CN216450741U

CN216450741U - Battery box

Info

Publication number: CN216450741U
Application number: CN202121265653.4U
Authority: CN
Inventors: 张建平; 黄春华
Original assignee: Aulton New Energy Automotive Technology Co Ltd
Current assignee: Aulton New Energy Automotive Technology Co Ltd
Priority date: 2020-06-05
Filing date: 2021-06-07
Publication date: 2022-05-06
Anticipated expiration: 2031-06-07

Abstract

The utility model discloses a battery box, which comprises a box body and a battery assembly arranged in the box body, wherein the box body comprises a lower box body made of a composite material, the composite material is one of an SMC (sheet molding compound) composite material, a mixture of an SMC composite material and aerogel, a PCM composite material, a mixture of a PCM composite material and aerogel and a carbon fiber material, and the internal space of the box body is filled with heat-conducting glue. The heat conducting glue can diffuse the heat in the box body and level the temperature of each area in the box body. The heat of the higher department of box inside temperature is to the diffusion of lower department of temperature under the effect of heat conduction glue to this reduces the difference in temperature between the battery pack, guarantees that the temperature of each part of battery pack is the same as far as possible, improves battery pack's life, makes the efficiency maximize of battery box.

Description

Battery box

This application claims priority to chinese patent application 202021028135.6, filed on even 2020, 06, 05. The present application refers to the above-mentioned chinese patent application in its entirety.

Technical Field

The utility model relates to the field of electric automobiles, in particular to a battery box.

Background

Along with social development and scientific and technological progress, electric vehicles are more and more popular with consumers, the battery box is used as a power source of the electric vehicle, the influence of the environmental temperature is large, the battery cores are influenced by overhigh and overlow temperature in the battery box, and the heating and the generated heat of the battery cores at different positions can be different according to the positions of the battery cores in the battery box, so that the temperature difference among the battery cores is large, the power supply condition of the electric vehicle is influenced by overhigh and overlow temperature of the battery cores, and the temperature among a plurality of battery cores needs to be balanced.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defect that the temperature difference of a plurality of battery cores in a battery box is large in the prior art, and provides the battery box.

The utility model solves the technical problems through the following technical scheme:

the battery box comprises a box body and a battery assembly arranged in the box body, the box body comprises a lower box body made of a composite material, the composite material is one of SMC composite material, a mixture of SMC composite material and aerogel, PCM composite material, a mixture of PCM composite material and aerogel and a carbon fiber material, and heat-conducting glue is filled in the inner space of the box body.

In this scheme, the heat conduction glue can make the inside heat diffusion of box, evens up the temperature in each region of box inside. The heat of the higher department of box inside temperature is to the diffusion of lower department of temperature under the effect of heat conduction glue to this reduces the difference in temperature between the battery pack, guarantees that the temperature of each part of battery pack is the same as far as possible, improves battery pack's life, makes the efficiency maximize of battery box.

Preferably, the inside of the box body is further provided with a phase change temperature adjusting part, the periphery of the phase change temperature adjusting part is filled with the heat conducting glue, and the phase change temperature adjusting part is used for adjusting the temperature change in the box body.

In this scheme, the phase transition piece that adjusts the temperature can absorb heat or release heat according to the inside temperature of box to this temperature variation in to the box adjusts, thereby can be with the inside temperature control of box within the suitable scope, makes the efficiency maximize of battery box.

Preferably, the phase change temperature adjusting pieces are uniformly arranged inside the box body.

In this scheme, evenly set up the phase transition piece that adjusts the temperature in the inside of box, each part that makes in the box can both accept the heat absorption of phase transition piece and release heat to this guarantees the temperature equilibrium of box inside.

Preferably, the material of the phase-change temperature adjusting element is a phase-change material or a mixture of the phase-change material and an aerogel material.

In the scheme, the phase-change material is a substance which is common at present and can be used for absorbing and releasing heat, is easy to obtain and has low manufacturing cost.

Preferably, the box body further comprises a reinforcing rib, and the reinforcing rib is arranged on the lower box body and is integrally injection-molded with the lower box body.

In this scheme, the strengthening rib is used for strengthening the intensity of box down, has solved combined material's the not enough problem of box intensity down, has improved the holistic rigidity of battery box, has satisfied the operation requirement of battery box.

Preferably, the box body further comprises a housing, and the lower box body is arranged on the inner wall of the housing.

In this scheme, the casing is used for strengthening the intensity of box down, makes the box body can bear battery pack more steadily down.

Preferably, the lower box body comprises an outer box body and an inner box body, and an aerogel layer is pressed between the outer box body and the inner box body.

In this scheme, the lower box adopts the structure of multilayer box, can strengthen the intensity of box down, and aerogel layer plays thermal-insulated effect, avoids external high temperature or low temperature to the inside influence of battery box, also can reduce by the inside heat that gives off to the external world of box, guarantees the inside temperature of box.

