Quick charging battery module with heat management function

Abstract

The invention belongs to the technical field of electric vehicles, and provides a quick charging battery module with a heat management function. The fast-charging battery module comprises a first battery cell, a first condensation glue layer, a first heat conduction plate, an aerogel heat insulation layer, a second heat conduction plate, a second condensation glue layer and a second battery cell which are sequentially stacked in the thickness direction, through a'condensation gel-heat conduction plate-aerogel 'composite sandwich structure, rapid temperature equalization of the surface of the battery cell is realized through high-heat-conduction condensation gel, a longitudinal heat conduction channel is established by the heat conduction plate, a heat barrier layer is formed by combining ultralow-heat-conduction aerogel, and meanwhile, the contradictory requirements of rapid charging heat dissipation and thermal runaway protection are met.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to a fast-charging battery module with a thermal management function. Background Art

[0002] With the surge in demand for fast charging in electric vehicles and portable electronic devices, the thermal management problem of high-energy-density lithium-ion batteries under fast-charging conditions has become increasingly prominent. During the fast-charging process, the polarization reaction inside the battery intensifies, generating a large amount of Joule heat and reaction heat in a short period of time, causing the battery cell temperature to rise sharply. Studies have shown that when the surface temperature of the battery cell exceeds 60°C, the decomposition rate of the electrolyte will increase exponentially, causing safety hazards such as SEI film rupture and lithium dendrite growth, which seriously restricts the practical application of fast-charging technology.

[0003] Traditional thermal management solutions mostly adopt a unidirectional heat dissipation design. For example, the liquid-cooled plate-bonded heat dissipation structure disclosed in Chinese patent CN112436229A can achieve local heat extraction, but there are problems such as a single heat dissipation path and uneven temperature field distribution. Especially in multi-layer battery cell stacking modules, the thermal coupling effect between adjacent battery cells is significant. If there is a lack of effective thermal isolation measures, it is very easy to cause a thermal runaway chain reaction. Although the phase change materials used in the prior art (such as Chinese patent application CN113937435A) can alleviate the temperature rise through latent heat absorption, their thermal conductivity is generally lower than 3W / (m·K), resulting in insufficient lateral heat diffusion capacity, and the phase change temperature range is poorly matched with the fast charging condition. In addition, conventional thermal insulation materials (such as polyurethane foam) are prone to thermal degradation in high temperature environments, making it difficult to meet the requirements of long-term cyclic use.

[0004] In response to the above problems, some improvement schemes attempt to set the heat conduction and insulation functions in layers. For example, JP2020155824A proposes to alternately set graphite sheets and ceramic fiber layers between battery cells, but the actual heat dissipation efficiency of this structure is limited due to the high interface contact thermal resistance. At the same time, the thermal conductivity of its insulation layer is only at the level of 0.05W / (m·K), which cannot effectively block the heat conduction from the high temperature zone to the adjacent battery cells. More importantly, the existing technology has not yet solved the problem of synchronous management of heating on both sides of the battery cell during fast charging, resulting in a temperature gradient of more than 15°C in the thickness direction of the module, which seriously affects the consistency of the battery. Therefore, it is urgent to develop a composite thermal management architecture with bidirectional high-efficiency heat conduction and super insulation characteristics, which can block the heat transfer path between the module layers while realizing rapid heat dissipation on both sides of the battery cell, and establish a real-time temperature feedback mechanism to meet the thermal safety and cycle life requirements in high-rate fast charging scenarios. Summary of the invention

[0005] In view of this, the present invention provides a fast charging battery module with thermal management function, which aims to solve the contradiction between fast charging and thermal runaway protection existing in the existing fast charging technology.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The present invention provides a fast-charging battery module with a thermal management function, comprising: The first battery cell; a first cold gel layer, a first surface of which is in contact with the first battery cell and is used to quickly absorb heat generated during the charging and discharging process of the first battery cell; a first heat conducting plate, a first surface of which is in contact with the second surface of the first cold gel layer, and is used to diffuse heat evenly along a planar direction; The aerogel heat insulation layer has a first surface that is bonded to the second surface of the first heat conducting plate, and is used to block heat conduction between the battery cells on both sides and delay the spread of heat when the battery cell on one side is in thermal runaway; A second heat conducting plate, a first surface of which is in contact with the second surface of the aerogel heat insulating layer, and is used to diffuse heat evenly along a planar direction; a second cold gel layer, a first surface of which is in contact with the second surface of the second heat conducting plate, and is used to quickly absorb heat generated during the charging and discharging process of the second battery cell; a second battery cell, attached to the second surface of the second cold gel layer; Wherein, the thermal conductivity of the aerogel insulation layer is ≤0.03W / (m·K); The thermal conductivity of the first heat conducting plate and the second heat conducting plate are both ≥10000 W / (m·K).

