CN222365670U - Battery pack shell, liquid cooling battery pack and modularized energy storage system - Google Patents

Abstract

The present application relates to the field of energy storage technology, and in particular to a battery pack housing, a liquid-cooled battery pack, and a modular energy storage system, wherein the battery pack housing includes a base, the base is used to support and fix the battery pack; and an upper cover, the upper cover can be connected to the base in a covering manner, and a receiving cavity with an opening on one side is formed inside the upper cover, and when the upper cover is fixed to the base, the battery pack is located in the receiving cavity; wherein the base is a rectangular frame of aluminum profile structure as a whole; and the upper cover is injection molded in one piece. The advantages of the present application are: it can reduce the overall weight of the energy storage system.

Description

Battery pack shell, liquid cooling battery pack and modularized energy storage system

Technical Field

The application relates to the technical field of energy storage, in particular to a battery pack shell, a liquid cooling battery pack and a modularized energy storage system.

Background

The world demand for energy continues to increase, but because of the unstable nature of renewable energy sources, solar photovoltaic, wind power motors and energy storage systems must be widely installed. The energy storage system is a system for storing energy in the form of electric energy and the like through different media and releasing the energy when the energy is needed.

The energy storage system mainly comprises a battery pack and a current transformer. The battery pack is formed by connecting a plurality of battery cells in series and is used for realizing the storage and release of electric energy as a main carrier, the converter PCS (Power Conversion System, a power conversion system is also called converter) is connected between the battery pack and a power grid (or a load), and is a device for realizing the bidirectional conversion of electric energy, which can not only invert the direct current of the battery pack into alternating current and transmit the alternating current to the power grid or supply the alternating current to the alternating current load for use, but also rectify the alternating current of the power grid into the direct current and charge the battery pack. The converter can accurately control the amplitude, frequency and waveform of the output current in the electric energy conversion process, thereby meeting the specific requirements of a power grid (or load). Therefore, the energy storage converter improves the running performance and efficiency of the whole energy storage system by realizing high-efficiency, safe and controllable conversion of electric energy, and becomes an important ring in the technical field of energy storage.

However, the conventional energy storage system considers the self-power capacity, so that a plurality of battery packs are integrally connected, which results in heavy overall weight of the energy storage system, and difficulty in transportation and installation is caused, thus being needed to be solved.

Disclosure of utility model

In order to solve the above problems, embodiments of the present application provide a battery pack housing, a liquid-cooled battery pack, and a modular energy storage system, which can reduce the overall weight of the energy storage system.

For this purpose, the following technical scheme is adopted in the embodiment of the application:

In a first aspect, an embodiment of the application provides a battery pack housing, which comprises a base and an upper cover, wherein the base is used for supporting and fixing a battery pack, the upper cover is connected to the base in a covering manner, a containing cavity with one side open is formed in the upper cover, the battery pack is located in the containing cavity when the upper cover is fixed on the base, the base is integrally a rectangular frame with an aluminum profile structure, and the upper cover is integrally formed in an injection molding manner.

In this embodiment, the upper cover adopts the plastics material to replace traditional metal material to the base of cooperation aluminium alloy structure can make whole energy storage unit reduce weight about 25kg, reduces energy storage unit transportation and installation difficulty degree, also reduces energy storage unit cost simultaneously. According to the application, the weight of the energy storage system is reduced from the aspect of shell design, and the light weight design of the energy storage system can be realized on the basis that the electric energy capacity of the energy storage system is not influenced.

As one possible embodiment, the base is formed with a groove, and the battery pack is mounted in the groove. Therefore, on the basis of further reducing the weight of the base, the fixing of the battery pack can be more stable.

In a second aspect, an embodiment of the present application provides a liquid-cooled battery pack, which is installed in the housing as described above, and includes at least two electric cells, wherein a liquid cooling plate is connected to the lower side of the electric cells, a refrigerant flows in the liquid cooling plate, and the refrigerant is used for guiding out heat of the battery pack.

In a third aspect, an embodiment of the application provides a modularized energy storage system, which comprises at least one energy storage unit, wherein the energy storage unit comprises at least one energy storage PCS module and a shell for installing and fixing the energy storage PCS module, the energy storage PCS module comprises a cascading PCS and a battery pack, the battery pack comprises at least two electric cores, and the battery pack is electrically connected with the cascading PCS.

