JP2020035692A - battery - Google Patents

Abstract

To provide a battery capable of suppressing variation in performance of a plurality of battery elements.SOLUTION: A battery 1 comprises: a plurality of battery elements 10; a case body 20 which has an opening 20a on its one end side and is internally provided with a plurality of housing parts 24 for housing the plurality of battery elements 10; a lid 25 for closing the opening 20a of the case body 20; and a plurality of discharge valves 30 which are provided on the lid 25 so as to discharge gas in the housing parts 24 if pressure inside the housing parts 24 becomes equal to or higher than a predetermined value. The case body 20 has a bottom 21 facing the lid 25 and is provided to extend in the longitudinal direction. The volume of each of the discharge valves 30B arranged in a center portion in the longitudinal direction is greater than the volume of each of the discharge valves 30A arranged at both ends in the longitudinal direction. Alternatively, an inner surface of the lid in the center portion is located further on the bottom side than the inner surface of the lid at both ends.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to batteries, and more particularly, to batteries mounted on vehicles.

  DESCRIPTION OF RELATED ART Conventionally, as described in Unexamined-Japanese-Patent No. 2012-227099 (patent document 1), the battery in which the battery element (power generation element) was accommodated in each of several accommodating parts divided by the several partition in a case body is known. Have been.

JP 2012-227099 A

  However, when the battery element is housed in each of the plurality of housing sections as described above, hydrogen generated by the battery element is released to the outside of the case body at both ends of the case body and at the center of the case body. The release rate is different. Specifically, the release speed of both ends of the case body is faster than that of the central part of the case body. For this reason, it has been difficult to make the amount of hydrogen stored in the storage units located at both ends and the amount of hydrogen stored in the storage units located in the center uniform. In this case, the performance of the plurality of battery elements varies.

  The present disclosure has been made in view of the above-described problems, and an object of the present disclosure is to provide a battery that can suppress variations in performance of a plurality of battery elements.

  A battery according to an embodiment of the present disclosure includes a plurality of battery elements, a case body provided with an opening on one end side, and a plurality of housing portions for housing each of the plurality of battery elements provided therein, and the opening of the case body. A lid for closing the part, and a plurality of discharge valves provided on the lid so as to discharge gas in the storage part when the pressure of the storage part becomes a predetermined value or more. The case has a bottom facing the lid and is provided to extend in the longitudinal direction. At least in the accommodation portion, the volume of the discharge valve at the central portion in the longitudinal direction is larger than the volume of the discharge valve at both ends in the longitudinal direction, or the inner surface of the lid portion at the central portion has the both ends. Is located closer to the bottom than the inner surface of the lid.

  Generally, the amount of the gas generated by the battery element is released (leaked) from the housing portion, and the amount of the gas in the housing portion located at the center in the longitudinal direction is larger than the housing portions located at both ends in the longitudinal direction of the case body. Less.

  When the battery is configured as described above, and at least in the housing portion, the volume of the exhaust valve at the central portion in the longitudinal direction is larger than the volume of exhaust valves at both ends in the longitudinal direction, or the lid at the central portion. When the inner surface of the portion is located on the bottom side with respect to the inner surface of the lid portion at the both ends, the internal pressure of the accommodation portion arranged at the central portion in the longitudinal direction is arranged at both ends in the longitudinal direction. It can be higher than the internal pressure of the accommodated portion.

  For this reason, the amount of the gas released from the storage portion located at the central portion in the longitudinal direction can be increased. This makes it possible to equalize the amount of gas released from the storage section on both ends and the center side in the longitudinal direction, and to make the amount of gas stored in each storage section uniform. it can. As a result, variations in the performance of the plurality of battery elements can be suppressed.

  According to the present disclosure, it is possible to provide a battery that can suppress variations in performance of a plurality of battery elements.

FIG. 2 is a schematic sectional view of the battery according to the first embodiment. FIG. 7 is a schematic sectional view of a battery according to a second embodiment. FIG. 9 is a schematic sectional view of a battery according to a third embodiment. FIG. 9 is a schematic sectional view of a battery according to a fourth embodiment.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following embodiments, the same or common portions are denoted by the same reference numerals in the drawings, and description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a schematic sectional view of the battery according to the first embodiment. The battery 1 according to the first embodiment will be described with reference to FIG. The battery 1 is mounted on, for example, a hybrid vehicle, an electric vehicle, and a fuel cell vehicle, and can be used as a power source for these.

  As shown in FIG. 1, the battery 1 according to the first embodiment includes a plurality of battery elements 10, a case body 20, a lid 25, and a plurality of discharge valves 30.

