A safety battery pack

Abstract

This invention relates to a safety battery pack, specifically in the field of batteries. The pack includes a casing, a battery module installed within the casing, a liquid cooling structure located at the bottom of the battery module for cooling the battery module, and a fire extinguishing mechanism for extinguishing a fire in the battery module. The fire extinguishing mechanism includes an exhaust fan blowing air onto one side of the battery module, a first safety structure located at ignition points at both ends of the battery module for fire extinguishing, and a second safety structure used in conjunction with the exhaust fan to assist the first safety structure in fire extinguishing. The exhaust fan works in conjunction with the liquid cooling structure to cool the battery module. The first safety structure includes a fire extinguishing airbag that releases extinguishing gas to reduce the oxygen content at the ignition point after a fire starts. The second safety structure includes a fire extinguishing ball that, after a fire starts, drives the exhaust fan to rotate and roll towards the ignition point, releasing its internal extinguishing gas. This application improves the safety of electrochemical energy storage batteries.

Description

Technical Field

[0001] This invention relates to the field of battery safety technology, and in particular to a safe battery pack applicable to power batteries, energy storage batteries and other electrochemical battery systems. Background Technology

[0002] With the development of new energy technologies, lithium-ion batteries, sodium-ion batteries, and other secondary batteries are widely used in electric vehicles, energy storage systems, and various electrical devices. These batteries generate heat during charging and discharging. When this heat accumulates and cannot be dissipated in time, it may cause thermal runaway, and in severe cases, even lead to fire or explosion.

[0003] Existing battery packs typically dissipate heat through liquid cooling or air cooling structures. However, when a battery experiences thermal runaway or catches fire, traditional cooling systems often fail due to power outages, making it difficult to maintain a sustained cooling effect. Furthermore, most battery packs lack effective automatic fire suppression mechanisms, often requiring reliance on external fire extinguishing equipment. This not only results in delayed response but also increases the risk of fire spreading and triggering chain reactions, posing significant safety hazards.

[0004] Therefore, how to achieve active heat dissipation and automatic fire extinguishing, and suppress the spread of thermal runaway, in the event of abnormal temperature rise or even fire in the battery pack, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] To improve the safety of electrochemical energy storage batteries, this invention provides a safe battery pack.

[0006] This invention provides a safe battery pack, employing the following technical solution: A safety battery pack includes a housing, a battery module installed inside the housing, a liquid cooling structure disposed at the bottom of the battery module for cooling the battery module, and a fire extinguishing mechanism for extinguishing fire when the battery module catches fire. The fire extinguishing mechanism includes an exhaust fan that blows air on one side of the battery module, a first safety structure located at the ignition points at both ends of the battery module for fire extinguishing, and a second safety structure used in conjunction with the exhaust fan to assist the first safety structure in fire extinguishing. The exhaust fan works in conjunction with the liquid cooling structure to cool the battery module. The first safety structure includes a fire extinguishing airbag, which releases fire extinguishing gas after a fire starts to reduce the oxygen content at the ignition point. The second safety structure includes a fire extinguishing ball, which drives the exhaust fan to rotate and roll towards the ignition point after a fire starts to release the fire extinguishing gas inside.

[0007] By adopting the above technical solutions, the fire extinguishing mechanism can target the ignition point inside the battery pack to effectively prevent dangerous situations such as explosions caused by continuous combustion of the battery pack, thus improving safety. The exhaust fan, in conjunction with the liquid cooling structure, continuously cools the battery module, preventing the battery module from being at high temperatures for a long time and reducing heat accumulation. The first and second safety structures can extinguish and cool the ignition point when a fire breaks out inside the battery pack, further improving the safety of the battery pack.

[0008] Optionally, the first safety structure further includes a support tube rotatably disposed inside the outer shell, a protective shell disposed on the support tube for storing the fire extinguishing airbag, a first airbag fixed to the bottom of the protective shell and expanding when heated, a squeezing claw rotatably mounted on the protective shell and rotating in conjunction with the expansion of the first airbag, and a squeezing rod cooperating with the squeezing claw to squeeze the fire extinguishing airbag out of the protective shell. The top of the protective shell has a through hole for the fire extinguishing airbag to be extruded; The extrusion rod is rotatably installed inside the protective housing. One side of the extrusion rod abuts against the extrusion claw, and the other side abuts against the fire extinguishing airbag to drive the fire extinguishing airbag to have a tendency to extrude towards the through hole.