In the embodiment, the modularized energy storage system adopts a cascading scheme, and an energy storage battery pack and a cascading PCS are integrated in an energy storage PCS module of one energy storage unit, so that the minimum particle unit of the energy storage system is reduced, each energy storage unit is integrated with the energy storage PCS module, dependence of the energy storage system on the consistency of a battery is greatly reduced, when an abnormality occurs in one energy storage unit, the abnormal energy storage unit automatically exits, the continuous operation of other energy storage units is not influenced, the utilization rate of the battery is fully improved, the service life of the battery is prolonged, and the overall utilization rate and stability of the system are improved.

As an implementation mode, 28 cells in the battery pack are arranged in series, and the energy storage PCS modules are provided with 4 cascaded PCS in the 4 energy storage PCS modules which are connected in series.

In the embodiment of the application, 28 sections of 280Ah lithium iron phosphate battery cells are connected in series to form a minimum battery pack, each battery pack is connected with a 12.5kW cascading PCS, each cascading PCS (power conversion system, a power conversion system, also called a converter) outputs 54V of voltage, and 4 cascading PCS cascading and then outputs 220V to form a 50kW/100kWh minimum energy storage unit. Compared with the traditional 100kW/215kWh energy storage system 240 power cells, the modularized energy storage system adopts 28 power cells to be connected in series for grouping, so that the number of the power cells of the energy storage unit is greatly reduced, the requirement on the consistency of the power cells is reduced, the utilization rate of the power cells is improved, the service life of the battery is prolonged, and the stability of the system is improved.

As an implementation mode, the shell comprises a base for supporting the energy storage PCS module and an upper cover for protecting the energy storage PCS module, wherein the upper cover is provided with a containing cavity, is detachably connected with the base, and is positioned in the containing cavity when the upper cover is fixed on the base.

In this embodiment, the base in the housing can support the energy storage PCS module, and the upper cover can completely cover the energy storage PCS module, thereby completely securing the energy storage PCS module to the housing. And the shell can effectively protect the energy storage PCS module, prevent the damage to the energy storage PCS module caused by the external environment, such as dust prevention, water prevention, vibration prevention and the like, thereby improving the reliability and stability of the system, preventing the displacement or damage of the energy storage PCS module caused by external factors, and improving the safety of the system. The upper cover is detachably connected with the base, so that maintenance and overhaul work can be conveniently performed, maintenance time and cost are reduced, and the energy storage PCS module can be replaced or adjusted quickly. The upper cover has the accommodation cavity, can effectively utilize the space for energy storage PCS module installs compactly wherein, practices thrift system installation space. The shell formed by matching the upper cover and the base can provide good protection performance for the energy storage PCS module, is convenient to maintain, has high space utilization and higher safety performance, and is a comprehensive design scheme of the shell of the energy storage PCS module.

As an implementation manner, the upper cover is integrally formed.

In this embodiment, upper cover integrated into one piece can promote the intensity of upper cover to further promote the security performance of casing.

As an implementation manner, the upper cover is made of any one of polypropylene, polycarbonate, polystyrene, polyamide, polyimide and polyvinyl chloride.

In this embodiment, the above-described materials can reduce the weight of the housing while compromising the structural strength of the upper cover, thereby reducing the weight of the energy storage unit as a whole, reducing transportation and installation costs, and facilitating system movement and handling. The upper cover is made of materials such as polypropylene, polycarbonate, polystyrene, polyamide, polyimide and polyvinyl chloride, and the like, so that the upper cover can bring various advantages such as light weight, corrosion resistance, insulation, cost effectiveness, good processability and the like, and is suitable for the design of the upper cover for protecting the energy storage PCS module.

As an implementation manner, the upper cover is provided with a reinforcing structure, and the reinforcing structure is a concave-convex line.

In the embodiment, the upper cover design scheme adopting the concave-convex lines as the reinforcing structure has the advantages of enhancing the structural strength, resisting deformation, attractive appearance, skid resistance, reducing the production cost and the like, is suitable for the upper cover design of the energy storage PCS module, and improves the overall performance and the reliability of the system.

As an implementation manner, the energy storage unit further includes a liquid cooling plate, the liquid cooling plate is connected with the battery pack, and a refrigerant flows in the liquid cooling plate, and the refrigerant is used for guiding out heat of the energy storage PCS module.

In the embodiment, the heat generated by the energy storage PCS module can be effectively taken away by the refrigerant flowing in the liquid cooling plate, so that the rapid and efficient heat dissipation is realized, the working temperature of the system is reduced, and the stable operation of the system is ensured.

