Fast-charging battery unit and indoor-installable charging station capable of charging it

Abstract

The present invention aims to provide a rapid charging battery unit for use in electric motorcycles and other electric light vehicles, as well as electric robots, and an indoor charging station capable of charging it. [Solution] This rapid charging battery unit comprises a battery case in which a plurality of rechargeable sheet-shaped battery cells are arranged in parallel, and the positive and negative terminals of each cell are connected in series / parallel with conductive busbars and sealed inside; and a plate-shaped heat absorption / dissipation means made of copper, aluminum, or graphite resin, positioned in the charging region of each battery cell, having a heat absorption portion interposed in a layered parallel manner between the outer surfaces of each battery cell and / or arranged in parallel on the outer surface of the outermost battery cell, and a heat dissipation portion connected to the edge of the heat absorption portion and exposed to the outside.

Description

Technical Field

[0001] The present invention relates to a rapid charging battery unit used for electric motorcycles and other electric light vehicles and electric robots, and an indoor-installable charging station capable of charging the same.

Background Art

[0002] In recent years, electric vehicles and the like have become popular. However, one of the factors hindering their popularization is that the charging time is long, and the need for rapid charging is increasing. For example, in the case of an electric vehicle, the power source is connected to the vehicle's charging inlet at a rapid charging station, and the supplied alternating current power is converted into direct current by an AC-DC converter (rectifier) to charge the charging unit in the vehicle. Currently, in such rapid charging stations, the output is being increased in order to shorten the charging time.

[0003] On the other hand, when the output is increased in such a rapid charging stand, the charging current exceeds a predetermined value during rapid charging, and the amount of heat generated in the charging circuit and the rechargeable battery exceeds the allowable upper limit, necessitating the need to overcome safety problems. In addition, in order for a rechargeable battery such as a lithium-ion battery to exhibit its original performance, it needs to be used in a temperature environment within a predetermined range. Although it is conceivable to implement charging restrictions in order to reduce the amount of heat generated, this would limit the charging at the desired charging time and charging current value while attempting rapid charging, and there is a risk that the shortening of the charging time cannot be substantially achieved. Therefore, in order to achieve rapid charging, it is necessary to cool the charging current path and the rechargeable battery.

[0004] For example, there are technologies that provide cooling units in the vehicle's charging inlet or harness (Patent Document 1 (JP 2022-25813 A), Patent Document 2 (JP 2019-115253 A)), but these assume cases where a large-capacity rechargeable battery, such as that of an electric vehicle, allows for the installation of complex cooling structures and control configurations inside the vehicle. They are not immediately applicable to a wide variety of electric-driven vehicles, such as the electric motorcycles and light vehicles that have been developing in recent years. Furthermore, they cannot be applied when the built-in space for the charging unit and its peripheral equipment is small, or when the charging unit is removed and fast-charged separately at a charging station.

[0005] Furthermore, as a technology to achieve rapid charging on the charging device side rather than the vehicle side, there is a technology that charges a battery unit installed in a charging unit having an AC-DC converter (rectifier) ​​by supplying power to it (for example, Patent Document 3 (Japanese Patent Publication No. 2012-19602)). In such technology, the charging unit is equipped with an AC-DC converter, transformer, control device, switch, breaker, etc., and the battery unit to be cooled is, for example, a case in which multiple lithium-ion battery cells are housed horizontally and cooled by air cooling with a cooling fan equipped on the charging unit side. However, improvements that take air convection into consideration (for example, Patent Document 4 (Japanese Patent Publication No. 2014-123475)) had the problem that the battery cells could not be sufficiently cooled or the device became larger.

