JP6519443B2 - Battery pack - Google Patents

Description

  The present invention relates to a battery pack having a plurality of battery cells housed in a case.

  As a conventional battery pack, for example, the one described in Patent Document 1 is known. The battery pack described in Patent Document 1 is a control device for a fan that cools a vehicle-mounted battery. The on-board battery supplies power to the electric motor serving as a driving source for traveling, and is disposed, for example, under a seat for a passenger. Further, at a position adjacent to the on-board battery, a fan for cooling the on-board battery is provided. The operation of the fan is controlled by the controller. The air-conditioned air in the vehicle compartment is supplied to the on-vehicle battery by the operation of the fan.

  And in patent document 1, when the temperature of a vehicle-mounted battery becomes more than predetermined A level, a control apparatus operates a fan and cools a vehicle-mounted battery. At this time, in Patent Document 1, as the battery temperature increases (increases to A to E), and as the noise level in the passenger compartment increases (increase to 1 to 3), the rotational speed of the fan increases. It is controlled to be large.

  Thereby, it is possible to effectively cool the on-vehicle battery while reducing the sensational noise caused by the operation noise of the fan.

Patent No. 3843956

  In Patent Document 1, as described above, the in-vehicle battery and the fan are disposed under the seat which is an open space in the vehicle compartment, and the fan is operated when the temperature of the in-vehicle battery is A level or more. By supplying conditioned air in the room to the onboard battery, effective cooling is possible. That is, Patent Document 1 is an open air-cooled battery pack. On the other hand, control of the rotational speed of the fan according to the noise level in the passenger compartment is incorporated, since the operation sound of the fan can be directly heard by the occupant.

  Here, the present inventors consider a sealed battery pack in which a plurality of battery cells and a blower are accommodated in a housing, and the temperature of the plurality of battery cells is controlled by circulating a cooling fluid in the housing by a blower. doing. In such a sealed battery pack, since the blower is accommodated in the housing, the influence of the operation noise of the blower on the occupant can be suppressed.

  However, in the closed battery pack, the heat of the battery cells is transferred to the cooling fluid in the housing, the wall of the housing, and the air outside the housing in this order. Therefore, heat transfer takes time for the closed type battery pack compared to the case where the heat of the battery cell is directly released to the external air (air conditioning air) of the housing as in the open type battery pack, and In temperature management based on temperature, for example, there is a problem that the response is poor such that an overshoot occurs with respect to the control temperature.

  The present invention has been made in view of the above problems, and provides a battery pack capable of improving responsiveness regarding temperature control of battery cells in a case where a plurality of battery cells and a blower are accommodated in a housing. It is.

  The present invention adopts the following technical means to achieve the above object.

In the present invention, a plurality of batteries (121),
A housing (110) for housing a plurality of batteries (121);
A circulation passage (130) formed in the housing (110) and in which the heat exchange fluid flows so as to contact the plurality of batteries (121) and the inner wall surfaces of the housing (110);
A blower (140) housed in the housing (110) and circulating fluid through the circulation passage (130);
A control unit (190) for controlling the operation of the blower (140);
A calculation unit (193) for calculating a calorific value of a predetermined battery (121) among the plurality of batteries (121);
A detector (183) for detecting the temperature of a predetermined battery (121);
The control unit (190) is configured to determine the number of rotations of the fan (140) based on the calorific value obtained by the calculation unit (193),
The control unit (190) instructs the fan (140) to operate at the first rotation speed based on the calorific value as the first operating condition for the fan (140) to be turned on from the off state, and generates heat after the operation The blower (140) is operated and controlled under the condition of the larger one of the first number of revolutions based on the amount and the second number of revolutions based on the temperature obtained by the detector (183). There is.

  According to the present invention, the number of rotations of the blower (140) is controlled based on the amount of heat generation of the battery (121). Since temperature control using the calorific value of the battery (121) is feedforward control based on a factor system related to the temperature change of the battery (121), prospective control becomes possible in anticipation of the temperature, and as a result system Temperature overshoot or the like in feedback control used can be suppressed to improve responsiveness regarding temperature management.

  The reference numerals in parentheses in the claims are intended to limit the contents of the invention, for the purpose of restricting the contents of the invention, for the purpose of facilitating the understanding of the contents of the description and for illustrating the corresponding configuration in the embodiments described later. Absent.

It is a top view which shows the structure of the battery pack in 1st Embodiment. It is sectional drawing which shows the II-II part in FIG. It is sectional drawing which shows the III-III part in FIG. It is sectional drawing which shows the IV-IV part in FIG. It is an exploded perspective view showing an internal fin. It is a perspective view showing an external fin. It is a perspective view showing an external duct. It is explanatory drawing which shows the structure of the battery management unit in 1st Embodiment. It is a graph which shows the current to a lapse of time, and a cell voltage. It is a graph (1st map) which shows the rotation speed with respect to cell emitted-heat amount. It is a top view which shows the flow of the fluid in a case. It is a side view showing the flow of the fluid in a case. It is a perspective view which shows the flow of the fluid by the internal fin in a case. FIG. 7 is a perspective view showing the flow of fluid in the outer duct. It is a graph which shows cell emitted-heat amount with respect to time progress, cell temperature, and rotation speed. It is explanatory drawing which shows the structure of the battery management unit in 2nd Embodiment. It is a graph (2nd map) which shows the rotation speed with respect to cell temperature. It is explanatory drawing which shows the structure of the battery management unit in the modification of 2nd Embodiment. It is a table | surface (3rd map) which shows cell calorific value and the rotation speed with respect to cell temperature. It is explanatory drawing which shows the structure of the battery management unit in 3rd Embodiment. It is a graph (correction coefficient map) which shows the correction coefficient with respect to cell internal resistance. It is a graph which shows the correction procedure of basic rotation speed based on a correction coefficient.

  Hereinafter, a plurality of modes for carrying out the present invention will be described with reference to the drawings. The same referential mark may be attached | subjected to the part corresponding to the matter demonstrated by the form preceded in each form, and the overlapping description may be abbreviate | omitted. When only a part of the configuration is described in each form, the other forms described above can be applied to other parts of the configuration. Not only combinations of parts which clearly indicate that combinations are possible in each embodiment, but also combinations of embodiments even if not explicitly specified, unless any problem occurs in the combinations. It is also possible.

