Lithium battery pack

Abstract

The invention relates to the technical field of lithium battery packs, in particular to a lithium battery pack which comprises a cuboid shell mechanism, battery modules, a fixing assembly and a buffering mechanism, the shell mechanism comprises a shell frame and battery partition plates, the shell frame and the battery partition plates cooperate to limit a battery cavity array, and the battery modules are embedded in battery cavities; the fixing assembly is inserted into a limiting groove in the inner side of the shell frame and is used for restraining lateral displacement of the battery module; and the buffer mechanism is arranged in the battery chamber and comprises a cushioning plate and a cushioning assembly, and the cushioning plate of the buffer mechanism clamps the battery module in a front-back symmetrical mode. The lithium battery pack is improved aiming at the problems of short circuit, thermal runaway chain reaction and the like easily caused by damage of an internal structure when the lithium battery pack encounters physical impact in the prior art. According to the invention, through cooperative arrangement of the ceramic composite shell frame and the self-adaptive hydraulic buffer system, mechanical impact protection is realized, and the safety of the battery system under complex working conditions is improved.

Description

Technical Field

[0001] This invention relates to the field of lithium battery pack technology, and specifically to a lithium battery pack. Background Technology

[0002] With the rapid development of applications such as electric vehicles, portable electronic devices, and energy storage systems, lithium batteries are widely used due to their high energy density, low self-discharge rate, and long service life. Lithium-ion battery packs, as the core power supply component, are typically composed of multiple cells connected in series or parallel and encapsulated in a metal or plastic casing. However, in practical applications, due to the complex and variable operating environment, such as in traffic accidents or severe collisions, battery packs may be subjected to external forces such as mechanical impact, compression, puncture, or severe vibration. Under these conditions, the internal structure of the battery, such as the separator, electrode materials, and electrolyte, is prone to deformation, damage, or even short circuits, leading to thermal runaway and potentially causing serious safety accidents such as fires or even explosions. This safety hazard not only threatens the safety of the equipment itself but also poses a significant risk to the personal safety of users. Therefore, higher requirements are placed on the impact resistance and safety protection structure of lithium battery packs.

[0003] Currently common lithium battery protection methods include electronic safety measures such as temperature detection, voltage detection, overcurrent protection, and cell balancing management. While these can improve system stability to some extent, they still have technical vulnerabilities when the battery pack encounters physical impacts. For example, traditional battery pack structures often use rigid connections, which, when subjected to external impacts, lack effective buffering and energy absorption space between cells, easily causing direct damage to internal components, triggering electrochemical reactions and releasing large amounts of heat. Furthermore, some battery packs lack zoned protection and flame-retardant isolation designs. If a single cell experiences thermal runaway, it can easily spread to other cells in a very short time, forming a chain reaction and ultimately leading to the collapse of the entire system. Therefore, there is an urgent need to propose a lithium battery pack structure with higher mechanical shock resistance to curb the risk of fire or explosion caused by collisions at the source, and improve the operational safety and reliability of lithium batteries under complex operating conditions.

[0004] In view of the above, in order to overcome the above technical problems, the present invention designs a lithium battery pack, which solves the above technical problems. Summary of the Invention

[0005] The technical objective of this invention is to design a lithium battery pack with effective buffer and energy absorption spaces between the cells to reduce direct damage to internal components, thereby avoiding triggering electrochemical reactions and releasing a large amount of heat energy.

[0006] To achieve the above-mentioned technical objectives, the present invention provides the following technical solution: The present invention is achieved through the following technical solution: The present invention discloses a lithium battery pack, including a cuboid shell mechanism, a battery module, a fixing component and a buffer mechanism. The shell mechanism includes a shell frame and a battery separator, which together define a battery chamber array. The battery module is embedded in the battery chamber. The fixing component is inserted into the inner limiting groove of the shell frame to constrain the lateral displacement of the battery module. The buffer mechanism is located inside the battery chamber and includes a damping plate and damping components. The damping plate of the buffer mechanism symmetrically clamps the battery module from front to back. The damping plates of adjacent battery chambers are rigidly connected by connecting columns to form a stress transmission chain across the chambers. The impact energy is distributed and transmitted through the connecting columns to multiple damping components for coordinated dissipation.