[0006] Furthermore, in recent years, there has been a significant potential need for cooling measures in small and medium-sized rechargeable battery units with small battery capacities used in advanced humanoid robots, agricultural robots, and factory transport vehicles, and a solution to the above-mentioned problems is desired. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2022-25813 [Patent Document 2] Japanese Patent Publication No. 2019-115253 [Patent Document 3] Japanese Patent Publication No. 2012-19602 [Patent Document 4] Japanese Patent Publication No. 2014-123475 [Overview of the project] [Problems that the invention aims to solve]

[0008] In view of the above, the present invention was created with the aim of providing a compact, high-cooling-efficiency rapid-charging battery unit for use in electric motorcycles and other electric light vehicles, electric robots, etc., and an indoor-installable charging station capable of charging it. [Means for solving the problem]

[0009] The present invention comprises a battery case in which multiple rechargeable sheet-like battery cells are arranged in parallel, and their positive and negative terminals are connected in series / parallel with conductive busbars, and which is enclosed and sealed. In the charging region of each of the aforementioned battery cells, a plate-shaped heat absorption / dissipation means made of copper, aluminum, or graphite resin is positioned, having a heat absorption portion interposed in a layered manner between the outer surfaces of each of the aforementioned battery cells and / or arranged in parallel on the outer surface of the outermost battery cell, and a heat dissipation portion connected to the edge of the heat absorption portion and exposed to the outside. We provide a rapid charging battery unit equipped with the following features.

[0010] The present invention envisions a rapid-charging battery unit that is both miniaturized and has increased electromotive force, and provides a specific configuration that can withstand rapid charging in such a battery unit. Specifically, in the battery unit of the present invention, as a method of increasing electromotive force, common flat and rectangular bag-shaped battery cells (see Figure 2) are arranged in layers in parallel within the battery case, and the positive and negative terminals of each battery cell are connected in series / parallel with copper or equivalent conductive busbars to constitute the input and output terminals of the entire battery unit. As mentioned above, when charging such a type of rechargeable battery unit, if it is connected to a high-output charging unit for rapid charging, the amount of heat generated increases, and it is necessary to cool it to prevent it from exceeding safe tolerance limits.

[0011] The inventors have diligently studied how to make the battery unit itself easier to cool, prior to any external cooling. In particular, the problem of increased heat generation during charging has been a focus of development, mainly for EV battery units, which have a large capacity, are easy to install cooling equipment in the vehicle body, and have sufficient charging space. As a result, the cooling challenges of small and medium-sized battery units for light vehicles such as electric motorcycles and humanoid robots, which are expected to see further development in the future, have not received much attention.

[0012] The inventor, in the process of developing and providing light vehicles such as electric motorcycles, considered that the necessary requirements for market introduction of battery units for these vehicles were convenience of driving, reduced charging time, ease of installation and space saving of charging stations, removal during charging, and applicability to harsh charging environments. In fact, in the case of battery units for light vehicles such as electric motorcycles, it has become clear that simply using external air cooling is insufficient to reach between each battery cell, and cooling the entire charging station requires a large charging station and a large cooling device, which does not meet the requirements of recent SDGs.

[0013] On the other hand, the inventors have investigated the temperature rise during charging, including during high summer temperatures, in battery units that simply arrange multiple battery cells in parallel, particularly those used in electric motorcycles and other light vehicles as described above. They have found that the temperature rise approaching the allowable heat generation is actually observed in the battery cells near the connection to the charging unit (at least in the charging-side portion where significant heat generation is expected (hereinafter also referred to as the "heat-generating portion")), and that the temperature rise is significantly smaller in portions further away from the charging unit. Based on this finding, the present invention provides a structure that directly absorbs heat only in the portions of each battery cell within the battery unit that are likely to generate a large amount of heat, conducts the absorbed heat to the outside, and dissipates it by exposing it to the outside.

[0014] Specifically, heat is absorbed by first inserting plate-shaped heat-absorbing sections in parallel with the battery bag, in contact with or near the heat-generating points between each battery cell (or the outer surface of the outermost battery cell). High thermal conductivity materials such as copper, aluminum, or graphite resin are used. This allows for concentrated heat absorption at the heat-generating points of each battery cell, even in a confined space, while simultaneously conducting heat throughout the entire heat-absorbing section. Furthermore, by connecting each heat-absorbing section with an externally exposed component of the same high thermal conductivity material, a concentrated cooling area is created to release the absorbed and conducted heat to the outside.

