JP5601283B2 - Power storage device, spacer - Google Patents

Description

  The present invention relates to a technique of a spacer disposed between adjacent power storage elements.

  In recent years, electric vehicles, hybrid vehicles, and the like equipped with an electric motor for running a vehicle have been attracting attention and put into practical use as vehicles conscious of the global environment. The electric motor is driven by electric power output from a chargeable / dischargeable power storage device.

  As this type of power storage device, there is known a power storage device in which a stacked body in which power storage elements containing power generation elements in a case and spacers are alternately stacked is constrained in a stacking direction by a restraining member. The spacer is formed with a rib for forming a coolant passage, and the rib is bent when pressed against the case.

JP 2009-081056 A JP 2008-053072 A

  However, in the above-described configuration, the bent rib contacts the main body portion of the spacer and is pressed between the case and the spacer, so that a load is applied to the outer surface of the case. When the power storage device mounted on the vehicle vibrates, the rib slides along the outer surface of the case, and the case receives sliding wear.

  Then, an object of this invention is to suppress the load added to the case of an electrical storage element from the rib which forms a refrigerant path.

  In order to solve the above-described problems, the power storage device of the present invention includes (1) a power storage device in which a stacked body in which a power storage element containing a power generation element and a spacer are alternately stacked in a case is constrained in a stacking direction by a restraining member The spacer includes a facing surface facing the adjacent power storage element, and a first rib that forms a refrigerant passage for a refrigerant flowing along the facing surface, wherein the first rib is The bent portion is bent by coming into contact with the case, and a concave portion into which at least a part of the bent first rib enters is formed on the facing surface.

(2) In the configuration of (1), a gap may be formed between the concave portion and the bent first rib in the stacking direction. According to the structure of (2), since the 1st rib is not pinched by the case and the recessed part, the load added to a case from a 1st rib can be suppressed.

(3) In the configuration (2), the dimensions of the recess in the front Symbol stacking direction is t1, by the dimensions of the root portion of the first rib in a state where the first rib is not in contact with the said casing It is preferable that t1> t2 is satisfied when t2 is the maximum dimension in the direction orthogonal to the direction in which the first rib protrudes from the facing surface . According to the configuration of (3), the effect of (2) can be obtained with certainty.

(4) In the configurations of (1) to (3), the case extends at least in a pair of first case side surfaces facing each other and in a direction orthogonal to the first case side surfaces and faces each other. A second case side surface and an R-shaped corner that connects the adjacent first case side surface and the second case side surface are provided, and the first rib contacts at least the corner.
According to the configuration of (4), it is possible to protect corners where sliding wear is particularly likely to occur.

(5) In the configuration of (4), the opposing surface includes a plurality of second ribs that are located in the refrigerant passage and extend in a passage direction of the refrigerant passage, and the first of the cases is the first rib. The plurality of second ribs that contact only the side surface of one case are formed. According to the structure of (5), since the 2nd rib does not contact | abut to the corner | angular part which a sliding wear tends to occur, the sliding wear of a case can be suppressed.

(6) In the above configurations (1) to (5), the spacer may be a resin. According to the structure of (6), each element which comprises spacers, such as a 1st rib and a 2nd rib, can be integrally shape | molded by the injection molding method. Thereby, cost can be reduced.

In order to solve the above-mentioned problems, the spacer according to the present invention is (7) a power storage device in which a power storage element in which a power generation element is housed in a case and a stacked body in which spacers are alternately stacked are constrained in the stacking direction by a restraining member. The spacer used in the apparatus, comprising: a facing surface that faces the adjacent power storage element; and a first rib that forms a refrigerant passage for a refrigerant that flows along the facing surface,
The first rib is bent by coming into contact with the case, and a concave portion into which at least a part of the bent first rib enters is formed on the facing surface.

  ADVANTAGE OF THE INVENTION According to this invention, the load added to the case of an electrical storage element from the rib which forms a refrigerant path can be reduced.

It is a perspective view of a power storage device. It is a disassembled perspective view of an electrical storage apparatus. It is an external view of the spacer seen from the X-axis direction. It is the perspective view which expanded and illustrated the edge part of the 1st rib (before contact). It is a fragmentary sectional view of the 1st rib and an electrical storage element (normal time). It is a fragmentary sectional view of the 1st rib and an electrical storage element (at the time of strong interference). It is a fragmentary sectional view of the 1st rib and electric storage element concerning modification 1 (at the time of strong interference).

