Energy storage subrack and energy storage system

Abstract

The utility model provides an energy storage plug-in box and an energy storage system. The energy storage plug-in box comprises a box body with a sealed cavity, a heat pipe arranged on the box body and insulated cooling liquid filled in the sealed cavity. A supporting reinforcing plate is arranged at the bottom of the box body, a containing cavity is defined between the supporting reinforcing plate and the bottom of the box body, the heat pipe is in a U shape and is provided with a horizontal evaporation section and condensation sections connected to the two ends of the evaporation section, the evaporation section is located in the containing cavity, and the two condensation sections are arranged on the opposite side walls of the box body respectively. And at least part or all of the battery cells accommodated in the sealing cavity are immersed in the cooling liquid. According to the energy storage subrack provided by the utility model, the heat dissipation area can be increased and the contact thermal resistance can be reduced through the arranged cooling liquid, and meanwhile, the heat pipe adopts the U-shaped structure with the condensation sections at the two ends, so that the heat transfer capability is more excellent, the heat in the box body can be timely and effectively guided out by utilizing the high heat conduction characteristic of the heat pipe, and the heat dissipation effect can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage devices, in particular to an energy storage plug box. The utility model also relates to an energy storage system provided with the above energy storage plug box. Background Technique

[0002] The battery energy storage cabinet is composed of a large number of lithium battery packs connected in series and parallel with high energy density. During the charge and discharge process, a large amount of heat will be generated, which will cause the temperature of the battery cells to rise. Temperature is a key factor affecting the energy storage system. Excessive temperature of the battery cells affects the life and performance of the battery cells, and may also cause thermal runaway and trigger safety accidents.

[0003] The safe and efficient long-term operation of the battery energy storage system depends on the temperature consistency of each battery cell during the charge and discharge process. Uneven temperature distribution inside the energy storage system will exacerbate the aging and attenuation of the battery cells, shorten the cycle life of the energy storage system, and even pose potential safety hazards. The battery temperature difference is mainly divided into two types: the temperature difference inside the battery, which is manifested as the temperature uniformity of the battery; the temperature difference between battery monomers, which is manifested as the temperature consistency of the batteries.

[0004] Reasons for the temperature difference inside the battery: In the low-temperature heating or high-temperature heat dissipation condition of the water-cooling system, when the battery plug box is heated or cooled on one side, due to the large thermal resistance of the battery plug box itself, a large temperature difference will occur inside. Reasons for the temperature difference between battery monomers: mainly due to the unreasonable layout of the battery module and the thermal management structure.

[0005] At present, the commonly used heat dissipation methods for battery energy storage systems are natural heat dissipation, forced air cooling, and liquid cooling.

[0006] Among them, the efficiency of natural heat dissipation is relatively low, and the space inside the container is narrow, and the air circulation is not convenient, so it is difficult to meet the temperature control requirements; the liquid cooling technology mainly uses liquid cooling plates at the bottom or on the side for heat dissipation, which occupies a large space inside the plug box and has a high cost, and there is a risk of liquid leakage. In order to reduce costs, water-cooling plates are usually arranged on the large surface side of the battery cells, which will make the temperature of the contact surface between the battery cells and the water-cooling plates lower, while the opposite side cannot dissipate heat directly because it needs to conduct heat to this side for heat dissipation, so the temperature will be higher than that of the contact surface with the cold plate, which is not conducive to the temperature consistency of the battery cells themselves. In order to make the heat transfer between the battery cells and the cold plate better, thermal conductive glue is usually applied in the middle. If the application is uneven, the contact thermal resistance between the battery cells and the cold plate will be inconsistent, which will lead to inconsistent heat transfer from each battery cell to the cold plate, thus the temperature consistency of each battery cell inside the plug box cannot be guaranteed; when using liquid cooling for heat dissipation, additional liquid cooling pipelines and water machines need to be arranged in the energy storage system, which increases the cost of the energy storage system and occupies a large amount of space, and there is a great risk of liquid leakage at the joints and connectors of the liquid cooling pipelines during a large number of plugging and unplugging operations, posing potential safety hazards.

[0007] Forced air cooling uses industrial air conditioners and fans for refrigeration. Although it can meet the heat dissipation requirements of the energy storage system and the cost is within an acceptable range, the air conditioner unit occupies and consumes a large amount of space and additional electrical energy, making this heat dissipation solution have certain limitations. Since cold air needs to be blown into the battery cassette, air ducts are provided on the cassette body, making the internal environment communicate with the external environment, which easily allows external water vapor and dust to enter the battery cassette, posing a certain degree of safety hazard. Summary of the Invention

[0008] In view of this, the present utility model aims to propose an energy storage cassette to improve the heat dissipation effect and ensure the temperature consistency of each battery cell inside the cassette and the temperature consistency inside each battery cell.

