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CN-120690990-B - Lithium battery pack thermal management system and control method

CN120690990BCN 120690990 BCN120690990 BCN 120690990BCN-120690990-B

Abstract

The invention relates to the technical field of battery thermal management, in particular to a lithium battery pack thermal management system and a control method. The cooling air pipe is fixedly connected to a battery box, a bottom protection plate is arranged in the battery box, a cooling channel is arranged in the cooling plate, the cooling channel is provided with a first converging part, a second converging part and a third converging part, the cooling plate is provided with a lithium battery, an upper cover plate is fixedly connected to the battery box, and an electric control ball valve is arranged on the cooling plate. According to the invention, the first converging part, the second converging part and the third converging part are arranged to control the flow direction of the cooling liquid, so that the cooling liquid is controlled to enter the area which is preferentially cooled after entering the battery box, the cooling liquid is preferentially contacted with the area with higher temperature, the cooling liquid carries heat in the area with higher temperature to continuously flow, and the temperature of each place in the battery box is reduced, so that the influence of uneven temperature distribution on the operation of the lithium battery pack is reduced.

Inventors

  • WU LIJUN
  • LI YAHUI
  • CHEN YA
  • LIU NAN

Assignees

  • 江苏智泰新能源科技有限公司

Dates

Publication Date
20260512
Application Date
20250627

Claims (8)

  1. 1. The utility model provides a lithium battery pack thermal management system, includes cooling tuber pipe (101) that rigid coupling is on battery case (1) and communicates with its inside to and install in bottom backplate (2) of battery case (1) downside, cooling tuber pipe (101) external outside air feed system, install cooling plate (3) in battery case (1), be provided with the cooling channel in cooling plate (3), characterized by, the cooling channel is provided with first converging portion (301), second converging portion (302) and third converging portion (303), the upside of cooling plate (3) is provided with a plurality of lithium cell (4) that are located in battery case (1), the upside rigid coupling of battery case (1) has upper cover plate (5); An electric control ball valve (6) is jointly installed on the cooling plate (3) and the upper cover plate (5), the electric control ball valve (6) is communicated with a liquid inlet pipeline (601), the liquid inlet pipeline (601) is communicated with an external cooling circulation system, and the electric control ball valve (6) is used for supplying cooling liquid to one of the first converging part (301), the second converging part (302) and the third converging part (303) so as to control the flowing direction of the cooling liquid in a cooling channel of the cooling plate (3); The cooling plate (3) is fixedly connected with three first pipelines (7), the three first pipelines (7) are respectively communicated with the first converging part (301), the second converging part (302) and the third converging part (303), and the first pipelines (7) are provided with temperature sensors (701); All first pipeline (7) are connected with rotating plate (8) in a common rotation mode, the valve rod of automatically controlled ball valve (6) with rotating plate (8) rigid coupling is so that rotating plate (8) rotates, rotating plate (8) is provided with three circulation hole (801), circulation hole (801) be used for with first converging portion (301) second converging portion (302) with one intercommunication in third converging portion (303), battery box (1) rigid coupling have with rotating plate (8) rotate second pipeline (9) of being connected, second pipeline (9) are provided with three intercommunication mouthful, circulation hole (801) be used for with one of them intercommunication mouth on second pipeline (9), second pipeline (9) and external cooling circulation system intercommunication.
  2. 2. A lithium battery pack thermal management system according to claim 1, characterized in that the upper side of the cooling plate (3) is provided with the same number of ventilation slots (304) as the lithium batteries (4), the ventilation slots (304) being located below adjacent lithium batteries (4).
  3. 3. A lithium battery pack thermal management system according to claim 2, characterized in that the first pipe (7) and the second pipe (9) are each provided with a shielding part (10), the number of shielding parts (10) on the first pipe (7) is one, the number of shielding parts (10) on the second pipe (9) is three, and the shielding parts (10) are used for shielding the flow holes (801).
  4. 4. A lithium battery pack thermal management system according to claim 3, characterized in that a plurality of groups of branch channels (11) are arranged in the cooling plate (3) in a straight line, the branch channels (11) are communicated with the cooling channels in the cooling plate (3), and the number of the branch channels (11) in each group is a plurality.
  5. 5. A lithium battery pack thermal management system according to claim 4, characterized in that sliding plates (12) which are linearly distributed and have the same number as the number of the branch channels (11) are slidably connected in the cooling plate (3), the sliding plates (12) are used for plugging a plurality of the branch channels (11) of the same adjacent group, the sliding plates (12) are provided with holes, the holes of the sliding plates (12) are used for communicating a plurality of the branch channels (11) of the same adjacent group, the triggering blocks (13) which are the same in number as the branch channels (11) are slidably connected in the cooling plate (3), the triggering blocks (13) are fixedly connected with the adjacent sliding plates (12), sliding blocks (14) which are the same in number as the triggering blocks (13) are slidably connected in the cooling plate (3), the triggering blocks (13) are used for extruding and moving adjacent the sliding blocks (14), the sliding blocks (14) are used for being inserted into the cooling channels of the cooling plate (3) so as to adjust the areas between the cooling blocks (3) and the cooling blocks (14) which are fixedly connected with the elastic flow surfaces (15).
  6. 6. A lithium battery pack thermal management system according to claim 5, wherein a trigger frame (16) is connected between the battery box (1), the cooling plate (3) and the upper cover plate (5) in a sealing sliding manner, the sliding plate (12) is fixedly connected with the trigger frame (16), and an elastic piece is fixedly connected between the trigger frame (16) and the adjacent battery box (1).
  7. 7. A lithium battery pack thermal management system according to claim 6, characterized in that the width of the trigger block (13) is smaller than the diameter of the cooling channel on the cooling plate (3) so that the movable distance of the slide block (14) is smaller than the diameter of the cooling channel on the cooling plate (3).
  8. 8. A control method of a lithium battery pack thermal management system, using the lithium battery pack thermal management system of claim 7, comprising the following specific steps: The method comprises the steps that 1, an external cooling circulation system and an electric control ball valve (6) are opened, the external cooling circulation system supplies cooling liquid to a liquid inlet pipeline (601), the cooling liquid enters one of a first converging part (301), a second converging part (302) and a third converging part (303) by controlling the electric control ball valve (6) to rotate, then the cooling liquid enters a cooling channel of a cooling plate (3), and the cooling liquid flows into a region with higher temperature preferentially; In the process of rotating the electric control ball valve (6), a valve rod of the electric control ball valve (6) drives the rotating plate (8) to rotate, so that one first pipeline (7) is plugged, the other two first pipelines (7) are respectively aligned with the adjacent circulating holes (801), and then cooling liquid in the cooling plate (3) flows back to an external cooling circulation system through the first pipelines (7), the circulating holes (801) and the second pipelines (9), so that the circulation cooling of the cooling liquid is realized; After the temperature distribution of each part in the battery box (1) is uniform, an external air supply system is started, air flow generated by the external air supply system blows a trigger frame (16) to move, the trigger frame (16) triggers a sliding block (14) to move through a trigger block (13), an elastic block (15) is compressed, the sliding block (14) is inserted into a cooling channel of a cooling plate (3), the flow area of the cooling channel on the cooling plate (3) is reduced, one part of cooling liquid flows along the cooling channel of the cooling plate (3), and the other part of cooling liquid flows into a branch channel (11), so that the flowing range of the cooling liquid in circulation is increased; Step 4, after the temperature distribution of each part in the battery box (1) is uneven, closing an external air supply system, and rebounding an elastic block (15) and driving a sliding block (14) to reset, so that the sliding block (14) is not inserted into a cooling channel of a cooling plate (3) any more, and the flowing range of cooling liquid is greatly reduced when the cooling liquid circulates; And 5, when the use is stopped, closing the external air supply system, the external cooling circulation system and the electric control ball valve (6).