Preferably, the battery box further comprises at least one mounting strip, the mounting strip is fixed on the outer peripheral surface of the lower box body, and the mounting strip is used for mounting at least one functional piece; the functional part is one of a guide mechanism, a lock shaft and an electric connector, the guide mechanism is used for guiding the battery box in the replacement process, the lock shaft is used for being matched with a locking mechanism fixed on the electric vehicle to lock the battery box, and the electric connector is used for being electrically connected with a vehicle-end electric connector or a station-end electric connector.

In the scheme, the battery box realizes the movement guiding, locking and electric connection of the battery box through each functional piece.

Preferably, the battery box further comprises a heat exchange pipeline, the heat exchange pipeline is installed in the box body and is arranged corresponding to the battery assembly, and the heat exchange pipeline is used for circulating and circulating fluid to achieve heat exchange between the heat exchange pipeline and the battery assembly.

In the scheme, the heat exchange pipe is used for circulating and circulating fluid to realize heat exchange with the battery component.

The positive progress effects of the utility model are as follows: the heat conducting glue can diffuse the heat in the box body and level the temperature of each area in the box body. The heat of the higher department of the inside temperature of box is spread to the lower department of temperature under the effect of heat conduction glue to this reduces the difference in temperature between the battery pack, guarantees that the temperature of each part of battery pack is the same as far as possible, improves battery pack's life, makes the efficiency maximize of battery box.

Drawings

Fig. 1 is a schematic structural view of a battery box according to embodiment 1 of the present invention.

Fig. 2 is a schematic view of the internal structure of a battery case according to embodiment 1 of the present invention.

Fig. 3 is a schematic structural view of an upper case of the battery case shown in fig. 1.

Fig. 4 is a schematic structural view of the battery box shown in fig. 1 with an upper box body hidden.

Fig. 5 is a partially enlarged view of the battery case shown in fig. 4.

Fig. 6 is a schematic structural view of a lower case of the battery case shown in fig. 1.

Fig. 7 is a schematic view of another angle structure of the lower case shown in fig. 6.

Fig. 8 is a schematic structural view of a case of the battery case shown in fig. 1.

Fig. 9 is a sectional view of the battery case shown in fig. 1.

Fig. 10 is a partially enlarged view of the battery case shown in fig. 9.

Fig. 11 is a schematic structural view of a mounting bar, a guide mechanism and a lock shaft of the battery case shown in fig. 1.

Fig. 12 is a schematic structural view of the guide mechanism shown in fig. 11.

Fig. 13 is a schematic cross-sectional view of the guide mechanism shown in fig. 12.

Fig. 14 is a schematic view of the lock shaft shown in fig. 11.

Fig. 15 is a cross-sectional view of the latch spindle of fig. 14.

Fig. 16 is a schematic view of the internal structure of a battery case according to embodiment 2 of the present invention.

Fig. 17 is a schematic structural view of a case and reinforcing ribs of a battery box according to embodiment 3 of the present invention.

Fig. 18 is a schematic view of the internal structure of a battery case according to embodiment 4 of the present invention.

Fig. 19 is a schematic view showing an internal structure of the battery case shown in fig. 18 with a battery cell hidden.

Fig. 20 is a schematic structural view of a battery box according to embodiment 5 of the present invention.

Fig. 21 is a schematic structural view of the battery case shown in fig. 20 with an upper case body hidden.

Fig. 22 is a bottom schematic view of the battery box shown in fig. 20.

Fig. 23 is a schematic view showing the structure of the lower case and reinforcing ribs of the battery case shown in fig. 20.

Fig. 24 is a schematic structural view of the lower case, the reinforcing ribs, and the outer frame of the battery case shown in fig. 20.

Fig. 25 is a schematic structural view of the lower case body, the reinforcing ribs, the outer frame, and the floor shield of the battery case shown in fig. 20.

Fig. 26 is a sectional view of the battery case shown in fig. 20.

Fig. 27 is a partially enlarged view of the battery case shown in fig. 26.

FIG. 28 is a schematic sectional view of a lower case according to embodiment 6 of the present invention.

Description of the reference numerals:

upper box body 1

Projection 11

Lower box body 2

Grid structure 21

Outer case 22

Inner layer box body 23

Aerogel layer 24

Heat-conducting glue 3

Housing 4

Reinforcing rib 5

Sealing strip 6

Connecting bolt 7

Mounting bar 8

Guide mechanism 9

Guide block 91

Elastic member 92

Bump 93

Installation space 94

Lock shaft 10

Shaft fixing part 101

Shaft body 102

Inductive element 103

Shaft sleeve 104

Electrical connector 20

Battery cell 30

Phase change temperature regulating member 40

Outer frame 50

Bottom guard board 60

Detailed Description

The utility model is further illustrated by the following examples, which are not intended to limit the scope of the utility model.

Example 1

The embodiment provides a battery box, and this battery box is applied to the electric automobile field, provides power for electric automobile. The battery box comprises an external box body, a battery assembly arranged in the box body and used for storing electric power, and further comprises components arranged on the peripheral surface of the box body and used for installing and moving the battery box, and an electric connector electrically connected with the battery box and an electric vehicle or a charging station.