First Embodiment
The configuration of the battery pack 100 according to the first embodiment, which is an example of the present invention, will be described with reference to FIGS. 1 to 8. The battery pack 100 is used, for example, in a hybrid vehicle that uses a motor driven by electric power charged in a battery and an internal combustion engine as a traveling drive source, or in an electric vehicle that uses a motor as a traveling drive source. The plurality of battery cells 121 included in the battery pack 100 are, for example, a nickel-hydrogen secondary battery, a lithium ion secondary battery, an organic radical battery, and the like.

  Battery pack 100 is installed in a pack storage space such as a trunk room of a vehicle or a trunk room back area provided below the trunk room. The pack accommodation space can also accommodate, for example, a spare tire, a tool, and the like. The battery pack 100 is installed in the pack storage space in a posture in which the bottom wall 112 and the bottom wall side passage 135 described later are directed downward.

  Also, the battery pack 100 may be installed below the front seat or the rear seat provided in the cabin of the vehicle. In this case, the battery pack 100 is installed below the front seat, the rear seat, etc., with the bottom wall 112 and the bottom wall passage 135 facing downward. In addition, the space where the battery pack 100 is installed below the rear seat may be in communication with the rear trunk room area below the trunk room. The installation space can also be configured to communicate with the outside of the vehicle.

  The battery pack 100 includes a case 110, a battery assembly 120 (cell laminate 120A) including a plurality of battery cells 121, a circulation passage 130, a blower 140 (140A, 140B) provided with a PTC heater 144, and internal fins 150 (151). 152), an external fin 160 (161, 162), an external duct 170 having a blower 172, a voltage sensor 181, a current sensor 182, a temperature sensor 183, a battery management unit 190, and the like.

  In the present embodiment, in FIG. 1, Fr indicates the front side of the vehicle, Rr indicates the rear side of the vehicle, LH indicates the left side of the vehicle, and RH indicates the right side of the vehicle. When showing the direction in the battery pack 100, the direction of Fr-Rr is called the front-back direction, and the direction of LH-RH is called the left-right direction. Also, the direction of action of gravity is referred to as the vertical direction.

  The case 110 is a housing forming a sealed internal space isolated from the outside, and the battery assembly 120 and the blower 140 (140A, 140B), and further, the internal fin 150, the voltage sensor 181, the current sensor 182, and The battery management unit 190 and the like are accommodated inside.

  The case 110 is in the form of a box made of a plurality of walls surrounding an internal space, and is formed of a molded product of an aluminum plate or an iron plate. The case 110 is, for example, a flat rectangular parallelepiped in the vertical direction, and has six sides, that is, a top wall 111, a bottom wall 112, a side wall 113, a side wall 114, a side wall 115, and a side wall 116. In addition, the case 110 has a partition wall 117 that defines the inside, and a reinforcing beam 118 at the bottom wall 112.

  The top wall 111 is a wall that forms the upper surface of the case 110, and is a rectangular wall having a long side in the front-rear direction. The bottom wall 112 is a wall that forms the lower surface of the case 110, and has the same shape as the top wall 111.

  The side walls 113 and 114 are walls forming the left and right sides of the case 110, and are long and thin rectangular walls having long sides in the front-rear direction. The side walls 113 and 114 are in a positional relationship facing each other. Further, the side walls 115 and 116 are walls forming the front and rear sides of the case 110, and are long and thin rectangular walls having long sides in the left-right direction. Sidewalls 115 and 116 are in a positional relationship facing each other. Further, the side walls 115 and 116 are walls orthogonal to the side walls 113 and 114.

  The case 110 may be manufactured by forming a box-like space inside by joining and assembling a plurality of case bodies instead of using the walls 111 to 116 described above. Further, among the plurality of walls of the case 110, a plurality of projections or recesses may be formed on the surface of a predetermined wall in order to increase the heat dissipation area.

  In the battery pack 100, the direction along the long sides of the side walls 113 and 114 corresponds to the front-rear direction, and the direction along the long sides of the side walls 115 and 116 corresponds to the left-right direction.

  The partition wall 117 is disposed on the side wall 116 side inside the case 110 and is parallel to the side wall 116 to be a wall connecting the side walls 113 and 114. The partition wall 117 extends from the upper surface of the bottom wall 112 (the surface to be the inside of the case 110) to an intermediate position in the vertical direction of the case 110. A space 117 a is formed between the dividing wall 117 and the side wall 116. A battery management unit 190 described later is accommodated in the space 117a.

  The beam 118 is a reinforcing member for improving the strength of the case 110 as shown in FIGS. 1 to 3 and is parallel to the upper surface of the bottom wall 112 (the surface on the inside of the case 110). As shown, a plurality of bottles are provided. In the present embodiment, five beams 118 are set. The beams 118 are formed in a slender rod shape, and are provided on the bottom wall 112 so that the longitudinal direction is in the front-rear direction with respect to the case 110 and that the longitudinal direction is equally spaced in the left-right direction. The pitch (distance between center lines) of the beams 118 is set to be equal to the dimension of the battery cell 121 in the left-right direction.

  The beam 118 is separately formed with respect to the case 110, and is, for example, a hollow prismatic member having a square cross section. More specifically, the cross-sectional shape of the beam 118 is U-shaped, and the U-shaped opening side is fixed to the bottom wall 112. The beam 118 is made of, for example, an aluminum material or an iron material.

  A plate-like closed wall 119a connected from the side wall 113 to the side wall 114 is provided on the top surface of the plurality of beams 118 between the dividing wall 117 and the plurality of battery cells 121 (group of batteries 120). The upper side of the space between the beams 118 is closed by the closed wall 119a.

  Similarly, a plate-like closed wall 119 b connected to the side wall 113 from the side wall 113 is provided on the top surface of the plurality of beams 118 between the side wall 115 and the plurality of battery cells 121 (assembled battery 120). The upper side of the space between the beams 118 is closed by the closed wall 119b.