[0009] By adopting the above technical solution, the first safety structure uses the fire extinguishing airbag to extinguish the fire from the inside. Before the fire starts, the fire extinguishing airbag is stored in the protective shell to prevent the fire extinguishing airbag from being exposed too early and damaged. Through the cooperation of the first airbag that expands when heated and the squeezing claw, the fire extinguishing airbag can be squeezed out of the protective shell during the continuous heating process, and can automatically expand and contract according to the environment inside the battery pack.

[0010] Optionally, the support tube is provided with a support structure that supports the support tube and drives the support tube to tilt toward the fire point when heated. The support structure includes a snap ring sleeved on the support tube, a support rod snapped into the snap ring and easily deformed and bent by heat, and a snap structure for fixing the support rod in the snap ring. The snap structure includes a snap ball for fixing the support rod and a first spring for pressing the snap ball against the support rod. The snap ball has a snap groove to prevent the snap ball from falling off. The support tube tilts toward the ignition point when the support rod is heated and bent.

[0011] By adopting the above technical solution, the support structure plays a supporting role when there is no fire. After the fire starts, the support structure is heated and deformed, losing its supporting role. This causes the support pipe to tilt towards the side closer to the fire point, adaptively adjusting and selecting the direction of the fire point, tilting towards the side with higher temperature, so that the gas of the fire extinguishing airbag is preferentially sprayed at the fire point or the side with higher temperature.

[0012] Optionally, the first safety structure further includes clamping claws for holding the fire extinguishing airbag that has been squeezed out of its protective shell, and a connecting structure is provided between the squeezing claws and the clamping claws. The connection structure includes a first connecting plate and a second connecting plate rotatably connected to the extrusion claw. The second connecting plate connects the first connecting plate and the clamping claw to drive the clamping claw to rotate when the extrusion claw rotates.

[0013] By adopting the above technical solution, the connecting structure can simultaneously control the squeezing claw to squeeze the fire extinguishing airbag out of the protective shell while the first airbag expands due to heat, and simultaneously drive the clamping claw to clamp the fire extinguishing airbag that has been squeezed out of the protective shell. This avoids the fire extinguishing airbag from shaking in high-temperature environments, improves stability, and provides a basis for puncturing the fire extinguishing airbag to release the fire extinguishing gas.

[0014] Optionally, the gripping claw is provided with a release structure for releasing fire extinguishing gas; The release structure includes a spike that extends and retracts within the clamping claw near one end of the fire extinguishing airbag and is used to puncture the fire extinguishing airbag after it is squeezed out of its protective shell; a second spring that is slidably installed within the clamping claw and has a tendency to push the spike out of the clamping claw; a collar that is sleeved outside the spike and prevents the spike from extending out of the clamping claw; a third spring that has a tendency to extend the collar and lock the spike; and a push plate that is slidably installed within the clamping claw and is controlled by a second connecting plate to push the collar back.

[0015] By adopting the above technical solution, the release structure is used to release the extinguishing gas in the fire extinguishing airbag. During the process of the clamping claw holding the fire extinguishing airbag, as the first airbag continues to expand and the ambient temperature rises, the second connecting plate pushes the push plate to retract the collar so that the spikes extend out and, together with the clamping claw, clamp and puncture the fire extinguishing airbag.

[0016] Optionally, the exhaust fan includes a shaft fixedly mounted on the inner wall of the housing, a rotating ring rotatably mounted on the shaft, a connecting seat slidably mounted on the rotating ring, and fan blades fixed on the connecting seat and distributed in a circumferential array. The rotating ring is provided with a connecting groove for a matching connecting seat, and the fan blade has a receiving arc-shaped channel for receiving and guiding the fire extinguishing ball.

[0017] By adopting the above technical solution, the exhaust fan can be detachably installed on the outer casing, and the shape and number of fan blades can be changed according to different needs. It can be adapted to different environments and is also convenient for disassembly and cleaning of the fan.

[0018] Optionally, the liquid cooling structure includes a liquid cooling plate containing coolant. The liquid cooling plate includes a serpentine LCP cooling channel disposed at the bottom of the battery module and a cooling channel vertically disposed in the LCP cooling channel for supplying cool air to the exhaust fan. The cooling channel is located between the exhaust fan and the battery module. The LCP cooling channel includes a heat collection layer channel for conducting heat from the battery cell and allowing coolant to flow, and a heat transfer layer channel for dissipating heat from the coolant.

[0019] By adopting the above technical solution, the liquid cooling plate continuously cools the battery module, preventing the battery module from accumulating heat and increasing the probability of fire. The cooling channel, together with the exhaust fan, blows away the cold air and cools the battery module, improving the safety of the battery pack.