As shown in fig. 1 to 15, the case of the battery case includes an upper case 1 and a lower case 2, the upper case 1 is covered on the lower case 2 to form an inner space of the case, and the battery pack is placed in the inner space and fixed to the inner surface of the lower case 2 by an adhesive. The adhesive used to fix the battery pack to the lower case 2 is known in the art and will not be described herein.

The lower box body 2 is made of composite materials, the composite materials are SMC composite materials, mixtures of SMC composite materials and aerogel, PCM composite materials, mixtures of PCM composite materials and aerogel and carbon fiber materials, the total weight of the box body can be reduced by adopting the lower box body 2 made of the composite materials, the influence of the environmental temperature on the lower box body 2 made of the composite materials is relatively small, and the temperature inside the box body can be well maintained.

The smc (sheet molding compound) composite material may be conventional in the art and is one of glass fiber reinforced plastics, and the main raw material is composed of GF (special yarn), MD (filler) and various auxiliaries. The lower case 2 made of the SMC composite material has excellent electrical insulation, mechanical properties, thermal stability, and chemical resistance to corrosion.

Pcm (phase Change material) composite materials are conventional in the art and are phase Change materials, which refer to materials that Change state of matter and provide latent heat at a constant temperature. The lower box body 2 made of PCM composite material has high latent heat of fusion, so that the lower box body can store or emit more heat in phase change; the phase change process has good reversibility, small expansion and contraction, and less supercooling or overheating phenomena; large heat conductivity coefficient, high density and high specific heat capacity.

Carbon Fiber materials, namely CFRP (Carbon Fiber Reinforced Polymer/Plastic) composite materials, are conventional in the field, are formed by converting organic fibers through a series of heat treatment, are inorganic high-performance fibers with high Carbon content, are novel materials with excellent mechanical properties, have the inherent characteristics of Carbon materials, have the soft processability of textile fibers, and are new-generation reinforcing fibers. The lower case 2 made of the carbon fiber material has high strength, excellent heat resistance and thermal shock resistance, low thermal expansion coefficient, small heat capacity, small specific gravity and strong corrosion resistance.

The lower box body 2 made of the composite material is formed in one step, so that the processing precision is high, the heat preservation performance is good, the flame retardance is good, and the forming structure is high; the heat insulation property of the composite material can reduce the influence of the environmental temperature on the temperature in the battery box, effectively solve the problem of condensation in the battery box and effectively avoid the safety risks of insulation failure and the like caused by condensed water; the inner container made of the composite material can also improve the corrosion resistance of the battery box and prolong the service life of the battery box.

In order to improve the heat preservation and insulation effect of the lower box body 2, aerogel can be added into the SMC composite material and the PCM composite material. Wherein, when the composite material of the lower box body 2 is a mixture of SMC composite material and aerogel, the mass ratio of aerogel to SMC composite material is preferably (0.5:99.5) - (1.5: 98.5); when the composite material of the lower box body 2 is a mixture of the PCM composite material and the aerogel, the mass ratio of the aerogel to the PCM composite material is (0.5:99.5) - (1.5: 98.5). The aerogel mainly plays flame retardant, fire prevention and heat retaining effect, and a small amount of aerogel can play fine effect, and SMC combined material or PCM combined material can strengthen the intensity of box 2 down as the main material. The aerogel of above-mentioned proportion can be when guaranteeing box 2's intensity down, and the thermal-insulated fire prevention effect of heat preservation of box 2 avoids battery pack to fire the burning because of the high temperature down.

As shown in fig. 2, the internal space of the case is filled with a heat conductive paste 3, and the heat conductive paste 3 can diffuse the heat inside the case and level the temperature of each region inside the case. The heat of the higher department of box inside temperature is to the lower department diffusion of temperature under the effect of heat conduction glue 3 to this reduces the difference in temperature between the battery pack, guarantees that the temperature of each part of battery pack is the same as far as possible, improves battery pack's life, makes the efficiency maximize of battery box.

The thermal conductive adhesive 3 is filled after various elements inside the lower box body 2 are installed, the thermal conductive adhesive 3 is filled by means of an adhesive filling tool, the lower end of the adhesive filling tool is connected with the upper end of the lower box body 2, the inner surface of the adhesive filling tool and the inner surface of the lower box body 2 can form a sealed adhesive filling space, the adhesive filling space is filled with the thermal conductive adhesive 3 from an adhesive filling hole of the adhesive filling tool, and the periphery of the battery assembly and the phase-change temperature regulating part 40 is filled with the thermal conductive adhesive 3. The amount of the thermal conductive paste 3 to be filled is preferably at least such that the filling height of the thermal conductive paste 3 is equal to or slightly greater than the height of the battery assembly, so that the heat can be dissipated also from the upper end of the battery assembly through the thermal conductive paste 3. After the heat-conducting glue 3 is cured, the glue pouring tool can be detached, and then the upper box body 1 and the lower box body 2 are fixedly connected to realize the sealing of the box body.

The heat-conducting glue 3 poured into the glue filling space is the heat-conducting glue 3 with the calculated specific heat capacity, the specific heat capacity of the heat-conducting glue 3 is related to the specifications of the battery assembly and the box body, and the calculation formula for specifically calculating the specific heat capacity of the heat-conducting glue 3 belongs to the prior art and is not described herein any more.