[0007] Furthermore, the outer frame and battery separator are made of ceramic composite material, and the length of the battery chamber is reserved for operation. The reserved length of the battery chamber provides operation space for the lateral disassembly and assembly of the battery module, avoiding damage to the module or connectors due to limited space. At the same time, the ceramic material forms a rigid skeleton in the separator or frame, which is not easy to shrink and melt at high temperature, and can block the external short circuit arc and slow down the heat spread rate inward.

[0008] Furthermore, the fixing component includes a cuboid fixing block, a dovetail section limiting block, and a rotary bolt. The limiting block engages with the limiting groove of the outer shell frame in a wedge shape. The fixing component provides rigid carrier support through the cuboid fixing block and integrates the wedge engagement between the dovetail section limiting block and the limiting groove of the outer shell frame, thereby achieving lateral self-locking to suppress vibration displacement.

[0009] Furthermore, the shock absorption assembly includes a buffer block, a pad, and a connecting pipe. The buffer block is located between the shock absorption plate and the battery separator, and its interior integrates a storage cavity filled with hydraulic oil. The buffer blocks in adjacent battery chambers are interconnected through the connecting pipe penetrating the battery separator. The shock absorption assembly achieves fluid migration and balanced dissipation of impact energy by the hydraulic oil in the oil storage cavity of the insulating buffer block flowing across the chambers through the connecting pipe penetrating the separator. At the same time, the obtuse-angled triangular pad disperses stress and triggers oil pressure transmission, forming a multi-level buffer barrier.

[0010] Furthermore, the pad is fixed to the contact surface of the buffer block, with an obtuse triangular cross section and the vertex pointing towards the damping plate. The position of the pad corresponds to the storage cavity, and when compressed, it concentrates the pressure to the storage cavity.

[0011] Furthermore, a through hole is centrally located inside the buffer block for the connecting column to pass through, and a hollow annular groove is provided around the through hole to absorb impact kinetic energy. The hollow annular groove has a built-in damping spring to provide elastic reset function. The buffer block is divided into three parts by an isolation groove: the middle part contains a through hole and a shock-absorbing spring, and the two side parts contain storage cavities.

[0012] Furthermore, a flow channel is opened inside the battery separator, and the buffer block storage cavity and the flow channel are fixed at both ends of the connecting pipe, respectively. An adaptive throttling component is coaxially nested inside the flow channel.

[0013] Furthermore, the adaptive throttling assembly includes a fixed ring, double sliding pillars, and a return spring; The outer wall of the fixed ring is fixed to the flow channel, and the ring body has an array of flow holes in the axial direction. The double sliding column has a T-shaped symmetrical structure. Its small diameter end is dynamically sealed to the inner wall of the fixed ring, and its large diameter end is dynamically sealed to the inner wall of the flow channel. The return spring is located between the large diameter end of the sliding column and the end face of the fixed ring.

[0014] Furthermore, the slide column integrates an axially penetrating first flow channel and a radially connected second flow channel. The second flow channel includes a central hole, a radial inner hole, and a spiral gradient liquid outlet hole array, with the liquid outlet holes arranged in axial height difference order along the outer wall of the small diameter end of the slide column.

[0015] Furthermore, during a strong impact, the oil pressure at the impact end increases dramatically, forcing the sliding column to move axially. The inner wall of the fixed ring seals the liquid outlet holes sequentially along a spiral gradient. The oil can only flow through the limited cross-sectional area of ​​the first flow channel, and the flow resistance surges to enhance the buffer stiffness.