[0020] Optionally, the second safety structure includes a rolling chamber located at the top of the housing for storing the fire extinguishing ball. The rolling chamber has an opening for the fire extinguishing ball to roll onto the fan blades. A second airbag is provided inside the rolling chamber to expand when heated to compress the fire extinguishing ball. An elastic membrane is provided on the opening to prevent the fire extinguishing ball from falling. Barbs are provided on the opening for puncturing the elastic membrane. When the second airbag is heated, it compresses the fire extinguishing ball until the elastic membrane bulges downward and is punctured by barbs. The fire extinguishing ball then falls out of the opening onto the fan blades of the exhaust fan to start the exhaust fan.

[0021] By adopting the above technical solution, the exhaust fan cannot dissipate heat after the power is cut off after the fire starts. At this time, the second airbag at the top of the outer shell expands due to heat and pressurizes the fire extinguishing ball out of the rolling chamber. During the fall of the fire extinguishing ball, it triggers the exhaust fan to start dissipating heat.

[0022] Optionally, the second safety structure further includes a rolling channel for the fire extinguishing ball to roll after falling, the rolling channel pointing towards the first safety structure, and two exhaust fans are provided. The rolling channels are respectively inclined on both sides of the outer shell and allow the fire extinguishing ball to roll to both sides after falling. The fire extinguishing ball includes a dry ice core and a shell that melts upon heating. As the fire extinguishing ball rolls toward the ignition point in the rolling channel, its shell melts due to heat, exposing a dry ice core for further heat dissipation.

[0023] By adopting the above technical solution, the fire extinguishing ball rolls towards the first safety structure after falling. During the rolling process, the shell of the fire extinguishing ball is heated and melted, exposing the dry ice core of the fire extinguishing ball. The carbon dioxide gas generated by the dry ice core can also play a fire extinguishing role.

[0024] Optionally, the battery module includes battery cells arranged in series, a heat insulation pad disposed between the battery cells for insulation and heat insulation, a buffer cotton disposed at both ends of the battery cells in series for buffering the thermal expansion of the battery cells, a Mylar sheet disposed outside the buffer cotton for preventing leakage of the battery cells, an insulating sheet disposed on the top of the battery cells for preventing leakage between battery modules, a cable tie sleeved on the outside of the battery cells for preventing the battery cells from loosening, and an aluminum end plate disposed between the cable tie and the Mylar sheet for protecting the battery cells from deformation.

[0025] By adopting the above technical solutions, the battery module uses insulating sheets, heat insulation pads, Mylar sheets, etc. to prevent leakage and heat insulation between cells. Cable ties are used to fix the cells to prevent them from falling off, which improves stability. At the same time, cushioning cotton is provided to prevent deformation caused by thermal expansion of the cells, which improves the safety of the battery module.

[0026] In summary, this application includes at least one of the following beneficial technical effects: By using fire extinguishing equipment to target the ignition point inside the battery pack, the dangers of continuous combustion leading to explosions and other dangerous situations are effectively prevented, thus improving safety. The exhaust fan, in conjunction with the liquid cooling structure, continuously cools the battery module, preventing it from being at high temperatures for extended periods and reducing heat accumulation. The first and second safety structures extinguish and cool the fire at the ignition point when a fire breaks out inside the battery pack, thus improving the safety of the battery pack. Attached Figure Description

[0027] Figure 1 This is a structural diagram of a safety battery pack; Figure 2 This is a cross-sectional view of a safety battery pack; Figure 3 This is a schematic diagram of the first insurance structure; Figure 4 This is a structural diagram of the supporting structure; Figure 5 This is a schematic diagram of the release structure; Figure 6 This is a structural diagram of an exhaust fan; Figure 7 This is a schematic diagram of the liquid cooling structure; Figure 8 This is a schematic diagram of an open structure; Figure 9 This is an exploded view of the battery module.

[0028] The parts referred to by the numbers in the attached diagrams are as follows: 1. Outer shell; 2. Battery module; 3. Liquid cooling structure; 4. Panel; 5. Fire extinguishing mechanism; 6. Exhaust fan; 7. First safety structure; 8. Second safety structure; 9. Fire extinguishing airbag; 10. Support tube; 11. Protective shell; 12. Through hole; 13. First airbag; 14. Compression claw; 15. Clamping claw; 16. Compression rod; 17. Connecting structure; 18. First connecting plate; 19. Second connecting plate; 20. Supporting structure; 21. Snap-fit ​​ring; 22. Support rod; 23. Snap-fit ​​structure; 24. Snap-fit ​​ball; 25. First spring; 26. Telescopic groove; 27. Snap-fit ​​groove; 28. Release structure; 29. ​​Spike; 30. Second spring; 31. Sleeve 32. Ring; 33. Third spring; 34. Push plate; 35. Spiked channel; 36. Ring channel; 37. Push channel; 38. Shaft; 39. Rotary ring; 40. Connecting seat; 41. Fan blade; 42. Connecting groove; 43. Receiving arc-shaped channel; 44. Motor; 45. Liquid cooling plate; 46. LCP cooling channel; 47. Cooling channel; 48. Heat collection layer channel; 49. Heat transfer layer channel; 50. Rolling chamber; 51. Rolling channel; 52. Fire extinguishing ball; 53. Second airbag; 54. Opening; 55. Elastic membrane; 56. Barbs; 57. Dry ice core; 58. Shell; 59. Battery cell; 60. Heat insulation pad; 61. Buffer cotton; 62. Mylar sheet; 63. Insulating sheet; 64. Cable tie; 65. Aluminum end plate. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0030] This invention discloses a safe battery pack.

