JP2011014321A - Battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve safety by preventing certainly gas leakage.SOLUTION: The battery system includes: a battery block 2 in which a plurality of square battery cells 1A are laminated in a posture to arrange the gas exhaust port 12 of the gas export valve 11 on an identical plane; an exhaust duct 20 of a hollow shape, which is arranged opposed to the gas exhaust port 12 of each square battery cell 1A constituting this battery block 2 and exhausts gas discharged from the gas exhaust port 12 to the outside; and an outer package case 30 which houses the battery block 2 in which the exhaust duct 20 is arranged. In the battery system, the outer package case 30 is arranged at a constant position by pushing elastically the exhaust duct 20 to the battery block 2.

Description

  The present invention mainly relates to a battery system used in a power supply device for a vehicle that supplies electric power to a motor that drives a hybrid car, an electric vehicle, and the like, and in particular, discharges a gas discharged from a gas discharge valve of a battery cell. It is related with the battery system discharged outside.

  A battery system including a large number of battery cells can be connected to battery cells in series to increase the output voltage, and thus is used for applications that are charged and discharged with a large current, such as a power supply device of a hybrid car. This battery system is discharged with a very large current when accelerating the vehicle, and is charged with a considerably large current in a state such as regenerative braking. In this battery system, a gas discharge valve is provided in the battery cell in order to prevent destruction in an abnormal state in which the internal pressure increases due to overcharge or overdischarge and to ensure safety. The gas discharge valve opens and exhausts gas when the internal pressure of the battery rises abnormally. In a battery system including a large number of battery cells, it is important to quickly exhaust the gas discharged from the battery cells to the outside. In particular, in a rectangular battery cell using a non-aqueous electrolyte solution such as a lithium ion battery, it is important to exhaust the exhaust gas promptly. In order to realize this, a battery system in which an exhaust tube is connected to an exhaust port of a gas exhaust valve of a battery cell has been developed. (See Patent Document 1)

JP 2007-157633 A

  The battery system of the cited document 1 has connected the exhaust tube to the gas discharge port of the square battery. In this battery system, the exhaust gas of the rectangular battery is exhausted to the outside through an exhaust tube. In this battery system, a large number of rectangular battery cells are stacked, and both end surfaces thereof are sandwiched between end plates to form a battery block. In this battery block, an exhaust tube is arranged on the upper surface, and the gas discharge port of each rectangular battery cell is connected to the exhaust tube. The exhaust tube is disposed at a fixed position of the battery block with both ends fixed to the battery block end plate.

  In the battery system having this structure, it is difficult to connect the exhaust tube and the gas discharge port of each rectangular battery cell so as not to leak gas. In the rectangular battery cell, when the internal pressure of the battery becomes abnormally high, the gas discharge valve opens and high temperature and high pressure gas is ejected from the gas discharge port. High-temperature and high-pressure gas ejected vigorously from the gas discharge port deforms the exhaust tube. In particular, the exhaust tube having both ends fixed to the end plate is likely to be deformed by high-temperature and high-pressure gas ejected vigorously from the central rectangular battery cell. When the exhaust tube is deformed, a gap is formed between the exhaust tube and the rectangular battery cell, which causes gas leakage. The gas leaking from the gap causes various harmful effects on the battery system. In particular, in a battery system using a non-aqueous electrolyte prismatic battery cell such as a lithium ion battery, the leaked gas is ignitable and the safety is significantly reduced.

  As a battery system that solves this drawback, the present inventor arranges a discharge duct 94 between the battery block 92 and the outer case 93 as shown in the sectional view of FIG. Developed a structure to be fixed to. In this battery system, since the discharge duct 94 is fixed to the strong outer case 93, deformation of the discharge duct 94 can be prevented even in a state where high-temperature and high-pressure gas is exhausted. However, the battery system of this structure also has a drawback that it is difficult to always prevent gas leakage. This is because the battery block 92 and the outer case 93 have different dimensions for expansion and contraction depending on the temperature, and the relative position between the discharge duct 94 and the gas discharge port 95 is shifted due to the dimensional error of the rectangular battery cell 91 and the outer case 93. .

The present invention has been developed for the purpose of solving this drawback, and an important object of the present invention is to provide a battery system that can reliably prevent gas leakage and improve safety.
In particular, the battery system of the present invention has an error in the dimensional accuracy of the battery block, the outer case, and the gas discharge duct, and the dimensions in which these expand and contract depending on the temperature are different. An object of the present invention is to provide a battery system that can effectively prevent gas leakage.

Means and effects for solving the problems

  The battery system of the present invention includes a battery block 2 in which a plurality of prismatic battery cells 1A are stacked in a posture in which the gas discharge ports 12 of the gas discharge valve 11 are arranged on the same surface, and each of the squares constituting the battery block 2. A battery block 2 formed by disposing a hollow discharge duct 20 disposed opposite to the gas discharge port 12 of the battery cell 1 </ b> A and exhausting the gas discharged from the gas discharge port 12 to the outside, and the discharge duct 20. And an outer case 30 that houses the container. In the battery system, the outer case 30 is disposed in a fixed position by elastically pressing the discharge duct 20 against the battery block 2.

