JP2019129077A - Secondary battery module - Google Patents

Abstract

To efficiently suppress temperature rise of a secondary battery module and an electronic component.SOLUTION: With respect to a secondary battery module having a secondary battery, a substrate, an electronic component provided on the substrate, and a housing for housing the secondary battery, the substrate, and the electronic component, the second battery module has a secondary battery heat dissipation part exposed to the outside of the secondary battery module by thermally making contact with the secondary battery, and an electronic component heat dissipation part exposed to the outside of the secondary battery module by thermally making contact with the electronic component, and the secondary battery heat dissipation part and the electronic component heat dissipation part are partitioned by a stationary member having thermal conductivity lower than that of the electronic component heat dissipation part.SELECTED DRAWING: Figure 1

Description

The present invention relates to a secondary battery module.

  In recent years, demand for in-vehicle secondary batteries is increasing against the background of environmental regulations. Among these, lithium ion secondary batteries are generally considered promising because they can be miniaturized and have high energy density because they have higher discharge potential than lead batteries and nickel hydrogen batteries. Furthermore, as the power used in the vehicle, there are a high voltage circuit mainly driving a motor etc. and a low voltage circuit driving electrical components such as headlights and turn signals, so the voltage obtained from the secondary battery is It is converted into an arbitrary voltage and supplied by a DC / DC converter. Generally, the secondary battery and the DC / DC converter are mounted on the vehicle as independent electrical components, but in order to realize further efficiency improvement and miniaturization, the secondary battery and the DC / DC converter are integrated, and There is a need for a secondary battery module that outputs a voltage.

  However, since the temperature of the secondary battery and the DC / DC converter rise due to Joule heat, there is a possibility that the temperature rise of the integrated secondary battery module is further increased due to the respective heat generation. In particular, in the case of a lithium ion secondary battery, when the temperature continues to be high, the deterioration of the battery is accelerated and the characteristics are degraded. For this reason, there is a need for a technique for preventing the heat generated by the DC / DC converter from affecting the temperature rise of the battery. With respect to these problems, for example, a structure for efficiently removing the heat generated by the battery and the electronic component has been studied.

  For example, Patent Document 1 discloses a technology in which first and second cooling fans are provided to cool one or the other of the battery group and the electric / electronic unit, respectively.

  Further, Patent Document 2 discloses a technology related to a battery module provided with a heat sink interposed between a battery case and a heat sink and having a larger area of the sandwiching part with the battery case than the area of the sandwiching part with the heat sink Is disclosed.

JP 2006-24510 A

JP 2004-79219 A

  However, in the case where the cooling fan is provided in the battery module as in Patent Document 1, the structure becomes large, and since the vent is required, the battery module can not be sealed.

  Further, in the structure of Patent Document 2, although the heat of the electronic component is dissipated to a certain extent through the heat sink, the heat may be transmitted to the secondary battery through the inside of the battery module to raise the temperature of the secondary battery. There is.

  An object of the present invention is to provide a structure of a battery module capable of suppressing heat transfer from an electronic component to a secondary battery while suppressing an increase in size of the battery module as much as possible.

  An example of means for solving the above problems is as follows.

  In a secondary battery module having a secondary battery, a substrate, an electronic component provided on the substrate, and a housing for accommodating the secondary battery, the substrate and the electronic component, the secondary battery module is: A secondary battery heat dissipating part that is in thermal contact with the secondary battery and exposed to the outside of the secondary battery module, and an electron that is in thermal contact with the electronic component and exposed to the outside of the secondary battery module. A secondary battery module having a component heat radiation part, wherein the secondary battery heat radiation part and the electronic component heat radiation part are separated by a fixing member having a lower thermal conductivity than the secondary battery heat radiation part and the electronic component heat radiation part .

  ADVANTAGE OF THE INVENTION By this invention, the structure of the battery module which suppressed the heat transfer from an electronic component to a secondary battery can be provided, suppressing the enlargement of a battery module as much as possible.