[0031] Reference Figure 1 and Figure 2 A safety battery pack includes a housing 1, a battery module 2, a liquid cooling structure 3, a panel 4, and a fire extinguishing mechanism 5. The housing 1 is located above the battery module 2, and the liquid cooling structure 3 is located below the battery module 2. The housing 1 encloses the battery module 2 and the fire extinguishing mechanism 5, and the housing 1 is fixed to the liquid cooling structure 3 by bolts. The liquid cooling structure 3 is used to cool the battery module 2. The fire extinguishing mechanism 5 is located inside the battery pack and extinguishes the fire when the battery module 2 catches fire. The panel 4 is provided with a switch button and connected to a wire.

[0032] Reference Figure 2The fire extinguishing mechanism 5 includes an exhaust fan 6, a first safety structure 7, and a second safety structure 8. The exhaust fan 6 is located on one side of the battery module 2 and works with the liquid cooling structure 3 to blow cold air to cool the battery module 2. The first safety structure 7 is located at the ignition point at the other end of the battery module 2, which is mostly the wire connection point, i.e., near the panel 4. In this embodiment, the first safety structure 7 is located near the panel 4 for easy and timely fire extinguishing. The second safety structure 8 is located on the top of the outer casing 1. The second safety structure 8 works in conjunction with the exhaust fan 6 and can also assist the first safety structure 7 in fire extinguishing.

[0033] Reference Figure 3 The first safety structure 7 includes a fire extinguishing airbag 9, a support tube 10, a protective shell 11, a first airbag 13, a squeezing claw 14, a clamping claw 15, and a squeezing rod 16. The fire extinguishing airbag 9 releases extinguishing gas after ignition to reduce the oxygen content at the ignition point. The support tube 10 is rotatably mounted inside the shell 1, with its bottom connected to the interior of the shell 1 by a ball joint, rotating in both directions. The protective shell 11 is mounted on the support tube 10, and the fire extinguishing airbag 9 is stored and protected within it. The first airbag 13 is fixed to the bottom of the protective shell 11 by a metal wire. The gas in the first airbag 13 expands when heated; common gases with significant thermal expansion and contraction, such as helium and nitrogen, can be used. The squeezing claw 14 is rotatably mounted on the protective shell 11 and rotates in conjunction with the first airbag 13. The squeezing rod 16 is located inside the protective shell 11. The top of the protective shell 11 has a through hole 12 for the extrusion of the fire extinguishing airbag 9. One side of the extrusion rod 16 abuts against the extrusion claw 14, and the other side of the extrusion rod 16 abuts against the fire extinguishing airbag 9. The extrusion rod 16 drives the fire extinguishing airbag 9 to tend to squeeze towards the through hole 12. In this embodiment, the first airbag 13, the extrusion claw 14, and the extrusion rod 16 are symmetrically arranged on both sides of the protective shell 11 and the support tube 10. After the first airbag 13 expands due to heat, it pushes the extrusion claw 14 to rotate. The extrusion claw 14 rotates and pushes the extrusion rod 16 inside the protective shell 11 to squeeze inward. The extrusion rod 16 squeezes the fire extinguishing airbag 9 out of the protective shell 11. The clamping claw 15 is rotatably mounted on the protective shell 11 and is used to clamp the fire extinguishing airbag 9 that has been squeezed out of the protective shell 11. A connecting structure 17 is provided between the extrusion claw 14 and the clamping claw 15.

[0034] Reference Figure 3 and Figure 4 A support structure 20 is provided on the support pipe 10. The support structure 20 supports the support pipe 10, and when heated, the support structure 20 drives the support pipe 10 to tilt towards the ignition point.

[0035] Reference Figure 4The support structure 20 includes a snap ring 21, a support rod 22, and a snap structure 23. The snap ring 21 is sleeved on the support tube 10, and the support rod 22 is snapped into the snap ring 21 by the snap structure 23. When the support rod 22 is heated, it is easy to deform and bend, losing its supporting function. The snap structure 23 is used to fix the support rod 22 in the snap ring 21.