As an implementation manner, a heat-conducting structural adhesive is arranged between the liquid cooling plate and the battery pack.

In the embodiment, the heat conduction structural adhesive can fill a tiny gap between the liquid cooling plate and the battery pack, reduce thermal resistance, promote heat conduction, help the liquid cooling plate to absorb heat generated by the battery pack more quickly and uniformly, improve heat dissipation efficiency and ensure stable operation of the system at a lower temperature. The heat conduction structural adhesive not only has good heat conduction performance, but also can increase the mechanical connection strength between the liquid cooling plate and the battery pack, reduce the fault risk caused by looseness or vibration, and improve the reliability and stability of the system.

As an implementation manner, the heat-conducting structural adhesive may be any one of silica gel or heat-conducting silicone grease.

In this embodiment, the silicone gel or the heat conductive silicone grease has good flexibility and filling property, can fill irregular surfaces and minute gaps, and contributes to improvement of the heat conductive effect.

As an implementation mode, one side of the liquid cooling plate is connected with a liquid cooling pipeline, the liquid cooling pipeline is communicated with a liquid cooling unit, and the liquid cooling unit inputs and outputs a refrigerant into the liquid cooling plate through the liquid cooling pipeline.

In the embodiment, the liquid cooling plate is connected with the liquid cooling pipeline and the liquid cooling unit, so that the circulating flow of the refrigerant can be realized, the heat generated by the energy storage PCS module is taken away rapidly, the heat dissipation efficiency is improved, and the stable operation of the system at a lower temperature is ensured. Meanwhile, the refrigerant is controlled by the liquid cooling unit, so that the internal temperature of the liquid cooling plate can be accurately regulated, the temperature is kept in a proper working temperature range, and the service lives of the system and the battery pack are prolonged.

As an implementation manner, the base structure is made of aluminum profiles.

In the embodiment, the aluminum profile is adopted as a base structure material, so that the energy storage system has multiple advantages of light weight design, good heat conduction performance, strong corrosion resistance, low manufacturing cost, environment friendliness, reproducibility and the like, is suitable for the base design in the energy storage system, and is beneficial to improving the performance and the service life of the energy storage system.

In view of the above, embodiments of the present application have at least one of the following advantages:

1. the modularized energy storage system provided by the embodiment of the application can realize the minimum granularity application of the energy storage unit, and reduce the requirement of the energy storage system on the consistency of the battery cells;

2. The liquid cooling battery pack provided by the embodiment of the application can solve the heat dissipation problem of the high-capacity battery pack and the cascade PCS;

3. the shell provided by the embodiment of the application can solve the problem of fixing the structure of the energy storage PCS module;

4. The shell provided by the embodiment of the application can realize the lightweight design of the energy storage unit and solve the problem of overweight energy storage products.

Drawings

FIG. 1 illustrates a simplified schematic diagram of a modular energy storage system provided by an embodiment of the present application;

FIG. 2 is an exploded view of a portion of a housing provided in an embodiment of the present application;

FIG. 3 is a schematic diagram of an energy storage PCS module and a base mounting structure provided in an embodiment of the present application;

Fig. 4 is a schematic view of an upper cover structure according to an embodiment of the present application;

In the figure, 100 parts of modularized energy storage system, 1 part of energy storage unit, 11 parts of liquid cooling plate, 111 parts of liquid inlet pipe, 112 parts of liquid outlet pipe, 200 parts of electric network or load, 2 parts of energy storage PCS module, 21 parts of cascade PCS, 22 parts of battery pack, 221 parts of electric core, 222 parts of insulating sealing cover, 223 parts of binding belt, 224 parts of interval fireproof blanket, 3 parts of shell, 31 parts of base, 311 parts of groove, 312 parts of angle steel, 313 parts of end plate, 314 parts of positive electrode output terminal, 315 parts of negative electrode output terminal, 316 parts of battery management unit, 32 parts of upper cover, 321 parts of accommodating cavity, 322 parts of flanging, 323 parts of yielding hole, 324 parts of concave-convex grain.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

In the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed, mechanically connected, electrically connected, directly connected, indirectly connected through an intervening medium, or in communication between two elements or in an interaction relationship between two elements, unless otherwise explicitly specified. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

The following examples are given for a more complete understanding of the present application. These examples are provided to illustrate embodiments of the application in particular, and should not be construed as limiting the scope of the application in any way.