[0016] The beneficial effects of this invention are as follows: (1) This invention dissipates external impact energy through a shock-absorbing mechanism that utilizes the synergistic effect of multi-stage physical deformation and fluid damping. Specifically, when the battery module is subjected to an external impact, the impact force is first received by a soft rubber pad with an obtuse triangular cross-section. Its hypotenuse configuration converts the longitudinal impact into multi-directional stress diffusion, simultaneously reducing the instantaneous peak stress. Subsequently, the impact energy is conducted through the pad to the low-pressure hydraulic oil inside the buffer block. Driven by the pressure difference, the hydraulic oil migrates to adjacent chambers through the connecting pipe, converting the local impact kinetic energy into fluid kinetic energy and achieving stress distribution across chambers. At the same time, the hollow annular groove of the buffer block actively absorbs residual energy through thin-wall deformation, while the built-in shock-absorbing spring provides elastic restoring force, suppressing material fatigue. This reduces the risk of short circuits caused by mechanical damage.

[0017] (2) This invention utilizes a composite buffering mechanism combining a spiral gradient liquid outlet throttling component and cross-chamber hydraulic linkage. When the battery pack is subjected to a weak impact, the low-pressure hydraulic oil flows freely through the open flow channels (first flow channel + second flow channel) of the double sliding column. Combined with the multi-directional stress diffusion of the obtuse-angled triangular cross-section of the soft rubber pad, it flexibly absorbs vibration energy. When a strong impact triggers a surge in oil pressure, the axial displacement of the sliding column causes the inner wall of the fixed ring to sequentially block the liquid outlet along the spiral gradient. The flow cross-sectional area shrinks in a stepwise manner, and the oil flow resistance increases exponentially, forcing the oil pressure at the impact end to rise dynamically. The stiffness of the buffer block is instantly enhanced, forming a rigid support to resist strong impacts. Through mechanical pressure feedback, a closed-loop regulation is achieved, which includes self-identification of impact intensity, adaptive buffer hardness, and balanced energy dissipation across chambers, suppressing the risk of diaphragm tearing and electrode deformation caused by mechanical stress in the battery module. Attached Figure Description

[0018] 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.

[0019] The above and other aspects of the invention will now be described by way of example only, with reference to the accompanying drawings, in which: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the outer shell structure of the present invention; Figure 3 This is a schematic diagram of the structure of the fixing component of the present invention; Figure 4 This is a schematic diagram of the structure of the buffer block of the present invention; Figure 5 This is a schematic diagram of the cross-sectional structure of the buffer block and partition of the present invention; Figure 6 This is the present invention. Figure 1 A magnified schematic diagram of the structure at point A; Figure 7 This is a schematic diagram of the internal structure of the buffer block of the present invention; Figure 8 This is a schematic diagram of the structure of the buffer block and pad block of the present invention; Figure 9 This is a schematic diagram of the adaptive throttling component of the present invention; Figure 10 This is a schematic cross-sectional view of the sliding column structure of the present invention; Figure 11 This is the present invention. Figure 5 A magnified schematic diagram of the structure at point B.

[0020] In the diagram: 1. Outer shell mechanism; 2. Battery module; 3. Battery chamber; 4. Fixing component; 5. Mounting hole; 6. Connecting post; 7. Buffer mechanism; 8. Isolation groove; 9. Adaptive throttling component; 10. Flow channel; 11. Flow hole; 12. Return spring; 13. First flow channel; 14. Second flow channel; 901. Fixing ring; 902. Sliding column; 101. Outer shell frame; 102. Limiting groove; 103. Battery separator; 401. Fixing block; 402. Limiting block; 403. Pull bolt; 701. Shock absorber plate; 702. Shock absorber component; 721. Buffer block; 722. Storage chamber; 723. Connecting pipe; 724. Pad; 7211. Through hole; 7212. Hollow ring groove; 7213. Shock absorber spring; 131. Center hole; 132. Inner hole; 133. Liquid outlet. Detailed Implementation

[0021] The embodiments of the present invention are described in detail below. These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments. In the description of the present invention, words such as "front", "rear", "left", and "right" that indicate orientation or positional relationship are only for the convenience of describing the present 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. Therefore, they should not be construed as limitations on the present invention.

[0022] As shown in Figures 1-9, this embodiment discloses a lithium battery pack, which adopts an integrated rectangular shell, forming a basic protective frame through the outer shell mechanism 1, and embedding a battery module 2 inside as the energy storage core.