  The assembled battery 120 is formed by providing a plurality of cell stacks 120A in which a plurality of battery cells 121 are stacked. In the present embodiment, for example, one battery stack 120A is formed by twenty battery cells 121, and the four battery stacks 120A are arrayed to form a battery pack 120 (FIG. 1).

  The battery cell 121 is in the form of a flat rectangular parallelepiped in the front-rear direction, and includes a positive electrode terminal and a negative electrode terminal protruding outward from the outer case. The battery cell 121 corresponds to the battery of the present invention.

  A plurality of battery cells 121 are stacked in the cell stack 120A, and the stacked battery cells 121 are formed in a battery case. That is, the plurality of battery cells 121 are stacked such that the surfaces orthogonal to the flat direction face each other. The battery case has a case in which the upper surface side and the lower surface side of each battery cell 121 are opened and the periphery of each battery cell 121 is covered.

  In the cell stack 120A, terminals of different polarities in adjacent battery cells 121 are electrically connected (series connection) by conductive members such as bus bars. The connection between the bus bar and the electrode terminal is performed by, for example, screwing or welding. Therefore, the total terminal portions disposed at both ends of the plurality of battery cells 121 electrically connected by the bus bar or the like are supplied with electric power from the outside or discharged toward other electric devices. There is.

  In addition, in the cell stack 120A, a predetermined gap is formed between the plurality of battery cells 121 to be stacked. The gap is formed by a spacer member or the like provided between the battery cells 121. The spacer member can be formed, for example, by providing a partition wall between the battery cells 121 in the battery case and providing unevenness or the like on the partition wall.

  The plurality of cell stacks 120A (the battery cells 121) are fixed (arranged) on the top surface of the beam 118, as shown in FIGS. Specifically, in one cell stack 120A (each battery cell 121), both ends on the lower side in the direction (left and right direction) in which the plurality of beams 118 are arranged are placed on two beams 118 respectively. Being placed (fixed).

  The circulation passage 130 is formed in the case 110 and is in contact with the inner wall surfaces of the battery cells 121 and the case 110 (here mainly the side walls 113 and 114, the top wall 111 and the bottom wall 112) for heat exchange. Is a passage through which fluid flows. The circulation passage 130 is mainly formed of a side wall side passage 131, a side wall side passage 132, a top wall side passage 133, a battery passage 134, a bottom wall side passage 135, and a series of flow passages connecting the blowers 140A and 140B. There is.

  The side wall side passage 131 is orthogonal to both the top wall 111 and the bottom wall 112, extends parallel to the side wall 113, and is a path formed between the plurality of battery cells 121 (the assembled battery 120) and the side wall 113. It is.

  The side wall side passage 132 is perpendicular to both the top wall 111 and the bottom wall 112, extends parallel to the side wall 114, and is a path formed between the plurality of battery cells 121 (the battery pack 120) and the side wall 114. It is.

  The top wall side passage 133 is a path that is formed between the top wall 111 and the plurality of battery cells 121 (the battery pack 120) and extends parallel to the top wall 111.

  The side wall side passage 131 and the top wall side passage 133 are connected at the boundary between the top wall 111 and the side wall 113. Further, the side wall side passage 132 and the top wall side passage 133 are connected at the boundary between the top wall 111 and the side wall 114.

  The battery passage 134 is a passage formed by the gap between the adjacent battery cells 121 in each cell stack 120A.

  The bottom wall side passage 135 is a passage formed as a space surrounded by the bottom wall 112, the lower end surfaces 121 a of the plurality of battery cells 121, and the beams 118. In addition, the bottom wall side passage 135 includes the space surrounded by the bottom wall 112, the closed wall 119a and the beam 118, and further the space surrounded by the bottom wall 112, the closed wall 119b and the beam 118. ing. The bottom wall side passage 135 is a passage formed between the adjacent beams 118 on the lower side of each battery cell 121, and in the present embodiment, four passages based on the five beams 118 It is formed as.

  Of the four bottom wall side passages 135, the second passage from the side of the side wall 113 is in communication with the first passage in the vicinity of the blower 140A by a communication portion (not shown). Further, the third passage from the side wall 113 side is in communication with the fourth passage in the vicinity of the blower 140B by a communication portion (not shown).

  The upper side of the battery passage 134 is connected to the top wall side passage 133, and the lower side of the battery passage 134 is connected to the bottom wall side passage 135.

  The blower 140 is a fluid driving means which is accommodated in the case 110 and forces the fluid for heat exchange to circulate (circulate) in the circulation passage 130. In the present embodiment, the blower 140 is set so that two of the first blower 140A and the second blower 140B are aligned. Hereinafter, the two fans 140A and 140B may be collectively referred to as the fan 140. As a fluid to be circulated in the circulation passage 130, for example, air, various gases, water, a refrigerant, or the like can be used.

  As shown in FIG. 1, FIG. 2, and FIG. 4, the first fan 140A is a fan that circulates the fluid in the circulation passage 130 corresponding to the area of the two cell stacks 120A on the side wall 113 side. Further, the second fan 140B is a fan that circulates the fluid in the circulation passage 130 corresponding to the area of the two cell stacks 120A on the side wall 114 side. In the case 110, the side walls 115 and the cell stack 120A (a plurality of battery cells 121) are arranged so that the first fan 140A and the second fan 140B are symmetrical with respect to a center line facing the front-back direction of the case 110. Is placed between.

  Each blower 140 A, 140 B includes a motor 141, a sirocco fan 142, and a fan casing 143.

  The motor 141 is an electrical device that rotationally drives the sirocco fan 142, and is provided above the sirocco fan 142.

  The sirocco fan 142 is a centrifugal fan that sucks in fluid in the rotational axis direction and blows out the fluid in the centrifugal direction. The sirocco fan 142 is disposed such that the rotational axis is directed in the vertical direction.

  The fan casing 143 is formed so as to cover the sirocco fan 142, and serves as a wind guide member that sets the suction direction of the fluid by the sirocco fan 142 and the blowout direction. The fan casing 143 has a suction port 143a opened at the lower side of the sirocco fan 142, a blowout duct 143b for guiding the flow of the blown fluid, and a blowoff port 143c opened at the tip of the blowout duct 143b.

