JP2014232598A - Heat dissipation structure of power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat dissipation structure of a power storage device capable of suppressing temperature rising of a secondary battery housed in a case within the power storage device and minimizing a temperature difference of the secondary battery in an array direction.SOLUTION: In the power storage device, a plurality of columnar secondary batteries 2 are arrayed and housed within a case 1 while making axial lines parallel with each other. In the case 1, a side opening 3 is formed on a sidewall 8 closer to both end portion in an array direction orthogonal to the axial lines of the secondary batteries 2, and a center opening 4 is formed on a top plate 10 or a bottom plate 9 which is positioned in a central portion in the array direction. Suction means 5 is provided at one side of the side opening 3 or the center opening 4, and the other side is defined as an air inflow port.

Description

  The present invention relates to a heat dissipation structure for a power storage device using a secondary battery.

  In recent years, interest in energy management has increased due to consideration of the global environment and the problem of power supply triggered by a major earthquake. In this energy management, a power storage device is indispensable.

  This power storage device has a wide range of uses such as peak shift of surplus power, power leveling of natural energy that is easily affected by weather such as sunlight and wind power, and emergency power supply for servers. The power storage device connects a plurality of secondary batteries in series and parallel, and performs charging and discharging as necessary, and generates heat when the secondary battery performs charging and discharging.

  By the way, in the said electrical storage apparatus, in consideration of size reduction of an electrical storage apparatus, it is necessary to arrange | position many cylindrical secondary batteries at high density. On the other hand, at the time of charging and discharging, the secondary battery generates heat and becomes high temperature. This secondary battery has a characteristic that the life is shortened at a high temperature range, or the charging efficiency is lowered or the battery cannot be discharged. Therefore, a power storage device that can stably exhibit battery characteristics is required.

  Therefore, as shown in FIGS. 5 to 6, a conventional case 100 used in a power storage device includes a plurality of cylindrical secondary batteries 20 arranged in parallel with each other in parallel with each other in the case 100. In addition, side openings 30 are formed in the side walls 40 at both ends in the arrangement direction orthogonal to the axis, and a suction fan 50 is provided on one side of the side openings 30, and the other side is an air inlet. Has been. In this conventional case 100, a plurality of rows of secondary batteries 20 are arranged with partition plates 80 extending in the arrangement direction perpendicular to the axis of the secondary batteries 20 therebetween.

  In this conventional case 100, the air in the case 100 is sucked by the operation of the suction fan 50 provided on one side of the side opening 30, and the air inlet of the other side opening 30. Outside air flows in from the air, and the air that has further flowed in is discharged to the outside by suction of the suction fan 50. Thus, the secondary battery 20 that generates heat during charging or discharging is cooled by the cold air flowing in from the air inlet.

  However, in the conventional heat dissipation structure, the cold air flowing in from the air inlet by the suction of the suction fan 50 is circulated from the upstream side to the downstream side along the arrangement direction of the secondary batteries 20 to generate heat. Heating by the secondary battery 20 reduces the cooling efficiency. For this reason, as shown in the thermal analysis result performed by the inventor of FIG. 7A, a temperature difference of the secondary batteries 20 occurs in the arrangement direction.

  In addition, the thermal analysis result of FIG. 7 (a) is obtained by arranging 18 secondary batteries having a diameter of 17.8 mm in parallel with their axis lines in a case having a width dimension of 46 cm and a height dimension of 3.6 cm. This is a two-dimensional analysis by calculating a steady-state temperature distribution when applying constant heat to the secondary battery in the case and applying a suction speed of 1 m / sec in the direction of t. The environmental temperature is 25 ° C.

  Therefore, in Patent Document 1 below, a turbulent flow promoting body is provided at the upstream position of the battery unit disposed on the most upstream side of the flow path, with the periphery of the battery unit as a flow path for the refrigerant along the arrangement direction. To improve the cooling capacity by increasing the heat transfer coefficient.

Japanese Patent No. 11-329518

However, the conventional power storage device is effective when the number of secondary batteries is small with respect to the arrangement direction in which the refrigerant flows, but the number of secondary batteries in the case-type power storage device is also large. In many cases, in the process in which the refrigerant flows along the arrangement direction, the secondary battery that has generated heat is heated and the cooling capacity is reduced.
In particular, when the secondary battery has a cylindrical shape, this tendency appears remarkably because the thermal conductivity between the secondary batteries is poor.