  The battery system described above has a feature that gas leakage can be reliably prevented and safety can be improved. In particular, the battery system described above has errors in the dimensional accuracy of the battery block, the outer case, and the gas exhaust duct, and the dimensions in which they expand and contract depending on the temperature are different. There is a feature that gas leakage can be effectively prevented. This is because the battery system described above is arranged at a fixed position of the battery block by elastically pressing the discharge duct against the battery block with the outer case. The discharge duct is pressed against the surface of the battery block by the elasticity of the exterior case or the discharge duct, or is pressed against the surface of the battery block by providing an elastic body. In this structure, since the discharge duct is elastically pressed against the surface of the battery block, a dimensional error or distortion occurs, or even if the relative position between the discharge duct and the prismatic battery cell shifts, It is elastically pressed against the surface and no gas leak gap is generated. Furthermore, even in an environment where the battery system is subjected to vibration or impact like a vehicle, there is a feature that can effectively prevent a gas leakage gap from being elastically pressed against the surface of the rectangular battery cell.

In the battery system of the present invention, an elastic pressing member 21 that elastically presses the discharge duct 20 against the surface of the battery block 2 can be disposed between the outer case 30 and the discharge duct 20.
This battery system can increase the amount of elastic deformation by which the discharge duct is elastically pressed against the surface of the battery block, that is, the dimension capable of elastic deformation, by the elastic pressing material. For this reason, the shift | offset | difference of the relative position of the discharge duct and a square battery cell by a dimensional error or distortion can be absorbed efficiently, and gas leak can be prevented more effectively.

In the battery system of the present invention, a packing 22 that is elastically deformed can be disposed between the discharge duct 20 and the battery block 2.
This battery system can efficiently absorb the displacement of the relative position between the discharge duct and the battery block by elastic deformation of the packing, and can more reliably prevent gas leakage.

In the battery system of the present invention, the elastic coefficient of the packing 22 is made larger than the elastic coefficient of the elastic pressing member 21, and the elastic displacement of the packing 22 is changed from the elastic displacement of the elastic pressing member 21 in a state where the packing 22 is pressed. Can also be increased.
In this battery system, since the elastic displacement of the packing is larger than the elastic displacement of the elastic pressing member, the discharge duct is connected to the gas discharge port of the rectangular battery cell in a state in which the packing is largely elastically deformed. For this reason, even if the relative position of the discharge duct and the rectangular battery cell is greatly deviated, the misalignment is absorbed by the packing, and gas leakage can be prevented in an ideal state.

In the battery system of the present invention, the packing 22 includes a fitting groove 22 </ b> C of the discharge duct 20 on a surface facing the discharge duct 20, and the discharge duct 20 includes a ridge 25 guided by the fitting groove 22 </ b> C. The ridge 25 can be guided to the fitting groove 22C, and the packing 22 and the discharge duct 20 can be connected to a fixed position.
Since this battery system inserts the convex line of the discharge duct into the fitting groove of the packing, there is a feature that gas leakage between the discharge duct and the packing can be reliably prevented.

In the battery system of the present invention, the packing 22 is provided with through holes 22A at positions opposite to the gas discharge ports 12 of the respective square battery cells 1A, and the rectangular battery cells 1A are stacked between the through holes 22A. A boundary closing portion 22B that closes the stacking gap 17 formed at the boundary can be provided.
This battery system has a feature that can reliably prevent gas from leaking to the boundary of the rectangular battery cell by packing.

In the battery system of the present invention, the packing 22 can be a plastic foam having closed cells.
This battery system can be sandwiched between the discharge duct and the battery block to increase the amount of elastic deformation of the packing. For this reason, the packing has a feature that can reliably prevent gas leakage between the discharge duct and the rectangular battery cell.

In the battery system of the present invention, the battery block 2 has the insulating separator 15 disposed between the rectangular battery cells 1A, and the insulating separator 15 has a protruding portion 15B protruding from the outer periphery of the battery block 2, and this protrusion The portions 15B are provided on both sides of the discharge duct, so that the discharge duct 20 can be arranged at a fixed position with the protruding portions 15B.
In this battery system, the battery block and the gas discharge duct are prevented from being displaced, and the discharge duct can be arranged at an accurate position of the battery block.

In the battery system of the present invention, the protruding portion 15B of the insulating separator 15 can be used as the cover portion 17 of the electrode terminal 13 of the rectangular battery cell 1A.
In this battery system, the discharge duct is placed at a fixed position using the cover of the electrode terminal, so there is no need to provide a dedicated member for placing the discharge duct at the fixed position. The duct can be placed in place.