Fig. 1 shows a simplified schematic configuration of a modular energy storage system according to an embodiment of the present application. Referring to fig. 1, the modular energy storage system 100 includes a plurality of energy storage units 1, wherein the plurality of energy storage units 1 can increase the capacity of the modular energy storage system 100, and the specific number of the energy storage units 1 can be adjusted according to design requirements, which is not limited in the present application. The energy storage unit 1 is interconnected with the grid/load 200 for taking electrical energy from the grid side and providing electrical energy to the grid/load 200.

With continued reference to fig. 1, the energy storage unit 1 includes at least one energy storage PCS (power conversion system, power conversion system, also known as a converter) module 2 and a housing 3 for mounting the stationary energy storage PCS module 2. The energy storage PCS module 2 comprises a cascade PCS21 and a battery pack 22, wherein the battery pack 22 comprises at least two electric cores 221, and the battery pack 22 is electrically connected with the cascade PCS 21.

It should be noted that, in this embodiment, the cascaded PCS21 is composed of hardware such as an insulated gate bipolar transistor (insulated gate bipolar transistor, IGBT), a printed circuit board (printed circuit board, PCB) and a wire and cable, and is used to provide a cascaded multi-level topology circuit for the battery pack 22, and under this topology circuit, the energy storage system can reduce or eliminate the parallel connection situation of the energy storage units 1 to the greatest extent, so that the energy storage units 1 are mutually independent, the circulation phenomenon of the battery cell 221 and the battery pack 22 is reduced or eliminated, the problem caused by the battery consistency in the energy storage system is weakened, the cycle life of the battery pack 22 is prolonged, and the safety risk of production operation is reduced. The implementation of the cascaded PCS21 specific topology circuit is a prior art, and will not be described herein.

It should be appreciated that the cascaded PCS21 mode of operation primarily includes grid-connected, off-grid and hybrid modes. In grid-tie mode, cascaded PCS21 achieves bi-directional energy conversion between energy storage battery 22 and the grid, charging or discharging battery 22. In the off-grid mode, the cascaded PCS21 can provide alternating current power meeting the power quality requirement of the power grid for the local partial load according to actual requirements. In hybrid mode, cascaded PCS21 is capable of switching between grid-tie mode and off-grid mode. The main functions of the cascade PCS21 include stabilizing power, protecting information, protecting protection and the like, and the cascade PCS21 determines the output power quality and dynamic characteristics and also influences the service life of the battery to a great extent.

In this way, the modularized energy storage system adopts a cascading scheme, and the energy storage battery pack 22 and the cascading PCS21 are integrated in the energy storage PCS module 2 of one energy storage unit 1, so that the minimum particle unit of the energy storage system is reduced, each energy storage unit 1 is integrated with the energy storage PCS module 2, the dependence of the energy storage system on the consistency of the battery is greatly reduced, when an abnormality occurs in one energy storage unit 1, the abnormal energy storage unit 1 automatically withdraws, the continuous operation of other energy storage units 1 is not influenced, the utilization rate of the battery is fully improved, the service life of the battery is prolonged, and the overall utilization rate and the stability of the system are improved.

Referring to fig. 2 and 3, in a specific embodiment, the energy storage PCS modules 2 are provided with 4, 4 energy storage PCS modules 2 are arranged side by side at equal intervals, and cascade PCS21 of the 4 energy storage PCS modules 2 are connected in series with each other. While the cells 221 in the battery pack 22 are provided with 28 sections, and the 28 cells 221 are arranged in series. It should be noted that, since the lithium ion battery has the advantages of high energy density, fast response speed and long discharge time, the battery cell 221 in the present embodiment is a 280Ah lithium iron phosphate battery cell 221. Specifically, each battery pack 22 is formed by connecting 28 sections of 280Ah lithium iron phosphate battery cells 221 in series, each battery pack 22 is connected with a 12.5kW cascade type PCS21, each cascade type PCS21 outputs 54V of voltage, and 4 cascade type PCS21 outputs 220V after cascade, so that a 50kW/100kWh minimum energy storage unit 1 is formed. Compared with the traditional grouping of the power cells 221 of the 100kW/215kWh energy storage system 240, the battery pack 22 adopts 28 power cells 221 to be connected in series and grouped, so that the number of the power cells 221 of the energy storage unit 1 is greatly reduced, the consistency requirement on the power cells 221 is reduced, the utilization rate of the power cells 221 is improved, the service life of a battery is prolonged, and the stability of the energy storage system is improved.

