The diode is also located at the right end of inductor L1. Its operation is divided into two stages (S1 remains closed in each stage): In the first stage, switch S2 is closed, pulling the right end of inductor L1 to a low potential, causing diode D2 to be reverse-biased and cut off. Current flows from the positive terminal of Vin through inductor L1 and switch S2, then back to the negative terminal of Vin. In this stage, inductor L1 stores energy. In the second stage, switch S2 is open, cutting off the current. Inductor L1 generates an induced electromotive force (EMF) to attempt to maintain the current. This induced EMF has a polarity of negative on the left and positive on the right, and is added in series with the input voltage Vin. At this time, the voltage applied to capacitor C1 and the load is Vin plus the induced voltage of the inductor. S2 enables the first and second stages to operate alternately in a cycle by rapidly switching on and off, and by utilizing the storage and release of inductors, it outputs electrical energy in the form of higher voltage.

[0076] Example 2:

[0077] This embodiment describes the cascaded structure of the power battery system in Embodiment 1, such as... Figure 9 As shown, for a host with high power demand, multiple power battery systems may be installed. A cross-system connection structure 6 is set between the power battery systems to enable mutual support between adjacent power battery systems.

[0078] Example 3:

[0079] The innovative aspect of this invention lies in its working principle, which is as follows:

[0080] (1) A structure that uses a supporting structure in a stacked battery system to suppress vibration and improve mechanical strength by using the main chassis, the lower battery box or the adjacent battery system.

[0081] (2) The boss structure at the bolt mounting point between the battery box layers is designed to increase the bolt length to prevent loosening.

[0082] (3) The battery box eliminates the independent external interface and integrates the high and low voltage connection lines through the wiring wall window.

[0083] (4) The layout and structure of hanging the BDU on the battery system wiring side and achieving electrical connection and sealing with each battery box through the corresponding window.

[0084] (5) Electrical architecture and specific circuit implementation scheme for integrating the DC-DC converter into the BDU.

[0085] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-strength, highly integrated power battery system, characterized in that: include: Multiple battery enclosures; Multiple battery boxes are stacked and fixed in the height direction to form the main body of the battery system, and the top of the main body of the battery system is provided with a cover; The side wall corners and / or side walls of the main body of the battery system are provided with supporting structural components; The battery system body has a BDU on its side.

2. The high-strength, highly integrated power battery system according to claim 1, characterized in that: The battery box is equipped with a cooling assembly. The inlet and outlet of the cooling assembly are respectively located on the side wall of the battery box. All the inlets of the battery box are connected to the inlet manifold through branches, and all the outlets of the battery box are connected to the outlet manifold through branches.

3. The high-strength, highly integrated power battery system according to claim 1, characterized in that: The battery box adopts a box structure with an open top, including: a bottom plate, and a wall enclosing the bottom plate. The wall is divided into thin wall and thick wall according to its thickness.

4. The high-strength, highly integrated power battery system according to claim 1, characterized in that: The supporting structure includes: a first supporting member, a second supporting member, a third supporting member, and a fourth supporting member; The first support member includes an L-shaped corner joint, and the L-shaped corner joint is provided with mounting holes; The second support member includes an L-shaped corner joint, a horizontal connecting part is provided below the L-shaped corner joint, and mounting holes are provided on both the L-shaped corner joint and the horizontal connecting part; The third support member includes a connecting block, and the connecting block is provided with mounting holes; The fourth support member includes a connecting block, a horizontal connecting part is provided below the connecting block, a reinforcing block is provided between the connecting block and the horizontal connecting part, and mounting holes are provided on both the connecting block and the horizontal connecting part.

5. A high-strength, highly integrated power battery system according to claim 3, characterized in that: The bolt mounting points along the lower edge of the thin wall are provided with bosses.

6. The high-strength, highly integrated power battery system according to claim 1, characterized in that: The side wall of the battery enclosure is provided with a window for setting an external interface; the BDU includes: a cover and a box, the box being provided with a control window that cooperates with the battery enclosure.

7. A high-strength, highly integrated power battery system according to claim 6, characterized in that: A BDU mounting base is provided on the back of the bottom plate of the box body. The BDU mounting base is fixed to the BDU mounting platform of the battery box body by bolts. The control window ridge of the box body protrudes from the bottom plate and is fixed to the window ridge of the battery box body by bolts.

8. A high-strength, highly integrated power battery system according to claim 1, characterized in that: A sealing strip is provided on the top of the battery box.

9. A high-strength, highly integrated power battery system according to claim 7, characterized in that: A sealing strip is provided between the window sills of the control window and the window sills.

10. A high-strength, highly integrated power battery system according to claim 1, characterized in that: The conversion circuit of the BDU also includes a step-down circuit.

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