Sectional perspective view of a secondary battery module according to a first embodiment of the present invention Cross-sectional view for explaining the first embodiment Sectional drawing explaining Example 2 Sectional drawing explaining Example 3 Sectional drawing explaining Example 4 Sectional drawing explaining Example 5 Sectional drawing explaining Example 6

  Examples of modes for carrying out the invention will be described below by way of examples.

Example 1
FIG. 1 is a cross-sectional perspective view of a secondary battery module according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of the AA 'cross section of FIG.

  The secondary battery module 1 houses a battery group 11 in which a plurality of prismatic batteries 5 are stacked, a DC / DC converter 6, a support member 8 that supports the DC / DC converter 6, and a DC / DC converter 6. Housing 4, first housing 2 for housing them, and housing lid 3 for sealing the first housing.

  The first housing 2 has a surface in contact with the prismatic battery 5 and a surface on the opposite side where the DC / DC converter 6 is provided.

  The battery group 11 is formed, for example, by stacking rectangular batteries 5 such as lithium ion secondary batteries having wide surfaces and narrow surfaces with the wide surfaces facing each other. The battery group 11 has the rectangular batteries 5 stacked, and is disposed so as to be pressed against the side surface of the first housing 2 by the securing member 7 and to be in contact with the first case 2. The prismatic battery 5 has a positive electrode terminal 15 and a negative electrode terminal 16, and the prismatic battery has a narrow width on which these are provided and a bottom surface which is a narrow surface opposite to this surface, Are accommodated in the secondary battery module 1 in a state of being in contact with the first housing 2. The heat generated by the rectangular battery 5 is transmitted from the bottom to the first case. Since the first housing 2 is exposed to the outside of the secondary battery module 1, heat is dissipated to the outside of the secondary battery module from here. In this structure, the first housing functions as a secondary battery heat sink. The prismatic secondary battery 5 and the first housing 2 may be in direct contact or may be in thermal contact with each other. Here, the state of being in thermal contact is a state of being directly or indirectly connected without the use of a heat insulating material such as a resin material or a rubber material.

  The secondary battery module 1 has a control substrate for controlling the battery group 11, a wire, a relay, and a fuse, which are provided on the support member 8.

  The support member 8 is, for example, a plate-like member, and is located between the DC / DC converter 6 and the battery group 11 at the central portion of the first housing. The support member 8 is fixed to the first housing 2 by, for example, a bolt. Further, the support member 8 has a surface on the battery group 11 side and a surface on the DC / DC converter 6 side. A control substrate for controlling the battery group 11, wiring, a relay, and a fuse are provided on the surface on the battery group 11 side.

  A DC / DC converter 6 is provided on the surface of the first housing 2 opposite to the surface with which the square battery 5 is in contact.

  The DC / DC converter 6 has a configuration in which an electronic component 6b such as a coil, a capacitor, or a semiconductor is disposed on a substrate 6a. The DC / DC converter 6 is accommodated in the second housing 4, and the substrate 6 a and the electronic component 6 b are in thermal contact with the second housing. The first housing 2 has an opening 10 in the surface opposite to the surface in contact with the prismatic battery 5. The second housing 4 has a convex shape, and the convex exposed portion 4 a is exposed to the outside of the first housing 2 from the opening 10. The exposed portion 4a has a height substantially flush with the surface of the first housing 2 and is exposed to the ambient air.

  As described above, since the second casing 4 is exposed to the outside of the secondary battery module 1 by the exposed portion 4a, the heat generated in the electronic component 6b included in the DC / DC converter 6 is generated from here. Is dissipated outside. In this structure, the second housing functions as an electronic component heat sink. The electronic component 6b and the second housing 4 may be in direct contact or may be in thermal contact with each other. Here, the state of being in thermal contact is a state of being directly or indirectly connected without the use of a heat insulating material such as a resin material or a rubber material. Here, in order to bring the electronic component 6 b into close contact with the second housing 4, a sheet or grease having a high thermal conductivity is disposed between the electronic component 6 b and the second housing 4 to reduce the thermal resistance of the heat radiation path. The structure may be

  The substrate 6 a of the DC / DC converter 6 and the second housing 4 are fixed to the surface of the support member 8 opposite to the battery group 11. The second housing 4 is fixed to the support member 8 by, for example, a bolt.