In one embodiment, an insulating cover 222 is covered on the upper side of the battery pack 22 to facilitate the parallel series grouping of the cells 221 of the same battery pack 22. In order to make the fixation between the cells 221 of the same battery pack 22 more stable, there are two binding bands 223 outside Zhou Bangza of the whole after the cells 221 of the same battery pack 22 are arranged side by side in series, it being understood that the binding bands 223 are insulating binding bands 223. Meanwhile, the battery cells 221 in the same battery pack 22 form a group in pairs, and a spacing fireproof blanket 224 is arranged between the group formed by two battery cells 221 and the group formed by the other two battery cells 221, and the spacing fireproof blanket 224 can play a role in heat insulation and flame retardance, so that the safety of the battery pack 22 in use is improved.

Referring to fig. 3 and 4, the housing 3 includes a base 31 for supporting the energy storage PCS module 2 and an upper cover 32 for protecting the energy storage PCS module 2. The upper cover 32 has a receiving chamber 321, and the upper cover 32 is detachably connected with the base 31. The upper cover 32 is connected to the base 31 in a closing manner, and the energy storage PCS module 2 is located in the receiving cavity 321 when the upper cover 32 is fixed to the base 31.

Illustratively, the removable connection between the upper cover 32 and the base 31 may be any one of adhesive, snap fit, or screw fit. For example, the upper cover 32 and the base 31 can be adhered together by structural adhesive, or the opening edge of the upper cover 32 is provided with a clamping hook, a clamping groove is arranged at the position corresponding to the clamping hook at the peripheral edge of the base 31, the clamping hook and the clamping groove are mutually matched to clamp the upper cover 32 on the base 31, or the flange 322 extends outwards from the edge of the upper cover 32 facing the opening edge of the base 31, a threaded hole is formed at the contact position of the flange 322 and the base 31, and a bolt is screwed in the threaded hole, so that the upper cover 32 is screwed on the base 31.

Referring to fig. 3, a groove 311 is formed on the upper surface of the base 31, and four energy storage PCS modules 2 are fixed in the groove 311 of the base 31 after being arranged side by side, and the groove 311 can make the fixation of the energy storage PCS modules 2 more stable. In addition, the whole base 31 is a rectangular frame constructed by aluminum profile materials, and the aluminum profile has the characteristics of light weight, corrosion resistance, easiness in processing, good heat conduction performance and the like, so that the whole weight of the energy storage system is obviously reduced while the shell 3 has strength.

Optionally, an end plate 313 is detachably connected to the base 31 through angle steel 312, and the end plate 313 is located on one side of the energy storage PCS module 2. Illustratively, an insulated output terminal is provided on the end plate 313 and is electrically connected to the energy storage PCS module 2 via a flat cable. The insulated output terminals include a positive output terminal 314 and a negative output terminal 315, through which the energy storage unit 1 is electrically connected to the grid/load 200.

In one embodiment, the battery management unit 316 is provided on the end plate 313, and the battery management unit 316 mainly manages the charge and discharge protection of the battery pack 22. The battery management unit 316 can ensure that the voltage difference between the unit cells 221 is smaller than the set value when the battery pack 22 is charged, so as to realize the uniform charging of the unit cells 221 of the battery pack 22, and effectively improve the charging effect in the serial charging mode. Meanwhile, the battery management unit 316 detects overvoltage, undervoltage, overcurrent, short circuit and overtemperature states of each single cell 221 in the battery pack 22, and protects and prolongs the service life of the battery. The specific implementation of the battery management unit 316 can refer to the existing design, and the present application is not described herein.

It should be noted that, correspondingly, a yielding hole 323 for partially installing the end plate 313 is formed on one side of the upper cover 32, and the yielding hole 323 enables the structure on one side of the end plate 313 to be displayed on the outer side of the accommodating cavity 321 of the upper cover 32, so that the operation of each functional part on the end plate 313 by a worker is facilitated.

Referring to fig. 4, in one embodiment, the longitudinal section of the accommodating cavity 321 of the upper cover 32 is configured in a trapezoid shape, so that the space can be effectively utilized while accommodating the energy storage PCS module 2, so that the energy storage PCS module 2 is installed compactly therein, and the installation space of the system is saved. In another possible embodiment, the longitudinal section of the accommodating cavity 321 may be an inverted U-shape, which is not strictly limited herein, and the designer may specifically design the shape of the accommodating cavity 321 according to the structure of the energy storage PCS module 2.