The battery box still includes the heat preservation in this embodiment, and the heat preservation is fixed on the surface of box for keep the inside temperature of box, reduce and give off to external heat by the box is inside. The heat preservation layer in this embodiment is fixed on the surface of box through the adhesive, and the heat preservation layer is made by aerogel felt, and aerogel felt is a heat preservation and insulation material, acquires conveniently and with low costs. The adhesive used for fixing the insulating layer and the box body belongs to the prior art in the field and is not described in detail herein.

The heat preservation layer comprises an upper heat preservation layer and a lower heat preservation layer, the upper heat preservation layer is arranged on the inner surface of the upper box body 1 in the box body, and the lower heat preservation layer is coated on the outer surface of the lower box body 2. Since the battery pack is fixed to the inner surface of the lower case 2 by an adhesive and the insulating layer is made of aerogel felt, if the lower insulating layer is attached to the inner surface of the lower case 2, the battery pack is not firmly fixed to the lower case 2, and thus the lower insulating layer is disposed on the outer surface of the lower case 2 in this embodiment.

As shown in fig. 4 to 6, the inner bottom surface of the lower case 2 has a lattice structure 21, and the lattice structure 21 forms a receiving space for receiving a plurality of battery modules. A plurality of battery components are respectively arranged in the grid structure 21, so that the battery components can be conveniently arranged and positioned, and the installation precision is improved. The grid bars of the grid structure 21 correspond to reinforcing ribs added to the lower case 2, and further enhance the strength of the lower case 2. Because the grid structure 21 has certain thickness, certain gaps are formed among the battery components, heat of the battery components is convenient to dissipate, and the influence on the service performance and the service life of the battery components caused by overheating of the battery components is avoided. The battery assembly may be a battery module formed by a plurality of battery cells 30, and in the installation process of the battery box, the battery module is formed by the plurality of battery cells 30 and then placed in the grid structure 21. The number of the battery modules needing to be installed is small, the installation process of the battery box can be simplified, and the installation mode is simple and quick.

The battery box also comprises a heat exchange pipeline, the heat exchange pipeline is arranged in an inner space formed by the box body and is arranged corresponding to the battery component fixed in the lower box body 2, and the heat exchange pipeline is used for circulating fluid to realize heat exchange with the battery component.

Still be provided with casing 4 in the outside of box 2 down, box 2 sets up on the inner wall of casing 4 down, and casing 4 can strengthen box 2's intensity down, remedies the not high problem of the intensity of box 2 down of being made by combined material, makes the bulk strength of box can satisfy actual demand. The housing 4 may be made of metal, such as aluminum, steel, etc. When the shell 4 is made of steel, the shell 4 can be formed by stamping; when the housing 4 is made of aluminum, the housing 4 may be formed by aluminum profile welding or aluminum casting.

As shown in fig. 8, the box further includes a reinforcing rib 5, and the reinforcing rib 5 is disposed on the housing 4. The strength of the housing 4 can be enhanced by the reinforcing ribs 5, thereby enhancing the overall strength of the case.

Wherein the reinforcing ribs 5 may be integrally formed with the housing 4. When the shell 4 and the reinforcing ribs 5 are made of steel, the shell 4 and the reinforcing ribs 5 can be integrally formed in a stamping mode; when the shell 4 and the reinforcing ribs 5 are made of aluminum, the shell 4 and the reinforcing ribs 5 can be formed by aluminum profile welding or aluminum casting.

The manufacturing method of the box body comprises the following steps:

s11, coating the adhesive on the inner surface of the shell 4;

s12, the lower case 2 is placed in the housing 4 so that the outer surface of the lower case 2 is bonded to the inner surface of the housing 4.

When the shell 4 and the reinforcing ribs 5 are integrally formed, the grooves corresponding to the reinforcing ribs 5 are also formed on the outer bottom surface of the lower box body 2 in an injection molding mode. When the case 4 is bonded to the lower case 2, the reinforcing ribs 5 correspond to the grooves of the lower case 2.

In addition to the above manufacturing method, the following manufacturing method may be used for the case body, and the manufacturing method includes the steps of:

s21, placing the shell 4 into an injection mold, wherein the shape of a cavity formed between the shell 4 and the injection mold corresponds to the shape of the lower box body 2;

s22, the raw material of the composite material is added to the cavity and injection molding is performed, so that the case 4 and the lower case 2 are directly integrated.

By the manufacturing method, the shell 4 and the lower box body 2 do not need to be bonded, and the lower part of the box body can be manufactured only by one injection molding process.

The upper box body 1 is provided with a bulge 11 which protrudes outwards, the inner space formed by the position of the bulge 11 is larger, and a battery cell or other components with larger volume can be installed.

A sealing strip 6 is arranged between the upper box body 1 and the lower box body 2, and the sealing strip 6 seals a gap between the upper box body 1 and the lower box body 2. Because the outside of lower box 2 still is provided with casing 4 in this embodiment, lower box 2 sets up on the inner wall of casing 4, and sealing strip 6 can realize the sealing connection between upper box 1, lower box 2, the casing 4 three.