  The second housing 4 and the first housing 2 are fixed and connected via a fixing member 9 made of a material having a thermal conductivity lower than that of the second housing 4 and the first housing 2 Yes. The fixing member 9 is a material having a thermal conductivity lower than that of the material constituting the second housing 4 and the first housing 2, that is, a heat insulating material, and is a material having flexibility. It is more desirable to have. For example, resin materials and rubber materials can be used. By pressing the second housing 4 to the first housing 2 by the fixing member 9, the fixing member 9 is in close contact with the second housing 4 and the first housing 2 so that waterproofness and dust resistance can be achieved. It can be set as the secondary battery module 1 which has. In addition, since the fixing member 9 has thermal insulation, the portion exposed to the outside of the secondary battery module of the first case 2 where the square battery 5 is in thermal contact (secondary battery heat sink) and the electronic component 6a Of the second housing 4 in thermal contact, the exposed portion 4a (the electronic component heat sink) exposed to the outside of the secondary battery module is thermally blocked, so that one of the temperatures is lower to higher. It is possible to prevent the heat transfer to the person.

The effects of the present embodiment described above are summarized below.
(1) Suppression of Temperature Rise of DC / DC Converter Heat generated from the substrate 6a and the electronic component 6b constituting the DC / DC converter 6 is transmitted to the second housing 4 and the exposed portion 4a of the second housing 4 The heat is dissipated to the ambient air. Since the second housing 4 acts as an electronic component heat dissipation portion, heat can be dissipated directly from the surface 4a of the second housing 4 to which the electronic component 6b is thermally connected in this manner, and the temperatures of the substrate 6a and the electronic component 6b The rise can be efficiently suppressed.
(2) Suppression of Temperature Rise of Rectangular Battery 5 Heat generated by the rectangular battery 5 is transmitted to the first housing 2 and dissipated from the surface 2 a of the first housing 2 to the ambient air. The first housing 2 acts as a heat sink for the secondary battery, and the heat generated by the rectangular battery 5 can be dissipated to the outside of the secondary battery module 1.
(3) Suppression of heat transfer between the electronic component heat radiating portion and the secondary battery heat radiating portion The second housing 4 and the first housing 2 are in contact via the fixing member 9 having a low heat conductivity Therefore, the movement of heat is less likely to occur in the second housing 4 thermally connected to the electronic component 6 b and the first housing 2 thermally connected to the battery portion 11, and the heat generation of the DC / DC converter 6 Can be transmitted to the rectangular battery 5 to suppress an increase in battery temperature.

  Generally, in the lithium ion secondary battery and the DC / DC converter, the DC / DC converter generates more heat. Therefore, when the DC / DC converter 6 is provided in contact with the square battery 5, When the DC / DC converter 6 is in thermal contact with the prismatic battery 5 via the casing 2 and the first casing 4 and the DC / DC converter 6 is in contact, heat generated by the DC / DC converter 6 is transferred to the prismatic battery 5; This causes the temperature of the prismatic battery 5 to rise. In the case of directly connecting the second housing 4 in thermal contact with the DC / DC converter 6 to release heat to the outside and the first housing 2 in thermal contact to the square battery 5 to release heat to the outside Instead, the heat transfer from the DC / DC converter 6 to the prismatic battery 5 is prevented while maintaining the waterproof and dustproof properties of the secondary battery module 1 by bringing the secondary battery module 1 into contact through the fixing material 9 having low thermal conductivity. Each temperature rise can be suppressed. Thereby, an excessive temperature rise of the electronic component 6b can be suppressed while suppressing the deterioration of the battery performance, so that the highly reliable secondary battery module 1 can be supplied.

  Further, in the first housing 2, since the surface on which the battery group 11 contacts and the surface on which the opening 10 is provided are different surfaces, it is possible to earn a distance, thereby preventing further movement of heat. can do. Preferably, as shown in FIGS. 1 and 2, a surface of the first casing 2 facing each other is provided with a surface in contact with the battery group 11 and the opening 10.