  A schematic configuration of a power storage device according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. 1 is a perspective view of the power storage device, and FIG. 2 is an exploded perspective view of the power storage device. The arrows in FIG. 1 indicate the intake direction and the exhaust direction. In FIG. 2, the intake chamber, the exhaust chamber, and the restraining band are omitted. In these drawings, the X axis, the Y axis, and the Z axis are three different axes orthogonal to each other.

  The power storage device 1 includes a stacked body in which battery cells (power storage elements) 11 and spacers 13 are alternately stacked. End plates 14 are positioned at both ends in the stacking direction of the stacked body. The restraint band 16 extends in the X-axis direction along the upper end surface of the power storage device 1, and both end portions thereof are bent downward. By fixing the bent portion to the end plate 14, the pair of end plates 14 are pressurized in a direction approaching each other. Thereby, the some battery cell 11 is restrained. The power storage device 1 is mounted on a vehicle. The vehicle may be a hybrid vehicle or an electric vehicle. The power storage device 1 mounted on the vehicle vibrates when the vehicle travels.

  The battery cell 11 includes a case 110 and a power generation element (not shown) accommodated in the case 110. On the upper surface of the case 110, the positive electrode terminal 11a and the negative electrode terminal 11b are located. A stepped positive electrode side connection electrode 11c is connected to the positive electrode terminal 11a. The positive electrode side connection electrode 11c is electrically connected to the power generation element in the case 110 via a conductive member (not shown). A step-shaped negative electrode side connection electrode 11d is connected to the negative electrode terminal 11b. The negative electrode side connection electrode 11d is electrically connected to the power generation element in the case 110 via a conductive member (not shown). The battery cell 11 may be a secondary battery such as a lithium ion battery. Adjacent battery cells 11 are connected in series via a bus bar (not shown).

  Referring to FIG. 2, case 110 includes a pair of first case side faces 110a facing each other, and a pair of second case side faces 110b extending in a direction orthogonal to first case side face 110a and facing each other. And a corner portion 110c that connects the first case side surface 110a and the second case side surface 110b. The corner 110c is formed in an R shape. Aluminum can be used for the case 110.

  The battery cell 11 expands when the power generation element is charged and discharged, and the pair of case side surfaces 110a expand in a direction away from each other. Therefore, the pressing force applied from the spacer 13 to the outer surface of the case 110 varies.

  Referring to FIG. 1, an intake chamber 17 for introducing a refrigerant into power storage device 1 is attached to one end surface in the Y-axis direction of power storage device 1, and the other end surface is introduced from intake chamber 17. After that, an exhaust chamber 18 for exhausting the cooling air used for cooling the battery cells 11 is attached.

  Next, the configuration of the spacer 13 will be described with reference to FIGS. 2 and 3. FIG. 3 is an external view of the spacer viewed from the X-axis direction. In the figure, dotted lines indicate the outlines of the case 110, the positive terminal 11a, and the negative terminal 11b.

  The spacer 13 includes a spacer facing surface (facing surface) 131, a first rib 13a, a second rib 13b, a spacer leg 13c, and an upper protrusion 13d. Resin can be used for the spacer 13. The spacer facing surface 131 faces the first case side surface 110 a in the adjacent battery cell 11. The first rib 13a forms a coolant passage in a region sandwiched between the spacer facing surface 131 and the first case side surface 110a. That is, the first rib 13a contacts the first case side surface 110a and the corner 110c of the case 110, thereby preventing the refrigerant from flowing out in the Z-axis direction from the refrigerant passage.

  Referring to FIG. 3, first rib 13a located on the upper side has linear rib portion 131a extending along second rib 13b, and an inclination extending obliquely from the end of linear rib portion 131a toward upper protruding portion 13d. Rib part 131b. The linear rib portion 131a has substantially the same length in the Y-axis direction as the second rib 13b, and is in contact with the first case side surface 110a of the case 110. The inclined rib portion 131b is in contact with the first case side surface 110a and the corner portion 110c of the case 110.

  The first rib 13a located on the lower side extends along the second rib 13b, is located at substantially the same height as the upper end surface of the spacer leg 13c, and has the first case side surface 110a and the corner portion 110c. Abut.

  The second rib 13b is located inside the refrigerant passage. The second rib 13b extends in the direction of the refrigerant passage. A plurality of second ribs 13b are provided at a predetermined interval in the Z-axis direction. The second rib 13b contacts only the first case side surface 110a of the case 110 and does not contact the corner 110c.

  The spacer legs 13c are located on both end surfaces of the spacer 13 in the Y-axis direction. The spacer leg 13 c supports the spacer 13. The spacer legs 13c adjacent in the X-axis direction are in contact with each other in the assembled state of the power storage device 1 (see FIG. 2).