  Each suction port 143a of each blower 140A, 140B is arranged to be connected to the region on the side wall 115 side of the bottom wall side passage 135. The suction port 143a of the blower 140A is connected to the first and second passages from the side wall 113 side among the four bottom wall side passages 135. Further, the suction port 143a of the blower 140B is connected to the third and fourth passages from the side wall 113 side among the four bottom wall side passages 135.

  The blowout ducts 143b of the blowers 140A and 140B are formed to extend once from the side of the sirocco fan 142 toward the center of the case 110 and to make a U-turn so as to extend to the side wall side passages 131 and 132 respectively. ing.

  The outlet 143c of the blower 140A is disposed so as to be connected to the side wall side passage 131. Specifically, the outlet 143c is located in the vicinity of the battery cell 121 on the side of the side wall 115 among the plurality of battery cells 121 stacked on the lower side in the vertical direction in the side wall side passage 131, and It is arranged to face the side wall 116 side.

  Further, the outlet 143 c of the blower 140 B is disposed so as to be connected to the side wall side passage 132. Specifically, the outlet 143c is located in the vicinity of the battery cell 121 on the side of the side wall 115 among the plurality of battery cells 121 stacked at a position near the lower side in the vertical direction in the side wall side passage 132, and It is arranged to face the side wall 116 side.

  The PTC heater 144 is a heating device for heating the fluid in the case 110 to a predetermined temperature as shown in FIGS. 1 and 4, and is provided at an intermediate position in the fan casing 143. The PTC heater 144 has a self temperature control function, and its operation is controlled by a battery management unit 190 described later.

  As shown in FIG. 5, the internal fin 150 is a fin for promoting heat exchange provided inside the case 110, and has a first internal fin 151 and a second internal fin 152. Each internal fin 151, 152 is formed of an aluminum material, an iron material or the like which is excellent in thermal conductivity.

  The first internal fins 151 are provided on the side wall 113 side and the side wall 114 side so as to be symmetrical with respect to a center line facing the front-rear direction of the case 110. Further, the second internal fins 152 are provided at two positions on the side wall 113 side and the side wall 114 side of the top wall 111 so as to be symmetrical with respect to a center line facing the front-rear direction of the case 110.

  Here, as each internal fin 151, 152, the straight fin which can set comparatively small the flow resistance with respect to the fluid is employ | adopted, for example. In the straight fins, many thin plate-like fin portions protruding vertically from the thin plate-like substrate portion are arranged in parallel to form a fin in which a passage for fluid is formed between the fin portions.

  Each of the internal fins 151 and 152 is not limited to the above-described straight fins, but may be other corrugated fins (with or without louvers), offset fins, or the like.

  The fin portion of the first internal fin 151 vertically protrudes from the substrate portion toward the plurality of battery cells 121, and the protruding tip portion has a plurality of batteries so that more fluid can flow in the fin portion. It extends to a position close to the side of the cell 121. Further, the plate surface of the fin portion is set to be inclined toward the side wall 116 from the lower side to the upper side in the vertical direction. Further, the length of the fluid passage by the fin portion is longer as it goes from the side wall 115 side to the side wall 116 side.

  The fin portion of the second internal fin 152 vertically protrudes from the substrate portion toward the plurality of battery cells 121, and the protruding tip portion has a plurality of tips so that more fluid can flow in the fin portion. It extends to a position close to the top surface of the battery cell 121. Further, the plate surface of the fin portion is set to be inclined toward the side wall 116 toward the center side of the case 110 with respect to the lateral direction. The length of the fluid passage by the fin portion is shorter as it goes from the side wall 115 side to the side wall 116 side. The fluid passage by the fin portion of the second internal fin 152 is connected to be continuous with the fluid passage by the fin portion of the first internal fin 151.

  As shown in FIG. 6, the external fin 160 is a fin for promoting heat exchange provided on the outside of the case 110, and has a first external fin 161 and a second external fin 162. Each external fin 161, 162 is formed of an aluminum material, an iron material, or the like, which is excellent in thermal conductivity.

  The first external fins 161 are provided on the side wall 113 side and the side wall 114 side so as to be symmetrical with respect to a center line facing the front-rear direction of the case 110. Further, the second external fins 162 are provided at two positions on the side wall 113 side and the side wall 114 side of the top wall 111 so as to be symmetrical with respect to a center line facing the front-rear direction of the case 110.

  Here, as each external fin 161, 162, for example, a corrugated fin capable of setting the heat transfer performance to the fluid relatively large is adopted. Corrugated fins are generally corrugated in shape, and a large number of louvers are formed on the wave-like opposing surfaces, and a passage for fluid is formed between the wave-like opposing surfaces and between the louvers. Has become a fin.

  The external fins 161 and 162 may be straight fins such as the internal fins 151 and 152, corrugated fins without louvers, or offset fins.

  A plurality of (in this case, two) first external fins 161 are provided in a set, and in the side walls 113 and 114, the direction in which waves continue in the region corresponding to the first internal fins 151 is It is disposed so as to face the front-rear direction, and to be slightly offset to the side wall 116 side.

  A plurality of (two in this case) second external fins 162 are provided in a set, and in the region corresponding to the second internal fins 152 on the side walls 113 and 114 side of the top wall 111, waves are provided. It is arranged so that the side wall 115 side may be more or less than the first external fin 161 so that the continuous direction of the direction points in the front-rear direction.

  The outer duct 170 is a duct for circulating the cooling fluid along the outer surface of the case 110 as shown in FIG. 7 (FIG. 14). As the fluid for cooling, for example, air-conditioned air (air-cooled cooling air) in a vehicle compartment is used.

  The outer duct 170 has a flat cross-sectional shape and is provided on the outer surface of the case 110, specifically, the side walls 113 and 114, the area on the side walls 113 and 114 of the top wall 111, and the side wall 115 , And is formed so as to include (cover) the external fins 161 and 162. The inside of the outer duct 170 is mainly a flow path connecting the side walls 113 and 114, the side walls 113 and 114 side area of the top wall 111, and the side wall 115 in this order.