It is sectional drawing of the battery system which this inventor developed previously. 1 is a perspective view of a battery system according to an embodiment of the present invention. It is the III-III sectional view taken on the line of the battery system shown in FIG. FIG. 3 is a perspective view in which an upper case of the battery system shown in FIG. 2 is removed. FIG. 3 is a perspective view in which an outer case of the battery system shown in FIG. 2 is removed. FIG. 6 is an exploded perspective view of the battery system shown in FIG. 5. It is a side view of the battery system shown in FIG. FIG. 4 is an enlarged vertical vertical sectional view of a main part of the battery system shown in FIG. 2, corresponding to a cross section taken along line VIII-VIII in FIG. 2. It is a perspective view of the discharge duct shown in FIG. FIG. 10 is a partially enlarged exploded perspective view of the discharge duct shown in FIG. 9. It is an expansion cross-sectional view of a discharge duct. It is an expansion perspective view which shows the connection structure of a discharge duct and a battery block. It is a disassembled perspective view which shows the connection structure of the discharge duct and battery block shown in FIG. It is an expansion perspective view which shows the connection structure of a connection duct and a battery block. It is a disassembled perspective view which shows the connection structure of the discharge duct and battery block shown in FIG.

  Embodiments of the present invention will be described below with reference to the drawings. However, the embodiment described below exemplifies a battery system for embodying the technical idea of the present invention, and the present invention does not specify the battery system as follows. Further, this specification does not limit the members shown in the claims to the members of the embodiments.

  The battery system shown in the following embodiments is mainly suitable for the power source of an electric vehicle such as a hybrid car that runs with both an engine and a motor and an electric vehicle that runs with only a motor. However, it can be used for vehicles other than hybrid cars and electric cars, and can also be used for applications requiring high output other than electric vehicles.

  2 to 4, the battery system includes a battery block 2 to which a plurality of battery cells 1 having gas discharge valves 11 are connected, and a gas discharge valve 11 of each battery cell 1 constituting the battery block 2. The battery block 2 is connected to the discharge port 12 and has a hollow discharge duct 20 that exhausts the gas discharged from the gas discharge port 12 to the outside. 30.

  In the battery block 2 of FIGS. 5 to 7, the battery cell 1 is a rectangular battery cell 1A, and a plurality of rectangular battery cells 1A are stacked to form a battery block 2. The battery block 2 is fixed by a battery holder 3 on the outside. In the battery system shown in the figure, a plurality of, in the figure, four sets of battery blocks 2 are arranged vertically and horizontally on the same surface. As shown in FIG. 8, the rectangular battery cell 1 </ b> A has a posture in which the outer peripheral surface 10 provided with the gas discharge ports 12 is arranged on the same surface, and is laminated through an insulating separator 15 to form a battery block 2. A hollow discharge duct 20 that exhausts the gas discharged from the gas discharge port 12 to the outside is disposed so as to be connected to the gas discharge port 12 of the rectangular battery cell 1 </ b> A constituting the battery block 2. The rectangular battery cell 1 </ b> A in the figure is stacked in a posture with the outer peripheral surface 10 provided with the gas discharge valve 11 as the upper surface.

  As shown in the drawing, the prismatic battery cell 1A is a rectangular battery having a width wider than the thickness, in other words, a rectangular battery thinner than the width, and is stacked in the thickness direction to form a battery block 2. This rectangular battery cell 1A is a lithium ion secondary battery. However, the square battery cell may be a secondary battery such as a nickel metal hydride battery or a nickel cadmium battery. The rectangular battery cell 1A shown in the figure is a battery having a rectangular shape with both wide surfaces, and the battery blocks 2 are laminated so that both surfaces face each other. In the illustrated rectangular battery cell 1A, a gas discharge port 12 of a gas discharge valve 11 is provided at the center of the upper surface. Although not shown, the square battery cell is provided with positive and negative electrode terminals 13 protruding from both ends of the upper surface.

  The gas discharge valve 11 is opened when the internal pressure of the rectangular battery cell 1A is higher than the set pressure, thereby preventing the internal pressure from increasing. The gas discharge valve 11 incorporates a valve body (not shown) that closes the gas discharge port 12. The valve body is a thin film that is destroyed at a set pressure, or a valve that is pressed against the valve seat by an elastic body so as to open at the set pressure. When the gas discharge valve 11 is opened, the inside of the rectangular battery cell 1A is opened to the outside through the gas discharge port 12, and the internal gas is discharged to prevent the internal pressure from increasing.

  The adjacent rectangular battery cells 1A are connected in series with each other by connecting positive and negative electrode terminals 13 (not shown). In the battery system, positive and negative electrode terminals 13 of adjacent rectangular battery cells are connected in series with each other through a bus bar. A battery system in which adjacent rectangular battery cells are connected in series can increase the output voltage and increase the output. However, the battery system can also connect adjacent rectangular battery cells in parallel.

  As shown in FIG. 8, the battery block 2 has an insulating separator 15 sandwiched between the stacked rectangular battery cells 1A. The insulating separator 15 insulates adjacent rectangular battery cells 1A. Although not shown, the insulating separator 15 can be laminated so that the adjacent rectangular battery cells 1A are not displaced as a shape in which the rectangular battery cells 1A are fitted on both surfaces and arranged in a fixed position. The rectangular battery cell 1A that is insulated and stacked by the insulating separator 15 can have an outer can made of metal such as aluminum. The structure in which the insulating separator 15 is sandwiched between the prismatic battery cells 1A can effectively prevent thermal runaway of the adjacent prismatic battery cells 1A by manufacturing the insulating separator 15 with a material having low thermal conductivity such as plastic. There is also an effect.

