CN210403966U

CN210403966U - Novel battery pack thermal management system based on square battery

Info

Publication number: CN210403966U
Application number: CN201920986469.5U
Authority: CN
Inventors: 刘自强; 黄菊花; 曹铭; 鄢琦昊; 胡金
Original assignee: Nanchang University
Current assignee: Nanchang University
Priority date: 2019-06-26
Filing date: 2019-06-26
Publication date: 2020-04-24
Anticipated expiration: 2029-06-26

Abstract

The utility model discloses a novel group battery thermal management system based on prismatic cell contains the cooling water set of battery group module, water pump, water tank and the adjustable temperature of water passageway metal cavity, prismatic cell and the laminating in turn of composite phase change material. The water channel metal cavity is formed by bonding a cavity upper cover and a cavity base, and the cavity upper cover and the cavity base are both connected with a baffle plate. The composite phase-change material is formed by mixing and hot-pressing paraffin and expanded graphite in a molten state. The two ends of the metal cavity are respectively provided with a cooling water inlet and a high-temperature water outlet, and cooling water is provided by a water pump, a water tank and a water chilling unit with adjustable water temperature and is connected into a circulation loop. The utility model discloses utilize phase change material and liquid cooling coupling heat management principle, when battery low strength operation, can not open the liquid cooling circulation, only utilize composite phase change material heat absorption can. When the battery is in high-intensity operation, the liquid cooling cycle is started.

Description

Novel battery pack thermal management system based on square battery

Technical Field

The invention belongs to the technical field of power battery thermal management devices, and particularly relates to a novel battery pack thermal management system based on a square battery.

Background

With the increasing demand of human beings on power batteries, battery technology gradually develops towards high specific energy and high power. The prismatic battery pack generates a large amount of heat during rapid charge and discharge or continuous high-strength operation, and the temperature of the battery body is rapidly increased due to the generation of the heat.

However, when the battery works, a 'comfortable' temperature range exists, the aging of the battery is accelerated due to overhigh temperature, the service life of the battery is greatly reduced, and thermal runaway can be caused in serious cases, so that the battery is burnt or explodes. Therefore, it is necessary to provide thermal management to the battery.

Common battery thermal management techniques include air cooling, liquid cooling, and phase change material cooling. The air cooling heat dissipation efficiency is low, and the structure is simple; the liquid cooling has strong heat dissipation capacity, but the heat dissipation is not uniform, and the simple and efficient liquid cooling system has a more complex structure; the phase-change material has light weight and good heat dissipation effect, but the absorbed heat is difficult to dissipate, and the phase-change material loses the temperature control capability once being melted. Therefore, a battery heat dissipation system with good temperature control effect and high heat dissipation efficiency is needed.

Disclosure of Invention

Aiming at the defects and problems in the prior art, the invention aims to provide a novel battery pack thermal management system based on square batteries.

The invention is realized by the following technical scheme:

the utility model provides a novel group battery thermal management system based on square battery, contains battery pack module, water pump, water tank and the cooling water set of adjustable temperature that water passageway metal cavity, square battery and compound phase change material laminated in turn.

Wherein the water channel metal cavity is formed by gluing an upper cavity cover and a cavity base. The cavity upper cover is special in shape, the surface of the cavity upper cover is inwards sunken to form a cuboid space region, and the region is used for placing the battery pack module. The cavity base both ends are equipped with water passage entry and export, have formed water passage between the two after cavity upper cover is connected with the cavity base. All there is the baffling board on cavity upper cover and the cavity base, and cooling water gets into in the people cavity and the baffling board of upper cover and base through the water passage entry to take away the heat that the group battery conduction was come more effectively.

The battery pack module is formed by alternately attaching a plurality of single square batteries and composite phase-change material blocks, and the formed battery pack module is placed in a metal cavity with an inward concave shape. The composite phase-change material is uniformly mixed with paraffin wax in a molten state through expanded graphite, and is hot-pressed to form a rectangular block under the combined action of a tablet press and a die. The selected paraffin is fully refined paraffin, the melting temperature is lower than 50 ℃, the paraffin can absorb a large amount of battery heat and keep the temperature constant when being melted, the expanded graphite can enhance the heat conductivity of the phase-change material, the paraffin can be prevented from leaking in the melting state, and the service life of the composite phase-change material is prolonged.