[0009] To achieve the above object, the technical solution of the present utility model is realized as follows:

[0010] An energy storage cassette includes a box body having a sealed cavity, a heat pipe provided on the box body, and an insulating coolant filled in the sealed cavity;

[0011] A support reinforcement plate is provided at the bottom of the box body. A receiving cavity is defined between the support reinforcement plate and the bottom of the box body. The heat pipe is in a U shape and has a horizontal evaporation section and condensation sections connected to both ends of the evaporation section. The evaporation section is located in the receiving cavity, and the two condensation sections are respectively provided on opposite side walls of the box body. At least part or all of the battery cells accommodated in the sealed cavity are immersed in the coolant.

[0012] Further, the condensation section is integrated on the side wall of the box body.

[0013] Further, the evaporation section is fixed in the receiving cavity by a thermally conductive structural adhesive.

[0014] Further, heat dissipation fins are provided on the side of the side wall of the box body facing the outside of the sealed cavity.

[0015] Further, a plurality of heat pipes are arranged side by side along the length direction or width direction of the box body.

[0016] Further, the heat pipe is a copper-made normal temperature heat pipe, and / or the working medium inside the heat pipe is R134a.

[0017] Further, the coolant is a fluorinated liquid or dimethyl silicone oil.

[0018] Compared with the prior art, the present utility model has the following advantages:

[0019] For the energy storage plug-in box of the present utility model, through the heat pipes arranged on the box body and the coolant filled in the sealed cavity, part or all of the battery cells are immersed in the coolant. In this way, the coolant is in direct contact with the battery cells, which can increase the heat dissipation area, reduce the contact thermal resistance, and transfer the heat of each battery cell to the coolant, facilitating ensuring the temperature consistency of each battery cell in the plug-in box and the temperature consistency inside the battery cells. At the same time, the heat pipe adopts a U-shaped structure with two end condensation sections, which is more excellent in heat transfer ability. Therefore, by utilizing the high thermal conductivity characteristics of the heat pipe, the heat inside the box body can be effectively exported in a timely manner, thereby further improving the heat dissipation effect and ensuring the temperature consistency of each battery cell and the temperature inside each battery cell.

[0020] In addition, integrating the condensation section on the side wall of the box body can not only reduce the thickness of the side wall of the box body, reduce the thermal resistance, facilitate heat dissipation, but also help reduce the weight of the box body and improve the space utilization rate. The evaporation section is fixed in the accommodating cavity by using a thermally conductive structural adhesive, which can not only ensure good thermal conductivity but also ensure the structural strength of the support reinforcing plate to a certain extent.

[0021] In addition, the heat dissipation fins arranged on the outer side of the side wall of the box body cooperate with the heat pipes integrated on the box body, which can facilitate the heat inside the plug-in box to be exported to the outside of the plug-in box and prevent the entry of external water vapor and dust. Multiple heat pipes are provided, which can further improve the heat dissipation effect of the battery cells. The heat pipes adopt copper-based normal-temperature heat pipes, and the working medium adopts R134a, which can ensure good heat transfer at the working temperature of the battery cells. The coolant adopts a fluorinated liquid or dimethyl silicone oil, which has excellent electrical insulation performance, thermal conductivity, thermal stability and chemical stability.

[0022] Another object of the present utility model is to propose an energy storage system, in which the above-mentioned energy storage plug-in box is provided.

[0023] The energy storage system of the present utility model and the energy storage plug-in box as described above have the same beneficial effects as the prior art, and will not be elaborated here. Description of the Drawings

[0024] The drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0025] Figure 1 It is a partial structural schematic diagram of the energy storage plug-in box according to the embodiment of the present utility model;

[0026] Figure 2 It is a perspective view of the energy storage plug-in box according to the embodiment of the present utility model;

[0027] Figure 3Schematic structural diagram of the heat pipe according to the embodiment of the present utility model;

[0028] Figure 4 Schematic structural diagram of the assembly state of the evaporation section and the box body according to the embodiment of the present utility model;

[0029] Explanation of reference numerals:

[0030] 1. Box body; 101. Support and reinforcement plate; 1011. Accommodation cavity;

[0031] 2. Heat pipe; 201. Evaporation section; 202. Condensation section; 20. Thermal conductive structural adhesive;

[0032] 3. Cooling liquid; 4. Battery cell; 10. Energy storage plug box. Specific implementation manners

[0033] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other.