  The present invention has been made in view of such circumstances, and suppresses the temperature rise of the secondary batteries housed in the case in the power storage device and minimizes the temperature difference between the secondary batteries in the arrangement direction. It is an object of the present invention to provide a heat dissipation structure for a power storage device that can be used.

  In order to solve the above-described problem, the invention described in claim 1 is a power storage device in which a plurality of cylindrical secondary batteries are housed in a case in which a plurality of axes are arranged in parallel with each other. A side opening is formed on the side walls on both ends in the arrangement direction orthogonal to the axis of the secondary battery, and a central opening is formed on the top plate or the bottom plate located in the central portion of the arrangement direction. A suction means is provided on one side of the side opening or the central opening, and the other side is an air inflow port.

  The invention according to claim 2 is the invention according to claim 1, wherein the case includes a plurality of partition plates in which the secondary battery extends in the arrangement direction perpendicular to the axis of the secondary battery. A plurality of rows are accommodated therebetween, and the side opening and the central opening are formed for each row.

  According to this invention of Claim 1-2, when the air which flowed in from the air inflow port is discharged | emitted outside along the said arrangement direction via the said suction means, it forms in the said arrangement direction Since the distance of the flow path is about half that of the conventional one, even if the air is heated by the secondary battery that generates heat when the power storage device is charged and discharged, the air becomes high temperature. It can be discharged to the outside before. As a result, a decrease in cooling efficiency of the air flowing along the arrangement direction is suppressed, the secondary batteries can be radiated efficiently, and the temperature difference of the secondary batteries in the arrangement direction is minimized. can do. Furthermore, the difference in the life and charging efficiency of each secondary battery can be suppressed, and the characteristics of the device itself can be improved.

  According to the second aspect of the present invention, even when the number of the secondary batteries is increased and stored in a plurality of rows, the air flowing in from the air inlet for each row is not charged when the power storage device is charged. In addition, before being heated to a high temperature by the secondary battery that generates heat during discharge, it can be discharged to the outside along the flow path, which is about half the distance from the conventional one. As a result, a decrease in cooling efficiency of the air flowing along the arrangement direction is suppressed, and the secondary batteries can be efficiently dissipated, and the temperature difference between the secondary batteries in the arrangement direction is minimized. can do. Furthermore, the difference in the life and charging efficiency of each secondary battery can be suppressed, and the characteristics of the device itself can be improved.

The case used for the electrical storage apparatus of one Embodiment of this invention is shown, (a) is sectional drawing, (b) is a cross-sectional perspective view of (a). It is a perspective view of a case in the state where a top plate used for a power storage device of one embodiment of the present invention was removed. It is the schematic which shows the flow of the air of the case used for the electrical storage apparatus of one Embodiment of this invention. It is the schematic which shows the flow of the air of the case used for the electrical storage apparatus of the modification of one Embodiment of this invention. The case used for the conventional electrical storage apparatus is shown, (a) is sectional drawing, (b) is a cross-sectional perspective view of (a). It is a perspective view of the case of the state which removed the top plate used for the conventional electrical storage apparatus. The thermal analysis result of the secondary battery which added heat | fever is shown, (a) is the temperature distribution of the conventional structure of FIG.5 and FIG.6, (b) is the temperature distribution by the structure of this invention.

  1 to 3 show an embodiment of a heat dissipation structure for a power storage device according to the present invention. A case 1 used in this power storage device includes a plurality of secondary batteries 2 arranged in parallel with each other in the axis. The side opening 3 is formed in the side wall 8 at both ends of the secondary battery 2 in the arrangement direction, and the central opening 4 is formed in the bottom plate 9 in the central part in the arrangement direction. A suction fan (suction means) 5 is provided in the opening 4.

  Here, the secondary battery 2 has a cylindrical shape, and a plurality of gaps 6 are formed in the central portion in the arrangement direction orthogonal to the axis, and the secondary batteries 2 are stacked (two layers in the figure). ) And stored in the case 1.