The water pump, the water tank and the water chilling unit capable of adjusting water temperature are connected with the water channel inlet and the water channel outlet of the metal cavity through pipelines to form a water cooling circulation loop. The water pump, the water tank and the water-temperature-adjustable water chilling unit provide circulating low-temperature cooling water, the water tank is used for storing water, the water pump promotes water circulation, and the water chilling unit can cool high-temperature water flowing out of the metal cavity.

The working principle of the invention is as follows:

the battery heat management system adopts a composite phase change material and liquid cooling coupling heat management technology, the battery pack generates a large amount of heat when charging and discharging and high-strength work are carried out, most of the heat is absorbed by the phase change material, and when the phase change material reaches the phase change temperature, the phase change latent heat can be utilized to absorb a large amount of heat and keep the temperature constant. Once the paraffin in the composite phase-change material is completely melted, the latent heat of phase change does not work any more, although the expanded graphite can prevent the leakage of the paraffin, the temperature of the battery inevitably rises sharply, and the temperature is conducted to the upper cover of the metal cavity with the shape of the battery pack module sunken inwards. At the moment, cooling water from the water chilling unit enters the water channel of the metal cavity, the cooling water and the metal thin wall of the upper cover of the metal cavity fully exchange heat through the baffle plate, and flowing cooling water takes away heat conducted from the battery and the composite phase change material, so that the temperature of the battery pack is controlled in a reasonable interval in a liquid cooling coupling mode through the composite phase change material.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention

FIG. 2 is a combination view of a battery pack and a metal cavity according to the present invention

FIG. 3 is a view showing the structure of the metal cavity base of the present invention

FIG. 4 is a structural view of the upper cover of the metal cavity of the present invention

FIG. 5 is a structural view of a battery module according to the present invention

FIG. 6 is a schematic view showing the direction of water flow at the bottom of the metal cavity according to the present invention

FIG. 7 is a schematic view of the water flow direction at the side of the metal cavity of the present invention

Detailed Description

The invention will be further described with reference to the accompanying drawings.

As shown in fig. 1 and 2, a novel battery pack thermal management system based on a square battery comprises a water channel metal cavity upper cover 1, a metal cavity base 3, a battery pack module 2 with the square battery and a composite phase change material alternately attached, a water pump 6, a water tank 5 and a water chilling unit 4 with adjustable water temperature.

The metal cavity upper cover 1 comprises a baffle plate 102, a metal cavity upper cover thin-wall shell 103 and a cuboid concave space 101. The metal cavity base 3 comprises a baffle plate 301, a water channel inlet 302 and

water channel outlets

303 and 304, and the metal cavity base is a thin-wall shell. The battery module 2 includes a battery 201, a composite phase change material block 202. The water pump 6 promotes the circulation of system water, the water tank 5 is used for storing cooling water, and the water chilling unit 4 can cool high-temperature water into low-temperature water at a set temperature.

Wherein, each part realizes through water pipe and adapter that the water circulation return circuit is connected in the system, and metal cavity upper cover 1 is connected through inseparable bonding with metal cavity base 3, can make battery 201 all can derive the heat fast except five faces of upper surface like this, and the quantity of compound phase change material 202 thickness and battery 201 all can be adjusted according to actual conditions. And the composite phase-change material block 202 is formed by melting, uniformly mixing and hot-pressing expanded graphite and paraffin, the paraffin serving as a phase-change material base material can absorb a large amount of heat, and the expanded graphite serving as a phase-change support material can prevent the paraffin from leaking after melting and can keep the shape of the composite phase-change material.