[0023] Specifically, such as Figure 1 and Figure 2 As shown, the outer casing mechanism 1 includes an outer casing frame 101, a limiting groove 102, and a battery separator 103; it adopts an integrated layout of frame and separator, with the outer casing frame 101 and the built-in battery separator 103 working together to form an array of battery chambers 3. Each battery chamber 3 has a reserved operating margin in the length direction to provide lateral operating space for the disassembly and assembly of the battery module 2; while the inner side of the outer casing frame 101 has a limiting groove 102, and a fixing component 4 is inserted and fitted at the limiting groove 102 to ensure that the battery module 2 is laterally limited and avoids lateral displacement.

[0024] It should be noted that both the battery separator 103 and the outer frame 101 are made of ceramic composite material, which can effectively improve the insulation and thermal resistance of the entire battery pack while ensuring structural strength.

[0025] like Figures 1-3As shown, the fixing component 4 includes a fixing block 401, a limiting block 402, and a pull bolt 403. The cuboid fixing block 401 serves as a rigid carrier and is attached to both sides of the battery module 2. The limiting block 402 with a dovetail cross section is integrated on its inner side, and displacement constraint is achieved through wedge-shaped engagement with the limiting groove 102. The transverse trapezoidal inclined surface generates a self-locking effect to suppress vibration displacement. In addition, a rigid stop can be constructed on its longitudinal right-angle surface to prevent axial disengagement. The top-mounted rotary handle pull bolt 403 is driven by forward and reverse rotation to realize the assembly and disassembly of the locking mechanism.

[0026] Considering the complexity and variability of the operating environment in real-world applications (such as extreme conditions like traffic accidents or severe collisions), lithium battery packs are highly susceptible to strong external forces such as mechanical shocks or high-frequency vibrations. These forces can cause structural damage, including tearing of the internal separator, deformation of electrode materials, and electrolyte leakage, potentially leading to internal short circuits and a chain reaction of thermal runaway, which could ultimately escalate into catastrophic safety accidents such as fires or even explosions. These hazards not only directly threaten the functional integrity of the equipment but also pose a serious challenge to user safety. Therefore, it is urgent to enhance the structural stability of battery packs by integrating shock-resistant protection mechanisms to systematically suppress safety risks caused by external forces.

[0027] To improve the impact resistance of the battery pack, such as Figure 1 , Figure 2 , Figure 4 , Figure 5 , Figure 6 As shown, mounting holes 5 are provided at the battery separators 103 between each battery chamber 3, and connecting posts 6 are movably inserted to serve as the load-bearing support core. Simultaneously, buffer mechanisms 7 are symmetrically arranged front and rear inside each chamber. These mechanisms achieve force transmission and coordinated operation through the connecting posts 6. When the battery pack suffers an external impact, the buffer mechanism 7 absorbs energy through elastic deformation, effectively dispersing the impact load transmitted to the connecting posts 6, thereby suppressing direct damage to the internal structure of the battery from mechanical stress and reducing the risk of thermal runaway.

[0028] The buffer mechanism 7 includes a damping plate 701 and a damping component 702. Each battery chamber 3 is equipped with a damping plate 701 that can move along the front-to-back direction of the chamber, and the battery module 2 is sandwiched between the two plates. When an external impact acts on the battery module 2, the impact force is directly transmitted to the damping plate 701. The damping plates 701 of adjacent chambers are rigidly connected by connecting columns 6, forming a stress transmission chain across the chambers. Impact energy can be transmitted step-by-step to adjacent damping plates 701 via the connecting columns 6, achieving distributed dissipation of impact force. In addition, a shock-absorbing component 702 is added between the shock-absorbing plate 701 and the separator inside the cavity. It absorbs local impact energy through elastic deformation and suppresses the direct transmission of stress to the internal structure of the battery. The rigid linkage of the damping plate 701 and the elastic energy absorption of the damping component 702 form a multi-level buffer system, which not only ensures the hierarchical transmission and dispersion of impact energy, but also reduces the instantaneous peak stress through local deformation, thus jointly improving the structural integrity and impact resistance of the battery pack under mechanical impact.