  The plurality of battery elements 10 are housed in a plurality of housing portions 24 formed in the case body 20. The plurality of battery elements 10 are arranged in a row, for example.

  Battery element 10 includes a plurality of positive plates, a plurality of negative plates, and a plurality of separators. The battery element 10 is configured by stacking a positive electrode plate and a negative electrode plate with a separator interposed therebetween.

  The positive electrode plate has a plate shape. The positive electrode plate contains a positive electrode active material. As the positive electrode active material, for example, nickel hydroxide can be used. The positive electrode plate is formed by applying a paste mainly containing nickel hydroxide on a substrate.

  The negative electrode plate has a plate shape. The negative electrode plate contains a negative electrode active material. As the negative electrode active material, for example, a hydrogen storage alloy can be used. The negative electrode plate is formed by applying a paste mainly containing a hydrogen storage alloy on a substrate.

  As the substrate on which the positive electrode plate and the negative electrode plate are formed, for example, a porous conductive member can be used. As the porous conductive member, for example, a foamed nickel sheet can be used.

  The separator holds the electrolyte while preventing a short circuit between the positive electrode plate and the negative electrode plate. As the separator, a porous sheet having ion permeability and insulating properties is used. As the separator, for example, a polyolefin-based nonwoven fabric can be adopted. As the electrolyte, for example, an alkaline aqueous solution and a KOH aqueous solution generally used for a nickel-metal hydride battery can be employed.

  When the battery element 10 is formed, the positive electrode plate and the negative electrode plate are stacked while interposing a separator impregnated with an electrolyte beforehand. The electrolytic solution is preferably stored in the storage section 24 together with the battery element 10.

  In addition, the battery element 10 may be configured by alternately stacking a strip-shaped positive plate and a strip-shaped negative plate with a separator interposed therebetween, and winding this flat.

  The plurality of battery elements 10 are electrically connected in series. Specifically, the positive electrode plate has an uncoated portion on which the paste containing the positive electrode active material is not applied, and the negative electrode plate has an uncoated portion on which the paste containing the negative electrode active material is not applied.

  In the battery elements 10 adjacent to each other, an uncoated portion of the positive electrode plate of one battery element 10 and an uncoated portion of the negative electrode plate of the other battery element 10 are connected by a current collecting member.

  In the battery element 10 arranged at one end of the arranged plurality of battery elements 10, a current collecting member that is not connected to another battery element 10 is connected to the positive terminal 15 </ b> P provided on the case body 20. It is connected.

  In the battery element 10 arranged at the other end of the arranged plurality of battery elements 10, a current collecting member that is not connected to another battery element 10 is connected to the negative terminal 15 </ b> N provided on the case body 20. It is connected.

  The case body 20 has a box shape having an opening 20a provided at one end. The case body 20 is provided so as to extend in the longitudinal direction (the direction DR1 in FIG. 1). The longitudinal direction is parallel to the direction in which the battery elements 10 are arranged.

  The case body 20 has a bottom part 21, a peripheral wall part 22, and a plurality of partition parts 23. The bottom 21 is formed substantially flat. The bottom 21 is provided so as to face a lid 25 described later.

  The peripheral wall portion 22 is provided so as to rise from the peripheral edge of the bottom portion 21. The plurality of partition portions 23 are arranged side by side in the longitudinal direction. The plurality of partition portions 23 partition the inside of the case body 20 into a plurality of accommodation spaces. As a result, a housing portion 24 for housing each of the plurality of battery elements 10 is formed inside the case body 20. The plurality of housing portions 24 are formed independently of each other. The plurality of housing portions 24 are arranged along the longitudinal direction.

  The lid 25 has a flat plate shape. The cover 25 closes the opening 20 a provided in the case body 20. The lid 25 is provided with a plurality of discharge valves 30.

  The plurality of discharge valves 30 are provided so as to penetrate the lid 25. The plurality of discharge valves 30 are inserted into a plurality of through holes provided in the lid 25. The plurality of discharge valves 30 are provided in the lid 25 so as to discharge the gas in the storage unit 24 when the pressure in the storage unit 24 becomes equal to or higher than a predetermined value. The discharge valve 30 is provided for each storage unit 24. The plurality of discharge valves 30 are arranged side by side along the longitudinal direction.

  The plurality of discharge valves 30 are configured by rubber valves. The discharge valve 30 has a valve body 31, a connecting part 32, and an engaging part 33.

  The valve body 31 is disposed outside the lid 25. It is elastically pressed against the upper surface of the lid 25 located around the through hole provided in the lid 25. The connecting portion 32 extends from the valve body portion 31 so as to pass through the through hole. The connection part 32 connects the valve body part 31 and the engagement part 33. The engaging portion 33 engages with the lower surface of the lid portion 25 located around the through hole while the connecting portion 32 is elastically pulled. A groove 34 is provided on the upper surface of the engaging portion 33 and the peripheral surface of the connecting portion 32.