As shown in fig. 10, the edge of the lower case 2 extends outward to fit on the edge of the casing 4, and the seal 6 is provided between the edge of the lower case 2 and the edge of the upper case 1. The box body is also provided with a plurality of connecting bolts 7, the connecting bolts 7 are arranged around the circumference of the sealing strip 6, and the connecting bolts 7 sequentially penetrate through the edge of the upper box body 1, the sealing strip 6, the edge of the lower box body 2 and the edge of the shell 4. Through the connecting structure, the upper box body 1, the sealing strip 6, the lower box body 2 and the shell 4 can be fixed together only by using the connecting bolt 7 without other connecting parts, and the connecting mode is simple and effective.

As shown in fig. 11, the battery box further includes a plurality of mounting bars 8, the mounting bars 8 are fixed on the outer peripheral surface of the lower case 2, since the lower case 2 is disposed on the inner wall of the housing 4 in this embodiment, the mounting bars 8 are further fixed on the outer peripheral surface of the housing 4, and the mounting bars 8 are used for mounting functional components, such as the guide mechanism 9, the lock shaft 10, the electrical connector 20, and the like. The guiding mechanism 9 is used for guiding the battery box in the replacement process, the locking shaft 10 is used for being matched with a locking mechanism fixed on the electric automobile to lock the battery box, and the electric connector 20 is used for being electrically connected with the automobile-end electric connector 20 or the station-end electric connector 20.

The electric connector 20 is disposed on an end surface of the lower case 2, and the electric connector 20 is used for electrically connecting with a vehicle-end electric connector or a station-end electric connector.

As shown in fig. 12 to 13, the guide mechanism 9 includes a guide block 91, the guide block 91 is fixed on the mounting bar 8, and the guide block 91 is used for cooperating with a guide fork on the battery replacing device to guide the position of the battery box, and the movement of the guide fork drives the battery box to move. In addition, the guide mechanism 9 further includes an elastic member 92 and a projection 93, a mounting space 94 for placing the elastic member 92 and the projection 93 is formed in the guide block 91, and the elastic member 92 applies a force to the projection 93, which force causes the projection 93 to always project outside the guide block 91 without being subjected to an external force.

When the battery box is mounted in an electric vehicle, the projection 93 receives an external pressure applied from a member adjacent to the battery box. Under the action of the elastic member 92, the projection 93 abuts against the adjacent component, so that the position of the battery box in the battery car can be relatively fixed.

As shown in fig. 14 to 15, the lock shaft 10 includes a shaft fixing portion 101 and a shaft body 102, the shaft fixing portion 101 being fixed to the mounting bar 8, and the shaft body 102 being fixed to the shaft fixing portion 101 and protruding to the side of the battery case and adapted to cooperate with the locking mechanism. The shaft body 102 can be matched with a locking mechanism of the electric automobile in the moving process of the battery box, so that the battery box and the battery automobile can be locked.

The lock shaft 10 further comprises a sensing element 103, the sensing element 103 being arranged on the shaft body 102, the sensing element 103 being adapted to sense the position of the shaft body 102 during the entry of the shaft body 102 into the lock recess of the locking mechanism. When the battery box is mounted on the battery fixing seat, the sensor on the battery fixing seat detects the signal of the sensing element 103 to judge whether the shaft body 102 is in place, so that the battery box is mounted in place.

The shaft body 102 is further provided with a shaft sleeve 104 on the outside, the shaft sleeve 104 is sleeved on the outside of the shaft body 102, the shaft sleeve 104 can rotate around the shaft body 102, and the shaft sleeve 104 can roll when contacting with other components, so that partial friction force is counteracted, and the service life of the lock shaft 10 is prolonged.

Example 2

The structure of the battery box in this embodiment is substantially the same as that of embodiment 1, except that:

as shown in fig. 16, a phase change temperature adjusting member 40 is provided inside the case, and the phase change temperature adjusting member 40 is used to adjust a temperature change in the case. The phase change temperature adjusting part 40 can absorb heat or release heat according to the temperature inside the box, when the temperature inside the box is too high, the phase change temperature adjusting part 40 absorbs heat, when the temperature inside the box is too low, the phase change temperature adjusting part 40 releases heat, thereby controlling the temperature inside the box within a proper range, and maximizing the efficiency of the battery box.

The phase change temperature adjusting parts 40 are uniformly arranged in the box body, so that all parts of the box body can receive heat absorption and release of the phase change temperature adjusting parts 40, and the temperature balance in the box body is ensured.

The phase change temperature adjusting member 40 in this embodiment is made of a phase change material or a mixture of a phase change material and an aerogel material, and the phase change material can be used as a substance for absorbing and releasing heat, is easy to obtain, and is low in manufacturing cost. Wherein, aerogel material plays fire-retardant, fire prevention and heat retaining effect, avoids battery pack to fire the burning because of the high temperature, and aerogel material's quantity can prevent the box to continue burning under the box combustion state according to the aerogel of how much quality and decide. When only the phase change temperature adjusting part 40 made of the phase change material is adopted, the flame retardant part made of the aerogel material can be additionally placed in the box body to play a role in protecting the safety of the box body.