  In addition, the case 1 is formed in a square shape from an alloy or the like, for example, and the lid portion forms the top plate 10. In the case 1, a plurality of (seven in the figure) partition plates 7 extending in the arrangement direction perpendicular to the axis of the secondary battery 2 are provided at equal intervals. The partition plate 7 is formed to have substantially the same length as the length of the secondary battery 2 in the arrangement direction, and to the same height as the height of the side wall 8 of the case 1. Has been.

  A plurality of secondary batteries 2 arranged in parallel with each other in axis are accommodated in a plurality of rows (six rows in the figure) with a partition plate 7 interposed therebetween. Further, side openings 3 are formed in the side walls 8 on both end sides in the arrangement direction orthogonal to the axis of each secondary battery 2 housed in each row.

  The side opening 3 serves as an air inflow port for taking in outside air by suction of the suction fan 5. In addition, the side openings 3 are formed with a plurality (three in the figure) of rectangular openings at intervals in the height direction of the side walls 8 in order to prevent foreign substances from entering from the outside.

  Further, a central opening 4 is formed in the bottom plate 9 located in the gap 6 in the central portion in the arrangement direction of the secondary batteries 2 housed in each row. The central opening 4 is opened in a substantially square shape, and a suction fan 5 is provided in the central opening 4.

  Then, for example, as shown in FIG. 3, the case 1 is stacked in a plurality of stages (four stages in the figure), and a plurality of secondary batteries 2 are connected in series and parallel and arranged in the power storage device. Will be.

  In order to dissipate heat from the secondary battery 2 that has generated heat during charging or discharging using the heat dissipation structure of the power storage device having the above configuration, first, the secondary battery 2 housed in the case 1 of the power storage device is charged or discharged. To do. As a result, the secondary battery 2 generates heat. For example, the suction fan 5 provided in the central opening 4 of the bottom plate 9 of the case 1 is operated by detecting the generated heat by a sensor or the like.

  Next, as shown in FIG. 3, air is sucked from the central opening 4 of the bottom plate 9 by the operation of the suction fan 5, and outside air from each air inlet of the side opening 3 of the side wall 8 of the case 1. Flows in. The inflowing air flows along the arrangement direction of the secondary batteries 2 and is discharged from the central opening 4 provided with the suction fan 5 while cooling the secondary batteries 2 that have generated heat.

  At this time, since the central opening 4 through which the air is discharged through the suction fan 5 is formed in the central portion of the secondary battery 2 in the arrangement direction, the central opening 4 is interposed therebetween. A flow path in two directions is formed along the arrangement direction. Since the distance of each of the flow paths is about half the distance of the flow paths formed along the arrangement direction of the conventional secondary battery 2, the air flowing in from each of the air inlets is recharged. Before being heated to a high temperature by the battery 2, it is discharged to the outside from the central opening 4.

  Therefore, in the arrangement direction of the secondary batteries 2, a temperature difference set between the air that has flowed in from the air inlet and the secondary battery 2 that has generated heat is generated. The secondary battery 2 can be cooled. As a result, the temperature difference between the secondary batteries 2 in the arrangement direction can be minimized.

Here, the heat dissipation effect of the secondary battery 2 will be described based on the calculation performed by the inventor of FIG.
In addition, the thermal analysis result of FIG.7 (b) is the case where 18 axis | shafts of 17.8 mm in diameter are arranged in parallel with each other in the case of a width dimension of 46 cm, and a height dimension of 3.6 cm. This is a two-dimensional analysis by calculating a steady-state temperature distribution when a constant heat is applied to the secondary battery in the case and a suction speed of 1 m / sec is applied in the t direction. The environmental temperature is 25 ° C.

As shown in the thermal analysis result of FIG. 7B, by sucking from the gap in the central portion in the arrangement direction of the secondary batteries 2, the inflowing air is suppressed from decreasing in cooling efficiency, and from the central portion. Since it is discharged, it has been found that the temperature difference between the secondary batteries 2 in the arrangement direction is minimized.
Therefore, it is clear that the temperature difference between the secondary batteries 2 in the arrangement direction is minimized by using the heat dissipation structure of the power storage device of the present invention.