  The insulating separator 15 stacked on the prismatic battery cell 1A is provided with a cooling gap 16 through which a cooling gas such as air passes between the prismatic battery cell 1A in order to effectively cool the prismatic battery cell 1A. . The insulating separator 15 in FIG. 8 is provided with grooves 15A extending to both side edges on the surface facing the rectangular battery cell 1A, and a cooling gap 16 is provided between the rectangular battery cell 1A. The insulating separator 15 is provided with a plurality of grooves 15A in parallel with each other at a predetermined interval. The insulating separator 15 is provided with grooves 15 </ b> A on both surfaces, and a cooling gap 16 is provided between the adjacent rectangular battery cells 1 </ b> A and the insulating separator 15. This structure has an advantage that the square battery cells 1A on both sides can be effectively cooled by the cooling gaps 16 formed on both sides of the insulating separator 15. However, the insulating separator can be provided with a groove only on one side, and a cooling gap can be provided between the rectangular battery cell 1A and the insulating separator. The cooling gap 16 is provided in the horizontal direction so as to open to the left and right of the battery block 2. The air forcedly blown into the cooling gap 16 directly and efficiently cools the outer can of the rectangular battery cell 1A. This structure is characterized in that the prismatic battery cell 1A can be efficiently cooled while effectively preventing thermal runaway of the prismatic battery cell 1A.

  A battery holder 3 that fixes the rectangular battery cells 1A in a stacked state to form a battery block 2 includes a pair of end plates 4 sandwiching the battery block 2 from both end surfaces, and a pair of end plates 4 at both ends or in the middle. And a connecting fixture 5 formed by connecting the parts.

  The end plate 4 is formed as a quadrangle having the same shape and dimensions as the outer shape of the rectangular battery cell 1A, and the stacked battery blocks 2 are sandwiched and fixed from both end surfaces. The end plate 4 is made of plastic or metal, and is provided with integrally formed reinforcing ribs extending vertically and horizontally on the outer surface. The end plate can be reinforced by fixing a reinforcing metal fitting. Further, the connecting fixture can be fixed to the reinforcing metal fitting. This structure is characterized in that the end plate can be reinforced with a reinforcing metal fitting to be a strong structure, and the connection fixture can be firmly connected. In particular, this structure is characterized in that the end plate can be molded from plastic to make itself strong. However, it is not always necessary to reinforce the end plate with the reinforcing metal fitting. For example, the end plate is made of metal, and the connecting fixture can be directly fixed without providing the reinforcing metal fitting.

  The connection fixture 5 is made of metal such as iron, and both ends or the middle thereof are fixed to the end plate 4 with set screws (not shown).

  In the battery system shown in FIGS. 3 to 7, the discharge duct 20 is arranged on the upper surface of each battery block 2. 9 and 10 are a perspective view and an exploded perspective view of the discharge duct 20, respectively, and FIG. 11 is an enlarged sectional view of the discharge duct 20. The discharge duct 20 is formed of an insulating plastic. The insulating plastic is a plastic such as nylon resin or epoxy resin. However, the discharge duct can be made of metal. Although not shown, the discharge duct may be made of a metal plate on the upper side and made of plastic on the lower side. In this discharge duct, the upper half is made of a metal plate, the lower half is made of plastic, and the lower side facing the rectangular battery cell is made of an insulating plastic. Even if the discharge duct comes into contact with the surface of the rectangular battery cell, the discharge duct does not short-circuit the outer can of the rectangular battery cell. In the battery block 2 in which a large number of rectangular battery cells 1A are stacked, adjacent rectangular battery cells 1A are connected in series to increase the output voltage. The battery block 2 has a potential difference between the outer cans of the adjacent rectangular battery cells 1A. Therefore, when the discharge duct 20 contacts the outer can of the adjacent rectangular battery cell 1A, the outer can having a potential difference is short-circuited. The discharge duct 20 made of an insulating plastic on the lower side facing the battery block 2 or the discharge duct 20 made entirely of an insulating plastic is not short-circuited even if it contacts the outer can of the rectangular battery cell 1A.

  The discharge duct 20 is disposed between the battery block 2 and the outer case 30. In this battery system, the discharge duct 20 is elastically pressed against the battery block 2 by the outer case 30 and is arranged at a fixed position. The battery system of FIGS. 3, 8, and 11 includes an elastic pressing member 21 that elastically presses the discharge duct 20 against the surface of the battery block 2 between the outer case 30 and the discharge duct 20. Provided. The discharge duct 20 is provided with a connecting boss 24 on the upper surface in order to place the elastic pressing member 21 at a fixed position. The connecting boss 24 has a cylindrical shape that opens upward, and is placed in a fixed position with the elastic pressing material 21 inside. The elastic pressing member 21 protrudes from the connection boss 24 and contacts the inner surface of the exterior case 30. The connecting boss 24 is integrally formed with the plastic discharge duct 20. The discharge ducts 20 are provided with connecting bosses 24 at a plurality of positions on the upper surface, in FIGS. 9 and 10, at four or five positions of the discharge duct 20 in one row. In the battery system of FIGS. 4 to 6, four sets of battery blocks 2 are arranged in an outer case 30, and a discharge duct 20 is provided in each battery block 2. Therefore, four rows of discharge ducts 20 are provided on the four sets of battery blocks 2, and four or five connecting bosses 24 are provided in each discharge duct 20.