The specific calculation formula of the mass of the phase-change material is C_{Flat plate}mΔT＝kI²Rt+m_{Phase (C)}H_{Phase (C)}Wherein, C_{Flat plate}Is the average specific heat capacity of the system [ kJ/(kg. K)]M is total system mass (kg), delta T is system change temperature (K), K is a correction parameter, I is system working current (A), R is total battery pack resistance (M omega), T is system working time (h), M is total system mass (kg), delta T is system change temperature (K), K is a correction parameter, M is total system working current (M omega), R is total battery pack resistance (M omega), T is system working time (h), and M is total system working time (h)_{Phase (C)}Mass (kg) of phase change material, H_{Phase (C)}The latent heat of phase change (kJ/kg).

The system in the embodiment mainly comprises a box body and a box bodySystem of internal battery components, system average specific heat capacity C_{Flat plate}Is selected according to the specifications of the battery pack and the case, wherein the average specific heat capacity C of the system_{Flat plate}It is the specifications of the battery assembly that play a major role; the system variation temperature delta T refers to a temperature variation range allowed by the system; the correction parameter k is designed by considering the heat calculation deviation, and is generally 1-1.2; the system working current I refers to the working current of the battery pack; the system working time t is determined according to the working current of the battery pack and the electric quantity of the battery pack, and the latent heat of phase change H_{Phase (C)}Is selected based on the joule heat (kI) generated by the system²Rt) and mass m of the phase change material_{Phase (C)}Determined by the limit of (1), latent heat of phase change H_{Phase (C)}The larger the phase change material, the lighter the weight can be used, but the more expensive the phase change material will be, so it is desirable to rationally select a phase change material having a suitable latent heat of phase change, H_{Phase (C)}Generally, 100-400kJ/kg is used.

Example 3

as shown in fig. 17, the reinforcing rib 5 is divided into two parts with the housing 4. The manufacturing method of the box body with the reinforcing ribs 5 integrally formed with the lower box body 2 and the corresponding box body comprises the following steps:

s31, placing the reinforcing rib 5 into an injection mold, wherein the shape of a cavity formed by an inner cavity of the injection mold and the reinforcing rib 5 corresponds to the shape of the lower box body 2;

and S32, adding the raw material of the composite material into the inner cavity of the injection mold, and performing injection molding to form the lower box body 2.

By the manufacturing method, the lower box body 2 and the reinforcing rib 5 are molded into a whole, and then the adhesive is coated on the inner surface of the shell 4; finally, the lower box body 2 with the reinforcing ribs 5 is placed in the shell 4, so that the outer surface of the lower box body 2 is bonded with the inner surface of the shell 4.

Example 4

as shown in fig. 18 to 19, the battery assembly of the battery case may be a plurality of individually arranged battery cells 30, and the receiving space formed by the lattice structure 21 of the inner bottom surface of the lower case 2 is matched with the shape of the individual battery cells 30. Correspondingly, the plurality of accommodating spaces of the grid structure 21 are formed by intersecting a plurality of grid bars, which are equivalent to reinforcing ribs on the lower case 2, and further enhance the strength of the lower case 2 and the entire battery box. The battery cores 30 are independently placed, so that the installation and positioning of each battery core 30 are facilitated, and the installation precision is improved; moreover, in this way, there is no need for an intermediate process of forming a module from the battery cells 30, and the assembly process is simplified; moreover, components necessary for forming a module are removed, and the weight of the battery case is relatively reduced. The grid structure 21 allows the adjacent battery cells 30 to have the same gap therebetween, and each battery cell 30 has a heat dissipation space, thereby improving the heat dissipation effect of the plurality of battery cells 30 in the battery box and ensuring the heat dissipation.

The receiving space formed by the grid structure 21 has a predetermined height, and a structural adhesive having a specific height may be filled in the receiving space, so that the battery assembly is stably fixed in the receiving space. The inner structure of the containing space is matched with the outer structure of the bottom mounting part of the battery pack, so that the battery pack can be mounted neatly, the battery pack is prevented from being mounted unstably, shaking occurs, and the overall strength of the lower box body 2 and the battery box can be further improved.

The height of the receiving space and the thickness of the lattice structure 21 should be considered in consideration of the height of the battery pack and the overall weight of the battery case. In addition, because the gaps among the plurality of battery assemblies are filled with the heat-conducting glue 3, the filling amount of the heat-conducting glue 3 affects the overall weight of the battery box, and if the height of the accommodating space is lower, the thickness of the grid structure 21 is larger, the more heat-conducting glue 3 needs to be filled, and the heavier the battery box is. Therefore, the weight of the battery case is a factor that affects the height of the receiving space and the thickness of the lattice structure 21.