[0034] In the description of the present utility model, it should be noted that if terms indicating orientation or positional relationship such as "upper", "lower", "inner", "outer", etc. appear, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, if terms such as "first", "second", etc. appear, they are also only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0035] In addition, in the description of the present utility model, unless otherwise clearly defined, the terms "installation", "connection", "connection", "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood in combination with the specific situations.

[0036] The present utility model will be described in detail below with reference to the drawings and in combination with the embodiments.

[0037] This embodiment relates to an energy storage plug box, which can improve the heat dissipation effect and ensure the temperature consistency of each battery cell 4 in the plug box and the temperature consistency inside each battery cell 4.

[0038] In terms of the overall structure, the energy storage plug box 10 of this embodiment, as Figure 1 and Figure 2As shown in the figure, it mainly includes a box body 1 with a sealed cavity, a heat pipe 2 provided on the box body 1, and an insulating coolant 3 filled in the sealed cavity. Among them, a support reinforcement plate 101 is provided at the bottom of the box body 1. A receiving cavity 1011 is defined between the support reinforcement plate 101 and the bottom of the box body 1. The heat pipe 2 is in a U shape and has a horizontal evaporation section 201 and condensation sections 202 connected to both ends of the evaporation section 201. The evaporation section 201 is located in the receiving cavity 1011, and part of the two condensation sections 202 is provided on the side wall of the box body 1. The battery cells 4 accommodated in the sealed cavity are at least partially or completely immersed in the coolant 3.

[0039] In this structure, the coolant 3 filled in the sealed cavity is in direct contact with the battery cells 4, and by using the heat conduction between the coolant 3 and the battery cells 4, the contact thermal resistance between the battery cells 4 and the heat conducting element can be reduced. Moreover, part or all of the battery cells 4 in the plug-in box enter the coolant 3, which can increase the heat dissipation area, enabling the heat of each battery cell 4 to be transferred to the coolant 3, facilitating ensuring the temperature consistency of each battery cell 4 in the plug-in box and the temperature consistency inside the battery cells 4. At the same time, the heat pipe 2 adopts a U-shaped structure with two end condensation sections 202, and the high heat conduction characteristic of the heat pipe 2 can be utilized to timely and effectively export the heat inside the box body 1, thereby further improving the heat dissipation effect and ensuring the temperature consistency of each battery cell 4 and the temperature inside the battery cells 4.

[0040] See Figures 1 to 3 As shown in the figure, in this embodiment, the energy storage plug-in box 10 mainly includes a box body 1 with a sealed cavity. The box body 1 is provided with battery cells 4 and electrical components connected to the battery cells 4, etc. As an improvement of this embodiment, a heat pipe 2 is provided on the box body 1 of this embodiment, and an insulating coolant 3 is filled in the sealed cavity.

[0041] Among them, see Figure 2 and Figure 3 As shown in the figure, the heat pipe 2 in this embodiment is in a U shape and has a horizontal evaporation section 201 and condensation sections 202 connected to both ends of the evaporation section 201. At least part or all of the battery cells 4 in the box body 1 are immersed in the coolant 3.

[0042] To better support the battery cells 4 and facilitate the installation of the heat pipe 2, a support reinforcement plate 101 is provided at the bottom of the box body 1 in this embodiment. The cross-section of the support reinforcement plate 101 is in an inverted U shape, and a receiving cavity 1011 is defined between the support reinforcement plate 101 and the bottom of the box body 1. The evaporation section 201 of the heat pipe 2 is located in the receiving cavity 1011, and the two end condensation sections 202 are respectively provided on the opposite side walls of the box body 1.

[0043] As a preferred implementation of this embodiment, in this embodiment, the condensation section 202 on the heat pipe 2 is integrated on the side wall of the box body 1. In the specific implementation, the existing process can be used to form the heat pipe 2 on the side wall of the box body 1, wherein the outer wall of the heat pipe 2 has a fixed part fixedly connected to the side wall of the box body 1, and an internal part and an external part connected to the fixed part, the internal part is located in the accommodating cavity 1011, and the external part is located outside the accommodating cavity 1011. In addition, the length of the condensation section 202 can be designed accordingly according to actual needs. By integrating the condensation section 202 on the side wall of the box body 1, it is not only possible to reduce the thickness of the side wall of the box body 1, reduce thermal resistance, and facilitate heat dissipation, but also help reduce the weight of the box body 1, and also help improve space utilization.

[0044] As a preferred implementation of this embodiment, Figure 4 As shown, in this embodiment, the evaporation section 201 of the heat pipe 2 is fixed in the accommodating cavity 1011 by means of a heat conductive structural adhesive 20. Such a configuration can ensure a good heat conduction effect and also ensure the structural strength of the support reinforcing plate 101 to a certain extent.