[0029] like Figure 4 , Figure 5 , Figures 7-8 As shown, the damping assembly 702 includes a buffer block 721, a storage cavity 722, a pad 724, and a connecting pipe 723. The buffer block 721 is made of a high-toughness insulating material, possessing both excellent electrical insulation and deformation energy absorption capabilities, and is located between the battery separator 103 and the damping plate 701. Its interior integrates the storage cavity 722, which is filled with hydraulic oil as a buffering medium. Furthermore, the buffer blocks 721 of adjacent battery chambers 3 are interconnected across chambers via the connecting pipe 723. The connecting pipe 723 is fixed to the side of the storage cavity 722 facing the separator and communicates with the storage cavity 722 inside the adjacent buffer block 721 through an opening inside the separator, creating a free-flowing channel for hydraulic oil between adjacent storage cavities 722.

[0030] Specifically, a flow channel 10 is provided inside the battery separator 103, and the connecting pipes 723 of the front and rear buffer blocks 721 are fixedly connected to and connected to the flow channel 10, so that the buffer blocks 721 of adjacent battery chambers 3 can be interconnected across chambers through the connecting pipes 723.

[0031] When an external impact causes displacement of battery module 2, the impact force is transmitted to buffer block 721 via damping plate 701, triggering compression deformation of buffer block 721 and separator. At this time, hydraulic oil, driven by pressure difference, dynamically flows between adjacent storage chambers 722 through connecting pipe 723, converting local impact energy into fluid kinetic energy and dispersing it across chambers. This design, through the adaptive migration of the fluid medium, absorbs the instantaneous peak impact energy and balances the stress distribution between multiple chambers, reducing the risk of damage to the battery structure. This forms a multi-stage buffer system, improving the battery pack's shock resistance while enhancing the system's adaptive protection capability under sudden collision conditions through the dynamic dissipation and transfer of impact energy, thus extending battery cycle life.

[0032] Specifically, the pad 724 is fixed to the contact surface of the buffer block 721 facing the damping plate 701 and corresponds to the position of the storage cavity 722. Its function is to become the direct force interface of the damping plate 701 during impact transmission. When the damping plate 701 is compressed and displaced, the pad 724 concentrates the pressure and transmits it to the storage cavity 722, forcing the hydraulic oil in the cavity to dynamically migrate to the buffer block 721 in the adjacent cavity through the connecting pipe 723, and simultaneously triggering the fluid damping buffer effect.

[0033] More specifically, the pad 724 is made of soft rubber through molding, and by relying on the material's high elasticity and energy dissipation characteristics, it effectively absorbs and converts impact kinetic energy.

[0034] In addition, the 724 pad section is set as an obtuse triangle. Through its obtuse triangle section setting, the hypotenuse of the triangle generates a radial component force when under pressure, which transforms the longitudinal impact into multi-directional stress diffusion. The obtuse angle vertex forms a self-locking support, reducing the risk of plastic deformation. Therefore, by reducing the instantaneous peak impact stress and balancing the load distribution, the fatigue life of the pad 724 itself and related components (such as the damping plate 701 and the connecting column 6) is extended simultaneously.

[0035] Specifically, such as Figure 7 and Figure 8 As shown, the buffer block 721 includes a through hole 7211, a hollow annular groove 7212, and a damping spring 7213. The centrally located through hole 7211 provides clearance for the connecting post 6, ensuring stable transmission of axial loads; its outer hollow annular groove 7212 actively absorbs impact kinetic energy with its thin-walled deformation structure, while the built-in damping spring 7213 simultaneously provides elastic restoring function. This composite structure improves the instantaneous impact energy conversion rate and, through the continuous rebound of the spring, suppresses material fatigue, enhancing the structural durability and impact resistance of the buffer block 721.

