Integrated battery thermal runaway energy absorption resistor and battery pack

Abstract

The application discloses an integrated battery thermal runaway energy-absorbing resistor and a battery pack. The integrated battery thermal runaway energy-absorbing resistor is used for being integrated on a preset component of the battery pack. The integrated battery thermal runaway energy-absorbing resistor is a laminated body, which comprises a first clamping plate, a second clamping plate and an energy-absorbing laminated body clamped between the first clamping plate and the second clamping plate. The energy-absorbing laminated body comprises a plurality of resistance resistance core plates arranged at intervals. The plurality of resistance resistance core plates are connected in series to form a conductive connection. Adjacent resistance resistance core plates and the energy-absorbing laminated body and the first clamping plate and the second clamping plate are separated by phase change material plates. The application can integrate the energy-absorbing resistor with other structural components in the battery pack from the structure, improve the space utilization and improve the integration degree.

Description

Technical Field

[0001] This invention relates to the field of battery thermal runaway discharge technology, and in particular to an integrated battery thermal runaway energy absorption resistor and battery pack. Background Technology

[0002] The safety of electric vehicle batteries faces ongoing challenges, and battery pack design also faces multiple requirements. These include ensuring the normal operation of electrical components while simultaneously meeting the heat dissipation needs of multiple components; maintaining reliable and stable component installation while optimizing space utilization through compact layout; and integrating various safety detection devices with multifunctional components. In existing battery pack technologies, the resistive elements and structural supports used for thermal runaway discharge are typically designed as independent components, leading to low space utilization, increased weight, and increased system complexity. Furthermore, in current battery pack technologies, when thermal runaway occurs, the BMS (Battery Management System) issues a risk warning and reports the fault, and the system shuts down, but it does not actively address the runaway battery, failing to control the impending runaway.

[0003] Patent application CN117153508A discloses a power battery energy release device and method. The method includes: acquiring a signal indicating thermal runaway of any single cell or module within the power battery; electrically connecting the power battery to a discharge module, causing the power battery to discharge to a maximum state of charge or a lower state of charge where the exothermic reaction is mild under thermal runaway conditions. The solution disclosed in this application can effectively delay the development of thermal runaway within the power battery pack, buying time for occupant escape and subsequent thermal runaway control, while also reducing the destructive force of thermal runaway and improving the safety management capabilities of the power battery.

[0004] Patent application CN113223788A discloses a high-power metal plate resistor, which relates to the field of high-power resistor technology. It features two insulating side plates fixed at both ends of an insulating upper and lower baffle. An insulating intermediate partition is snapped into the middle of the two side plates. Multiple resistor elements are alternately arranged between the intermediate partition and the upper and lower insulating baffles. Each insulating side plate has a lead-out terminal fixed to its inner side, which is connected to the resistor element. The intermediate partition includes a main body with snap-fit ​​interfaces at both ends. This design solves the problem that the use of metal screws and metal supports during assembly reduces the resistor's insulation, and the lack of proper reinforcing ribs for the resistor elements leads to deformation after prolonged operation, compromising safety. Furthermore, the traditional resistor cabinet, lacking a fixed slot, is bulky after assembly and unsuitable for modern mechanical equipment.

[0005] Patent application CN117153508A discloses a grid-type high-power metal resistor, relating to the technical fields of high-precision resistors, energy-saving heat exchange, and energy-saving production process design. The proposed grid-type high-power metal resistor includes a grid-type housing and a metal resistor core. The grid-type housing is formed by connecting a predetermined number of heat sinks, with adjacent heat sinks spaced at predetermined intervals, exposing the heat dissipation surfaces of the heat sinks to the air, forming multiple exposed heat dissipation surfaces. The metal resistor core passes through these exposed heat dissipation surfaces and connects to the heat sinks. Each heat sink provides two exposed heat dissipation surfaces, and the multiple heat sinks provide double the number of exposed heat dissipation surfaces. Air flows directly across the surface of the metal resistor core and the multiple exposed heat dissipation surfaces, greatly enhancing the heat dissipation performance of the high-power metal resistor, achieving an open-type high heat dissipation effect, reducing the thermal load on the resistor core, and extending the service life of the high-power metal resistor. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings and defects of the prior art and provide an integrated battery thermal runaway energy absorption resistor with structural support function. Structurally, the energy absorption resistor is integrated with other structural components in the battery pack, thereby improving space utilization and the degree of integration.