  The elastic pressing member 21 is a rubber-like elastic body. However, the elastic pressing material does not necessarily need to be a rubber-like elastic body, and for example, a pressing spring can be used. The elastic pressing member 21 is elastically deformed and elastically presses the discharge duct 20 against the surface of the battery block 2 by the exterior case 30. The battery system that elastically presses the discharge duct 20 against the battery block 2 with the outer case 30 via the elastic pressing member 21 increases the amount of elastic deformation, that is, the stroke that can be elastically deformed, by elastically deforming the elastic pressing member 21. Thus, the discharge duct 20 can be effectively pressed against the battery block 2. However, the battery system of the present invention does not necessarily need to be provided with an elastic pressing material. This is because the outer case 30 and the discharge duct 20 can be elastically deformed to press the discharge duct 20 against the surface of the battery block 2. The outer case 30 can be elastically deformed as a metal plate or a hard plastic, particularly a plastic reinforced with fibers. Also, the discharge duct 20 can be made of a hard plastic or metal plate and elastically deformed.

  Further, in the battery system shown in FIGS. 8, 10, and 11, a packing 22 that is elastically deformed is disposed between the discharge duct 20 and the battery block 2. In the battery system of FIGS. 4 to 6, four sets of battery blocks 2 are arranged in the outer case 30, so that four packings 22 are arranged on the four sets of battery blocks 2. That is, one packing 22 is disposed on one set of battery blocks 2. This structure can effectively prevent gas leakage between the discharge duct 20 and the rectangular battery cell 1 </ b> A by the packing 22. However, although not shown, a plurality of divided packings 22 can be arranged in one set of battery blocks 2 to prevent gas leakage between the gas discharge port 12 and the rectangular battery cell 1A.

  The elastic coefficient of the packing 22 is larger than the elastic coefficient of the elastic pressing material 21, that is, the packing 22 is made of a material that is more flexible than the elastic pressing material 21. The packing 22 is sandwiched between the battery block 2 and the discharge duct 20 and is elastically deformed to a greater extent than the elastic pressing member 21. That is, in the state where the outer case 30 presses the discharge duct 20 against the battery block 2, the elastic displacement of the packing 22, that is, the dimension to be crushed, is larger than the dimension in which the elastic pressing member 21 is elastically displaced. The packing 22 is sandwiched between the discharge duct 20 and the battery block 2 and is crushed to a compression rate of, for example, 20% to 70% to reliably close the gap between the discharge duct 20 and the rectangular battery cell 1A. The compression rate is the ratio of the size that is sandwiched and crushed to the thickness of the packing 22 that is not pressed. Therefore, when the packing 22 having a thickness of 10 mm is crushed to 5 mm, the compression rate becomes 50%. The elastically deformable packing 22 is made of a soft plastic foam having closed cells. The packing 22 made of a plastic foam can have a size that can be flexibly and elastically deformed by closed cells. Further, gas permeation can be prevented by the structure foaming into closed cells. However, the packing does not necessarily need to be a closed-cell foamed plastic, and all rubber-like elastic bodies that are easier to deform than the elastic pressing material can be used.

  The packing 22 is provided with a fitting groove 22C for the discharge duct 20 on the surface facing the discharge duct 20, and in FIG. 10 and FIG. The packing 22 of FIG. 10 is provided with a fitting groove 22C along the outer peripheral edge. On the other hand, as shown in FIG. 11, the discharge duct 20 is provided with a ridge 25 that is guided, that is, inserted into the fitting groove 22C. The protrusions 25 are inserted into the fitting grooves 22 </ b> C, and the packing 22 and the discharge duct 20 are connected to a fixed position, and gas leakage between the discharge duct 20 and the packing 22 is reliably prevented. The discharge duct 20 allows the gas discharged from the gas discharge port 12 of the rectangular battery cell 1 </ b> A to flow inside the ridge 25.

  Further, the packing 22 in FIGS. 8 and 10 is provided with a through hole 22A at a position facing the gas discharge port 12 of each rectangular battery cell 1A. Between the through holes 22A, there is provided a boundary closing portion 22B for closing the stacking gap 14 formed at the boundary of the stacked rectangular battery cells 1A. The packing 22 of FIG. 10 is provided with an elliptical through hole 22A, which is connected to the gas discharge port 12 of the rectangular battery cell 1A. The through hole 22 </ b> A is inside a fitting groove 22 </ b> C provided on the outer peripheral edge of the packing 22, and allows the gas passing through the through hole 22 </ b> A to flow into the discharge duct 20.

  In the battery block 2 of FIG. 8, the insulating separator 15 is sandwiched between the rectangular battery cells 1 </ b> A, so that the stacking gap 14 of the rectangular battery cell 1 </ b> A can be formed on both surfaces of the insulating separator 15. The boundary closing portion 22 </ b> B is wider than the stacking gap 14 to close the stacking gap 14 on both surfaces of the insulating separator 15. In this structure, the stacking gap 14 of the rectangular battery cell 1A is closed by the boundary closing portion 22B of the packing 22, so that it is ensured that the gas discharged from the gas discharge port 12 flows into the stacking gap 14 of the prismatic battery cell 1A. Can be prevented.