Generally, the higher the height of the battery pack is, the higher the height of the receiving space is to ensure the stability of the battery pack in the receiving space. The height of the receiving space is 0.01 to 0.5 times the height of the battery pack, preferably 0.05 to 0.2 times the height of the battery pack, when designed. 1-15mm, and the accommodating space with the proper height can be selected according to the size height of the battery assembly, so that the battery assembly can be kept stable in the accommodating space. Experiments show that when the height ratio of the accommodating space to the battery pack is in the range of 0.05-0.2, the stability of the battery pack in the accommodating space and the overall strength of the battery box are optimal.

Also, the higher the height of the battery pack is, the greater the thickness of the lattice structure 21 is to ensure the supporting strength. The thickness of the grid structure 21 between two adjacent accommodating spaces is in direct proportion to the height of the battery assembly, and the thickness of the grid structure 21 is more than or equal to 1 mm. Generally, the thickness of the grid structure 21 is set to be 1-5mm, and the thickness of the grid structure 21 in this range not only can ensure that the lower case 2 and the battery case have sufficient strength as a whole, but also can ensure that a sufficient distance exists between two adjacent battery assemblies, thereby facilitating the heat dissipation of the battery assemblies. Under the intensity of battery box and battery pack's the best condition of radiating effect, can guarantee encapsulating effect and encapsulating degree of consistency (if clearance undersize between the battery pack, the colloid gets into between the battery pack when being unfavorable for the encapsulating).

In the present embodiment, since the size of the single battery cell 30 used in the battery module is 70mm × 108mm × 150mm, the height of the accommodating space is designed to be in the range of 10mm1.5 to 7554 mm. The height of the accommodation space, which ensures that the weight of the battery box is within an acceptable range, is designed to be 10mm and the thickness of the grid structure 21 is 3mm, by comprehensive consideration and calculation.

Example 5

as shown in fig. 20 to 27, the battery box further includes an outer frame 50 and a bottom guard plate 60, the reinforcing rib 5 is disposed on the lower box body 2, the outer frame 50 is sleeved on the outer peripheral surface of the lower box body 2, the outer frame 50 is fixed to the outer peripheral surface of the lower box body 2, the bottom guard plate 60 is fixed to the outer frame 50, the lower box body 2 is located in a space surrounded by the bottom guard plate 60 and the outer frame 50, and the outer bottom surface of the lower box body 2 is disposed opposite to the surface of the bottom guard plate 60.

Wherein, the foam material is filled between the outer bottom surface of the bottom protection plate 60 and the lower box body 2, the foam material has light weight, the bottom of the battery box can be filled, the problem that the strength of the lower box body 2 made of composite material is not enough is solved, the integral rigidity of the battery box is improved, and the use requirement of the battery box is met.

The reinforcing rib 5 and the lower box body 2 are integrally formed by injection molding, and the method comprises the following steps:

s41, placing the reinforcing rib 5 into an injection mold, wherein the shape of a cavity formed by an inner cavity of the injection mold and the reinforcing rib 5 corresponds to the shape of the lower box body 2;

and S42, adding the raw material of the composite material into the inner cavity of the injection mold, and performing injection molding to form the lower box body 2.

After the reinforcing rib 5 and the lower box body 2 are integrally injection-molded, the preparation method of the battery box further comprises the following steps:

s43, sleeving the outer frame 50 on the outer peripheral surface of the lower box body 2, and bonding the outer frame 50 and the outer peripheral surface of the lower box body 2 through glue;

s44, arranging the surface of the bottom protection plate 60 opposite to the outer bottom surface of the lower box body 2, fixing the bottom protection plate 60 and the outer frame 50 through bolts, arranging the lower box body 2 in a space enclosed by the bottom protection plate 60 and the outer frame 50, and filling a gap between the bottom protection plate 60 and the outer bottom surface of the lower box body 2 with a foaming material.

In addition to the above preparation method, the following preparation method comprising the steps of:

s51, placing the reinforcing ribs 5, the outer frame 50 and the bottom guard plate 60 into an injection mold, wherein the shape of a cavity formed by the inner cavity of the injection mold, the reinforcing ribs 5, the outer frame 50 and the bottom guard plate 60 corresponds to the shape of the lower box body 2;

s52, adding raw materials of composite materials into the inner cavity of the injection mold, and performing injection molding to form the lower box body 2, wherein the reinforcing ribs 5 are positioned in the lower box body 2, and the outer frame 50 and the bottom guard plate 60 are integrated with the lower box body 2.

By the above preparation method, the lower case 2, the reinforcing ribs 5, the outer frame 50 and the bottom guard plate 60 can be directly integrated into a whole without further assembly.

The outer frame 50 and the bottom guard plate 60 may be made of metal, such as aluminum, steel, etc. When the outer frame 50 and the bottom guard plate 60 are made of steel, the outer frame 50 and the bottom guard plate 60 can be formed by stamping; when the outer frame 50 and the bottom guard plate 60 are made of aluminum, the outer frame 50 and the bottom guard plate 60 can be formed by aluminum profile welding or aluminum casting.