  Both end portions (side walls 113 and 114 side) of the outer duct 170 on the side wall 116 side are suction portions for sucking in the conditioned air. Then, on the downstream side immediately after the suction portion, there is provided a wind direction device 171 for diverting the sucked conditioned air to the lower side of the first external fin 161 and the center side of the case 110 of the second external fin 162. .

  Further, a blower 172 is provided at the center of the side wall 115 of the outer duct 170, and the upper part and the lower part of the blower 172 form a blowout part for blowing out the conditioned air. For the blower 172, for example, a turbo fan is used.

  The voltage sensor 181 is a sensor that detects the voltage in the battery cell 121 as shown in FIG. 8. For example, in the plurality of battery cells 121, all the battery cells 121 or a predetermined (at least one) battery cell 121 Provided in The voltage signal detected by the voltage sensor 181 is output to a battery management unit 190 described later.

  As shown in FIG. 8, the current sensor 182 is a sensor that detects the current in the battery cell 121 (group battery 120), and for example, a predetermined number (one or more) of conductive members of each battery cell 121 connected in series. Provided at the site of). The current signal detected by the current sensor 182 is output to a battery management unit 190 described later.

  The temperature sensor 183 (FIG. 1) is a sensor (detector) that detects the temperature in the battery cell 121. For example, in the plurality of battery cells 121, all the battery cells 121 or a predetermined (at least one) battery cell Provided in A temperature signal detected by the temperature sensor 183 is output to a battery management unit 190 described later.

  A battery management unit 190 is configured to be communicable with various electronic control devices mounted on a vehicle. The battery management unit 190 is a device that manages at least the storage amount of the battery cell 121, and is an example of a battery control unit that performs control related to the battery cell 121. Further, the battery management unit 190 monitors voltage, current, temperature, and the like related to the battery cell 121, and manages an abnormal state, a leak and the like of the battery cell 121.

  The battery management unit 190 also includes an input circuit, a microcomputer, an output circuit, and the like, as in the case of the vehicle ECU. Battery information is stored as data in the storage means of the microcomputer. The data of the stored battery information is, for example, the battery voltage, the charging current, the discharging current, and the battery temperature in the battery pack 100.

  The battery management unit 190 also functions as a control device that controls the operation of the blowers 140A and 140B, the PTC heater 144, and the blower 172. The battery management unit 190 uses the blowers 140A and 140B based on the voltage detected by the voltage sensor 181, the current detected by the current sensor 182, and the calorific value of the battery cell 121 calculated from the charging rate (open circuit voltage). And the PTC heater 144 and the blower 172 are controlled. Details of control contents of the battery management unit 190 will be described later.

  As shown in FIG. 8, the battery management unit 190 includes a charging rate calculation unit 191, an open circuit voltage calculation unit 192, a heat generation amount calculation unit 193, a rotation number calculation unit 194, a rotation number determination unit 196, and the like.

  The charging rate calculation unit 191 is a part that calculates the charging rate (State Of Charge = SOC) of the battery cell 121 based on, for example, the voltage and current of the battery cell 121.

  The open circuit voltage calculation unit 192 is, for example, a part that calculates an open circuit voltage (Open Circuit Voltage = OCV) based on the charging rate of the battery cell 121. The open circuit voltage indicates a voltage between both terminals in a state in which the battery cell 121 (assembled battery 120) is not loaded.

  The heat generation amount calculation unit 193 is a portion that calculates the heat generation amount of the battery cell 121 based on, for example, the difference (ΔV) between the open circuit voltage of the battery cell 121 and the loaded cell voltage (ΔV). The calorific value calculation unit 193 corresponds to the calculation unit of the present invention. Hereinafter, the calorific value of the battery cell 121 will be referred to as a cell calorific value.

  The rotation number calculation unit 194 is a part that calculates the rotation number for each blower 140A, 140B based on the cell calorific value.

  The rotation speed determination unit 196 is a part that outputs a rotation command to each blower 140A, 140B at the calculated rotation speed.

  The operation of the battery pack 100 configured as described above will be described with reference to FIGS. 9 to 15.

  The battery cell 121 generates heat at the time of output from which current is taken out and at the time of input to be charged. In addition, the battery cell 121 is affected by the temperature outside the case 110 according to the season, the air conditioning condition of the vehicle interior, and the like. The battery management unit 190 constantly monitors the cell heat generation amount based on the voltage and current obtained by each of the sensors 181 and 182 and the charge rate (open circuit voltage) calculated, and based on the cell heat generation amount, each blower 140A. , 140 B, and also controls the operation of the PTC heater 144 and the blower 172.

  First, in the battery management unit 190, in the charging rate calculation unit 191, for example, a voltage signal of the battery cell 121 (hereinafter, cell voltage) obtained from the voltage sensor 181 and a current signal of the battery cell 121 obtained from the current sensor 182 ( Hereinafter, using the cell current, the charging rate (SOC) of the battery cell 121 is calculated from a predetermined map, a calculation formula, and the like.

  Next, the battery management unit 190 calculates an open circuit voltage (OCV) corresponding to the charging rate in the open circuit voltage calculation unit 192, for example, from a predetermined map.

Next, battery management unit 190 uses heat generation amount calculation unit 193 using the cell voltage obtained from voltage sensor 181, the cell current obtained from current sensor 182, and the open circuit voltage calculated by open circuit voltage calculation unit 192. , Cell calorific value is calculated. Here, the cell calorific value is calculated by Equation 1 below.

  (Open circuit voltage-cell voltage) in Equation 1 is ΔV shown in FIG. 9 and is a voltage drop (voltage rise) when a load is applied to the open circuit voltage in the battery cell 121 (during discharge and charge) is there. The voltage drop (voltage rise) corresponds to the product of the cell current and the internal resistance. In addition, as data of the cell calorific value, when a plurality of cell calorific value data can be obtained, the maximum value is used.

  Next, in the battery management unit 190, as shown in FIG. 10, the cell heat generation amount calculated by the heat generation amount calculation unit 193 from the rotation number calculation map (first map) determined in advance by the rotation number calculation unit 194. The number of rotations of the blower 140 corresponding to is calculated. The first map is, for example, a map in which the number of rotations increases linearly with respect to the cell calorific value in the cell calorific value range in which the battery cell 121 needs to be cooled.