[0007] This invention is achieved through the following technical solution:

[0008] In one aspect, the present invention provides an integrated battery thermal runaway energy absorption resistor for integration onto a pre-defined component of a battery pack. The integrated battery thermal runaway energy absorption resistor is a laminate, comprising a first clamping plate, a second clamping plate, and an energy-absorbing laminate clamped between the first clamping plate and the second clamping plate. The energy-absorbing laminate includes a plurality of spaced-apart resistive core plates connected in series to form a conductive connection. Adjacent resistive core plates are separated from each other, as well as from the first clamping plate, the second clamping plate, and the energy-absorbing laminate, by phase change material plates.

[0009] Preferably, an insulating element is arranged circumferentially between adjacent resistor core plates to separate them from each other, and the insulating element is arranged on the outer side of the outer peripheral wall of the phase change material plate.

[0010] Preferably, the insulating element is a circular element, and there are multiple insulating elements between adjacent resistor core plates, which are arranged circumferentially along the resistor core plates.

[0011] Preferably, the insulating element has pre-formed holes.

[0012] Preferably, the first clamping plate, the second clamping plate, and the stacked body form a stacked structure. The stacked structure is provided by a plurality of locking members arranged along the circumference of the stacked structure and spaced apart near its outer peripheral wall. The locking bolts of the locking members pass through the stacked structure and the coaxially arranged insulating members to lock the stacked structure.

[0013] Preferably, the locking bolt is covered with a support sleeve made of high-temperature resistant insulating material, and the support sleeve separates the locking bolt from the hole of the insulating component.

[0014] Preferably, at least two of the resistor core plates each have a wiring terminal at one end for connecting to the energy absorption circuit.

[0015] Preferably, adjacent resistor core plates are connected in series by welding metal plates.

[0016] Preferably, the preset components of the battery pack are at least one of the following: BMS housing, liquid cooling heat exchange plate, high voltage box BDU housing, and box crossbeam;

[0017] Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the BMS housing, a heat insulation pad is bonded to the surface of the first clamping plate formed by the BMS housing, and then screwed to the BMS.

[0018] Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the liquid cooling heat spreader, the second clamping plate is welded or glued to the liquid cooling heat spreader, or is made into a whole with the liquid cooling heat spreader.

[0019] Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the high-voltage box BDU housing, the first clamping plate is integrated onto the outer shell of the high-voltage box BDU housing;

[0020] Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the box beam, the side of the beam and the second clamping plate are integrated into one piece.

[0021] In another aspect, the present invention provides a battery pack comprising a BMS housing, a liquid-cooled heat exchange plate, a high-voltage box BDU housing, and a box beam, wherein at least one of the BMS housing, the liquid-cooled heat exchange plate, the high-voltage box BDU housing, and the box beam is integrated and fixed with the integrated battery thermal runaway energy absorption resistor.

[0022] The energy-absorbing resistor of this invention is designed with a stacked structure. By filling the spaces between the stacked resistor cores with phase change material plates, when the battery system is about to experience thermal runaway, the energy-absorbing resistor is connected in series with an external circuit to control the battery, actively releasing the battery's energy into the energy-absorbing resistor, reducing the risk of thermal runaway, and effectively converting the heat from the resistor into gas for dissipation. Furthermore, it can be integrated with structural components within the battery pack in a pre-defined manner, serving as a structural support component for the battery. This reduces the number of internal structural components, improves space utilization, and solves the problems of large size and weight of existing energy-absorbing resistor devices, which occupy significant PACK space when placed alone. Simultaneously... Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention.