In order to enable the upper cover 32 to have high strength, the upper cover 32 is constructed as an integral molding. Illustratively, the upper cover 32 may be integrally molded by injection molding. For example, the upper cover 32 is made of any one of polypropylene, polycarbonate, polystyrene, polyamide, polyimide, and polyvinyl chloride. The polypropylene has good mechanical properties, corrosion resistance and high temperature resistance, and is suitable for manufacturing the shell of the energy storage system. The polycarbonate has excellent transparency, impact resistance and heat resistance, and is suitable for use in a battery pack case 3 requiring a transparent appearance or having high requirements for impact resistance. The polystyrene has good processability and surface gloss, and is suitable for manufacturing the shell of the energy storage system. Polyamides have excellent mechanical properties, abrasion resistance and heat resistance, and are also selected for the battery case 3 in some cases where strength and durability are required. Polyimide has extremely high heat resistance, chemical resistance and mechanical properties, and is suitable for use in the battery pack case 3 in a high temperature environment. The polyvinyl chloride has good processability, insulating property and corrosion resistance, and meanwhile, the manufacturing cost of the polyvinyl chloride is low, so that the overall manufacturing cost of the energy storage system can be reduced.

In some examples, the upper cover 32 is provided with a reinforcing structure that is a relief texture 324 to accommodate the integrally formed configuration. The concave-convex lines 324 can effectively increase the structural strength of the upper cover 32, so that the upper cover is more firm and durable, and the compression resistance and bearing capacity of the integral shell 3 are improved. Meanwhile, the arrangement of the concave-convex grains 324 can effectively disperse external impact or extrusion force, reduce the possibility of structural deformation, maintain the stability of the shape of the upper cover 32 and prolong the service life of the shell 3. Moreover, compared with other complex reinforcing structures, the concave-convex grain 324 is simple in design, is suitable for an integrally formed structural mode, is easy to manufacture, can effectively reduce production cost and improves production efficiency.

So, upper cover 32 adopts the plastics material to replace traditional metal material to the base 31 of cooperation aluminium alloy structure can make whole energy storage unit 1 reduce weight about 25kg, also reduces energy storage unit 1 cost simultaneously, realizes energy storage system's lightweight design.

Since the cell 221, which is a lithium battery, has a range requirement for the operating temperature of the energy storage system, it is necessary to control the temperature inside the energy storage system housing 3. In one embodiment, referring to fig. 1 and 2, the energy storage unit 1 further includes a liquid cooling plate 11, the liquid cooling plate 11 is connected with the battery pack 22, and a refrigerant flows in the liquid cooling plate 11, where the refrigerant is used for guiding out heat of the energy storage PCS module 2. Illustratively, the liquid cooling plate 11 is positioned at the bottom of the battery pack 22 and mounted within the recess 311 of the support, it being understood that the liquid cooling plate 11 can cover four energy storage PCS modules 2. In another possible embodiment, the liquid cooling plate 11 can also rest against the side wall of the battery pack 22 or an insulating cover 222 on the upper side of the battery pack 22. Or, the liquid cooling plates 11 are disposed on six side walls of the integrated structure formed by the side-by-side four energy storage PCS modules 2, which is not limited herein, so long as a sufficient contact area exists between the liquid cooling plates 11 and the energy storage PCS modules 2.

In one embodiment, in order to further improve the heat exchange efficiency between the liquid cooling plate 11 and the energy storage PCS module 2, a heat conductive structural adhesive (not shown) is disposed between the liquid cooling plate 11 and the battery pack 22. The heat conduction structural adhesive can fill the tiny gap between the liquid cooling plate 11 and the battery pack 22, reduce thermal resistance, promote heat conduction, help the liquid cooling plate 11 to absorb heat generated by the battery pack 22 more quickly and uniformly, and improve heat dissipation efficiency. Optionally, the heat-conducting structural adhesive may be any one of silica gel or heat-conducting silicone grease. The silica gel or the heat-conducting silicone grease not only has good heat-conducting property, but also can increase the mechanical connection strength between the liquid cooling plate 11 and the battery pack 22, reduce the fault risk caused by loosening or vibration, and improve the reliability and the stability of the system.