Description

Lithium battery pack thermal management system and control method Technical Field The invention relates to the technical field of battery thermal management, in particular to a lithium battery pack thermal management system and a control method. Background Along with the rapid development of electric vehicles and energy storage equipment, lithium battery packs are widely applied due to high energy density and long cycle life, however, a great amount of heat can be generated by internal resistance and chemical reaction in the working process of lithium batteries, if the heat cannot be timely dissipated, the problems of overheating inside the battery packs, performance attenuation, even thermal runaway and the like can be caused, therefore, an efficient and accurate heat management system is crucial to guaranteeing the safety and stability of the lithium battery packs, and the heat management of the lithium battery packs at present mainly depends on cooling modes such as air cooling, liquid cooling, phase change materials and the like, wherein the liquid cooling system is widely adopted due to high heat dissipation efficiency. However, the cooling plate used in the traditional liquid cooling system is designed with a fixed flow channel, the flow direction of the cooling liquid is single, the temperature of each position on the lithium battery pack is unevenly distributed due to the difference of heat dissipation conditions, if the position where the cooling liquid enters is far away from the position where the cooling liquid enters on the lithium battery pack in a higher temperature area, the cooling liquid cannot be directly cooled down aiming at the local high temperature area of the lithium battery pack after entering the cooling plate, and the cooling liquid can be influenced by the temperature of other areas in the flowing process, so that the cooling effect of the cooling liquid is reduced after the cooling liquid reaches the area where the temperature on the lithium battery pack is unevenly distributed, thereby leading to heat dissipation lag of the high temperature area and aggravating the uneven temperature distribution state of each position of the lithium battery. Disclosure of Invention In order to overcome the disadvantages noted in the background art, the present invention provides a lithium battery pack thermal management system and a control method. The technical scheme includes that the lithium battery pack thermal management system comprises a cooling air pipe fixedly connected to a battery box and communicated with the inside of the battery box, and a bottom guard plate arranged at the lower side of the battery box, wherein the cooling air pipe is externally connected with an external air supply system, a cooling plate is arranged in the battery box, a cooling channel is arranged in the cooling plate, the cooling channel is provided with a first converging part, a second converging part and a third converging part, a plurality of lithium batteries positioned in the battery box are arranged at the upper side of the cooling plate, and an upper cover plate is fixedly connected at the upper side of the battery box; the cooling plate with the automatically controlled ball valve is installed jointly to the upper cover plate, automatically controlled ball valve intercommunication has the feed liquor pipeline, feed liquor pipeline and external cooling circulation system intercommunication, automatically controlled ball valve is used for with the coolant liquid supply to first converging portion the second converging portion with one of them of third converging portion, in order to control the coolant liquid in the direction of cooling channel internal circulation of cooling plate. More preferably, the cooling plate is provided with ventilation grooves having the same number as the lithium batteries on the upper side, and the ventilation grooves are located below the adjacent lithium batteries. More preferably, the cooling plate is fixedly connected with three first pipelines, the three first pipelines are respectively communicated with the first converging portion, the second converging portion and the third converging portion, and the first pipelines are provided with temperature sensors. More preferably, all the first pipelines are connected with a rotating plate in a rotating mode, the valve rod of the electric control ball valve is fixedly connected with the rotating plate so that the rotating plate rotates, the rotating plate is provided with three flow holes, the flow holes are used for being communicated with one of the first converging portion, the second converging portion and the third converging portion, the battery box is fixedly connected with a second pipeline which is rotationally connected with the rotating plate, the second pipeline is provided with three communication ports, the flow holes are used for being communicated with one of the communication ports on the second pipeline,