[0015] Furthermore, it is preferable that each of the aforementioned battery cells is a rechargeable battery capable of rapid charging at 1.0C or higher, and that they are connected in series or parallel within the battery case.

[0016] This suitable rapid-charging battery unit is intended for rechargeable batteries capable of rapid charging at 1.0C or higher. The rapid-charging batteries targeted here are those whose structure is maintained and does not break even when subjected to high ion mobility (current). Because the structure does not break even when subjected to high ion mobility (current), for example, the layer thickness can be thin, or the interaction between ions (typically Li ions) and the constituent elements can be reduced. The unit C used here refers to the charge / discharge rate, representing how many times the current value at which the battery charges and discharges is compared to its discharge capacity (Ah). For example, 1.0C, 10.0C, and 0.5C represent currents that are 1.0, 10.0, and 0.5 times the battery's discharge capacity, respectively.

[0017] Generally, a sudden surge of high current into the battery cells causes the solution temperature to rise, leading to separator degradation. Furthermore, a high load on the internal impedance can prevent sufficient current from being supplied, resulting in a voltage drop. This voltage drop and insufficient current inevitably prolong the charging time, hindering rapid charging. Therefore, when attempting rapid charging, it is necessary to reduce the impedance of the charging battery unit to prevent voltage drop.

[0018] Taking the example of lithium-ion batteries in electric vehicles, in the case of general electric vehicles, because the required output current is large, lithium-ion batteries with high energy density (nominal battery voltage (V) × rated battery capacity (Ah) / battery weight (kg)) are selected. On the other hand, in order to prevent voltage drop, a method has been adopted in which each lithium-ion cell (corresponding to the individual battery cells mentioned above) is connected in parallel to reduce impedance. This parallel connection method was possible in the case of electric vehicles because the volume in which the charging battery unit can be installed is relatively large. Specifically, NCA (nickel-cobalt-aluminum) lithium-ion batteries, NMC (nickel-manganese-cobalt) batteries, and lithium iron phosphate batteries (LiFePO4 batteries) have been used.

[0019] On the other hand, in the case of a light vehicle such as an electric motorcycle, since the volume available for mounting the charging battery unit is small, it is difficult to secure output by connecting each battery cell in parallel as in a conventional electric vehicle, and it is desirable to secure output by connecting them in series. On the other hand, series connection increases impedance and causes voltage drop, resulting in the contradictory problem that the charging time is extended as described above. Therefore, in selecting a battery for a light vehicle such as an electric motorcycle, the inventor decided to reduce the impedance of the unit by adopting a series connection while giving priority to ensuring output power and miniaturization, and by adopting a battery with low impedance of the battery itself.

[0020] In addition, in an indoor-installable charging station capable of charging the rapid charging battery unit described above, The rapid charging battery unit is detachably mounted as a drive source of an electric light vehicle, and is connected to a bus bar that connects the terminals of each battery cell so as to be chargeable via a charging inlet from an external AC power source. The charging inlet has an AC / DC converter and is provided with a control board for controlling power supply to the bus bar. The charging station is Composed of an integrated housing having a plurality of charging compartments each having a charging outlet for the rapid charging battery unit connected to an external AC power source inside. Each charging compartment can be positioned inside with the rapid charging battery unit exposed to the outside. A power supply unit capable of cooling each battery cell of the charging battery unit is installed in each charging compartment, and the power supply unit is connected to the charging outlet for the rapid charging battery unit or separately to an external power source.

[0021] The above-mentioned rapid charging battery unit is charged at a charging station that can be installed indoors. Conventionally, when the battery cells of a charging battery become hot, the charging efficiency decreases, leading to a situation where rapid charging is not possible. Therefore, generally, means for cooling the battery cells during charging are provided. For small and medium-sized charging batteries compared to EV vehicles such as electric light vehicles, it is considered a necessary requirement for market expansion to provide a small-sized charging station according to the actual situation.