Referring to fig. 2 and 3, a liquid cooling pipeline is connected to one side of the liquid cooling plate 11, and the liquid cooling pipeline is connected to a liquid cooling unit (not shown in the drawings, for example, may include a hydraulic pump and a liquid cooling machine), the liquid cooling pipeline includes a liquid inlet pipe 111 and a liquid outlet pipe 112, the liquid inlet pipe 111 and the liquid outlet pipe 112 are installed on the base 31, and the liquid cooling unit inputs and outputs a refrigerant into the liquid cooling plate 11 through the liquid inlet pipe 111 and the liquid outlet pipe 112. Illustratively, the refrigerant is a cooling liquid, and the cooling liquid flows in a unidirectional manner in the liquid cooling plate 11 and takes away heat of the battery pack 22, so as to achieve the effect of cooling the energy storage PCS module 2.

The modularized energy storage system provided by the embodiment of the application is mainly applied to the battery energy storage industry, the power transmission and transformation industry, the petroleum exploration industry, the sewage treatment industry, the data center, the communication base station industry and the like, and can be used for adjusting and balancing electric energy in the fields of power grid peak shaving, standby electric power, micro-power grids and the like. Meanwhile, the modularized energy storage system can provide electric energy for uninterruptible power supplies (uninterruptible power supply, UPS), charging piles (ELECTRIC VEHICLE CHARGER, EV CHARGER), power grid side-power transmission and distribution equipment ((power transmission and distribution equipment: power transmission and distribution equipment, PTD), (medium-voltage power distribution: medium voltage distribution, MVD), (active power filter: active power filter, APF), (static var generator: STATIC VAR generator, SVG)), outdoor cabinets, base stations and the like.

Finally, the above embodiments are only used to illustrate the technical solution of the present application. It will be appreciated by those skilled in the art that, although the application has been described in detail with reference to the foregoing embodiments, various modifications may be made to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features thereof. Such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions in the various embodiments of the application.

Claims (10)

1. A battery pack housing, comprising: A base, the base being used to support and fix the battery pack; and An upper cover, the upper cover can be connected to the base in a covering manner, and a receiving cavity with an opening on one side is formed inside the upper cover, and when the upper cover is fixed on the base, the battery pack is located in the receiving cavity; The base is a rectangular frame made of aluminum profiles; the upper cover is an integrally formed injection molded structure. 2 . The housing according to claim 1 , wherein a groove is formed on the base, and the battery pack is installed in the groove. 3 . The housing according to claim 1 , wherein the upper cover is provided with a reinforcement structure, and the reinforcement structure is a concave-convex pattern. 4. The housing according to any one of claims 1 to 3, characterized in that the upper cover is made of any one of polypropylene, polycarbonate, polystyrene, polyamide, polyimide and polyvinyl chloride. 5. A liquid-cooled battery pack, characterized in that it comprises a shell as described in any one of claims 1 to 4 and at least two battery cells, wherein a liquid cooling plate is connected to the lower side of the battery cell, a refrigerant flows in the liquid cooling plate, and the refrigerant is used to extract heat from the battery pack. 6 . The battery pack according to claim 5 , wherein a heat-conducting structural adhesive is provided between the liquid cooling plate and the battery pack. 7. The battery pack according to claim 5, characterized in that a liquid cooling pipeline is connected to one side of the liquid cooling plate, the liquid cooling pipeline is connected to a liquid cooling unit, and the liquid cooling unit inputs and outputs refrigerant to the liquid cooling plate through the liquid cooling pipeline. 8. The battery pack according to claim 5 is characterized in that an insulating cover is provided on the battery pack, and the insulating cover is used to fix the multiple battery cells; and at least one binding strap is provided on the periphery of the battery pack, and the binding strap is used to fix the multiple battery cells connected in series. 9. A modular energy storage system, comprising: At least one energy storage unit, the energy storage unit comprising at least one energy storage PCS module and a shell as described in any one of claims 1-4; wherein the energy storage PCS module comprises a cascaded PCS and a battery pack as described in any one of claims 5-8, the battery pack comprising at least two battery cells; the battery pack is electrically connected to the cascaded PCS. 10. The energy storage system according to claim 9, characterized in that the battery pack is provided with 28 battery cells, and the 28 battery cells are arranged in series; and the energy storage PCS modules are provided with 4, and the cascaded PCSs in the 4 energy storage PCS modules are connected in series.