Battery pack with long service life and small system temperature difference

Abstract

The utility model discloses a battery pack with long service life and small system temperature difference, and belongs to the technical field of battery packs. Comprising a box body, the box body is provided with a battery cell bin and an electrical bin which are separated by a partition plate, the battery cell bin is used for injecting insulation cooling oil and placing battery cells, and the electrical bin is used for installing electrical parts; and the liquid cooling plate is mounted at the bottom of the box body and is used for performing heat exchange with the battery cells, and the battery cells which still have temperature differences after heat exchange are soaked in insulating cooling oil so as to realize temperature balance. The battery cells are completely immersed in the insulating cooling oil, and even if temperature difference exists at positions close to the water inlet and the water outlet, temperature equalization can be realized by means of the heat transfer effect of the insulating cooling oil in the whole battery cell area, so that the system temperature difference of the whole battery pack is reduced, the working environment of the battery pack is more stable, and the service life of the battery pack is prolonged. And the service life of the battery pack is finally prolonged.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the battery pack technical field, and specifically relates to a battery pack with long service life and small system temperature difference. BACKGROUND

[0002] When the traditional square shell battery is assembled into a battery pack, it is usually cooled by air cooling or liquid cooling plate due to the limitation of technical conditions. Due to the limitation of these cooling methods, in the use process, in order to control the temperature difference of the system and reduce the heat of the battery, the capacity of the battery pack is usually not made very large. If the capacity of the battery pack is increased, a larger system temperature difference will be caused, and additional heating or heat preservation treatment of the battery at a specific position is needed, or more cooling surfaces are needed to reduce the temperature difference in the system.

[0003] The battery pack with a larger system temperature difference will have a significantly shortened service life of the battery with a higher temperature in the long-term use process, thereby affecting the service life of the entire battery pack. The smaller the system temperature difference of the battery pack is, the longer the cycle life of the battery pack is. Therefore, how to design a battery pack with small system temperature difference and long service life has become an important research direction in the PACK structure design field.

[0004] At present, in the structure design of the battery pack assembled by the square shell battery, the cooling methods of the internal battery mainly include air cooling and liquid cooling, wherein,

[0005] The air cooling method has a lower cost and a lower requirement for the protection level of the battery pack, but it is difficult to achieve a smaller system temperature difference;

[0006] The liquid cooling plate cooling requires the battery pack to reach the IP67 protection level, and the liquid cooling plate has a water inlet and a water outlet. When working in a high-temperature environment, the temperature of the battery near the water inlet will be lower than that of the battery near the water outlet. In a low-temperature environment, the situation is the opposite. In either case, the system temperature difference is large. INVENTION CONTENTS

[0007] The utility model provides a battery pack with long service life and small system temperature difference.

[0008] The utility model can be realized through the following technical schemes:

[0009] A battery pack with long service life and small system temperature difference comprises:

[0010] A box body has a battery compartment and an electrical compartment separated by a partition plate, the battery compartment is used for injecting insulating cooling oil and placing a battery, and the electrical compartment is used for installing electrical components;

[0011] A liquid cooling plate is installed at the bottom of the box and used for heat exchange with the battery cells, and each battery cell still having a temperature difference after heat exchange is soaked in insulating cooling oil to achieve temperature equalization.

[0012] As a further improvement of the utility model, the panel of the box is provided with an opening and used for mounting the electrical components.

[0013] As a further improvement of the utility model, the electrical components are sealingly connected with the opening.

[0014] As a further improvement of the utility model, the panel of the box is further provided with a cooling oil port, through which the insulating cooling oil is injected into the battery cell compartment or extracted from the battery cell compartment.

[0015] As a further improvement of the utility model, the liquid cooling plate has a water inlet and a water outlet, and the liquid cooling plate has a circulating channel, cooling water enters from the water inlet, flows through the circulating channel and then flows out from the water outlet.

[0016] As a further improvement of the utility model, at least one side of the liquid cooling plate extends outward from the bottom of the box and is used for arranging the water inlet and the water outlet.

[0017] As a further improvement of the utility model, the water inlet, the water outlet, the cooling oil port and the electrical components can be concentrated on the same side of the box.

[0018] As a further improvement of the utility model, it further comprises an upper cover covering the box, and the two are fixed through fasteners.

[0019] As a further improvement of the utility model, a sealing ring is arranged between the box and the upper cover.

[0020] Compared with the prior art, the utility model has the following beneficial effects:

[0021] 1. The battery cells are completely immersed in the insulating cooling oil, and even in the case of temperature difference near the water inlet and the water outlet, the temperature equalization can be realized by the heat transfer effect of the insulating cooling oil in the whole battery cell area, so as to reduce the system temperature difference of the whole battery pack, ensure the working environment more stable, and finally prolong the service life of the battery pack.

[0022] 2. The partition plate divides the box into a battery cell compartment and an electrical compartment, can isolate the insulating cooling oil in the battery cell compartment, avoid the insulating cooling oil entering the electrical compartment, and also avoid the problem of insulating cooling oil leakage through the opening of the electrical components.