[0036] Reference Figure 4 The snap-fit ​​structure 23 includes a snap-fit ​​ball 24 and a first spring 25. The snap-fit ​​ball 24 is used to fix the support rod 22. The snap-fit ​​ring 21 has a telescopic groove 26 for the snap-fit ​​ball 24 to extend and retract. The first spring 25 is also disposed in the telescopic groove 26. The first spring 25 has a tendency to press the snap-fit ​​ball 24 tightly against the support rod 22. The snap-fit ​​ball 24 has a snap-fit ​​groove 27 to prevent the snap-fit ​​ball 24 from falling out of the snap-fit ​​ring 21. In this embodiment, a pair of snap-fit ​​structures 23 are symmetrically arranged. The snap-fit ​​structures 23 are used to initially fix the support rod 22. When one side of the support rod 22 is heated and bent, the support tube 10 loses support and tilts to the side of the bent support rod 22. At this time, the other side of the support rod 22 is subjected to the tilting force, causing the support rod 22 to fall out of the snap-fit ​​ring 21, so that the support tube 10 completely falls in the direction of heating.

[0037] Reference Figure 3 The connecting structure 17 includes a first connecting plate 18 and a second connecting plate 19. The first connecting plate 18 is rotatably connected to the compression claw 14, and the second connecting plate 19 is rotatably mounted on the first connecting plate 18. When the compression claw 14 rotates due to the expansion of the first airbag 13, it drives the clamping claw 15 to rotate through the first connecting plate 18 and the second connecting plate 19 to clamp the fire extinguishing airbag 9 that has been squeezed out of the protective shell 11.

[0038] Reference Figure 3 and Figure 5The clamping claw 15 is equipped with a release structure 28, which is used to release the extinguishing gas in the fire extinguishing airbag 9. The release structure 28 includes a spike 29, a second spring 30, a collar 31, a third spring 32, and a pusher plate 33. The clamping claw 15 has a spike channel 34 for the extension and retraction of the spike 29, a collar channel 35 for the extension and retraction of the collar 31, and a pusher channel 36 for the sliding of the pusher plate 33. The spike 29 extends and retracts within the clamping claw 15 at one end near the fire extinguishing airbag 9, and the spike 29 is used to puncture the fire extinguishing airbag 9 that has been squeezed out of the protective shell 11 and release the extinguishing gas. The second spring 30 is slidably installed in the spike channel 34 within the clamping claw 15, and the second spring 30 has a tendency to always drive the spike 29 to extend out of the spike channel 34. A collar 31 is fitted onto the spike 29 and serves to limit the spike 29's extension through the spike channel 34. The collar 31 is telescopically mounted within a collar channel 35. The collar 31 is connected to and controlled by a push plate 33 to slide within the collar channel 35. A third spring 32 is disposed within the collar channel 35 and has a tendency to consistently press the collar 31 against the spike 29. The push plate 33 is slidably mounted within a push channel 36 in the clamping jaw 15, and the push plate 33 is controlled by a second connecting plate 19 to push the collar 31 back into the collar channel 35.

[0039] Reference Figure 2 and Figure 6 The exhaust fan 6 includes a shaft 37, a rotating ring 38, a connecting seat 39, and fan blades 40. The shaft 37 is fixedly mounted on the inner wall of the outer casing 1, the rotating ring 38 is rotatably mounted on the shaft 37, the connecting seat 39 is slidably mounted on the rotating ring 38, and the fan blades 40 are fixed on the connecting seat 39 and arranged in a circumferential array. The rotating ring 38 has a connecting groove 41 that mates with the connecting seat 39, and the fan blades 40 have an arc-shaped channel 42 for receiving and guiding the fire extinguishing ball 51. When the battery pack is not on fire, the exhaust fan 6 can be controlled by an external motor 43.

[0040] Reference Figure 2 The liquid cooling structure 3 includes a liquid cooling plate 44, in which coolant flows. The liquid cooling plate 44 uses two LCP channels and a lightweight aluminum plate. Under the conditions that the aluminum plate thickness is 4mm and the coolant velocity is 0.275m / s, the maximum temperature and temperature difference of the battery module are controlled below 31.80℃ and 3.70℃, respectively. At the same time, this structure accounts for only 16.4% of the module weight, achieving lightweight and high cooling performance, and is suitable for large battery modules.