  As shown in FIG. 11, the packing 22 is connected to a fixed position of the gas discharge port 12 by inserting the protrusion 25 of the discharge duct 20 into the fitting groove 22 </ b> C. That is, it is integrally connected to the discharge duct 20. This structure can arrange | position the discharge duct 20 in a fixed position, and can also arrange packing 22 in a fixed position.

  Further, in the battery system of FIGS. 5 and 6, the discharge duct 20 is disposed at a fixed position by the insulating separator 15 of the battery block 2. In order to realize this, the insulating separator 15 is provided with a protruding portion 15B that protrudes upward from the outer periphery of the battery block 2. This protrusion 15B is provided on both sides of the discharge duct 20, and the discharge duct 20 is arranged at a fixed position with the protrusion 15B. Further, as shown in FIGS. 9, 12, and 13, the discharge duct 20 includes a first positioning rib 26 that prevents displacement in the longitudinal direction, and a first displacement rib that prevents displacement in the direction orthogonal to the longitudinal direction. Two positioning ribs 27 are provided so as to protrude on both sides. The first positioning ribs 26 are in contact with the end faces of the partition ribs 15C provided on the protruding portions 15B of the insulating separator 15 so as to extend in the stacking direction of the rectangular battery cells 1A, thereby preventing positional displacement in the longitudinal direction. . The pair of first positioning ribs 26 projecting on both sides of the discharge duct 20 have their respective side surfaces in contact with the end faces on the opposite side of the partition ribs 15C, so that the displacement of the discharge duct 20 in the longitudinal direction is prevented. Blocking. The second positioning rib 27 is in contact with the side surface of the partition rib 15C provided on the protruding portion 15B of the insulating separator 15 so as to extend in the stacking direction of the rectangular battery cells 1A, and is displaced in the direction orthogonal to the longitudinal direction. Is blocking. The discharge duct 20 is provided with the first positioning ribs 26 and the second positioning ribs 27 on both surfaces thereof to prevent the positional deviation in the longitudinal direction and the positional deviation in the direction orthogonal thereto.

  As shown in FIG. 3, the insulating separator 15 is provided with a protruding portion 15 </ b> B at a cover portion 17 that covers the electrode terminal 13 of the rectangular battery cell 1 </ b> A. Since the cover part 17 covers the electrode terminal 13 protruding from the surface of the rectangular battery cell 1 </ b> A, the cover part 17 is provided protruding from the surface of the battery block 2. The cover portion 17 of the electrode terminal 13 shown in FIGS. 3, 12, and 13 is provided with an opening / closing cover 17 </ b> A that opens and closes the electrode terminal 13. At the closed position of the opening / closing cover 17A, the discharge duct 20 is disposed at a fixed position with the first positioning ribs 26 on both sides contacting the protruding portion 15B.

  Furthermore, the battery system shown in FIGS. 5, 6, and 9 has a structure in which a connection duct 23 that connects four discharge ducts 20 is arranged at a fixed position of the battery block 2. In this battery system, a connection plate 18 is fixed between battery blocks 2 arranged in two rows, and a connection duct 23 is connected to the connection plate 18. As shown in FIGS. 14 and 15, the connecting plate 18 is provided with a connecting hole 18 </ b> B for arranging the connecting duct 23 at a fixed position. The connection duct 23 is provided with a connection convex portion 29 inserted into the connection plate 18 so as to protrude from the lower surface. In order to provide the connection convex part 29, the connection duct 23 of FIG. 15 is provided with a connection arm 28 so as to protrude on both sides thereof. The connecting arm 28 is provided with a connecting projection 29 protruding on the lower surface. A connecting projection 29 provided on the connecting arm 28 is inserted into the connecting hole 18 </ b> B, and the connecting duct 23 is connected to a fixed position of the connecting plate 18. The connecting plate 18 is fixed to the two rows of battery blocks 2 and arranged at a fixed position of the battery blocks 2. Therefore, in this battery system, the discharge duct 20 is arranged at a fixed position of the battery block 2 by arranging the connecting duct 23 at a fixed position of the connecting plate 18.

  2 to 7, four battery blocks 2 are arranged in two rows, and two rows of discharge ducts 20 are arranged on the upper surface. Two rows of discharge ducts 20 are connected to a connection duct 23 in the center of the battery system, and the discharge duct 20 and the connection duct 23 are connected in an H shape. The connecting duct 23 located at the center exhausts the exhaust gas flowing in from the respective exhaust ducts 20 to the outside. Therefore, an external duct (not shown) that exhausts to the outside is connected to one end of the connection duct 23. The discharge duct 20 is open at one end and connected to the connection duct 23 and closes the other end. The discharge duct 20 flows the gas discharged from the gas discharge port 12 into the discharge duct 20 from the through hole 22 </ b> A of the packing 22, and discharges the gas to the outside from the connection duct 23. In the above battery system, two rows of discharge ducts 20 are connected at the center and exhausted to the outside, but two rows of discharge ducts can be connected at both ends to be exhausted to the outside.

