Battery pack with external water cooling interface and control strategy

Abstract

The invention relates to the field of new energy batteries, in particular to a battery pack with an external water-cooling interface and a control strategy, the battery pack comprises a battery box body and a box cover, the box cover is detachably mounted at the upper end of the battery box body, the battery box body is a hollow box body with the periphery closed and the upper end open, and the box cover is detachably mounted at the lower end of the battery box body. A liquid cooling plate is integrally arranged on a bottom plate of the battery box body, a water pipe interface is arranged on the liquid cooling plate, and the water pipe interface is positioned outside the battery box body, so that the problem that the interface of the liquid cooling plate is positioned inside the battery pack after most of liquid cooling battery pack boxes are subjected to liquid cooling at the present stage is solved; and if leakage occurs at an interface, insulation of the whole bag is caused, and potential safety hazards are generated.

Description

Technical Field

[0001] The present invention relates to the field of new energy batteries, and particularly to a battery pack with an external water-cooling interface and a control strategy. Background Art

[0002] With the popularization of new energy vehicles, the trend of electrification is intensifying. As the most important component of electric vehicles, the battery pack has a great impact on the performance of the battery under high and low temperature conditions. At present, most battery packs use liquid cooling and heating thermal management methods to heat and cool the battery pack. Currently, for most liquid-cooled battery packs, the interfaces of the liquid-cooled plates after integration are inside the battery pack. If there is a leak at the interface, it will cause insulation problems for the entire pack and pose safety hazards.

[0003] At the present stage, a battery pack with an external water-cooling interface and a control strategy are proposed to solve the problems raised in the above background art. Summary of the Invention

[0004] The purpose of the present invention is to provide a battery pack with an external water-cooling interface and a control strategy to solve the problem that for most current liquid-cooled battery packs, the interfaces of the liquid-cooled plates after integration are inside the battery pack. If there is a leak at the interface, it will cause insulation for the entire pack and pose safety hazards.

[0005] A battery pack with an external water-cooling interface includes a battery box body and a box cover. The box cover is detachably installed at the upper end of the battery box body. The battery box body is a hollow box body that is closed on all sides and open at the upper end. A liquid-cooled plate is integrally provided on the bottom plate of the battery box body. A water pipe interface is provided on the liquid-cooled plate. The water pipe interface is located outside the battery box body and is connected to the liquid-cooled plate.

[0006] Further defined, a left anti-collision beam and a right anti-collision beam are provided inside the battery box body. Battery cells are arranged between the left anti-collision beam and the right anti-collision beam. The battery cells are arranged between the left anti-collision beam and the right anti-collision beam in a CTP layout.

[0007] Further defined, it further includes a connector. The connector is installed on the side wall of the battery box body. The socket part of the connector is located outside the side wall of the battery box body and is connected to the whole vehicle, and the connection part is located inside the side wall of the battery box body and is connected to the busbar.

[0008] Further defined, the busbar is located between the left anti-collision beam and the left side wall of the battery box body. The busbar is arranged in sections. The busbar is connected to the connection part of the connector through a connecting wing, and the busbar is connected to the battery cells.

[0009] Further defined, anti-collision beams are provided on both the front and rear sides of the battery box body.

[0010] Further defined, it includes slow charge heating and fast charge heating. The slow charge heating is as follows: when the starting battery minimum temperature is less than or equal to 0°C, pure heating is carried out. At this time, the requested voltage is the real-time voltage + 10V, and the WPTC current is 20A; when heated to the minimum temperature ≥ 12°C, charging starts. The requested voltage is the full charge voltage, and the current is 3 times the charging demand current + the VCU requested load terminal current. When the temperature during charging drops to 8°C, it enters the process of charging while heating again. It is not allowed to work below -35°C. When charging starts with the starting battery minimum temperature above 0°C, when the temperature during charging drops to -4°C, it enters the heating process again;

[0011] The fast charge heating is as follows: when the starting battery minimum temperature T1' is below -4°C, charging is not allowed, and only a heating request is sent to the VCU; when heated to the battery minimum temperature T1' ≥ -4°C and lasts for 30S, it enters the process of charging while heating. When heated to the minimum temperature T1' > 25°C, the heating request to the VCU is closed, and charging starts. When the temperature during charging drops to 8°C, it enters the process of charging while heating again. When the starting battery minimum temperature T1' is between -4°C and 25°C, it enters the process of charging while heating. When heated to the minimum temperature T1' > 25°C, it enters pure charging. When the temperature during charging drops to 8°C, it enters the process of charging while heating again. When T1' < -35°C, the battery is not allowed to work. When the starting battery minimum temperature is above 25°C, direct charging starts. When the temperature during charging drops to 8°C, it enters the process of charging while heating.