[0024] Figure 2 This is a front view schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention.

[0025] Figure 3 This is a top view schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention.

[0026] Figure 4 This is the invention Figure 1 A magnified schematic diagram of part A of the integrated battery thermal runaway energy absorption resistor.

[0027] Figure 5 This is a schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention integrated on the BMS housing.

[0028] Figure 6 This is a schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention integrated on a liquid-cooled heat spreader.

[0029] Figure 7 This is a schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention integrated on the high-voltage box (BDU) housing.

[0030] Figure 8 This is a schematic diagram of the integrated battery thermal runaway energy absorption resistor of the present invention integrated on the crossbeam of the housing.

[0031] In the picture:

[0032] 1. Integrated battery thermal runaway energy absorption resistor; 2. First clamping plate; 3. Resistor core plate; 4. Phase change material plate; 5. Metal plate; 6. Second clamping plate; 7. Locking bolt; 8. Support sleeve; 9. Insulating component; 10. BMS housing; 11. Thermal insulation pad; 12. Thermal conductive pad; 13. Liquid cooling heat spreader; 14. BDU housing; 15. Box crossbeam. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific 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.

[0034] See Figure 1As shown in the exemplary embodiment of this application, the integrated battery thermal runaway energy absorption resistor 1 is used to be integrated on a preset component of the battery pack. The integrated battery thermal runaway energy absorption resistor is a laminate, including a first clamping plate 2, a second clamping plate 6, and an energy-absorbing laminate clamped between the first clamping plate and the second clamping plate. The energy-absorbing laminate includes a plurality of spaced-apart resistive core plates 3, which are connected in series to form a conductive connection. Adjacent resistive core plates are separated from each other and from the first clamping plate, the second clamping plate, and the energy-absorbing laminate by a phase change material 4 plate.

[0035] In this application, the resistive core plate 3 is a metal plate or a metal alloy plate, and the integrated battery thermal runaway energy absorption resistor 1 is a high-power metal alloy plate-type stacked resistor. When the BMS in the battery system detects abnormal battery voltage and temperature data, indicating that thermal runaway is about to occur, the BMS reports a fault based on the fault strategy, and the high-voltage circuit of the normally operating system is immediately disconnected to avoid serious impact caused by a short circuit in the battery pack. At the same time, the BMS controls the positive and negative terminals of the battery about to runaway to discharge it through the high-voltage circuit of the series energy absorption resistor. The energy absorption resistor starts to work, absorbing the electrical energy released by the battery and converting it into resistive heat. When the integrated battery thermal runaway energy absorption resistor 1 is subjected to large power consumption, heat dissipation is achieved by filling the phase change material plate 4 between the resistive core plate 3 and the resistive core plate, thereby avoiding the problem of damage due to overheating.

[0036] In the specific design, calculations are performed based on the energy released by multiple cells in the battery system, using the heat formula. (where c is the specific heat capacity of the resistor), because the released energy Q is relatively large, the time t is relatively short, and the external circuit discharge current I is relatively large, therefore the resistance value is... Smaller.

[0037] Because metal alloy resistors absorb a relatively large amount of energy Q, the temperature rise ∆T needs to be controlled within a certain range to avoid overheating and damage. Therefore, the quality of the resistor is crucial. Larger.

[0038] Since the resistance value is determined by the material and geometric dimensions, based on the resistance formula... ρ is resistivity, L is length, and A is cross-sectional area. It can be deduced that when the resistance value R is smaller and L is constant, the cross-sectional area A is larger, that is, the width and thickness of the resistor are larger.