  In the battery system shown in FIGS. 2 to 4, the battery block 2 is housed in an outer case 30. The illustrated outer case 30 includes a lower case 31 and an upper case 32. In the battery system, a plurality of battery blocks 2 are arranged side by side in an exterior case 30 and fixed. In the battery system shown in FIG. 4, two battery blocks 2 are arranged in series on a lower case 31 and arranged in two rows to accommodate four battery blocks 2. The battery blocks 2 arranged in two rows are arranged apart from each other so that an air duct 33 is formed between them.

  The lower case 31 and the upper case 32 are metal plates processed into a groove shape. The lower case 31 and the upper case 32 are made of a metal plate having the same thickness, or the lower case 31 is made of a metal plate thicker than the upper case 32. The lower case 31 and the upper case 32 are provided with side wall portions 31A and 32A on both sides to form a groove shape. In the illustrated battery system, the width of the lower case 31 is wider than that of the upper case 32, and an electronic component case (not shown) can be disposed between the side wall portion 32A of the lower case 31 and the side wall portion 31A of the upper case 32. I am doing so. The lower case 31 has a width corresponding to the width of the electronic component case wider than the width of the upper case 32. That is, the width of the lower case 31 is a width obtained by adding the width of the electronic component case to the width of the upper case 32.

  In the lower case 31, one side wall 31 </ b> A provided on the left side in FIG. 3 is fixed to the side wall 32 </ b> A of the upper case 32. The right side wall portion 32A of the upper case 32 is fixed to the bottom portion of the lower case 31, and partitions the storage portion of the battery block 2 and the storage portion of the electronic component case. The right side wall 32 </ b> A of the upper case 32 fixed to the bottom is made higher than the left side wall 32 </ b> A so that the lower end edge can be fixed to the bottom of the lower case 31. The lower case 31 and the upper case 32 are provided with bent pieces 31a and 32a that are bent outward at the front end edges that are fixed to each other. The bent pieces 31a, 32a are fixed by a set screw (not shown) and a nut (not shown) penetrating the bent pieces 31a, 32a, or fixed by a rivet or the like passing through the bent pieces, and the lower case 31 and the upper case 32 are connected.

  The battery system shown in FIG. 3 is provided with side wall portions 31 </ b> A having substantially the same height on both sides of the lower case 31. In the figure, the left side wall portion 31 </ b> A of the lower case 31 fixes the left side wall portion 32 </ b> A of the upper case 32. The right side wall portion 31 </ b> A of the lower case 31 is not fixed to the side wall portion 32 </ b> A of the upper case 32, but the side wall portion of the fixing plate (not shown) of the electronic component case fixed to the upper case 32 is fixed. The upper case 32 also has side walls 32A on both sides. In the figure, the right side wall portion 32A of the upper case 32 has a height higher than that of the left side wall portion 32A, and the lower side wall portion 32A is fixed to the left side wall portion 31A of the lower case 31 to increase the height. The high-right side wall 32 </ b> A is fixed to the bottom of the lower case 31.

  Although the upper case 32 is not illustrated, a fixing plate of the electronic component case is fixed to the upper end of the right side wall portion 32A. The fixed plate has a shape in which a metal plate is processed into an L shape and a side wall is provided on one side of the top plate. In this fixing plate, the edge of the top plate is fixed to the upper edge of the side wall portion 32A of the upper case 32, and the bent piece provided at the lower edge of the side wall portion is the upper end of the right side wall portion 31A of the lower case 31. It fixes to the bending piece 31a provided in. The fixed plate and the lower case 31 are connected by fixing the bent piece of the fixed plate and the bent piece 31 a of the lower case 31. In the outer case 30 having this structure, the side wall portion 32A provided on the right side of the upper case 32 partitions the storage portion of the battery block 2 and the electronic component case.

  The outer case 30 including the lower case 31 and the upper case 32 is wide so that an air duct 33 is formed outside the battery block 2. The battery system of FIG. 3 is provided with an air duct 33 in the middle of the battery blocks 2 arranged in two rows, and further provided with an air duct 33 outside the battery block 2 and between the side walls 31A and 32A. ing. In this battery system, one of an intermediate air duct 33A formed in the middle of two rows of battery blocks 2 and a side air duct 33B formed outside the battery block 2 is used as a cooling air supply duct, and the other Is discharged into the cooling gap 16 between the battery cells 1 as a discharge duct 20 to cool the battery cells 1.

  The battery system shown in FIG. 3 is provided with a side air duct 33B between the outside (right side in the figure) of the battery block 2 and the side wall portion 32A of the upper case 32, and outside the side air duct 33B. A storage space for the electronic component case is provided outside the side wall portion 32A of the upper case 32 constituting the side air duct 33B. In this structure, a side air duct 33 </ b> B and a side wall 32 </ b> A are provided between an electronic component (not shown) housed in an electronic component case and the battery block 2. With this structure, the heat of the battery block 2 does not heat the electronic component, and it is possible to prevent adverse effects caused by the heat generated by the battery block 2 on the electronic component.