[0041] Reference Figure 7The liquid cooling plate 44 includes an LCP cooling channel 45 and a cooling dissipation channel 46. The LCP cooling channel 45 is located at the bottom of the battery module 2 and is serpentine in shape. The cooling dissipation channel 46 is vertically arranged on the LCP cooling channel 45 and is used for supplying cool air to the exhaust fan 6. The LCP cooling channel 45 includes a heat collection layer channel 47 and a heat transfer layer channel 48. The heat collection layer channel 47 is used to conduct heat from the battery cell 58 and to allow coolant to circulate, while the heat transfer layer channel 48 is used to dissipate heat from the coolant.

[0042] Reference Figure 2 and Figure 8 The second safety structure 8 includes a rolling chamber 49, a rolling channel 50, a fire extinguishing ball 51, and a second airbag 52. The rolling chamber 49 is located at the top inside the outer casing 1 and stores the fire extinguishing ball 51. The rolling chamber 49 has an opening 53 located above the exhaust fan 6, allowing the fire extinguishing ball 51 to roll onto the fan blades 40. The bottom of the rolling chamber 49 is inclined downwards towards the exhaust fan 6 to facilitate the fire extinguishing ball 51 rolling onto the fan blades 40. The second airbag 52 is located inside the rolling chamber 49 on the side away from the exhaust fan 6. The second airbag 52 expands when heated to compress the fire extinguishing ball 51. An elastic membrane 54 is provided on the opening 53 to prevent the fire extinguishing ball 51 from falling, and barbs 55 are provided on the opening 53 for puncturing the elastic membrane 54. When the second airbag 52 is heated, it compresses the fire extinguishing ball 51 until the elastic membrane 54 bulges downward and is punctured by the barbs 55. The fire extinguishing ball 51 falls out from the opening 53 onto the fan blades 40 of the exhaust fan 6 to drive the exhaust fan 6 to start.

[0043] Reference Figure 2 and Figure 8 The rolling channel 50 is used to allow the fire extinguishing ball 51 to roll after falling and guide the fire extinguishing ball 51 to roll towards the first safety structure 7. In this embodiment, there are two exhaust fans 6, and the rolling channels 50 are respectively inclinedly arranged on both sides of the outer casing 1, and the rolling channels 50 allow the fire extinguishing ball 51 to roll from both sides towards the first safety structure 7 after falling.

[0044] Reference Figure 8 The fire extinguishing ball 51 includes a dry ice core 56 and a shell 57. The shell 57 melts when exposed to high temperatures. In this embodiment, all objects that melt when heated are made of thermoplastic materials, wax materials, etc. When the fire extinguishing ball 51 rolls toward the fire point in the rolling channel 50, the shell 57 melts due to heat, exposing the dry ice core 56 for further heat dissipation.

[0045] Reference Figure 9The battery module 2 includes battery cells 58, heat insulation pads 59, buffer cotton 60, Mylar sheets 61, insulating sheets 62, cable ties 63, and aluminum end plates 64. In this embodiment, the battery pack is formed from the outside to the inside by stacking steel strips, aluminum end plates 64, Mylar sheets 61, buffer cotton 60, 12 battery cells 58, and heat insulation pads 59 between the battery cells 58. Twelve battery cells 58 are arranged in series. Heat insulation pads 59 are placed between the cells 58 for insulation and heat protection. Buffer cotton 60 is placed at both ends of the series-connected cells 58 to buffer thermal expansion. Mylar sheets 61 are placed outside the buffer cotton 60 to prevent leakage from the cells 58. Insulating sheets 62 are placed on top of the cells 58 to prevent leakage between battery modules 2. Cable ties 63 are fitted around the twelve cells 58 to prevent them from loosening and rubbing against each other. Aluminum end plates 64 are placed between the cable ties 63 and the Mylar sheets 61 to protect the cells 58 from expansion and deformation. Furthermore, the CCS integrated wiring harness, series aluminum busbars, and insulating sheets 62 at the top of the module enable electrical connections between the cells 58, voltage and temperature sampling of the cells 58, and insulation of the upper part of the module. Each component of the module can withstand the pressure generated by the expansion of the battery cell 58, and can also ensure that the module maintains the stability of its shape and size under various operating conditions.

[0046] The implementation principle of a safe battery pack in this application embodiment is as follows: When the battery pack is charging and discharging normally, the heat collection layer channel 47 of the liquid cooling plate 44 absorbs the heat generated by the battery cell 58, and the coolant flows in the cooling channel, transferring the heat to the heat transfer layer channel 48 for discharge; at the same time, the exhaust fan 6 is driven to rotate by the external motor 43, blowing air onto the battery module 2. The cold air passes through the cooling channel 46 and exchanges heat with the cooling channel to form cold air, which is blown onto the battery module 2 to achieve cooling. This dual suppression of heat accumulation reduces the probability of fire from the source.