In other embodiments, the lower case 2 made of the composite material may be used alone without providing the outer frame 50 and the bottom guard plate 60, as long as the strength requirement of the battery case is satisfied. Alternatively, the outer frame 50 may be omitted, and only the bottom cover 60 may be provided, and the surface of the bottom cover 60 may be attached and fixed to the outer bottom surface of the lower case 2. The outer frame 50 and the bottom guard plate 60 are used for compensating the problem that the lower box body 2 made of the composite material is not high in strength, so that whether the outer frame 50 and the bottom guard plate 60 need to be arranged or not can be flexibly selected according to the strength requirement of the battery box.

The mounting bar 8 may be fixed to the outer frame 50. In another embodiment, if the outer frame 50 is not provided on the outer peripheral surface of the lower casing 2, the mounting bar 8 may be directly fixed to the outer peripheral surface of the lower casing 2.

Example 6

The battery box of the present embodiment has substantially the same structure as that of embodiment 1, except that:

as shown in fig. 28, the lower case 2 in the present embodiment has a multilayer structure, the lower case 2 includes an outer case 22 and an inner case 23, the outer case 22 is used to form an outer surface of the lower case 2, the inner case 23 is used to form an inner surface of the lower case 2, and an aerogel layer 24 is pressed between the outer case 22 and the inner case 23. Multilayer structure's lower box 2 compares in single layer structure's lower box 2, and intensity is higher, and thermal insulation performance is better, and aerogel layer 24 can play better thermal-insulated effect moreover, avoids external high temperature or low temperature to the inside influence of battery box, also can further reduce by the inside heat that gives off to the external world of box, guarantees the inside temperature of box.

The aerogel layer 24 in this embodiment is made of aerogel felt, and both sides of the aerogel layer 24 may be fixed to the outer-layer case 22 and the inner-layer case 23 by adhesives, respectively. The adhesive used to secure the outer housing 22, the aerogel layer 24 and the inner housing 23 is well known in the art and will not be described in detail herein. After the three is connected fixedly, can further compress tightly the three through the compression technology, improve the fastness that the three is connected, guarantee the stability of box 2 down.

In other alternative embodiments, the aerogel layer 24 may be made of aerogel material of other structures, such as liquid aerogel filled between the outer box 22 and the inner box 23, and after the filling is completed, the aerogel is cured and compressed against the outer box 22, the aerogel layer 24 and the inner box 23.

When adopting lower box 2 in this embodiment, can not set up the heat preservation down in addition, save the time of installation heat preservation down, improve the installation effectiveness. If the requirement for the thermal insulation performance of the battery box is higher, a lower thermal insulation layer can be arranged on the outer surface of the outer box body 22, namely the outer surface of the lower box body 2.

Since the battery module is mounted and fixed on the lower case 2, in order to enable the lower case 2 to stably support the battery module, a metal shell 4 may be further disposed outside the lower case 2, and the lower case 2 may be disposed inside the metal shell 4, so as to reinforce the strength of the lower case 2.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like are used in the orientations and positional relationships indicated in the drawings, which are based on the orientations and positional relationships indicated in the drawings, and are used for convenience of description and simplicity of description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be construed as limiting the present invention unless otherwise specified herein.

While specific embodiments of the utility model have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the utility model is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the utility model, and these changes and modifications are within the scope of the utility model.

Claims

1. The battery box is characterized by comprising a box body and a battery assembly arranged in the box body, wherein the box body comprises a lower box body made of a composite material, the composite material is one of SMC (sheet molding compound) composite material, PCM (pulse code modulation) composite material and carbon fiber material, and heat-conducting glue is filled in the inner space of the box body.

2. The battery box according to claim 1, wherein a phase change temperature adjusting member is further provided inside the box body, the periphery of the phase change temperature adjusting member is filled with the heat conductive adhesive, and the phase change temperature adjusting member is used for adjusting temperature change inside the box body.

3. The battery box according to claim 2, wherein the phase change temperature adjusting member is uniformly disposed inside the box body.

4. The battery box of claim 3, wherein the material of the phase change temperature adjusting member is a phase change material.

5. The battery box according to any one of claims 1 to 4, characterized in that the box body further comprises a reinforcing rib provided on the lower box body and injection-molded integrally with the lower box body.

6. The battery box according to any one of claims 1 to 4, wherein the box body further comprises a case, and the lower box body is provided on an inner wall of the case.

7. The battery box according to any one of claims 1 to 4, wherein the lower box body comprises an outer box body and an inner box body, and an aerogel layer is crimped between the outer box body and the inner box body.

8. The battery box according to any one of claims 1 to 4, further comprising at least one mounting bar fixed to an outer circumferential surface of the lower box body, the mounting bar being used to mount at least one functional member; the functional part is one of a guide mechanism, a lock shaft and an electric connector, the guide mechanism is used for guiding the battery box in the replacement process, the lock shaft is used for being matched with a locking mechanism fixed on the electric vehicle to lock the battery box, and the electric connector is used for being electrically connected with a vehicle-end electric connector or a station-end electric connector.

9. The battery box according to any one of claims 1-4, characterized in that the battery box further comprises a heat exchange pipeline, the heat exchange pipeline is installed in the box body and is arranged corresponding to the battery assembly, and the heat exchange pipeline is used for circulating fluid to realize heat exchange with the battery assembly.