  In the present embodiment, an example was shown in which two sets of battery groups 11 in which 12 prismatic batteries 5 were stacked in the first casing 2 were arranged, but the number of stacked and arranged sets of the square batteries 5 is limited. It is not something.

  Further, in order to suppress the temperature rise of prismatic battery 5 and DC / DC converter 6, for example, a heat sink is fixed to surface 4a of second housing 4 and exposed surface 4a of first housing 2. Therefore, the temperature rise of the square battery 5 and the DC / DC converter 6 can be efficiently suppressed. However, the cooling structure is not limited to the heat sink, and an air cooling structure with a fan attached or a water cooling structure may be fixed.

(Example 2)
The present embodiment is an example using a structure in which a fin shape 4 b for enlarging the surface area is provided on the second housing surface 4 a for housing the DC / DC converter 6. The structure other than the fin shape 4 b is the same as that of the first embodiment.

  FIG. 3 is a cross-sectional view of the secondary battery module 1 of the second embodiment.

  The 2nd housing | casing 4 has the fin-shaped part 4b which expands a surface area. The fin-shaped portion 4 b is provided in the exposed portion 4 a and is exposed to the outside of the secondary battery module 1 from the opening 10. The fin-shaped portion 4b has, for example, a shape in which a plurality of plate-shaped portions are arranged, but other known fin shapes having a high surface area can also be used. The fin shape 4 b is desirably formed integrally with the second housing 4, but the fin shape 4 b may be a separate structure and fixed to the second housing 4 with a bolt or the like. The second housing 4 and the fin shape 4 b desirably have high thermal conductivity, and may be formed of, for example, a metal material such as aluminum or copper. The second housing 4 is pressed against the inner wall surface of the first housing 2 via the fixing member 9 as in the first embodiment.

  According to the present embodiment described above, the heat generated in the DC / DC converter 6 is transmitted to the second casing 4 and efficiently radiated from the fin shape 4b to the ambient air.

(Example 3)
The third embodiment has a structure in which the substrate 6a forming the DC / DC converter 6 is divided, and the second case 4 covering the first circuit 13 and the third case 12 covering the second circuit 14 are provided. An example of The other structure is the same as that of the first embodiment.

  FIG. 4 is a cross-sectional view of the secondary battery module 1 of the third embodiment.

  The DC / DC converter 6 includes a first circuit 13 and a second circuit 14 having different temperature upper limits. The first circuit 13 and the second circuit 14 are respectively provided on a substrate, and the substrate is provided separately for the first circuit board 13a and the second circuit board 14a. As a circuit having a low heat resistance and a low temperature upper limit, for example, a circuit provided with a capacitor can be mentioned. Moreover, as a circuit whose temperature upper limit is high compared with this, a coil and a semiconductor element are raised. Therefore, for example, a circuit in which a coil or a semiconductor element is provided in the first circuit 13 and a circuit in which a capacitor is provided in the second circuit 14 can be used.

  The first circuit 13 is covered by a second case 4, and the second circuit 14 is covered by a third case 12. The first circuit 13 and the third circuit 14 are respectively exposed from the opening provided in the first case 2 through the exposed portion (exposed portion) 4a of the second case and the exposed portion of the third case (third The second exposed portion is exposed as 12a. The exposed portion 4 a and the exposed portion 12 a are separated by the first housing 2 and the fixing member 9.

  The first circuit 13 having an element with a high temperature upper limit and the second circuit 14 having an element with a low upper temperature limit are separated, and the respective circuits are housed in different cases 4 and 12 and separated by a fixing member 9. By separating the heat dissipation path, the heat transfer from one to the other can be prevented. In addition, a cooling structure can be constructed in accordance with the upper temperature limit of the element. For example, the second casing 4 covering a circuit with a low upper temperature limit is constructed so that the area of the heat dissipation surface 4a is large, and the surface 12a of the third casing 12 covering the circuit 14 with a high upper temperature limit keeps the area small Thus, it is possible to realize a cooling structure that matches the upper temperature limit of the electronic component 6b.