  Next, battery management unit 190 causes rotation number determination unit 196 to output a command for operating at the rotation number calculated by rotation number calculation unit 194 to blowers 140A and 140B.

  As described above, when the blowers 140A and 140B are activated, the fluid inside the case 110 circulates in the circulation passage 130 as shown in FIGS.

  That is, the fluid sucked from the suction port 143a of each blower 140A, 140B and blown out from the blowout port 143c via the blowout duct 143b flows into the side wall side passage 131 and the side wall side passage 132, respectively.

  Then, the fluid that has flowed into the side wall side passages 131 and 132 is directed from the lower side (bottom wall 112 side) to the upper side (top wall 111 side) along the inclined fins of the first internal fin 151. It flows smoothly. In each side wall side passage 131, 132, the heat of the fluid with the flow velocity is transferred to the first inner fin 151 and further released to the outside through the side wall 113, 114.

  Next, the fluid smoothly flows to the fin portion of the second inner fin 152 connected to the first inner fin 151 continuously, and flows into the top wall side passage 133 along the fin portion. The fluid that has flowed into the ceiling wall side passage 133 spreads in the ceiling wall side passage 133.

  As shown in FIG. 11, the fluid that has flowed into the top wall side passage 133 from the side wall side passage 131 mainly spreads in the region of the two cell stacks 120A on the side wall 113 side. In addition, the fluid that has flowed into the top wall side passage 133 from the side wall side passage 132 mainly spreads in the region of the two cell stacks 120A on the side wall 114 side. Then, the heat of the fluid flowing into the ceiling wall side passage 133 is transmitted from the second internal fins 152 to the ceiling wall 111 or directly transmitted to the ceiling wall 111 and released to the outside.

  Next, the fluid that has flowed into the top wall side passage 133 passes through the battery passage 134 formed between the battery cells 121 and reaches the bottom wall side passage 135. Here, the side wall side passages 131, 132 and the top wall side passage 133 become positive pressure spaces by the blowing out of the fans 140A, 140B, and the bottom wall side passage 135 is by suction of the fans 140A, 140B. This is a negative pressure space, and due to the pressure difference between the two, the movement of fluid from the top wall side passage 133 to the bottom wall side passage 135 is continuously performed. Then, when the fluid passes through the battery passage 134, the heat of each battery cell 121 is transferred to the fluid.

  Next, the fluid that has flowed into the bottom wall side passage 135 moves along the longitudinal direction of each beam 118 and reaches the suction port 143a of each blower 140A, 140B. Then, the heat of the fluid flowing into the bottom wall side passage 135 is transmitted to the bottom wall 112 and released to the outside.

  As described above, the fluid is circulated through the circulation passage 130 in the case 110, and mainly the heat of the fluid from the top wall 111, the side walls 113 and 114, and the bottom wall 112, that is, the heat of the battery cell 121 is externally output. Released. At this time, heat exchange is promoted by the internal fins 151 and 152. Thus, each battery cell 121 is effectively cooled and adjusted to an appropriate temperature.

  Here, for example, when the battery cell 121 is in a low temperature environment and the cell calorific value calculated by the calorific value calculator 193 falls below a predetermined calorific value (first calorific value) determined in advance, the battery management unit 190 operates the PTC heater 144 in addition to each blower 140A, 140B. In this case, when multiple cell heating value data can be obtained as cell heating value data, the minimum value is used.

  In addition to the fans 140A and 140B, when the PTC heater 144 is activated, the fluid flowing in the blowout duct 143b is heated by the PTC heater 144. Then, as the heated fluid circulates through the circulation passage 130 in the case 110 as described above, conversely, each battery cell 121 is heated to a temperature at which it can be properly operated by the heated fluid, and the temperature is low. The performance degradation at the time of calorific value (under low temperature) is corrected.

  Also, for example, when the battery cell 121 is in a high temperature environment, and the cell calorific value calculated by the calorific value calculation unit 193 exceeds a predetermined calorific value (second calorific value) determined in advance, the battery management unit 190 , In addition to each blower 140A, 140B, operates the blower 172. The second calorific value is a threshold value set to be larger than the first calorific value. In this case, the maximum value is used when a plurality of cell heating value data can be obtained as the cell heating value data.

  By operating the blower 172, conditioned air in the vehicle compartment is drawn into the outer duct 170 from the suction portion of the outer duct 170. As shown in FIG. 14, the conditioned air taken from the suction part is diverted by the wind direction device 171 and diverted to the lower side of the first external fin 161 and the central side of the case 110 of the second external fin 162. Ru. And each flow passes so that each external fin 161,162 may cross, merges, and blows off from the blowing part provided in the upper and lower part of the air blower 172. As shown in FIG.

  At this time, the heat of the fluid in the case 110 is transmitted to the conditioned air through the inner fins 151 and 152, the side walls 113 and 114, the top wall 111, and the outer fins 161 and 162, and is released to the outside. Therefore, the heat of the fluid in the case 110 is further promoted to the heat exchange by the respective external fins 161 and 162 in addition to the respective internal fins 151 and 152. Then, each battery cell 121 is forcibly cooled so as to have an appropriate calorific value (temperature) in a short time.

  As described above, in the present embodiment, the number of rotations of the blower 140 (140A, 140B) is controlled based on the cell calorific value. Since temperature management using the cell calorific value is feedforward control based on a factor system related to temperature change of the battery cell 121, prospective control in anticipation of the foresight becomes easy. Therefore, as shown in FIG. 15, it is possible to suppress the temperature overshoot or the like in the feedback control using the temperature as a result system, and to improve the responsiveness regarding temperature management.

  Further, since the calorific value calculation unit 193 calculates the calorific value of the cell using the open circuit voltage based on the voltage, the current, and the charge rate of the battery cell 121, the calorific value of the cell can be easily and surely. It can be calculated.

Second Embodiment
A second embodiment is shown in FIG. 16 and FIG. In the second embodiment, the battery management unit 190 of the battery pack 100 is changed to a battery management unit 190A with respect to the first embodiment. In addition to the cell calorific value, battery management unit 190A takes into account the temperature of battery cell 121 (hereinafter, cell temperature) obtained from temperature sensor 183, that is, blower 140 (according to the cell calorific value and the cell temperature). The number of revolutions of 140A, 140B) is determined (controlled).