[0007] Furthermore, the first heat conducting plate layer and the second heat conducting plate layer are made of aluminum alloy, copper or graphene composite material.

[0008] Furthermore, the thickness of the first heat conducting plate layer and the second heat conducting plate layer are both 1.3-3 mm.

[0009] Furthermore, the thickness of the aerogel insulation layer is 0.5-4 mm; the porosity of the aerogel insulation layer is ≥90%.

[0010] Furthermore, the stacked structure is arranged in a centrally symmetrical manner, and the aerogel insulation layer is located at the geometric center of the module.

[0011] Furthermore, the contact area coverage of the first cold gel layer and the second cold gel layer with the corresponding battery core is ≥95%.

[0012] Furthermore, the first battery cell and the second battery cell are both lithium-ion battery cells.

[0013] It can be seen from the above technical solution that compared with the prior art, the beneficial effects of the present invention are as follows: The present invention adopts a composite sandwich structure of "cold gel-thermal conductive plate-aerogel" to achieve rapid temperature uniformity on the surface of the battery cell through the high thermal conductivity of cold gel, establish a longitudinal heat conduction channel with the thermal conductive plate, and form a thermal barrier layer with the ultra-low thermal conductivity aerogel, thereby solving the conflicting needs of fast charging heat dissipation and thermal runaway protection.

[0014] The symmetrical stacking design of the present invention enables the thermal management component to serve dual cells simultaneously, significantly improving space utilization while ensuring thermal runaway protection capabilities.

[0015] The present invention arranges the aerogel insulation layer at the geometric center of the module to form a bidirectional insulation barrier when thermal runaway occurs, and cooperates with the longitudinal heat diffusion of the heat conducting plate to increase the temperature rise delay time of adjacent battery cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A front view of a fast-charging battery module provided in Example 1 of the present invention, wherein from left to right are a first battery cell, a first cold gel layer, a first heat conducting plate, an aerogel insulation layer, a second heat conducting plate, a second cold gel layer, and a second battery cell; Figure 2 A front view of a fast-charging battery module provided in Example 2 of the present invention, wherein from left to right are a first battery cell, a first cold gel layer, a first heat conducting plate, an aerogel insulation layer, a second heat conducting plate, a second cold gel layer, and a second battery cell; Figure 3 This is a physical picture of the fast-charging battery module provided by the present invention, wherein 1 is a first battery cell, 2 is a first cold gel layer, 3 is a first heat conducting plate, 4 is an aerogel insulation layer, 5 is a second heat conducting plate, 6 is a second cold gel layer, and 7 is a second battery cell. DETAILED DESCRIPTION

[0017] The present invention provides a fast-charging battery module with a thermal management function, comprising: The first battery cell; a first cold gel layer, a first surface of which is in contact with the first battery cell and is used to quickly absorb heat generated during the charging and discharging process of the first battery cell; a first heat conducting plate, a first surface of which is in contact with the second surface of the first cold gel layer, and is used to diffuse heat evenly along a planar direction; The aerogel heat insulation layer has a first surface that is bonded to the second surface of the first heat conducting plate, and is used to block heat conduction between the battery cells on both sides and delay the spread of heat when the battery cell on one side is in thermal runaway; A second heat conducting plate, a first surface of which is in contact with the second surface of the aerogel heat insulating layer, and is used to diffuse heat evenly along a planar direction; a second cold gel layer, a first surface of which is in contact with the second surface of the second heat conducting plate, and is used to quickly absorb heat generated during the charging and discharging process of the second battery cell; a second battery cell, attached to the second surface of the second cold gel layer; Wherein, the thermal conductivity of the aerogel insulation layer is ≤0.03W / (m·K); The thermal conductivity of the first heat conducting plate and the second heat conducting plate are both ≥10000 W / (m·K).

[0018] In the present invention, the materials of the first heat conducting plate layer and the second heat conducting plate layer are both aluminum alloy, copper or graphene composite material.

[0019] In the present invention, the thickness of the first heat conducting plate layer and the second heat conducting plate layer are both 1.3-3 mm, preferably 1.5-2.5 mm, and more preferably 2 mm.

[0020] In the present invention, the thickness of the aerogel insulation layer is 0.5-4 mm, preferably 1.0-3.0 mm, and more preferably 2.0 mm; the porosity of the aerogel insulation layer is ≥90%.

[0021] In the present invention, the stacked structure is arranged in a centrally symmetrical manner, and the aerogel insulation layer is located at the geometric center of the module.

[0022] In the present invention, the contact area coverage of the first cold gel layer and the second cold gel layer with the corresponding battery core is ≥95%.

[0023] In the present invention, liquid cooling pipes are embedded in the first heat conducting plate and the second heat conducting plate, and the liquid cooling pipes are connected to an external cooling system.