[0047] If a fire breaks out inside the battery pack, the temperature inside the outer casing 1 rises rapidly. The first airbag 13 of the first safety structure 7 and the second airbag 52 of the second safety structure 8 expand synchronously due to the high temperature. The expansion of the first airbag 13 pushes the squeezing claw 14 to rotate. The squeezing claw 14 pushes the squeezing rod 16 to squeeze the fire extinguishing airbag 9 out of the protective casing 11. At the same time, the connecting structure 17 drives the clamping claw 15 to clamp the fire extinguishing airbag 9. The expansion of the second airbag 52 squeezes the fire extinguishing ball 51, pushes the elastic membrane 54 to bulge out and be punctured by the barbs 55. The fire extinguishing ball 51 falls out and drives the exhaust fan 6 to rotate, achieving cooling without power supply.

[0048] The support rod 22 near the ignition point bends when heated, and the support tube 10 tilts towards the ignition point, aligning the fire extinguishing airbag 9 with the ignition point. At the same time, as the clamping claw 15 clamps the fire extinguishing airbag 9, the second connecting plate 19 pushes the push plate 33 to retract the collar 31, and the spike 29 punctures the fire extinguishing airbag 9, releasing carbon dioxide fire extinguishing gas to reduce the oxygen content around the ignition point and extinguish the fire. The fire extinguishing ball 51 rolls along the rolling channel 50 towards the ignition point. After the shell 57 is heated and melted, the dry ice core 56 is exposed. The dry ice core 56 releases carbon dioxide to assist the first safety structure 7 in extinguishing the fire, while absorbing a large amount of heat to cool down and inhibit the spread of the ignition point.

[0049] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A safety battery pack, characterized in that, It includes a housing (1), a battery module (2) installed inside the housing (1), a liquid cooling structure (3) located at the bottom of the battery module (2) for cooling the battery module (2), and a fire extinguishing mechanism (5) for extinguishing fire when the battery module (2) catches fire. The fire extinguishing mechanism (5) includes an exhaust fan (6) that blows air on one side of the battery module (2), a first safety structure (7) set at the ignition points at both ends of the battery module (2) for fire extinguishing, and a second safety structure (8) used in conjunction with the exhaust fan (6) and assisting the first safety structure (7) in fire extinguishing. The exhaust fan (6) works in conjunction with the liquid cooling structure (3) to cool down the battery module (2). The first safety structure (7) includes a fire extinguishing airbag (9), which releases fire extinguishing gas after the fire starts to reduce the oxygen content at the ignition point. The second safety structure (8) includes a fire extinguishing ball (51), which drives the exhaust fan (6) to rotate and roll towards the ignition point after the fire starts to release the fire extinguishing gas inside.

2. A safety battery pack according to claim 1, characterized in that, The first safety structure (7) further includes a support tube (10) rotatably disposed inside the outer shell (1), a protective shell (11) disposed on the support tube (10) and used to store the fire extinguishing airbag (9), a first airbag (13) fixed to the bottom of the protective shell (11) and expanded by heat, a squeezing claw (14) rotatably mounted on the protective shell (11) and rotating in conjunction with the expansion of the first airbag (13), and a squeezing rod (16) cooperating with the squeezing claw (14) to squeeze the fire extinguishing airbag (9) out of the protective shell (11); The top of the protective shell (11) is provided with a through hole (12) for the fire extinguishing airbag (9) to be extruded. The extrusion rod (16) is rotatably installed inside the protective shell (11). One side of the extrusion rod (16) abuts against the extrusion claw (14), and the other side abuts against the fire extinguishing airbag (9) to drive the fire extinguishing airbag (9) to have a tendency to extrude towards the through hole (12).

3. A safety battery pack according to claim 2, characterized in that, The support tube (10) is provided with a support structure (20) that supports the support tube (10) and drives the support tube (10) to tilt toward the fire point when heated. The support structure (20) includes a snap ring (21) sleeved on the support tube (10), a support rod (22) snapped into the snap ring (21) and easily deformed and bent by heat, and a snap structure (23) for fixing the support rod (22) in the snap ring (21). The snap structure (23) includes a snap ball (24) for fixing the support rod (22) and a first spring (25) for pressing the snap ball (24) against the support rod (22). The snap ball (24) is provided with a snap groove (27) to prevent the snap ball (24) from falling off. The support tube (10) tilts toward the ignition point when the support rod (22) is heated and bent.