  When the internal pressure of the storage section 24 becomes equal to or higher than a predetermined value, the gas in the storage section 24 pushes up the valve body 31 through the groove. As a result, the outside of the lid 25 and the housing portion 24 communicate with each other through the groove portion 34, and as a result, gas in the housing portion 24 is discharged through the groove portion 34.

  The plurality of discharge valves 30 include a discharge valve 30A disposed at both ends in the longitudinal direction, and a discharge valve 30B disposed at a central portion in the longitudinal direction. The central portion in the longitudinal direction means between two discharge valves 30A located at both ends.

  In the first embodiment, the size of the discharge valve 30A and the size of the discharge valve 30B are different. Specifically, the discharge valve 30B is generally larger than the discharge valve 30A. That is, the volume of the discharge valve 30B is larger than the volume of the discharge valve 30A as a whole.

  Here, the case body 20 and the lid 25 can be made of a resin member. As the resin material, polypropylene (PP) alone, a polymer alloy of polystyrene (PS) and polyphenylene ether (PPE), a polymer alloy of polypropylene (PP) and polyphenylene ether (PPE), and the like are used.

  The resin material is suitable for molding the case body 20 and the lid 25 because it is easy to mold and process. On the other hand, the gas that the battery element 10 in the housing part 24 absorbs and discharges as it charges and discharges passes. Specifically, hydrogen permeates, and hydrogen stored in each storage unit 24 leaks.

  Generally, when a plurality of battery elements 10 are arranged along the longitudinal direction of the case body 20 as described above, the amount of leakage from the housing portions 24 located at both ends in the longitudinal direction is limited to the central portion in the longitudinal direction. , The amount of leakage from the storage section 24 located at the position. In such a case, the amount of hydrogen stored in the accommodating portion 24 varies at both ends in the longitudinal direction and at the center. For this reason, the performance of the plurality of battery elements may vary.

  Here, in the battery 1 according to the first embodiment, as described above, the volume of the discharge valve 30B disposed at the center in the longitudinal direction is generally equal to the discharge valve 30B disposed at both ends in the longitudinal direction. It is larger than the volume of the valve 30A.

  For this reason, the internal pressure of the accommodation portions 24 arranged at the center in the longitudinal direction can be made higher than the internal pressure of the accommodation portions 24 arranged at both ends in the longitudinal direction. This makes it possible to increase the amount of the gas released from the storage portion located at the central portion in the longitudinal direction, and to increase the amount of the gas released from the storage portion at both ends and the central portion in the longitudinal direction. The amount can be uniform. As a result, the amount of the gas stored in each storage unit can be made uniform, and variations in the performance of a plurality of battery elements can be suppressed.

  In the first embodiment, the case where the volume of the discharge valve 30B is larger than that of the discharge valve 30A is described as an example, but the present invention is not limited to this. It is sufficient that the volume of the discharge valve 30B is larger than the volume of the discharge valve 30A in at least the housing portion 24.

(Embodiment 2)
FIG. 2 is a schematic sectional view of the battery according to the second embodiment. A battery 1A according to Embodiment 2 will be described with reference to FIG.

  As shown in FIG. 2, the battery 1A according to the second embodiment differs from the battery 1 according to the first embodiment in the configuration of the discharge valve 30B. Other configurations are almost the same.

  The discharge valve 30 </ b> B according to the second embodiment has a shorter length in the vertical direction perpendicular to the opening surface of the case body 20 than the discharge valve 30 </ b> B according to the first embodiment. The width along the direction (DR1 direction in FIG. 2) is wide. Even in such a case, substantially the same effects as in the first embodiment can be obtained.

(Embodiment 3)
FIG. 3 is a schematic sectional view of the battery according to the third embodiment. A battery 1B according to Embodiment 3 will be described with reference to FIG.

  As shown in FIG. 3, the battery 1B according to the second embodiment is different from the battery 1 according to the first embodiment in the configuration of the plurality of discharge valves 30 and the configuration of the lid 25B. Other configurations are almost the same.

  In battery 1B according to Embodiment 3, all the plurality of discharge valves 30 are formed in the same shape and size. For this reason, the manufacturing cost of the discharge valve 30 can be reduced.