  The temperature sensor 183 is a detector that detects a cell temperature in a predetermined battery cell 121 among the plurality of battery cells 121 as described in the first embodiment. The predetermined battery cell 121 can be at least one place as a portion where a representative temperature can be obtained among the plurality of battery cells 121. Here, in order to increase the reliability of temperature detection, the temperature sensors 183 are provided, for example, on both end sides and center sides in the stacking direction in each cell stack 120A.

  Then, as shown in FIG. 16, the battery management unit 190A determines the charging rate calculation unit 191, the open circuit voltage calculation unit 192, the heat generation amount calculation unit 193, the rotation number calculation unit 194, and the rotation number determination described in the first embodiment. In addition to the unit 196, a rotation speed calculation unit 195 is provided. Therefore, battery management unit 190A has two parts (rotational speed calculation units 194 and 195) for calculating the rotational speed of blower 140.

  The rotation number calculation unit 195 is configured to calculate the rotation number of the blower 140 from the rotation number calculation map (second map) shown in FIG. 17 based on the cell temperature obtained from the temperature sensor 183. The second map pre-associates the cell temperature with the number of revolutions to be set. In the second map, in the region where the cell temperature is relatively low, the rotation number is set to be constant, and further, as the cell temperature becomes higher, the rotation number increases linearly.

  In the present embodiment, the number of rotations calculated by the number-of-rotations calculation unit 194 (hereinafter, first rotation number) and the number of rotations calculated by the number-of-rotations calculation unit 195 (hereinafter, second rotation number) It is output to the determination unit 196.

  Battery management unit 190A instructs rotation speed determination unit 196 to operate fan 140 at a first rotation speed based on the cell calorific value, as the first operating condition for fan 140 to be turned on from the off state. Then, after that, the blower 140 is operated and controlled under the condition of the larger one of the first rotation number based on the cell calorific value and the second rotation number based on the cell temperature.

  As a result, since the operation of the blower 140 is controlled based on the cell calorific value as the first operation condition, as described in the first embodiment, temperature management that can suppress overshoot. Improvement in response to

  Further, while the operation of the battery pack 100 is continued, the rotational speed of the blower 140 is determined by looking at the conditions of both the cell calorific value and the cell temperature, so that more reliable temperature management is possible. Become.

(Modification of the second embodiment)
The modification of the said 2nd Embodiment is shown in FIG. 18, FIG. A modification of the second embodiment is that the battery management unit 190A is changed to a battery management unit 190B in the second embodiment. In battery management unit 190B, rotational speed calculation units 194 and 195 in battery management unit 190A are eliminated, and rotational speed determination unit 196 is provided with a rotational speed calculation map (third map) shown in FIG. There is.

  The third map is a map in which the number of rotations of the blower 140 is predetermined when the cell calorific value obtained from the calorific value calculation unit 193 and the cell temperature obtained from the temperature sensor 183 are variables. In the third map, the number of rotations is set to be larger as the cell calorific value is larger, and the number of rotations is set to be larger as the cell temperature is higher. Furthermore, in the third map, even under the condition that the cell temperature is low, the rotational speed is set to be at an intermediate level from the stage where the cell calorific value is low. That is, as the first operating condition of the blower 140, the rotational speed setting based on the cell calorific value is prioritized.

  In the third map of FIG. 19, the respective rotation speed levels are described as “OFF”, “medium”, and “high” for the sake of simplicity of the description, but, for example, at a predetermined rotation speed pitch, The number of revolutions may be set in multiple stages.

  As described above, battery management unit 190 B determines the number of rotations of blower 140 based on the third map in rotation number determination unit 196, and controls the operation of blower 140. Thereby, the same effect as that of the second embodiment can be obtained.

Third Embodiment
A third embodiment is shown in FIGS. In the third embodiment, the battery management unit 190A of the battery pack 100 is changed to a battery management unit 190C with respect to the second embodiment. The battery management unit 190C calculates the basic rotation number of the blower 140 based on the cell temperature, corrects the basic rotation number according to the internal resistance of the battery cell 121, and determines the command value for the blower 140. There is.

  As illustrated in FIG. 20, the battery management unit 190C includes a rotation speed calculation unit 195, an internal resistance estimation unit 197, a correction coefficient calculation unit 198, a rotation speed determination unit 199, and the like.

  The rotation number calculation unit 195 is the same as that described in the second embodiment, and is a part that calculates the rotation number of the blower 140 based on the cell temperature obtained from the temperature sensor 183 (see FIG. 17). map). Here, the rotation speed calculated by the rotation speed calculation unit 195 is the basic rotation speed that is the basis of control.

  The internal resistance estimating unit 197 estimates the internal resistance (hereinafter, internal cell resistance) of the battery cell 121 using, for example, the cell voltage obtained from the voltage sensor 181 and the cell current obtained from the current sensor 182. is there. The internal resistance estimation unit 197 corresponds to the estimation unit of the present invention. The internal cell resistance corresponds to the inclination on the coordinate in the relation between the cell voltage and the cell current as shown in FIG. As the cell internal resistance is larger, the cell calorific value at the time of operation is larger.

  The correction coefficient calculation unit 198 is a unit that calculates a correction coefficient for correcting the basic rotation number according to the cell internal resistance estimated (obtained) by the internal resistance estimation unit 197. The correction coefficient is calculated from, for example, a correction coefficient map shown in FIG. The correction coefficient map is set so that the correction coefficient is 1 in a region where the cell internal resistance is relatively small, and the correction coefficient becomes larger than 1 as the cell internal resistance increases.

  The rotation number determination unit 199 corrects the basic rotation number calculated by the rotation number calculation unit 195 with the correction coefficient calculated by the correction coefficient calculation unit 198 to determine the correction rotation number, and the blower 140 is used. It is a part that outputs a rotation command.

  As shown in FIG. 22, battery management unit 190 C uses correction coefficient calculated by correction coefficient calculation unit 198 with respect to the basic rotation number calculated by rotation number calculation unit 195 in rotation number determination unit 199 as shown in FIG. The multiplication is performed to determine the correction rotational speed, and the corrected rotational speed is output to the blower 140.