[0039] Therefore, considering the weight of the battery pack, this application preferably limits the thickness H of the resistive core plate of the metal plate resistor to within 3mm, and, considering the battery pack installation space, limits the width W of the resistive core plate of the metal plate resistor to within 100mm. For applications with higher battery energy, the energy absorption requirements can be met by increasing the length L of the resistive core plate of the metal plate resistor. Considering the installation boundary of the energy absorption resistor, L should not exceed 1m.

[0040] Regarding phase change material plates, since phase change materials require rapid heat conversion at high temperatures and the amount of heat converted is high, the latent heat value of the solid-liquid phase change material is 220. The latent heat value of solid-gas phase change materials is 2000. By comparing different materials and calculating the maximum energy that the energy-absorbing resistor needs to absorb within the battery pack, a solid-gas phase change material with no risk of leakage and a large latent heat value is selected. Based on the encapsulation process, latent heat performance, and volume change after heat absorption of the phase change material, the optimal thickness of the phase change material within the battery pack is typically designed to be 1mm to 10mm.

[0041] The phase change material plate can be formed by encapsulating a phase change material in a plate-shaped container. The phase change material is a solid-gas phase change material or a similar material, such as at least one of metal halides, dry ice, or inorganic composite phase change materials. The plate-shaped container is a metal material or a thermally conductive metal material, such as at least one of aluminum alloy, SUS304 stainless steel alloy, or copper-aluminum composite alloy. The resistor core plate is a metal plate or an alloy metal plate, such as at least one of aluminum alloy, SUS304 stainless steel alloy, or copper-aluminum composite alloy.

[0042] In one embodiment, an insulating member 9 is arranged circumferentially between adjacent resistor core plates to separate the stacked resistor core plates. The insulating member is arranged on the outer side of the outer peripheral wall of the phase change material plate. Preferably, the insulating member is circular, and multiple insulating members are arranged circumferentially between adjacent resistor core plates. More preferably, the insulating member has pre-formed holes, similar in shape to an insulating gasket, and its material can be plastic. In this embodiment, insulating members 9 are filled between each layer of resistor cores at the location where the locking bolt 7 passes through for support. When the battery pack is working normally, the insulating members will not be affected by high temperature and current impact, and the support of the insulating members also provides heat dissipation space for each layer of resistor core plates.

[0043] In one embodiment, the thickness of the insulating element 9 between the resistor core plates is typically designed to be 2mm to 4mm for support, which determines that the gap h between each layer of resistor core plates is between 2mm and 4mm.

[0044] In one embodiment, the first clamping plate, the second clamping plate, and the stacked body form a stacked structure. The stacked structure is provided by a plurality of locking members arranged circumferentially along the stacked structure and spaced apart near its outer peripheral wall. The locking bolts 7 of the locking members pass through the stacked structure and the coaxially arranged insulating member 9 to lock the stacked structure.

[0045] In one embodiment, the locking bolt is covered by a support sleeve 8 made of high-temperature resistant insulating material, preferably mica. The support sleeve separates the locking bolt from the hole in the insulating component. The support sleeve 8, which passes through the locking bolt 7 and wraps around the insulating component, serves to ensure the structural strength of the energy-absorbing resistor even after a large current flows through it or the plastic insulating component fails under high-temperature conditions, due to its high-temperature resistance and arc impact resistance.

[0046] In one embodiment, at least two of the resistor core plates each have a wiring terminal at one end for connecting to the energy absorption circuit.

[0047] In one embodiment, adjacent resistor core plates are connected in series by a welded metal plate 5, which can be an alloy plate or other non-alloy plate material.

[0048] Due to the large size and weight of the resistor device, this application proposes to integrate the stacked energy-absorbing resistor of this application with other structural components within the battery pack. In some embodiments, the preset components of the battery pack are at least one of the BMS housing, liquid-cooled heat spreader, high-voltage box BDU housing, and box beam; in this application, the first clamping plate and / or the second clamping plate can be one or two components or sidewalls of the preset components that can function as clamping plates, that is, one or two components, plates, or sides of the preset components that can function as clamping plates can be used simultaneously as the first clamping plate and / or the second clamping plate, thereby realizing the integration of the energy-absorbing resistor of this application with the battery pack components.