[0024] In the present invention, if the temperature is too low in winter, the battery may not be able to provide sufficient starting current under extremely low temperature, resulting in the vehicle being unable to start normally. The heat conductive plate can transmit the temperature of the external cooling system to the battery module, so that the battery reaches a suitable temperature and maintains normal operation of the vehicle.

[0025] In the present invention, both the first battery cell and the second battery cell are lithium-ion battery cells.

[0026] In the present invention, the first battery core, the second battery core, the first cold gel layer, the second cold gel layer and the aerogel insulation layer have the same length, and the length of the first heat conducting plate and the second heat conducting plate are both greater than the length of the aerogel insulation layer.

[0027] In the present invention, the cryogels used in the first cryogels layer and the second cryogels layer are both structural cryogels, and the structural cryogels include aluminum-plastic film, cryogels, glass fiber mesh and aluminum-plastic film in order from top to bottom.

[0028] In the present invention, the thickness of the aluminum-plastic film is 0.08-0.12 mm, preferably 0.1 mm.

[0029] In the present invention, the thickness of the glass fiber mesh is 0.75 times that of the structural cryogel.

[0030] In the present invention, the mesh size of the glass fiber mesh is preferably 12×14 mm.

[0031] In the present invention, the thickness of the cryogel is 0.4-5 mm, preferably 0.5 mm.

[0032] In the present invention, the cold gel used is from Chinese Patent Publication No. CN117126430B or Chinese Patent Publication No. CN117363238B.

[0033] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0034] Example 1 The present embodiment discloses a fast-charging battery module with a thermal management function, including: a first battery cell, a first cold gel layer, a first heat conducting plate (copper-based composite material), an aerogel insulation layer, a second heat conducting plate (copper-based composite material), a second cold gel layer, and a second battery cell, which are stacked in sequence along the thickness direction.

[0035] Wherein, both ends of the first heat conducting plate and the second heat conducting plate extend out of the fast charging battery module respectively, so as to be connected to an external cooling system.

[0036] Example 2 The present embodiment discloses a fast-charging battery module with a thermal management function, including: a first battery cell, a first cold gel layer, a first heat conducting plate (copper-based composite material), an aerogel insulation layer, a second heat conducting plate (copper-based composite material), a second cold gel layer, and a second battery cell, which are stacked in sequence along the thickness direction.

[0037] One end of the first heat conducting plate and the second heat conducting plate extends out of the fast charging battery module for connecting to an external cooling system.

[0038] The fast-charging battery module prepared in Example 1 was subjected to a performance test. The test method, basis and results are shown in Table 1.

[0039] Table 1 Performance test results of fast charging battery module

[0040] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A fast-charging battery module with thermal management function, characterized in that: Including stacked in sequence along the thickness direction: The first battery cell; a first cold gel layer, a first surface of which is in contact with the first battery cell and is used to quickly absorb heat generated during the charging and discharging process of the first battery cell; a first heat conducting plate, a first surface of which is in contact with the second surface of the first cold gel layer, and is used to diffuse heat evenly along a planar direction; The aerogel heat insulation layer has a first surface that is bonded to the second surface of the first heat conducting plate, and is used to block heat conduction between the battery cells on both sides and delay the spread of heat when the battery cell on one side is in thermal runaway; A second heat conducting plate, a first surface of which is in contact with the second surface of the aerogel heat insulating layer, and is used to diffuse heat evenly along a planar direction; a second cold gel layer, a first surface of which is in contact with the second surface of the second heat conducting plate, and is used to quickly absorb heat generated during the charging and discharging process of the second battery cell; a second battery cell, attached to the second surface of the second cold gel layer; Wherein, the thermal conductivity of the aerogel insulation layer is ≤0.03W / (m·K); The thermal conductivity of the first heat conducting plate and the second heat conducting plate are both ≥10000 W / (m·K).

2. The fast-charging battery module with thermal management function according to claim 1, characterized in that: The materials of the first heat conducting plate layer and the second heat conducting plate layer are both aluminum alloy, copper-based composite material or graphene composite material.

3. The fast-charging battery module with thermal management function according to claim 2, characterized in that: The thickness of the first heat conducting plate layer and the second heat conducting plate layer are both 1.3-3 mm.

4. The fast-charging battery module with thermal management function according to claim 2, characterized in that: The thickness of the aerogel thermal insulation layer is 0.5-4 mm; the porosity of the aerogel thermal insulation layer is ≥90%.

5. The fast-charging battery module with thermal management function according to claim 4, characterized in that: The stacked structure is arranged in a centrally symmetrical manner, and the aerogel insulation layer is located at the geometric center of the module.

6. The fast-charging battery module with thermal management function according to claim 5, characterized in that: The contact area coverage of the first cold gel layer and the second cold gel layer with the corresponding battery core is ≥95%.

7. The fast-charging battery module with thermal management function according to any one of claims 1 to 6, characterized in that: The first battery cell and the second battery cell are both lithium-ion battery cells.

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