[0036] like Figure 4 As shown, the buffer block 721 has two isolation grooves 8, both located between the through hole 7211 and the storage cavity 722, dividing the buffer block 721 into three independent parts. The middle part, close to the connecting post 6, has high rigidity and can withstand large structural loads. Simultaneously, it achieves effective shock absorption and energy absorption through the hollow annular groove 7212 and the damping spring 7213, thereby reducing the direct transmission of impact force to the connecting post 6 and the overall structure. The two side parts each have a storage cavity 722 to contain a liquid medium. When the damping assembly 702 is impacted, the pad 724 first disperses the impact force, and then the impact force is transmitted through the pad 724 to the liquid medium in the storage cavity 722, allowing the liquid medium to evenly distribute and absorb the impact energy, further improving the damping effect. Through this multi-layered design, the buffer block 721 not only achieves efficient impact energy management but also ensures the stability and safety of the battery pack under complex operating conditions.

[0037] With the above configuration, when an external impact causes displacement of the battery module 2, multi-level buffering protection is provided by the buffer mechanism 7. In practical applications, the buffer mechanism 7 of the battery module 2 achieves multi-level buffering protection through the hydraulic damping of the internal oil reservoir. However, due to the unpredictability of external impacts (such as a slight swaying or a severe collision during vehicle operation), the impact force range faced by the buffer block 721 is extremely wide. If the preset oil pressure of the oil reservoir is high, it can cope with strong impacts, but under weak impacts, the buffer block 721 will not deform sufficiently and will make near-rigid contact, thus losing its buffering effect. Conversely, if the preset oil pressure is low, it can absorb weak impact energy, but the damping force is insufficient to effectively resist strong impacts. This fixed oil pressure design is difficult to adapt to wide-range impact loads, resulting in a mismatch between buffering performance and operating conditions.

[0038] Therefore, in this embodiment, the internal oil pressure of the buffer block 721 is preset to a low initial oil pressure. An adaptive throttling component 9 is integrated within the flow channel 10 of the battery separator 103, and the connecting pipe 723 of the front and rear buffer blocks 721 is interconnected with the channel through a connector. The cross-sectional flow area of ​​the adaptive throttling component 9 normally maintains a preset initial value. When subjected to a large impact, the change in oil pressure at the impact end triggers the component to adaptively shrink the flow cross-section, causing a surge in oil flow resistance, thereby forcing the internal oil pressure at the impact end to rise rapidly, dynamically enhancing the buffering force to match the impact intensity.

[0039] Specifically, such as Figure 9 , Figure 10 and Figure 11 As shown, the core structure of the adaptive throttling component 9 includes a fixed ring 901 and two sliding pillars 902 coaxially nested within the flow channel 10. The outer wall of the fixed ring 901 is fixedly connected to the channel, and its ring body has an axially arranged annular array of flow holes 11; two T-shaped sliding pillars 902 are symmetrically inserted into both ends of the ring, with their small-diameter ends dynamically sealing against the inner wall of the fixed ring 901, and their large-diameter ends dynamically sealing against the inner wall of the flow channel 10. A return spring 12 is provided between the large-diameter ends of the two sliding pillars 902 and the fixed ring 901, and the spring is fully released under normal conditions. The sliding pillars 902 integrate a dual-flow channel system; The dual-channel system specifically includes a first channel 13 and a second channel 14; the first channel 13 is a series of multiple axially penetrating channels at the large diameter end in a ring array, allowing oil to flow directly through it; The second flow channel 14 is composed of a central hole 131, a radial inner hole 132, and an annular array of liquid outlet holes 133. The central hole 131 is axially located along the slide column 902 and is at its center. The inner hole 132 is provided inside the small-diameter end of the slide column 902. The liquid outlet holes 133 are located on the outer wall of the small-diameter end and are radially located therein, and the liquid outlet holes 133 communicate with the inner hole 132. Under normal conditions, the liquid outlet holes 133 are exposed in the open chamber between the large-diameter end and the end face of the fixed ring 901, and the oil can flow bidirectionally through the first flow channel 13, the second flow channel 14, and the flow hole 11 of the fixed ring 901.

[0040] Under minor impact conditions, the oil pressure increase at the impact end is limited, the displacement of the sliding column 902 is minimal, and the outlet hole 133 remains in the open chamber position. At this time, the oil flow path remains unchanged, the flow cross-sectional area remains large, the flow resistance is low, and the buffer block 721 exhibits a flexible response, effectively absorbing the energy of minor vibrations.