  Next, the configuration of the first rib 13a will be described in detail with reference to FIG. FIG. 4 is an enlarged perspective view of the end of the first rib 13a located on the lower side in the Y-axis direction, and shows a state before coming into contact with the first case side surface 110a. The first rib 13a extends in the downward oblique direction. On the spacer facing surface 131, a recess 131c is formed at a position facing the first rib 13a when the first rib 13a is bent in the direction of the arrow. Here, when the depth in the X-axis direction (stacking direction of the battery cell 11 and the spacer 13) of the recess 131c is t1, and the thickness in the direction orthogonal to the protruding direction of the first rib 13a is t2, t1> It is preferable to satisfy the condition t2.

  Next, the behavior of the first rib 13a when the power storage device 1 is mounted on a vehicle will be described with reference to FIGS. Here, FIGS. 5 and 6 are partial cross-sectional views of the first rib 13a and the case 110, FIG. 5 shows a normal state, and FIG. 6 shows a strong interference state. In these drawings, the spacer 13 is indicated by hatching. Here, the state at the time of strong interference means, for example, a state in which the first rib 13a is strongly pushed to the side approaching the recess 131c by the battery cell 11 expanded by charging and discharging. The normal state means, for example, a state in which the battery cell 11 is stopped and the pressing force applied from the battery cell 11 to the first rib 13a is weaker than that in the strong interference state.

  Referring to FIG. 5, in the assembled state of power storage device 1, first rib 13 a is pushed and bent in the direction of the arrow by the restraining pressure by restraining band 16. At this time, the 1st rib 13a is located in the position spaced apart from the recessed part 131c rather than the spacer opposing surface 131. FIG. Referring to FIG. 6, when the pressing force by battery cell 11 further increases, first rib 13a is further bent toward the inside of recess 131c and moved to a position closer to recess 131c than spacer facing surface 131. To do. However, the first rib 13a does not contact the recess 131c.

  Here, in the configuration in which the concave portion 131c is omitted, the first rib 13a abuts against the spacer facing surface 131 at the time of strong interference, so the first rib 13a is pinched by the first case side surface 110a and the spacer facing surface 131. The pressing force applied from the first rib 13a to the first case side surface 110a and the corner portion 110c increases. Then, when the power storage device 1 mounted on the vehicle vibrates, the first rib 13a slides in a state of being in strong contact with the first case side surface 110a and the corner portion 110c.

  On the other hand, in the configuration of the present embodiment, since at least a part of the first rib 13a enters the recess 131c, the first rib 13a and the spacer facing surface 131 are prevented from interfering with each other. The pressing force applied to the first case side surface 110a and the corner 110c from the first rib 13a can be suppressed. Therefore, sliding wear on the first case side surface 110a and the corner portion 110c can be reduced. Since the upper first rib 13a has the same configuration as the lower first rib 13a, the description thereof is omitted.

  As a technique for preventing the first rib 13a and the battery cell 11 from strongly interfering with each other, a method of configuring the first rib 13a with rubber having a higher elastic coefficient than that of resin can be considered. However, in this method, since the first rib 13a and the other elements in the spacer 13 need to be simultaneously formed by two-color molding, the cost increases. Further, when the power storage device 1 vibrates, the first rib 13a slides on the outer surface of the case 110, so that the rubber may be worn. On the other hand, according to the configuration of the present embodiment, since the spacers 13 are all made of resin, the molding cost can be reduced and the wear of the first ribs 13a can be suppressed.

  Further, as shown in FIG. 3, the present inventors have found that sliding wear is likely to occur particularly in the corner portion 110 c of the portion of the case 110 that contacts the first rib 13 a. That is, it was discovered that when the power storage device 1 vibrates up and down, vibration wear tends to occur particularly at the corner 110c. According to the configuration of the present embodiment, the pressing force applied to the corner portion 110c from the first rib 13a can be reduced, so that sliding wear can be less likely to occur in the corner portion 110c of the case 110.

  Further, when the depth in the X-axis direction (the stacking direction of the battery cells 11 and the spacers 13) of the recess 131c is t1, and the thickness in the direction orthogonal to the protruding direction of the first rib 13a is t2, t1> t2. By configuring so as to satisfy the conditions, it is possible to effectively suppress the bent first rib 13a from coming into contact with the recess 131c. In other words, when the volume per unit length in the Y-axis direction of the recess 131c is V1, and the volume per unit length in the Y-axis direction of the first rib 13a is V2, the condition of V1> V2 is satisfied. With such a configuration, it is possible to effectively suppress the bent first rib 13a from coming into contact with the recess 131c.