[0045] Also as a preferred implementation of this embodiment, a heat dissipation fin is provided on the side wall of the box body 1 of this embodiment, that is, on the side of the side wall of the box body 1 facing the outside of the sealed cavity. The arrangement of the heat dissipation fin, in cooperation with the heat pipe 2 integrated on the box body 1, can facilitate the heat inside the plug-in box to be exported to the outside of the plug-in box, and can prevent the entry of external water vapor and dust.

[0046] Furthermore, as a further preferred embodiment, in this embodiment, a plurality of heat pipes 2 are arranged side by side along the length direction or the width direction of the box body 1 , so as to further improve the heat dissipation effect of the battery core 4 .

[0047] The heat pipe 2 of this embodiment is preferably a copper normal temperature heat pipe 2, and the working medium in the heat pipe 2 is preferably R134a. This ensures that the heat transfer of the battery core 4 is better at the working temperature. At the same time, in this embodiment, the coolant 3 is preferably fluorinated liquid or dimethyl silicone oil, so that the excellent electrical insulation performance, thermal conductivity, thermal stability and chemical stability of the fluorinated liquid or dimethyl silicone oil can be used to effectively prevent corrosion of the battery core 4.

[0048] In the energy storage plug-in box 10 of this embodiment, during the charging and discharging process of the battery cell 4, the fluorinated liquid absorbs the heat of the battery cell 4 to increase the temperature of the fluorinated liquid, and at the same time transfers the heat to the evaporation section 201 of the heat pipe 2. The working medium inside the evaporation section 201 absorbs heat and vaporizes, and the gas phase working medium moves to the condensation section 202, and the heat is discharged through the condensation section 202 and the fins outside the box body 1. The temperature of the gas phase working medium decreases, and it is liquefied into a liquid working medium, thereby completing the heat transfer from the inside of the battery cell 4 to the outside of the battery plug-in box.

[0049] In this embodiment, by directly immersing the battery cell 4 in the fluorinated liquid, the contact thermal resistance can be reduced and the heat transfer area can be increased. Moreover, by using the heat pipe 2 for heat transfer, additional heat dissipation power equipment can be reduced, which plays a certain role in optimizing the cost and space of the entire energy storage system. At the same time, by utilizing the high thermal conductivity of the heat pipe 2 and the condensation section 202 of the heat pipe 2 integrated on the box body 1, as well as the fins on the side wall of the box body 1, the heat inside the plug-in box can be conducted to the outside of the plug-in box. Furthermore, the setting of the sealed cavity can also reduce the entry of external water vapor and dust.

[0050] This embodiment also relates to an energy storage system, in which the energy storage plug-in box 10 as described above is provided.

[0051] By adopting the energy storage plug-in box 10 as above, this embodiment enables the energy storage system not to require additional power devices, and has the advantages of low cost, good sealing performance, small space, low maintenance cost, etc., and can further improve the safety ability of the energy storage system.

[0052] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A storage cassette, characterized in that: It includes a box body with a sealed cavity, a heat pipe provided on the box body, and an insulating coolant filled in the sealed cavity; A support reinforcement plate is provided at the bottom of the box body. A receiving cavity is defined between the support reinforcement plate and the bottom of the box body. The heat pipe is U-shaped and has a horizontal evaporation section and condensation sections connected to both ends of the evaporation section. The evaporation section is located in the receiving cavity and is fixed in the receiving cavity by a thermally conductive structural adhesive. The two condensation sections are respectively arranged on opposite side walls of the box body. At least part or all of the battery cells accommodated in the sealed cavity are immersed in the coolant; The condensation section is integrated on the side wall of the box body. The outer wall of the heat pipe has a fixed part fixed to the side wall of the box body, an inner part and an outer part connected to the fixed part. The inner part is located in the receiving cavity and the outer part is located outside the receiving cavity.

2. The storage cassette according to claim 1, characterized in that: Heat dissipation fins are provided on the side of the box body side wall facing the outside of the sealed cavity.

3. The storage cassette according to claim 1, characterized in that: A plurality of the heat pipes are arranged side by side along the length direction or the width direction of the box body.

4. The storage cassette according to claim 1, characterized in that: The heat pipe is a copper-made normal temperature heat pipe, and / or the working medium in the heat pipe is R134a.

5. The storage cassette according to any one of claims 1 to 4, characterized in that: The coolant is a fluorinated liquid or dimethyl silicone oil.

6. A storage system, characterized in that: The energy storage system is provided with the energy storage plug box according to any one of claims 1 to 5.

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