  In the longitudinal direction of the case body 20 (the DR1 direction in FIG. 3), the central portion of the lid 25B is recessed in a direction closer to the bottom 21 of the case body 20 than both ends of the lid 25B in the longitudinal direction. Thus, the inner surface of the lid 25B at the center is located closer to the bottom 21 of the case body 20 than the inner surfaces of the lids 25B at both ends. The thickness of the lid 25B at the center in the longitudinal direction is substantially equal to the thickness of the lid 25B at both ends in the longitudinal direction.

  Also in this case, the internal pressure of the housing portions 24 arranged at the center in the longitudinal direction can be made higher than the internal pressure of the housing portions 24 arranged at both ends in the longitudinal direction. This makes it possible to increase the amount of the gas released from the storage portion located at the central portion in the longitudinal direction, and to increase the amount of the gas released from the storage portion at both ends and the central portion in the longitudinal direction. The amount can be uniform. As a result, the amount of the gas stored in each storage unit can be made uniform, and variations in the performance of a plurality of battery elements can be suppressed.

  In the third embodiment, the case where the center of the lid 25B in the longitudinal direction is recessed from both ends of the lid 25B in the longitudinal direction has been described as an example, but the present invention is not limited to this. The central portion of the lid 25B may be formed such that the thickness increases toward the bottom 21 of the case body 20 from both ends of the lid 25B. In this case, two types of discharge valves are provided at the center and both ends in the longitudinal direction according to the thickness.

(Embodiment 4)
FIG. 4 is a schematic sectional view of the battery according to the fourth embodiment. Referring to FIG. 4, a battery 1C according to Embodiment 4 will be described.

  As shown in FIG. 4, the battery 1C according to the fourth embodiment is different from the battery 1 according to the first embodiment in the configuration of the plurality of discharge valves 30 and the configuration of the lid 25C. Other configurations are almost the same.

  In battery 1C according to Embodiment 4, a plurality of discharge valves 30 are all formed in the same shape and size. For this reason, the manufacturing cost of the discharge valve 30 can be reduced.

  In the longitudinal direction of the case body 20 (the direction DR1 in FIG. 2), both ends of the cover 25C protrude in a direction away from the case body 20 than the center of the cover 25C in the longitudinal direction. Thus, the inner surface of the lid 25C at the center is located closer to the bottom 21 of the case body 20 than the inner surfaces of the lids 25C at both ends. The thickness of the lid 25C at the center in the longitudinal direction is substantially equal to the thickness of the lid 25C at both ends in the longitudinal direction.

  In this case, the internal pressure of the housing portions 24 arranged at both ends in the longitudinal direction is reduced. For this reason, the internal pressure of the accommodation portions 24 arranged at the center in the longitudinal direction can be made higher than the internal pressure of the accommodation portions 24 arranged at both ends in the longitudinal direction. This makes it possible to increase the amount of the gas released from the storage portion located at the central portion in the longitudinal direction, and to increase the amount of the gas released from the storage portion at both ends and the central portion in the longitudinal direction. The amount can be uniform. As a result, the amount of the gas stored in each storage unit can be made uniform, and variations in the performance of a plurality of battery elements can be suppressed.

  In the fourth embodiment, the case where both ends of the lid portion 25C in the longitudinal direction protrude in a direction away from the bottom portion 21 from the central portion of the lid portion 25C in the longitudinal direction has been described as an example. It is not limited to. Both ends of the lid 25C in the longitudinal direction may be formed so as to be thinner than the center of the lid 25C. In this case, two types of discharge valves are provided at the center and both ends in the longitudinal direction according to the thickness.

  As described above, the embodiments disclosed this time are illustrative in all aspects and are not restrictive. The scope of the present invention is defined by the appended claims, and includes all modifications within the scope and meaning equivalent to the claims.

  1, 1A, 1B, 1C battery, 10 battery element, 15N negative electrode terminal, 15P positive electrode terminal, 20 case body, 20a opening, 21 bottom, 22 peripheral wall, 23 partition, 24 housing, 25, 25B, 25C lid Parts, 30, 30A, 30B discharge valve, 31 valve body part, 32 connecting part, 33 engaging part, 34 groove part.

Claims (1)

A plurality of battery elements,
A case body provided with an opening on one end side, and a plurality of housing portions for housing each of the plurality of battery elements provided therein;
A lid for closing the opening of the case body,
A plurality of discharge valves provided in the lid portion, so as to discharge gas in the storage portion when the pressure of the storage portion is equal to or more than a predetermined value,
The case body has a bottom facing the lid, and is provided to extend in the longitudinal direction,
At least in the housing portion, the volume of the discharge valve disposed at the central portion in the longitudinal direction is larger than the volume of the discharge valve disposed at both ends in the longitudinal direction.
Alternatively, a battery wherein the inner surface of the lid at the center is located closer to the bottom than the inner surfaces of the lid at the ends.

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