(Example 4)
The fourth embodiment is an example of a structure in which a convex portion 8 a is provided on a support member 8 for holding a substrate 6 a forming the DC / DC converter 6 and the second housing 4 is in contact. The other structure is the same as that of the first embodiment.

  FIG. 5 is a cross-sectional view of the secondary battery module 1 of the fourth embodiment.

  The support member 8 has a convex portion 8 a, and the convex portion 8 a is in contact with the second housing 4. The internal space of the first housing 2 is separated from the space in which the battery group 11 is disposed and the space in which the DC / DC converter 6 is disposed by the support member 8 and the convex portion 8a. Thus, thermal interference between the battery group 11 and the DC / DC converter 6 through the fluid in the first housing 2 can be suppressed. Furthermore, when an abnormality occurs in any one of the rectangular batteries 5 of the battery group 11 and the gas and the internal electrolyte contained in the rectangular battery 5 are ejected, the DC / DC converter 6 performs the battery group 11. And the second housing 4 are disposed in a space different from that in the second embodiment, so that the contamination of the substrate 6a by the electrolytic solution can be prevented.

  In the present embodiment, the internal space of the first housing 2 is separated by providing the convex portion 8 a in the support member 8, but the convex portion 8 a may not be integral with the support member 8. Another member having substantially the same shape as the gap between the one casing 2 and the casing lid 3 may be fixed and brought into close contact with the first casing 2 and the casing lid 3.

(Example 5)
The fifth embodiment is an example of a structure in which the substrate 6 a forming the DC / DC converter 6 is fixed to the second housing 4 and the second housing 4 is fixed to the first housing 2. The other structure not specified is the same as in Example 1.

  FIG. 6 is a cross-sectional view of the secondary battery module 1 of the fifth embodiment.

  The DC / DC converter 6 is fixed and accommodated in the second housing 4. As in the first embodiment, the second housing 4 has an exposed portion 4 a exposed from the opening 10 provided in the first housing. The second case 4 has a first case bottom 15 on the surface opposite to the exposed portion 4 a, and the substrate 6 a forming the DC / DC converter 6 is provided on the case bottom 15. .

  The electronic component 6 a mounted on the DC / DC converter 6 is in contact with the exposed portion 4 a side of the second housing 4. In addition, a fixing member 9 is provided on the contact surface between the second housing 4 and the first housing 2, and the second housing 4 is fixed to the first housing 2 by bolts and held. It has become.

  According to the embodiment described above, the heat generated by the DC / DC converter 6 is transmitted to the second housing 4 and dissipated from the surface 4a. In this structure, since the DC / DC converter 6 is held by the first housing 2, the support member 8 does not have to support the DC / DC converter 6 and is miniaturized so as to hold other electric components. Thus, the volume increase of the secondary battery module 1 can be suppressed.

(Example 6)
In the sixth embodiment, in the first case 2 for storing the battery group 11, the opening 10 is provided on the case bottom 2a which is a surface facing the case lid 3 and the second for storing the DC / DC converter 6 The case 4 is an example of a structure in which the case 4 is exposed to the bottom side of the first case 2.

  FIG. 7 is a cross-sectional view of the secondary battery module 1 of the sixth embodiment.

  The DC / DC converter 6 is fixed and accommodated in the second housing 4. As in the first embodiment, the second housing 4 has an exposed portion 4 a exposed from the opening 10 provided in the first housing. The second case 4 has the first case bottom 15 on the opposite side of the exposed portion 4a as in the sixth embodiment, and the substrate 6a forming the DC / DC converter 6 is a case. It is provided at the bottom 15.

  The opening 10 is provided on the first housing bottom 2 a side which is the surface of the first housing 2 opposite to the housing lid 3. Further, in the first housing 2, the surface in contact with the rectangular battery 5 is also the first housing bottom surface 2 a, and the surface in which the opening 10 is provided and the surface in contact with the rectangular battery 5 are the first The housing 2 is provided on the same surface. The exposed portion 4 a of the second housing 4 is provided to have substantially the same height as the bottom surface 2 a of the first housing 2, and the exposed portions of the first housing bottom surface 2 a and the second housing 4 4 a is thermally separated by a fixing member 9.