[0012] Further defined, the working conditions of pure heating and charging while heating in the fast charge heating are as follows: when in pure heating, the requested voltage = full charge voltage; when charging while heating, the requested voltage = full charge voltage, and the requested current = the charging MAP table current.

[0013] The beneficial effects of the present invention compared with the current stage technology are as follows:

[0014] The anti-collision beams provided on both the front and rear sides of the battery box body can avoid damage to the battery pack caused by strong impacts.

[0015] A water pipe interface is provided outside the battery box body. The water pipe interface is connected to the liquid cooling plate. In case of problems such as leakage in the liquid cooling system, the external water pipe interface can prevent the coolant from directly contacting the precision electronic components and battery cells inside the battery pack, reducing the risk of safety accidents such as battery short circuits caused by coolant leakage. At the same time, the external interface is easier to be discovered and processed when problems occur, and measures can be taken in time to prevent the failure from further expanding, ensuring the safe operation of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional structural schematic diagram of the present invention;

[0017] Figure 2 This is a three-dimensional schematic diagram of the internal structure of the present invention.

[0018] The labels in the figure respectively correspond to: 1 - battery box body, 2 - box cover, 3 - liquid cooling plate, 4 - water pipe interface, 5 - left anti-collision swelling beam, 6 - right anti-collision swelling beam, 7 - battery cell, 8 - connector, 9 - bus bar, 10 - anti-collision beam. Detailed implementation manners

[0019] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments. Embodiment

[0020] As Figure 1 and Figure 2 shown, a battery pack assembly with an external water-cooling interface includes a battery box body 1 and a box cover 2. The box cover 2 is detachably installed on the upper end of the battery box body 1. The battery box body 1 is a hollow box body that is closed on all sides and open at the upper end. The battery box body is made of aluminum profiles and is welded together by friction stir welding. A liquid cooling plate 3 is integrally provided on the bottom plate of the battery box body 1. A water pipe interface 4 is provided on the liquid cooling plate 3. The water pipe interface 4 is located outside the battery box body 1 and is connected to the liquid cooling plate 3. A left anti-collision swelling beam 5 and a right anti-collision swelling beam 6 are provided inside the battery box body 1. A battery cell 7 is provided between the left anti-collision swelling beam 5 and the right anti-collision swelling beam 6. The battery cell 7 is arranged between the left anti-collision swelling beam 5 and the right anti-collision swelling beam 6 in a CTP layout manner. The left anti-collision swelling beam 5 and the right anti-collision swelling beam 6 play a role in preventing the battery cell from swelling. A connector 8 is provided on the side wall of the battery box body 1. The socket part of the connector 8 is located outside the side wall of the battery box body 1 and is connected to the whole vehicle, and the connection part is located inside the side wall of the battery box body 1 and is connected to the bus bar 9. The bus bar 9 is located between the left anti-collision swelling beam 5 and the left side wall of the battery box body 1. The bus bar 9 is arranged in sections and is connected to the connection part of the connector 8 through a connecting wing. The bus bar 9 is connected to the battery cell 7. Current is transmitted to the whole vehicle through the bus bar 9 and the connector 8. Anti-collision beams 10 are provided on both the front and rear sides of the battery box body 1, which can reduce the damage to the battery pack caused by severe impact in an accident.

[0021] When problems such as leakage occur in the liquid cooling system, the water pipe interface 4 being set outside the battery box body 1 can prevent the coolant from directly contacting the precision electronic components and battery cells inside the battery pack, reducing the risk of safety accidents such as battery short circuits caused by coolant leakage. At the same time, the external water pipe interface 4 is easier to detect and handle when there is a problem, and measures can be taken in a timely manner to prevent the failure from further expanding, ensuring the safe operation of the battery pack.

[0022] A control strategy applicable to a battery pack with an external water-cooling interface, including slow charging heating and fast charging heating. Slow charging heating: When the starting minimum battery temperature is less than or equal to 0°C, pure heating is carried out. At this time, the requested voltage is the real-time voltage + 10V, and the WPTC current is 20A. When the heating reaches the minimum temperature ≥ 12°C, charging starts. The requested voltage is the full charge voltage, and the current is 3 times the charging demand current + the VCU requested load terminal current. When the temperature during charging drops to 8°C, it enters the process of charging while heating again. It is not allowed to work below -35°C. When the starting minimum battery temperature is above 0°C, charging starts. When the temperature during charging drops to -4°C, it enters the heating process again. Fast charging heating: When the starting minimum battery temperature T1' is below -4°C, charging is not allowed, and only a heating request is sent to the VCU. When the heating reaches the minimum battery temperature T1' ≥ -4°C and lasts for 30S, it enters the process of charging while heating. When the heating reaches the minimum temperature T1' > 25°C, the heating request to the VCU is closed, and charging starts. When the temperature during charging drops to 8°C, it enters the process of charging while heating again. When the starting minimum battery temperature T1' is between -4°C and 25°C, it enters the process of charging while heating. When the heating reaches the minimum temperature T1' > 25°C, it enters pure charging. When the temperature during charging drops to 8°C, it enters the process of charging while heating again. When T1' < -35°C, the battery is not allowed to work. When the starting minimum battery temperature is above 25°C, direct charging starts. When the temperature during charging drops to 8°C, it enters the process of charging while heating. The working conditions of pure heating and charging while heating in fast charging heating are as follows: When pure heating, the requested voltage = the full charge voltage. When charging while heating, the requested voltage = the full charge voltage, and the requested current = the charging MAP table current.