  The intermediate air duct 33 </ b> A provided between the two rows of battery blocks 2 has an upper opening closed by the connecting plate 18 and a lower opening closed by the lower case 31. The connecting plate 18 is a narrow metal plate extending along the intermediate air duct 33A formed between the two rows of battery blocks 2, and is fixed to the battery blocks 2 on both sides to close the opening on the upper surface of the intermediate air duct 33A. To do. The connecting plate 18 is fixed to the upper surface of the end plate 4 of the battery block 2 disposed on both sides via a set screw. The connecting plate 18 can be fixed to the battery block 2 via a set screw penetrating the projecting portion 18A by providing projecting portions 18A on both sides of both end portions and both sides in the middle.

  The outer case 30 fixes the battery block 2 by fixing the lower case 31 to the end plate 4 with a set screw (not shown). The set screw passes through the lower case 31 and is screwed into a screw hole (not shown) of the end plate 4 to fix the battery block 2 to the exterior case 30. The set screw projects the head from the lower case 31. Furthermore, the lower case 31 is provided with a ridge 31 </ b> B protruding downward along a direction orthogonal to the stacking direction of the battery blocks 2. These ridges 31 </ b> B reinforce the lower case 31 and increase the bending strength of the lower case 31. Furthermore, the ridges 31 </ b> B provided on the lower surface of the lower case 31 protrude below the head of the set screw that fixes the battery block 2, or have the same height as the head. When the lower case 31 is mounted on a vehicle or the like, the ridge 31B can be placed on a fixed plate of the vehicle to support the load of the battery system over a wide area.

DESCRIPTION OF SYMBOLS 1 ... Battery cell 1A ... Rectangular battery cell 2 ... Battery block 3 ... Battery holder 4 ... End plate 5 ... Connection fixture 10 ... Outer peripheral surface 11 ... Gas exhaust valve 12 ... Gas exhaust port 13 ... Electrode terminal 14 ... Lamination gap 15 ... Insulating separator 15A ... groove
15B ... Projection
15C: Partition rib 16 ... Cooling gap 17 ... Cover part 17A ... Opening / closing cover 18 ... Connecting plate 18A ... Projecting part
18B ... Connection hole 20 ... Discharge duct 21 ... Elastic pressing material 22 ... Packing 22A ... Through hole
22B ... Boundary blockage
22C ... Fitting groove 23 ... Connecting duct 24 ... Connecting boss 25 ... Convex strip 26 ... First positioning rib 27 ... Second positioning rib 28 ... Connecting arm 29 ... Connecting projection 30 ... Exterior case 31 ... Lower case 31A ... Side wall
31a ... Folded piece
31B ... ridge 32 ... upper case 32A ... side wall
32a ... bent piece 33 ... air duct 33A ... intermediate air duct
33B ... Side air duct 91 ... Square battery cell 92 ... Battery block 93 ... Exterior case 94 ... Exhaust duct 95 ... Gas outlet

Claims (9)

The battery block (2) is formed by stacking a plurality of rectangular battery cells (1A) in a posture in which the gas discharge port (12) of the gas discharge valve (11) is arranged on the same surface, and the battery block (2) is configured. A hollow discharge duct (20) disposed opposite to the gas discharge port (12) of each rectangular battery cell (1A) and exhausting the gas discharged from the gas discharge port (12) to the outside, A battery system comprising an outer case (30) housing a battery block (2) having a discharge duct (20) disposed therein,
The battery system, wherein the outer case (30) is arranged at a fixed position by elastically pressing the discharge duct (20) against the battery block (2).   Between the outer case (30) and the discharge duct (20), an elastic pressing material (21) is provided for the outer case (30) to elastically press the discharge duct (20) against the surface of the battery block (2). The battery system according to claim 1, wherein the battery system is disposed.   The battery system according to claim 2, wherein a packing (22) that is elastically deformed is disposed between the discharge duct (20) and the battery block (2).   The elastic coefficient of the packing (22) is larger than the elastic coefficient of the elastic pressing material (21), and is pressed against the exterior case (30), so that the elastic displacement of the packing (22) is the elastic pressing material (21). The battery system according to claim 3, wherein the battery system is larger than the elastic displacement.   The packing (22) includes a fitting groove (22C) of the discharge duct (20) on a surface facing the discharge duct (20), and the discharge duct (20) is guided by the fitting groove (22C). The ridge (25) is provided, the ridge (25) is guided by the fitting groove (22C), and the packing (22) and the discharge duct (20) are connected to a fixed position. Battery system.   The packing (22) is provided with a through hole (22A) at a position opposite to the gas discharge port (12) of each rectangular battery cell (1A), and is laminated between the through holes (22A). The battery system according to claim 3, further comprising a boundary closing portion (22B) for closing a stacking gap (14) formed at a boundary of the rectangular battery cell (1A).   The battery system according to claim 3, wherein the packing (22) is a plastic foam having closed cells.   The battery block (2) has an insulating separator (15) disposed between the rectangular battery cells (1A), and the insulating separator (15) protrudes from the outer periphery of the battery block (2) (15B). The protrusion (15B) is provided on both sides of the discharge duct (20), and the discharge duct (20) is arranged at a fixed position with the protrusion (15B). Battery system.   The battery system according to claim 8, wherein the protruding portion (15B) of the insulating separator (15) is a cover portion (17) of the electrode terminal (13) of the rectangular battery cell (1A).

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