[0049] When the energy-absorbing resistor is integrated with the BMS housing 10, such as Figure 5 As shown, for the flat-plate stacked resistor structure, the BMS housing is used as the second clamping plate. A heat insulation pad 11 is attached above the first clamping plate 2 for insulation and heat insulation. The BMS is installed on the first clamping plate 2 by riveting studs. When the battery pack is working normally, the energy-absorbing resistor only serves as a structural support and does not generate heat. When the energy-absorbing resistor is absorbing heat, the heat insulation pad 11 isolates the heat of the resistor, preventing the high temperature from affecting the BMS. At the same time, to avoid electromagnetic interference from the resistor to the BMS, the first clamping plate housing of the resistor can be made of a metal composite alloy. In this integration method with the BMS housing 10, a heat-conducting pad 12 is attached to the bottom of the energy-absorbing resistor. In this way, through the phase change material and the bottom heat-conducting pad, the heat of the resistor can be quickly conducted to the inside of the battery box and the bottom of the box.

[0050] like Figure 6As shown, when integrating the energy-absorbing resistor with the liquid-cooled vapor chamber 13, the second clamping plate 6 of the energy-absorbing resistor is welded or glued to the upper vapor chamber of the liquid-cooled plate, or the second clamping plate 6 of the energy-absorbing resistor and the vapor chamber of the liquid-cooled plate are made into a single unit. The vapor chamber also serves as the second clamping plate 6. The energy-absorbing resistor does not need to be bolted or fixed inside the housing. When the energy-absorbing resistor is working, the heat of the resistor can be directly conducted to the liquid-cooled plate, and the heat is quickly removed by the liquid-cooled plate or coolant. Furthermore, by combining or connecting in the aforementioned manner, the installation and heat dissipation performance requirements of the energy-absorbing resistor and structural components can still be met.

[0051] like Figure 7 As shown, when integrating the energy-absorbing resistor with the high-voltage box BDU housing 14, since the battery pack BDU is usually modularly designed, including an upper BDU housing, a lower BDU housing, and internal high-voltage electrical components, the lower BDU housing typically needs to support the electrical components, ensure the stability of the BDU's mechanical performance, and provide insulation protection. Therefore, in this application, the first clamping plate 2 of the energy-absorbing resistor is integrated onto the lower BDU housing, i.e., the lower BDU housing is used as the first clamping plate. The first clamping plate 2 is made of a high-strength plastic composite material, which needs to ensure high structural strength and the ability to be processed into irregular shapes. A thermal pad or phase change material is selected between the resistive core plate of the energy-absorbing resistor and the lower BDU housing for heat conduction; the plate-type stacked energy-absorbing resistor can act as a heat sink for the high-voltage box BDU during normal operation of the battery pack, realizing active heat dissipation for the high-voltage box BDU.

[0052] like Figure 8 As shown, when integrating the energy-absorbing resistor with the box beam 15, the width and thickness of the plate resistor can be reduced and its length increased based on the heat formula when the energy required to be absorbed within the battery pack is high, thus designing the resistor structure as a flattened form. Then, the flattened metal plate resistor is mounted sideways on the side of the box beam, and the side of the beam is integrated with the second clamping plate 6, using the side of the beam as the second clamping plate. A thermal pad or phase change material is used for heat conduction between the resistor core plate and the box beam. In this integration method, the second clamping plate can be made of metal. The metal plate resistor structure is stable and has high strength; the side-mounted method saves space within the battery pack and improves the structural strength of the beam. When the energy-absorbing resistor is working, the heat from the resistor can be dissipated through the cavity of the box beam.