  According to the present embodiment described above, the surface of the second casing 4 that is the heat dissipation path of the battery group 11 and the heat dissipation path of the DC / DC converter 6 in the first casing 2 that is the heat dissipation path of the battery group 11. By forming 4a on the same surface, the thermal interference caused by the first casing 2 of the prismatic battery 5 and the DC / DC converter 6 is suppressed, and the second casing 4 and the second casing 4 One casing 2 can be cooled, and the temperature rise of the square battery 5 and the DC / DC converter 6 can be suppressed.

  As a cooling structure, for example, by arranging a water cooling jacket on the bottom surface of the battery module 1, the plurality of rectangular batteries 5 and the DC / DC converter 6 can be cooled. However, the cooling structure is not limited to the water cooling, and may be a cooling structure by a ventilation path or a fin structure.

DESCRIPTION OF SYMBOLS 1 ... Secondary battery module, 2 ... 1st housing | casing (housing | casing), 2a ... 1st housing | casing bottom face, 3 ... housing | casing lid, 4 ... 2nd housing | casing, 4a ... 2nd housing | casing Exposed part (exposed part), 4b: fin shape, 5: square battery (secondary battery), 6: DC / DC converter, 6a: substrate, 6b: electronic component, 7: securing member, 8: supporting member, 8a: support member convex portion, 9: fixing member, 10: opening portion, 11: battery group, 12: third case, 12a: exposed portion of the third case (second exposed portion), 13: First circuit, 13a: first circuit board, 13b: electronic component, 14: second circuit, 14a: second circuit board, 14b: electronic component, 15: first case bottom

Claims (12)

With a secondary battery,
A substrate, and an electronic component provided on the substrate;
In a secondary battery module having a housing for accommodating the secondary battery, the substrate, and the electronic component,
The secondary battery module is in thermal contact with the secondary battery, and the secondary battery heat dissipation portion exposed to the outside of the secondary battery module and the electronic component in thermal contact with the electronic component It has an electronic component heat dissipation part exposed to the outside of the module,
The secondary battery module in which the secondary battery heat sink and the electronic component heat sink are separated by a fixing member having a thermal conductivity lower than that of the secondary battery heat sink and the electronic component heat sink. In claim 1,
The secondary battery is in thermal contact with the secondary battery,
The secondary battery module has a second housing that contacts the electronic component and accommodates the electronic component.
The secondary battery heat sink is a portion of the housing exposed to the outside of the secondary battery module,
The said electronic component heat sink is a secondary battery module which is a part exposed outside the said secondary battery module among the said 2nd housing | casings. In claim 2,
The second housing is housed in the housing;
The housing has an opening;
The said 2nd housing | casing has an exposed part exposed to the exterior of the said secondary battery module from the said opening part, The secondary battery module whose said exposed part is the said electronic component heat sink. In claim 3,
The said electronic component is a semiconductor, or a secondary battery module which is either a coil or a capacitor. In claim 4,
The said electronic component is a secondary battery module which is a component which forms a DC / DC converter. In claim 5,
The secondary battery module in which the support member in which the said board | substrate was provided was provided in the inside of the said housing | casing. In claim 6,
The said supporting member is located between the said secondary battery and DC / DC converter, and the secondary battery module connected with the said housing | casing. In claim 7,
There is a space provided with the secondary battery and a space provided with the DC / DC converter in the housing, a space provided with the secondary battery, and a space provided with the DC / DC converter Is a secondary battery module separated by the support member. In claim 7 or claim 8,
The secondary battery module, wherein the surface of the housing to which the secondary battery is thermally connected and the surface provided with the opening are different surfaces. In claim 9,
The fixing member is a secondary battery module that is at least one of a resin material and a rubber material. In claim 10,
The secondary battery module provided with the circuit which controls the said secondary battery in the surface at the side of the said secondary battery of the said supporting member. In claim 11,
The said exposed part is a secondary battery module which has a fin shape on the said secondary battery module outer side.

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