The working process of the invention is as follows:

the battery pack generates a large amount of heat during high-intensity operation and rapid charge and discharge, wherein the heat on the two front surfaces of the battery 201 is absorbed by the composite phase-change material blocks 202 which are alternately attached to the surface of the battery, and the heat on the two side surfaces and the bottom of the battery passes through the thin wall 103 of the upper cover of the metal cavity to be absorbed and taken away by flowing cooling liquid. The composite phase-change material can absorb heat in a large amount by using phase-change latent heat and keep constant temperature before paraffin serving as a component of the composite phase-change material is not completely melted, however, once the phase-change material is completely melted, the heat absorption effect of the phase-change latent heat is lost, the temperature of a battery is rapidly increased, heat in the phase-change material can be led out and taken away by introducing liquid cooling, and the phase-change material is guaranteed not to break through the melting temperature.

When the battery runs at low strength, the liquid cooling circulation can be not started, and only the composite phase change material is used for absorbing heat. When the battery is in high-intensity operation, the liquid cooling cycle is started. Cooling water circulates under the action of a water pump, low-temperature cooling water from an outlet of the water chilling unit 4 is introduced into an inlet 302 of a water channel of the metal cavity, and after entering a water channel formed by the upper cover 1 of the metal cavity and the base 3 of the metal cavity, the cooling water is fully subjected to heat exchange with the thin wall 103 of the upper cover of the metal cavity through the action of the

baffle plates

102 and 301, so that heat conducted from the battery 201 and the composite phase change material 202 is taken away, and fig. 6 and 7 are schematic diagrams of water flow directions under the action of the baffle plates respectively, so that the temperature of the battery pack 2 is controlled within a reasonable range. The working process well combines the advantages of phase change materials and liquid cooling heat management, so that each battery in the battery pack has five surfaces to quickly realize heat dissipation.

The foregoing merely represents preferred embodiments of the invention, which are described in some detail and detail, and therefore should not be construed as limiting the scope of the invention. It should be noted that, for those skilled in the art, various changes, modifications and substitutions can be made without departing from the spirit of the present invention, and these are all within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a novel group battery thermal management system based on square battery which characterized in that: the water cooling system comprises a water channel metal cavity, a battery pack module, a water pump, a water tank and a water chilling unit, wherein the battery pack module is formed by alternately attaching a square battery and a composite phase-change material; the battery pack module is formed by alternately combining composite phase-change material blocks and single batteries, and the combined battery pack is placed in a metal cavity with a special shape; the two ends of the metal cavity are respectively provided with a cooling water inlet and a high-temperature water outlet, cooling water is provided by a water pump, a water tank and a water chilling unit with adjustable water temperature and is connected into a circulation loop, and the composite phase-change material is formed by mixing and hot-pressing paraffin and expanded graphite in a molten state.

2. The novel prismatic cell based battery pack thermal management system of claim 1, wherein: the metal cavity is composed of a cavity upper cover and a cavity base and forms a water channel cavity area, water channel inlets and water channel outlets are formed in two ends of the cavity base, and the shape of the metal cavity is inwards sunken and forms a cuboid space area.

3. The novel prismatic cell based battery pack thermal management system of claim 1, wherein: the baffle plates are respectively connected to the cavity upper cover and the cavity base, and cooling water enters the cavity from the water channel inlet and flows through the baffle plates of the upper cover and the base so as to more effectively take away heat conducted by the battery pack.

4. The novel prismatic cell based battery pack thermal management system of claim 1, wherein: the battery pack module is formed by alternately attaching single batteries and composite phase change materials, and the combined battery pack module is placed in a concave space region of the metal cavity.

5. The novel prismatic cell based battery pack thermal management system of claim 1, wherein: the composite phase-change material is formed by melting, mixing and hot-pressing paraffin and expanded graphite, and is attached to the surface of the battery to absorb heat generated during the operation, the charge and the discharge of the battery.

6. The novel prismatic cell based battery pack thermal management system of claim 1, wherein: the water tank is used for storing water, and the water pump promotes hydrologic cycle, and the cooling water set can cool off the high temperature water that the metal cavity flows out.