  In the present embodiment, after the basic rotation number is calculated based on the cell temperature, the basic rotation number is corrected according to the cell internal resistance (the correction rotation number is calculated), and is determined as the command value. The cell internal resistance is a physical quantity related to the cell calorific value. Therefore, by adding the condition of the cell internal resistance to the cell temperature, the meaning of control based on the cell calorific value is added, and prospect control with respect to the cell temperature becomes easy, and the response regarding the temperature management of the battery cell 121 It is possible to improve

(Other embodiments)
Although the preferred embodiments of the present invention have been described in the above embodiments, the present invention is not limited to the above embodiments and can be variously modified and implemented without departing from the spirit of the present invention. It is. The structures of the aforementioned embodiments are merely illustrative, and the scope of the present invention is not limited to the scope of these descriptions. The scope of the present invention is defined by the description of the claims, and further includes all modifications within the meaning and scope equivalent to the descriptions of the claims.

In the above embodiments, the cell heat generation amount is calculated from the cell voltage, cell current, and charging rate (open circuit voltage). However, the present invention is not limited to this, and may be calculated from cell current and cell internal resistance. Good. The cell internal resistance is estimated from the cell voltage and the cell current as described in the third embodiment. The cell calorific value is calculated by (cell current) ² × cell internal resistance.

  Also, the first map described in FIG. 10, the second map described in FIG. 17, and the correction coefficient map described in FIG. 21 increase linearly according to the cell heat generation amount, the cell temperature, and the cell internal resistance, respectively. Although it is assumed, it may be increased stepwise.

  The essential components of the present invention are the case 110, the battery pack 120, the circulation passage 130, the blower 140, the voltage sensor 181, the current sensor 182, the temperature sensor 183 (second to third embodiments), and the battery management unit (control Sections 190 and 190A to 190C, and the PTC heater 144, the inner fins 150, the outer fins 160, and the outer duct 170 may be set as needed.

  Further, the fluid in the case 110 of each of the embodiments described above passes through the circulation passage 130, the blower 140 (140A, 140B), the side wall side passages 131, 132, the top wall side passage 133, the battery passage 134, and the bottom wall side passage. Although the circulation is made in the order of 135, it may be reversed.

  Moreover, although the battery pack 100 of each said embodiment was made to circulate a fluid through the circulation passage 130 using two air blowers 140A, 140B, the circulation passage 130 is carried out by one air blower or three or more air blowers. Fluid may be circulated.

  In addition to the sirocco fan described in each of the above-described embodiments, an axial fan, a turbofan, or the like can be used as the fan incorporated in the blower 140 (140A, 140B) provided inside the case 110.

  Further, in setting the inner fins 150 and the outer fins 160, the fins may be integrally formed on the side walls 113 and 114 and the top wall 111.

  When the PTC heater 144 as a heating device is provided, the PTC heater 144 may be replaced by an electric heater, a heat pump (heating heat exchanger), a combustion heater, or the like. Further, the PTC heater 144 may be provided outside the fan casing 143 not only inside the fan casing 143 but inside the case 110.

  In the above embodiment, the case 110 forms a hexahedron or a rectangular parallelepiped, but the case included in the invention is not limited to this shape. For example, the case 110 may be a polyhedron having six or more faces, or at least one face may be a face including a curved surface. In the case 110, the top wall 111 may be formed in a dome shape including a curved surface, or the vertical cross-sectional shape of the case 110 may have a trapezoidal shape. Further, in the case 110, the top wall 111 is a wall in a positional relationship facing the bottom wall 112, and the shape thereof may include any shape of a flat surface and a curved surface. In the case 110, the side walls 113 to 116 may be walls extending from the bottom wall 112 in a direction intersecting with the bottom wall 112, or walls extending from the top wall 111 in a direction intersecting with the top wall 111. It may be The boundary between the top wall 111 and the side walls 113 to 116 in the case 110 may form a corner or may form a curved surface. The boundary between the bottom wall 112 and the side walls 113 to 116 in the case 110 may form a corner or may form a curved surface.

  Further, in the above embodiment, the number of the cell stacks 120A included in the battery pack 100 is four, but the number is not limited to this. That is, when only one cell stack 120A included in the battery pack 100 is accommodated inside the case 110, and when a plurality of the cell stacks 120A are installed side by side in one direction, they are in the other direction intersecting the one direction. This also includes the case where a plurality of units are installed side by side.

100 battery pack 110 case (case)
121 battery cells
130 circulation passage 140 blower 183 temperature sensor (detector)
190, 190A to 190C Battery management unit (control unit)
193 Heat generation amount calculation unit (calculation unit)
197 Internal resistance estimation unit (estimation unit)

Claims (4)

With multiple batteries (121),
A housing (110) for housing a plurality of the batteries (121);
A circulation passage (130) formed in the housing (110) and passing through a fluid for heat exchange so as to contact the plurality of batteries (121) and the inner wall surface of the housing (110);
A blower (140) housed in the housing (110) and circulating the fluid through the circulation passage (130);
A control unit (190) for controlling the operation of the blower (140);
A calculation unit (193) for calculating a calorific value of a predetermined battery (121) among the plurality of batteries (121);
A detector (183) for detecting a predetermined temperature of the battery (121);
The control unit (190) is configured to determine the number of rotations of the blower (140) based on the calorific value obtained by the calculation unit (193).
The control unit (190) commands the fan (140) to operate at a first rotation speed based on the heat generation amount as the first operating condition for the fan (140) to be turned on from the off state, and the operation is performed After the fan, the fan (the first rotation number based on the calorific value and the second rotation number based on the temperature obtained by the detector (183), which is the larger one of the rotation 140) A battery pack characterized by controlling operation. The battery pack according to claim 1 , wherein the calculation unit (193) calculates the heat generation amount from the current, the voltage, and the charging rate of the battery (121). The battery pack according to claim 1 , wherein the calculation unit (193) calculates the heat generation amount from the current of the battery (121) and the internal resistance. The battery pack according to claim 3 , wherein the calculation unit (193) estimates the internal resistance from the current and a voltage of the battery (121).

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