[0022] Based on this, the charging station for charging the rapid charging battery unit provided can be installed in an indoor space where there are indoor occupants such as convenience stores and offices. It can utilize the indoor temperature at a level where people can stay, enabling high cooling performance. That is, it is advantageous in that it can withstand rapid charging sufficiently by also using the ambient temperature management similar to indoor air conditioning without preparing separate cooling equipment, and it is optimal as a charging station for electric light vehicles.

[0023] Specifically, in this charging station, there are a plurality of charging compartments in the housing, such as a charging compartment that is open to the indoor space side and a charging compartment that houses most of the rapid charging battery unit in a state of being exposed in the indoor space. At least in a state where there are exposed parts to the outside, the rapid charging battery unit can be positioned inside. Therefore, even in summer, the cooling of the rapid charging battery unit during charging can be supplemented by using the indoor air cooled by a cooler or the like. Furthermore, a major feature is that each charging compartment can supply power to the charging outlet of the rapid charging battery unit placed in the charging compartment and the power supply unit that can cool each rapid charging battery unit.

[0024] Furthermore, since it is a charging station that can be installed indoors, it can be charged in an environment with a reduced saturated vapor pressure, and problems such as dew condensation prevention and rainy weather environment can also be solved. As a result, it is also advantageous in that the safety of the battery is improved and the long life of the battery can be promoted.

[0025] Furthermore, it is preferable that each charging compartment of the housing is equipped with a charging management means for monitoring the supply of power from the charging outlet to the rapid charging battery unit, and that the charging management means has a locking means that closes or partially closes from an open state on the indoor space side when the charging inlet of the rapid charging battery unit is connected to the charging outlet in the charging compartment and power is supplied to the rapid charging battery unit from an external power source, and that when the power supply to the rapid charging battery unit is completed, the charging completion indicator means displays a charging completion indicator and executes control to release the locking means.

[0026] The charging station described above monitors the power supply to the rapid charging battery unit inserted into each charging compartment. Specifically, the charging inlet of the rapid charging battery unit is connected to the charging outlet in that charging compartment. When power supply begins, the open state of the charging compartment is closed or partially closed to prevent the rapid charging battery unit from being removed. Once charging is complete, the closure or partial closure is released, and the compartment becomes open again, allowing the rapid charging battery unit to be removed.

[0027] Furthermore, the rapid charging battery unit in the charging station has a battery case as a housing, which has a battery mounting space on one side (upper in the example of Figure 4) in which a plurality of the battery cells arranged in parallel and connected to each other by busbars are sealed and arranged inside, and which extends to the other side of the battery mounting space (downward in the example of Figure 4) and has a bottom portion that is open to the outside at the other end (lower end in the example of Figure 4) to guide connection to an external power supply unit. The battery mounting space and the lower part are separated by a fixing portion, Preferably, the fixed portion is fitted with a control board connected to the busbar to perform power supply control to the battery cell, and a charging inlet connected to the control board to receive a charging outlet from an external power source inside the base portion and supply power to the external power source.

[0028] As a typical example of the structure of this rapid charging battery unit in this charging station, for example, in the example shown in Figure 4 in the embodiment, a battery mounting space is provided above the battery case which serves as the housing, and below it is a base that guides the connection to the charging outlet, with a partition (fixing part) between the two inside. The partition (fixed section) is fitted with a control board that connects to the busbars of the battery cells to control the supply of power to the battery cells, and a charging inlet. The charging outlet of the power supply unit is then connected to the charging inlet housed in the lower section, and charging is performed.

[0029] In particular, the battery mounting space and the base are separated, and the base prevents the charging inlet and charging outlet 208 from being exposed to the outside. Furthermore, the base also serves as a guide member for connection to the power supply unit, which is advantageous. Although the example in Figure 4, as an embodiment, is described with the battery mounting space at the top and the base at the bottom, assuming vertical placement within a charging station, in reality, other placements such as horizontal or diagonal placement are also conceivable. [Effects of the Invention]

[0030] The present invention provides a structure that concentrates and directly absorbs heat from areas within each battery cell in the battery unit that are likely to generate a large amount of heat, conducts the absorbed heat to the outside, and dissipates it by exposing it to the outside. This makes it possible to provide a compact, fast-charging battery unit with high cooling efficiency during charging, which can be used in electric motorcycles and other electric light vehicles, electric robots, and the like.