[0023] The above has introduced in detail a battery pack with an external water-cooling interface and its control strategy provided by the present invention. The description of specific embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the premise of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A battery pack with an external water cooling interface, comprising a battery box body (1) and a box cover, wherein the box cover (2) is detachably mounted on the upper end of the battery box body (1), and the battery box body (1) is a hollow box body with closed sides and an open upper end, characterized in that: A liquid cooling plate (3) is integrated on the bottom plate of the battery box body (1), a water pipe interface (4) is provided on the liquid cooling plate (3), the water pipe interface (4) is located outside the battery box body (1), and the water pipe interface (4) is connected to the liquid cooling plate (3).

2. A battery pack with an external water cooling interface according to claim 1, characterized in that: The battery box body (1) is provided with a left anti-collision expansion beam (5) and a right anti-collision expansion beam (6) inside, and a battery cell (7) is provided between the left anti-collision expansion beam (5) and the right anti-collision expansion beam (6). The battery cell (7) is arranged between the left anti-collision expansion beam (5) and the right anti-collision expansion beam (6) in a CTP arrangement manner.

3. A battery pack with an external water cooling interface according to claim 1, characterized in that: It also includes a connector (8), which is mounted on the side wall of the battery box body (1), the socket portion of the connector (8) is located outside the side wall of the battery box body (1) and connected to the entire vehicle, and the connection portion is located inside the side wall of the battery box body (1) and connected to the bus (9).

4. A battery pack with an external water cooling interface according to claim 3, characterized in that: The busbar (9) is located between the left anti-collision expansion beam (5) and the left side wall of the battery box body (1), the busbar (9) is arranged in sections, the busbar (9) is connected to the connecting part of the connector (8) through the connecting wing, and the busbar (9) is connected to the battery cell (7).

5. The battery pack with an external water cooling interface according to claim 1, characterized in that Anti-collision beams (10) are provided on both the front and rear sides of the battery box body (1).

6. A control strategy for a battery pack with an external water cooling interface according to any one of claims 1 to 5, characterized in that: It includes slow charging heating and fast charging heating. The slow charging heating is as follows: the starting battery minimum temperature is less than or equal to 0℃ for pure heating. At this time, the requested voltage is the real-time voltage + 10V, and the WPTC current is 20A; when the minimum temperature is heated to ≥12℃, charging begins, the requested voltage is the full-charge voltage, and the current is 3 charging demand current + VCU requested load-end current. When the charging process temperature drops to 8℃, the charging and heating process begins again. It is not allowed to work below -35℃. The starting battery minimum temperature is above 0℃ for charging, and the heating process begins again when the charging process temperature drops to -4℃. The fast charging heating is as follows: when the initial battery minimum temperature T1' is below -4℃, charging is not allowed, and only heating is requested from the VCU; when the battery minimum temperature T1' is heated to ≥-4℃ and lasts for 30S, the charging and heating process begins; when the minimum temperature T1' is heated to 25℃, the heating request is turned off to the VCU, and charging begins; when the charging process temperature drops to 8℃, the charging and heating process begins again; when the initial battery minimum temperature T1' is between -4℃ and 25℃, the charging and heating process begins; when the minimum temperature T1' is heated to 25℃, pure charging begins; when the charging process temperature drops to 8℃, the charging and heating process begins again; when T1' is <-35℃, the battery is not allowed to work; when the initial battery minimum temperature is above 25℃, direct charging is performed; when the charging process temperature drops to 8℃, the charging and heating process begins.

7. The control strategy for a battery pack with an external water cooling interface according to claim 6, characterized in that: The operating conditions of pure heating and heating while charging in the fast charging heating are as follows: when pure heating, the requested voltage = full charge voltage, when charging and heating, the requested voltage = full charge voltage, and the requested current = charging MAP table current.

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