[0023] 3、The design of the liquid cooling plate enables the cooling water to effectively take away the heat generated by the battery cell, and the uniform distribution of the cooling water is ensured through the design of the circulation channel, which helps to reduce the temperature difference inside the battery pack and improve the thermal management efficiency and stability of the whole battery pack, and such design plays an important role in prolonging the service life of the battery pack and improving the energy efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is the structure schematic diagram of the box body of the utility model;

[0025] Fig. 2 is the structure schematic diagram of the box body after installing the battery cell;

[0026] Fig. 3 is the structure schematic diagram of the battery pack of the utility model.

[0027] In the figure, 100, box body; 110, partition; 120, battery cell compartment; 130, electrical compartment; 140, battery cell; 150, electrical component; 160, liquid cooling plate; 161, water inlet; 162, water outlet; 170, cooling oil port; 180, upper cover; 190, sealing ring. DETAILED DESCRIPTION

[0028] The following is a specific embodiment of the utility model and further describes the technical method of the utility model in combination with the drawings, but the utility model is not limited to these embodiments.

[0029] As shown in Figs. 1-3 The utility model provides a battery pack with long service life and small system temperature difference, which comprises:

[0030] The box body 100 has the battery cell compartment 120 and the electrical compartment 130 which are separated by the partition 110, the battery cell compartment 120 is used for injecting insulating cooling oil and placing the battery cell 140, and the electrical compartment 130 is used for installing the electrical component 150;

[0031] The liquid cooling plate 160 is installed at the bottom of the box body 100 and is used for heat exchange with the battery cell 140, and the battery cells 140 with temperature difference after heat exchange are soaked in the insulating cooling oil to realize temperature balance.

[0032] It should be noted that, at present, in the structure design of the battery pack assembled by the battery cell, the cooling methods for the internal battery cell mainly include air cooling and liquid cooling, wherein,

[0033] The air cooling method has low cost and does not have high requirements on the protection level of the battery pack, but it is difficult to realize small system temperature difference;

[0034] The liquid cooling plate 160 cooling requires the battery pack to achieve IP67 protection level, and the liquid cooling plate 160 has water inlet 161 and water outlet 162, and the temperature of the battery cell near the water inlet 161 is lower than that of the battery cell near the water outlet 162 when working in high temperature environment, and the situation is opposite in low temperature environment, so there is a problem of large system temperature difference in both cases.

[0035] To solve the above problems, the embodiment proposes an innovative design scheme, that is, the battery cell 140 is completely immersed in the insulating cooling oil, and the liquid cooling mode is used for cooling, as follows:

[0036] 1. Electrical stability guarantee

[0037] The insulating cooling oil does not conduct electricity, which can ensure the electrical stability of the battery cell 140 and avoid the risk of short circuit caused by the cooling medium;

[0038] 2. Efficient heat transfer mechanism

[0039] The insulating cooling oil has high specific heat capacity and good thermal conductivity, which can effectively transfer heat with the battery cell 140, and even in the case of temperature difference near the water inlet 161 and the water outlet 162, the insulating cooling oil can also distribute heat evenly in the whole battery cell 140 area, thereby effectively reducing the system temperature difference of the whole battery pack;

[0040] 3. Stable working environment and prolonging service life

[0041] With the heat transfer effect of the insulating cooling oil, the temperature in the whole battery pack can be more uniformly controlled, so that the battery cell works in a more stable environment, which not only improves the energy efficiency of the battery pack, but also significantly prolongs its service life.

[0042] And the partition plate 110 separates the box 100 into the battery cell compartment 120 and the electrical compartment 130, which can isolate the insulating cooling oil in the battery cell compartment 120, avoid the insulating cooling oil entering the electrical compartment 130, avoid the problem of insulating cooling oil leaking through the opening of the electrical component 150, and protect the electrical component 150 from damage, which helps to prolong the service life of the whole battery pack.

[0043] In addition, the partition plate 110 not only effectively isolates the battery cell compartment 120 and the electrical compartment 130 to prevent the insulating cooling oil from entering the electrical part, but also provides additional safety protection in extreme cases. For example, in the event of a collision, the partition plate can prevent liquid from leaking into the electrical element area, avoiding short circuit and other electrical failures.

[0044] Preferably, the faceplate of the box 100 is provided with an opening for mounting the electrical component 150, and the electrical component 150 is sealingly connected with the opening, which has at least the following advantages:

[0045] 1. Waterproof and dustproof

[0046] The sealing design of the electrical component 150 and the opening can effectively prevent external moisture and dust from entering the inside of the battery pack, especially in harsh outdoor environments, which is crucial for maintaining the cleanliness and electrical performance of the inside of the battery pack;

[0047] 2. Meet the protection level requirements

[0048] For battery packs that need to meet certain protection levels (such as IP67), it can help meet such standards and ensure that the battery pack can still work normally after being immersed in water at a certain depth for a certain period of time;

[0049] 3. Simplify maintenance

[0050] Good sealing performance can also help simplify the daily maintenance of the battery pack, reducing troubleshooting and cleaning work caused by the entry of external contaminants.