[0053] Embodiments of this application also provide a battery pack, including a BMS housing, a liquid-cooled heat spreader, a high-voltage box BDU housing, and a box beam. At least one of the integrated battery thermal runaway energy absorption resistors in the BMS housing, liquid-cooled heat spreader, high-voltage box BDU housing, and box beam is integrated and fixed. Specifically, the integration method of at least one of the integrated battery thermal runaway energy absorption resistors in the BMS housing, liquid-cooled heat spreader, high-voltage box BDU housing, and box beam is described in this application. Figures 5-8 The structure shown is accompanied by the relevant specification content of this application.

[0054] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0055] Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of the equivalents of the claims be included within the invention.

[0056] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An integrated battery thermal runaway energy absorption resistor, characterized in that, The integrated battery thermal runaway energy absorption resistor is a laminated body used for integration into a pre-set component of a battery pack. It includes a first clamping plate, a second clamping plate, and an energy absorption laminated body clamped between the first clamping plate and the second clamping plate. The energy absorption laminated body includes multiple spaced-apart resistor core plates. The multiple resistor core plates are connected in series to form a conductive connection. Adjacent resistor core plates are separated from each other and from the first clamping plate, the second clamping plate, and the energy absorption laminated body by phase change material plates.

2. The integrated battery thermal runaway energy absorption resistor according to claim 1, characterized in that, An insulating element is arranged along the circumference of the adjacent resistor core plates to separate them from each other. The insulating element is arranged on the outer side of the outer peripheral wall of the phase change material plate.

3. The integrated battery thermal runaway energy absorption resistor according to claim 2, characterized in that, The insulating component is circular, and there are multiple insulating components between adjacent resistor core plates, which are arranged circumferentially along the resistor core plates.

4. The integrated battery thermal runaway energy absorption resistor according to claim 2, characterized in that, The insulating component has pre-drilled holes.

5. The integrated battery thermal runaway energy absorption resistor according to claim 2, characterized in that, The first clamping plate, the second clamping plate, and the stacked body form a stacked structure. The stacked structure is provided by a plurality of locking members arranged along the circumference of the stacked structure and spaced apart near its outer peripheral wall. The locking bolts of the locking members pass through the stacked structure and the coaxially arranged insulating members to lock the stacked structure.

6. The integrated battery thermal runaway energy absorption resistor according to claim 5, characterized in that, The locking bolt is covered by a support sleeve made of high-temperature resistant insulating material, which separates the locking bolt from the hole in the insulating component.

7. The integrated battery thermal runaway energy absorption resistor according to claim 1, characterized in that, At least two of the resistor core plates each have a wiring terminal at one end for connecting to the energy absorption circuit.

8. The integrated battery thermal runaway energy absorption resistor according to claim 1, characterized in that, Adjacent resistor core plates are connected in series by welding metal plates.

9. The integrated battery thermal runaway energy absorption resistor according to claim 1, characterized in that, The battery pack's pre-defined components include at least one of the following: BMS housing, liquid-cooled heat exchange plate, high-voltage box BDU housing, and box beam. Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the BMS housing, a heat insulation pad is bonded to the surface of the first clamping plate formed by the BMS housing, and then screwed to the BMS. Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the liquid cooling heat spreader, the second clamping plate is welded or glued to the liquid cooling heat spreader, or is made into a whole with the liquid cooling heat spreader. Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the high-voltage box BDU housing, the first clamping plate is integrated onto the outer shell of the high-voltage box BDU housing; Preferably, when the integrated battery thermal runaway energy absorption resistor is integrated with the box beam, the side of the beam and the second clamping plate are integrated into one piece.

10. A battery pack, comprising a BMS housing, a liquid-cooled heat exchange plate, a high-voltage box BDU housing, and a box beam, wherein at least one of the BMS housing, the liquid-cooled heat exchange plate, the high-voltage box BDU housing, and the box beam is integrated and fixed with the integrated battery thermal runaway energy absorption resistor according to any one of claims 1-9.

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