  In addition, the contact state between the first rib 13a and the case 110 is maintained both during normal times and during strong interference, so that deterioration in sealing performance can be suppressed. Thereby, the leakage of cooling air is suppressed.

(Modification 1)
In the above-described embodiment, the sizes of the recess 131c and the first rib 13a are set so that a gap is formed between the recess 131c and the first rib 13a during strong interference (the state illustrated in FIG. 6). Although set, the present invention is not limited to this. FIG. 7 is a partial cross-sectional view of the first rib 13a and the case 110 according to Modification 1, and corresponds to FIG. Referring to FIG. 7, the first rib 13a and the recess 131c may contact each other during strong interference. According to the configuration of this modified example, the recess 131c is formed in the spacer facing surface 131, whereby the first rib 13a bends toward the inside of the recess 131c. Therefore, the configuration is stronger than the configuration without the recess 131c. The load applied to the outer surface of the case 110 from the first rib 13a at the time of interference can be reduced.

(Modification 2)
In the above-described embodiment, the recess 131c is formed in the entire region of the spacer facing surface 131 facing the first rib 13a. However, the present invention is not limited to this, and a configuration in which the recess 131c is partially provided may be used. . For example, you may form the recessed part 131c only in the area | region where the 1st rib 13a contact | abutted to the corner part 110c opposes. Thereby, the corner part 110c which is especially easy to receive sliding abrasion among the outer surfaces of the case 110 can be protected.

(Modification 3)
In the above-described embodiment, the first rib 13a extends in the downward oblique direction, but the present invention is not limited to this, and the first rib 13a extends in another direction different from the normal direction of the spacer facing surface 131. There may be. The other direction may be an upper oblique direction. In this case, since the first rib 13a bends in a direction different from that of the above embodiment, the formation position of the recess 131c may be changed according to the bending direction of the first rib 13a.

(Modification 4)
In the above-described embodiment, the refrigerant passage is provided in the horizontal direction. However, the present invention is not limited to this and may be configured in the vertical direction. In this case, the cooling air can be introduced from the surface of the power storage device 1 on the side where the terminal is located.

DESCRIPTION OF SYMBOLS 1 Power storage device 11 Battery cell 11a Positive electrode terminal 11b Negative electrode terminal 13 Spacer 13a 1st rib 13b 2nd rib 13c Spacer leg part 13d Upper protrusion 14 End plate 16 Restraint band 17 Intake chamber 18 Exhaust chamber 110 Case 110a 1st Case side surface 110b Second case side surface 110c Corner portion 131 Spacer facing surface

Claims (7)

A power storage device in which a power storage element in which a power generation element is accommodated in a case and a stacked body in which spacers are alternately stacked is constrained in a stacking direction by a restraining member,
The spacer includes a facing surface that faces the adjacent power storage element, and a first rib that forms a refrigerant passage for a refrigerant that flows along the facing surface.
The first rib is bent by contacting the case,
The power storage device, wherein a concave portion into which at least a part of the bent first rib enters is formed on the facing surface.   The power storage device according to claim 1, wherein a gap is formed between the concave portion and the bent first rib in the stacking direction. The dimensions of the recess in the front Symbol stacking direction is t1, the first rib is a dimension of the root portion of the first rib in a state not in contact with the said casing, from the facing surface of the first 3. The power storage device according to claim 2, wherein the following condition is satisfied when a maximum dimension in a direction orthogonal to a direction in which the rib protrudes is t <b> 2.
t1> t2
The case includes at least a pair of first case side surfaces facing each other, a second case side surface extending in a direction orthogonal to the first case side surfaces and facing each other, and the adjacent first case side surfaces. And an R-shaped corner connecting the side surface of the second case,
The power storage device according to claim 1, wherein the first rib contacts at least the corner.   The opposing surfaces are a plurality of second ribs positioned in the refrigerant passage and extending in the passage direction of the refrigerant passage, wherein the plurality of the ribs are in contact with only the first case side surface of the case. The power storage device according to claim 4, wherein a second rib is formed.   The power storage device according to claim 1, wherein the spacer is a resin. A spacer used in a power storage device in which a stacked body in which a power storage element that houses a power generation element in a case and a spacer are alternately stacked is constrained in a stacking direction by a restraining member,
An opposing surface facing the adjacent power storage element, and a first rib forming a refrigerant passage for the refrigerant flowing along the opposing surface,
The first rib is bent by contacting the case,
The spacer is characterized in that a concave portion into which at least a part of the bent first rib enters is formed on the facing surface.

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