4. A safety battery pack according to claim 2, characterized in that, The first safety structure (7) also includes a clamping claw (15) for clamping the fire extinguishing airbag (9) that has been squeezed out of the protective shell (11), and a connecting structure (17) is provided between the squeezing claw (14) and the clamping claw (15). The connection structure (17) includes a first connecting plate (18) and a second connecting plate (19) rotatably connected to the extrusion claw (14). The second connecting plate (19) connects the first connecting plate (18) and the clamping claw (15) to drive the clamping claw (15) to rotate when the extrusion claw (14) rotates.

5. A safety battery pack according to claim 4, characterized in that, The clamping claw (15) is provided with a release structure (28) for releasing fire extinguishing gas. The release structure (28) includes a spike (29) that extends and retracts within the clamping claw (15) near one end of the fire extinguishing airbag (9) and is used to puncture the fire extinguishing airbag (9) after it is squeezed out of the protective shell (11); a second spring (30) that is slidably installed within the clamping claw (15) and has the tendency to push the spike (29) out of the clamping claw (15); a collar (31) that is sleeved outside the spike (29) and prevents the spike (29) from extending out of the clamping claw (15); a third spring (32) that has the tendency to extend the collar (31) and lock the spike (29); and a push plate (33) that is slidably installed within the clamping claw (15) and is controlled by the second connecting plate (19) to push the collar (31) back.

6. A safety battery pack according to claim 1, characterized in that, The exhaust fan (6) includes a shaft (37) fixedly installed on the inner wall of the outer casing (1), a rotating ring (38) rotatably installed on the shaft (37), a connecting seat (39) slidably installed on the rotating ring (38), and fan blades (40) fixed on the connecting seat (39) and distributed in a circumferential array. The rotating ring (38) has a connecting groove (41) for a matching connecting seat (39), and the fan blade (40) has a receiving arc-shaped channel (42) for receiving and guiding the fire extinguishing ball (51).

7. A safety battery pack according to claim 6, characterized in that, The liquid cooling structure (3) includes a liquid cooling plate (44) containing coolant. The liquid cooling plate (44) includes a serpentine LCP cooling channel (45) disposed at the bottom of the battery module (2) and a cooling channel (46) vertically disposed in the LCP cooling channel (45) for supplying cool air to the exhaust fan (6). The cooling channel (46) is located between the exhaust fan (6) and the battery module (2). The LCP cooling channel (45) includes a heat collection layer channel (47) for conducting heat from the battery cell (58) and allowing coolant to flow, and a heat transfer layer channel (48) for discharging heat from the coolant.

8. A safety battery pack according to claim 6, characterized in that, The second safety structure (8) includes a rolling chamber (49) located at the top of the housing (1) for storing the fire extinguishing ball (51). The rolling chamber (49) has an opening (53) for the fire extinguishing ball (51) to roll onto the fan blade (40). The rolling chamber (49) is provided with a second airbag (52) that expands when heated to compress the fire extinguishing ball (51). An elastic membrane (54) is provided on the opening (53) to prevent the fire extinguishing ball (51) from falling. A barb (55) is provided on the opening (53) for puncturing the elastic membrane (54). When the second airbag (52) is heated, it squeezes the fire extinguishing ball (51) until the elastic membrane (54) bulges downward and is punctured by the barbs (55). The fire extinguishing ball (51) falls out from the opening (53) onto the fan blades (40) of the exhaust fan (6) to drive the exhaust fan (6) to start.

9. A safety battery pack according to claim 8, characterized in that, The second safety structure (8) also includes a rolling channel (50) for the fire extinguishing ball (51) to roll after falling. The rolling channel (50) points towards the first safety structure (7). There are two exhaust fans (6). The rolling channels (50) are respectively inclined on both sides of the outer shell (1) and allow the fire extinguishing ball (51) to roll to both sides after falling. The fire extinguishing ball (51) includes a dry ice core (56) and a shell (57) that has been heated and melted. As the fire extinguishing ball (51) rolls toward the ignition point in the rolling channel (50), the shell (57) is heated and melted to expose the dry ice core (56) for further heat dissipation.

10. A safety battery pack according to claim 1, characterized in that, The battery module (2) includes battery cells (58) arranged in series, a heat insulation pad (59) disposed between the battery cells (58) for insulation and heat insulation, a buffer cotton (60) disposed at both ends of the battery cells (58) for buffering the thermal expansion of the battery cells (58), a Mylar sheet (61) disposed outside the buffer cotton (60) for preventing leakage of the battery cells (58), an insulating sheet (62) disposed on the top of the battery cells (58) for preventing leakage between the battery modules (2), a cable tie (63) sleeved on the outside of the battery cells (58) for preventing the battery cells (58) from loosening, and an aluminum end plate (64) disposed between the cable tie (63) and the Mylar sheet (61) for protecting the battery cells (58) from deformation.

Images