  Further, as shown in FIG. 4, in the modification of the embodiment of the heat dissipation structure for the power storage device according to the present invention, the top plate 10 of the case 1 located at the central portion in the arrangement direction of the secondary batteries 2 A central opening 4 is formed, an exhaust part 11 having an opening on the side wall 8 side of the case 1 is provided above the central opening 4, and a suction fan 5 is provided in the opening of the exhaust part 11. Each is provided.

  In this modification, air is introduced from the air inlet of the side opening 3 of the side wall 8 by being sucked by the suction fan 5 provided in the opening. The inflowed air flows along the arrangement direction of the secondary batteries 2, and is discharged to the outside from each opening provided with the suction fan 5 through the exhaust opening 11 from the central opening 4. become.

  Therefore, also in this modified example, in the arrangement direction of the secondary batteries 2, similarly to the above-described embodiment, the temperature set in the air that has flowed in from the air inlet and the secondary battery 2 that has generated heat in the arrangement direction of the secondary batteries 2. Since a difference arises, the fall of cooling efficiency is suppressed and the secondary battery 2 can be cooled. As a result, the temperature difference between the secondary batteries 2 in the arrangement direction can be minimized.

  According to the heat dissipation structure of the power storage device having the above configuration, when the air flowing in from the air inflow port is discharged to the outside along the arrangement direction via the suction fan 5, it is formed in the arrangement direction. Since the distance of the flow path is about half that of the conventional one, even when the air is heated by the secondary battery 2 that generates heat when the power storage device is charged and discharged, the air becomes high temperature. It can be discharged to the outside before. As a result, a decrease in cooling efficiency of the air flowing along the arrangement direction is suppressed, the secondary batteries 2 can be efficiently radiated, and the temperature difference of the secondary batteries 2 in the arrangement direction is minimized. can do. Furthermore, the difference in the life and charging efficiency of each secondary battery 2 is suppressed, and the characteristics of the device itself can be improved.

  Further, even when the number of secondary batteries 2 is increased and stored in a plurality of rows, the secondary battery 2 in which air flowing from the air inlet for each row generates heat during charging and discharging of the power storage device. Before being heated to a high temperature by the above, it can be discharged to the outside along the above-mentioned flow path that is about half the distance compared to the conventional case. As a result, a decrease in cooling efficiency of the air flowing along the arrangement direction is suppressed, the secondary batteries 2 can be efficiently radiated, and the temperature difference of the secondary batteries 2 in the arrangement direction is minimized. can do. Furthermore, the difference in the life and charging efficiency of each secondary battery 2 is suppressed, and the characteristics of the device itself can be improved.

  Furthermore, a plurality of secondary batteries 2 are arranged in a central portion in the arrangement direction perpendicular to the axis of the secondary battery 2 with a gap 6 formed therein, and housed in the case 1. Since the sucked air causes convection in the space of the gap 6, the heat dissipation efficiency of the secondary battery 2 can be promoted.

  In the above embodiment, only the method of suction using the suction fan 5 from the central opening 4 formed in the top plate 10 or the bottom plate 9 of the case 1 has been described, but the present invention is not limited to this. Alternatively, suction may be provided by providing a suction fan 5 in the side opening 3 formed in the side wall 8 of the case 1. In that case, the suction fans 5 are provided in the side openings 3 of the side walls 8 at both ends in the arrangement direction of the secondary batteries 2.

  It can be used for a power storage device using a secondary battery.

DESCRIPTION OF SYMBOLS 1 Case 2 Secondary battery 3 Side part opening part 4 Center opening part 5 Fan (suction means)
6 Gap 7 Partition plate 8 Side wall 9 Bottom plate 10 Top plate

Claims (2)

In a power storage device in which a plurality of cylindrical secondary batteries are arranged and stored in parallel with each other in the case,
In the case, side openings are formed in side walls on both end sides in the arrangement direction orthogonal to the axis of the secondary battery, and a central opening is formed in a top plate or a bottom plate located in a central portion in the arrangement direction. A heat dissipation structure for a power storage device, which is formed and has suction means provided on one side of the side opening or the central opening and the other side is an air inlet.   In the case, the secondary battery is accommodated in a plurality of rows with a plurality of partition plates extending in the arrangement direction orthogonal to the axis of the secondary battery therebetween, and the side opening is provided for each row. 2. The heat dissipation structure for a power storage device according to claim 1, wherein a portion and a central opening are formed.

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