[0041] When a large impact triggers adaptive adjustment, the surge in oil pressure at the impact end forces the large-diameter end of the slide column 902 to compress the return spring 12 axially, causing the outlet hole 133 to slide into the inner cavity of the fixing ring 901. The inner wall of the fixing ring 901 then blocks the outlet hole 133, cutting off the function of the second flow channel 14. The oil can only flow through the limited cross-sectional area of ​​the first flow channel 13, resulting in a sharp drop in flow capacity. Under this constraint, the oil flow resistance at the impact end surges, the internal oil pressure rises rapidly, enhancing the stiffness of the buffer block 721 on that side and forming a rigid support to resist the strong impact.

[0042] It should be noted that the dynamic seal of the sliding column 902, the fixed ring 901, and the inner wall of the channel adopts a stepped sealing ring, which takes into account both high pressure sealing and low friction characteristics. The area of ​​the flow hole 11 of the fixed ring 901 must be greater than the total area of ​​the first flow channel 13 to ensure that the basic flow capacity is maintained under extreme working conditions.

[0043] Furthermore, it should be noted that in this embodiment, by spirally setting an annular array of liquid outlet holes 133 on the outer wall of the small-diameter end of the sliding column 902, the axial height of each hole is arranged in a gradient order along the axis of the column. When the sliding column 902 is pressed and displaced into the inner cavity of the fixed ring 901, the inner wall of the fixed ring 901 will sequentially block the liquid outlet holes 133 at different heights along the climbing direction of the orifice, thereby reducing the effective flow cross-sectional area in stages according to the impact intensity, and realizing an adaptive adjustment mechanism of increasing impact load → stepwise decrease in flow area → gradual increase in flow resistance → smooth increase in buffer hardness.

[0044] During operation, when an external impact causes displacement of the battery module 2, the impact force is transmitted to the pad 724 via the damping plate 701. The obtuse-angled triangular cross-section of the soft rubber pad 724 converts the longitudinal impact into multi-directional stress diffusion, while concentrating the pressure in the storage cavity 722 of the buffer block 721. The low-pressure hydraulic oil in the cavity flows to the adjacent buffer block 721 through the connecting pipe 723 under the pressure difference, thus dissipating the impact energy. At this time, the adaptive throttling component 9 integrated in the flow channel 10 of the baffle plate starts to adjust. Under normal conditions, the dual flow channels of the slide column 902 (the first flow channel 13 that runs through the axis and the second flow channel 14 containing the spiral gradient liquid outlet hole 133) maintain the maximum flow area, with low oil flow resistance and flexible absorption of slight vibrations. When a strong impact causes a sharp increase in oil pressure, the slide column 902 at the impact end moves axially under pressure, the return spring 12 is compressed, and the inner wall of the fixing ring 901 seals the liquid outlet hole 133 in sequence along the spiral gradient, reducing the effective cross-sectional area of ​​the second flow channel 14 in stages, and finally retaining only the limited flow capacity of the first flow channel 13. The stepped contraction of the flow cross section doubles the oil flow resistance, forcing the oil pressure at the impact end to rise rapidly, and the stiffness of the buffer block 721 is dynamically enhanced, forming a rigid support to resist strong impacts. Throughout the process, through the migration of the fluid medium, the adaptive adjustment of the throttling cross section, and the stress dispersion across the chambers, the hierarchical transformation and balanced dissipation of impact energy are achieved, improving the robustness and cycle life of the system under impact loads.

[0045] Various modifications to this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of this disclosure. Therefore, this disclosure is not limited to the examples and designs described herein, but should be given the broadest scope consistent with the principles and novel features disclosed herein. Although one or more exemplary embodiments of this disclosure have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of this disclosure as defined by the appended claims.