[0051] Preferably, the faceplate of the box 100 is also provided with a cooling oil port 170, through which the insulating cooling oil is injected into the cell compartment 120 or extracted from the cell compartment 120;

[0052] By setting the cooling oil port 170, the user can conveniently add or replace the insulating cooling oil, which provides great convenience for maintaining the optimal working state of the battery pack. Regularly replacing the cooling oil not only maintains its cooling effect, but also prolongs the service life of the battery pack.

[0053] Preferably, the liquid cooling plate 160 has a water inlet 161 and a water outlet 162, and the liquid cooling plate 160 has a circulating channel (not shown in the figure) inside. The cooling water enters from the water inlet 161, flows through the circulating channel, and then flows out from the water outlet 162;

[0054] The design of the liquid cooling plate 160 allows the cooling water to effectively carry away the heat generated by the cells, and the design of the circulating channel ensures uniform distribution of the cooling water, which helps to reduce the temperature difference inside the battery pack and improve the thermal management efficiency and stability of the entire battery pack. Such design plays an important role in prolonging the service life of the battery pack and improving energy efficiency.

[0055] Preferably, the liquid cooling plate 160 has at least one side extending outward from the bottom of the box 100 and used for setting the water inlet 161 and the water outlet 162, and the water inlet 161, the water outlet 162, the cooling oil port 170 and the electrical component 150 can be concentrated on the same side of the box 100;

[0056] Such a design can facilitate centralized management, and the operator can complete all connection and inspection tasks in a relatively concentrated area, thereby improving work efficiency, and for integration with external systems (such as the cooling system of a vehicle), the centralized design of the interface makes the arrangement and connection of pipelines simpler, and reduces unnecessary bending and complex wiring.

[0057] Preferably, the upper cover 180 is further included, which covers the box 100 and is fixed thereon through fasteners, and such a design not only ensures the stability of the structure, but also facilitates installation and disassembly, and is convenient for subsequent maintenance or repair work.

[0058] Further, the sealing ring 190 is laid between the box 100 and the upper cover 180, which can effectively prevent external moisture and dust from entering the battery pack, improve the waterproof and dustproof performance, help to achieve a higher protection level (such as IP67), and can also prevent the insulation cooling oil in the cell compartment 120 from leaking outward, thereby not only enhancing the protection performance of the battery pack, but also indirectly prolonging the service life. Reducing the influence of the external environment on the battery pack means that the internal components can maintain the best working state for a longer period of time, thereby reducing the overall operating cost.

[0059] The technical means disclosed in the utility model scheme are not limited to the technical means disclosed in the above technical means, and also include technical solutions composed of any combination of the above technical features. The above is the specific implementation manner of the utility model, and it should be pointed out that for ordinary skilled persons in the technical field, some improvements and refinements can be made without departing from the principle of the utility model, and these improvements and refinements are also regarded as the protection range of the utility model.

[0060] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the utility model embodiment are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture (such as shown in the drawings), and if the specific posture changes, the directional indications also change accordingly.

[0061] In addition, the descriptions such as "first", "second", "one" and the like in the present application are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0062] In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixing" and the like should be broadly understood, for example, "fixing" can be fixed connection, or detachable connection, or integrated; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0063] In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist, nor is it within the protection scope required by the present application.

Claims

1. A battery pack having a long life and a small system temperature difference, characterized by, The application relates to a battery box, comprising: a box body having an electric cell compartment and an electric component compartment separated by a partition, the electric cell compartment being used for injecting insulating cooling oil and placing electric cells, and the electric component compartment being used for mounting electric components; a liquid cooling plate mounted at the bottom of the box body and used for heat exchange with the electric cells, each electric cell still having a temperature difference after heat exchange, and the temperature difference being balanced by immersion in insulating cooling oil.

2. The battery pack of claim 1, wherein, A panel of the box body is provided with an opening and used for mounting the electric components.

3. The battery pack of claim 2, wherein, The electric components are in sealed connection with the opening.

4. The battery pack of claim 1, wherein, The panel of the box body is further provided with a cooling oil port, through which insulating cooling oil is injected into the electric cell compartment or extracted from the electric cell compartment.

5. The battery pack of claim 1, wherein, The liquid cooling plate has a water inlet and a water outlet, and the liquid cooling plate has a circulating channel, cooling water enters the water inlet, flows along the circulating channel and then flows out of the water outlet.

6. The battery pack of claim 5, wherein, At least one side of the liquid cooling plate extends outwards from the bottom of the box body and is used for arranging the water inlet and the water outlet.

7. The battery pack of claim 6, wherein, The water inlet, the water outlet, the cooling oil port and the electric components are concentrated on the same side of the box body. 8.The battery pack with long service life and small system temperature difference according to claim 1, characterized in that, The application further comprises an upper cover covering the box body, and the two are fixed through fasteners.

9. The battery pack of claim 8, wherein, A sealing ring is arranged between the box body and the upper cover.

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