Claims

1. A lithium battery pack, comprising a cuboid housing (1), a battery module (2), a fixing component (4), and a buffer mechanism (7), characterized in that, The outer shell mechanism (1) includes an outer shell frame (101) and a battery separator (103), which together define the array of battery chambers (3). The battery module (2) is embedded in the battery chamber (3). The fixing component (4) is inserted into the inner limiting groove (102) of the outer shell frame (101) to constrain the lateral displacement of the battery module (2). The buffer mechanism (7) is located inside the battery chamber (3), and includes a damping plate (701) and a damping component (702). The damping plate (701) of the buffer mechanism (7) symmetrically clamps the battery module (2) from front to back. The damping plates (701) of adjacent battery chambers (3) are rigidly connected by connecting columns (6) to form a cross-chamber stress transmission chain. The impact energy is distributed and transmitted through the connecting columns (6) to multiple damping components (702) for coordinated dissipation.

2. A lithium battery pack according to claim 1, characterized in that: The outer frame (101) and the battery separator (103) are made of ceramic composite material, and the battery chamber (3) has a reserved operating margin in the length direction.

3. A lithium battery pack according to claim 1, characterized in that: The fixing component (4) includes a cuboid fixing block (401), a dovetail section limiting block (402), and a handle-type pull bolt (403). The limiting block (402) engages with the limiting groove (102) of the outer shell frame (101) in a wedge shape.

4. A lithium battery pack according to claim 1, characterized in that: The shock-absorbing assembly (702) includes a buffer block (721), a pad block (724), and a connecting pipe (723). The buffer block (721) is located between the shock-absorbing plate (701) and the battery separator (103), and integrates a storage cavity (722) inside. The storage cavity (722) is filled with hydraulic oil. The buffer blocks (721) in adjacent battery chambers (3) are interconnected through the connecting pipe (723) penetrating the battery separator (103).

5. A lithium battery pack according to claim 4, characterized in that: The pad (724) is fixed to the contact surface of the buffer block (721), and its cross-section is an obtuse triangle with the vertex pointing to the damping plate (701). The position of the pad (724) corresponds to the storage cavity (722), and when it is pressed, it concentrates the pressure to the storage cavity (722).

6. A lithium battery pack according to claim 5, characterized in that: The buffer block (721) has a through hole (7211) in the center for the connecting column (6) to pass through. A hollow ring groove (7212) is provided around the through hole (7211) to absorb the impact kinetic energy. The hollow ring groove (7212) has a built-in shock-absorbing spring (7213) to provide elastic reset function. The buffer block (721) is divided into three parts by the isolation groove (8), the middle part contains a through hole (7211) and a shock-absorbing spring (7213), and the two side parts contain storage cavities (722).

7. A lithium battery pack according to claim 4, characterized in that: The battery separator (103) has a flow channel (10) inside. The two ends of the connecting pipe (723) are respectively fixed to the buffer block (721), the storage cavity (722) and the flow channel (10). The flow channel (10) is coaxially nested with an adaptive throttling component (9).

8. A lithium battery pack according to claim 7, characterized in that: The adaptive throttling assembly (9) includes a fixed ring (901), a double sliding column (902), and a return spring (12). The outer wall of the fixed ring (901) is fixedly connected to the flow channel (10), and the ring body is provided with an array of flow holes (11) in the axial direction. The double sliding column (902) has a T-shaped symmetrical structure. Its small diameter end is dynamically sealed to the inner wall of the fixed ring (901), and its large diameter end is dynamically sealed to the inner wall of the flow channel (10). The reset spring (12) is located between the large diameter end of the sliding column (902) and the end face of the fixed ring (901).

9. A lithium battery pack according to claim 8, characterized in that: The slide column (902) integrates an axially penetrating first flow channel (13) and a radially connected second flow channel (14). The second flow channel (14) includes a central hole (131), a radial inner hole (132), and an array of spiral gradient liquid outlet holes (133). The liquid outlet holes (133) are arranged in axial height difference order along the outer wall of the small diameter end of the slide column (902).

10. A lithium battery pack according to claim 9, characterized in that: During a strong impact, the oil pressure at the impact end increases dramatically, forcing the sliding column (902) to move axially. The inner wall of the fixed ring (901) seals the liquid outlet hole (133) sequentially along the spiral gradient. The oil can only flow through the limited cross-sectional area of ​​the first flow channel (13), and the flow resistance increases dramatically to enhance the buffer stiffness.

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