[0031] Furthermore, according to the charging station of the present invention, sufficient rapid charging can be achieved by using ambient temperature control similar to that of indoor air conditioning, without the need to prepare separate cooling equipment. [Brief explanation of the drawing]

[0032] [Figure 1]This is a schematic diagram illustrating the rapid charging battery unit of the present invention and a power supply unit that receives it and supplies current, with (a) being a schematic perspective view of the charging battery unit and (b) being a schematic cross-sectional view of the charging battery unit in a state where it is received by the power supply unit. [Figure 2] This shows a photographic example of a battery cell used in the rapid charging battery unit of the present invention. [Figure 3] This is a schematic cross-sectional view of a specific example of a cooling structure for a power supply unit. (a) shows the first cooling structure example on the right and the second cooling structure example on the left, and (b) shows an example where the second cooling structure example on the left of (a) is placed on both sides of the charging battery unit. [Figure 4] A schematic cross-sectional view of a specific structural example of this rapid charging battery unit is shown. [Figure 5] (a) is a schematic diagram of the charging station as seen from the front, and (b) is a schematic perspective view showing each charging compartment of the charging station and an image of the charging battery unit placed inside it. [Figure 6] (a) is a roughly downward perspective view of the rapid charging battery unit showing the charging inlet installed inside the bottom of the battery case; (b) is a perspective photograph (top), side view (bottom left), and connection side plan view (bottom right) of the charging outlet of the power supply unit; and (c) is a perspective photograph (top), side view (bottom left), and connection side plan view (bottom right) of the charging inlet. [Figure 7] This is a control flow diagram for charging this rapid charging battery unit when connected to a power supply unit. [Figure 8] Figure 3 shows a detailed modification of the left schematic diagram of the cooling structure of the power supply unit, with (a) being a general perspective view and (b) being a general cross-sectional view of (a). [Figure 9] Figure 8 shows photographic examples of cooling fans actually used; (a) is a photograph of Figure 8(b) viewed from the right diagonal side, and (b) is a photograph of Figure 8(b) viewed from the left diagonal side. [Figure 10]This is a specific configuration example showing how the rapid charging battery unit is cooled by the cooling structure of the power supply unit when it is placed in each charging compartment of the charging station. (a) is a schematic perspective view showing the rapid charging battery unit in each charging compartment, and (b) is a schematic perspective view showing an example of the installation of the cooling structure of the power supply unit shown in Figure 8 when the rapid charging battery unit in the state of (a) is being charged. [Best Mode for Carrying Out the Invention]

[0033] Hereinafter, an example of one embodiment of the rapid charging battery unit of the present invention will be described with reference to Figures 1 and 4, etc. First, Figure 1 is a schematic diagram showing a rapid charging battery unit (hereinafter referred to as the "charging battery unit") 100 and a power supply unit 200 that receives it and supplies current to it. (a) is a schematic perspective view of the charging battery unit 100, and (b) is a schematic cross-sectional view along the XY plane below the Z direction of (a) in the state in which the charging battery unit 100 is received by the power supply unit 200.

[0034] As shown in Figure 1, the rechargeable battery unit 100 has multiple rechargeable battery cells 104 housed inside a hollow rectangular parallelepiped or similar shaped battery case 102 made of insulating material. Each battery cell 104 used as a rechargeable battery here is a lithium manganese oxide (LiMnO2 battery) as illustrated in the photographic diagram in Figure 2, and contains lithium manganese oxide, a separator, and an electrolyte enclosed in a rectangular bag 104c made of an insulating material such as laminate film, with a strip-shaped anode 104a and cathode 104b protruding from one edge. The component composition of a battery cell 104 suitable for use in this rechargeable battery unit 100 will be described later.

[0035] As shown in Figure 1, each of these battery cells 104 is inserted into the battery case 102 and stacked in parallel so that their respective positive and negative electrodes 104a and 104b face the same direction. The battery cells 104 are connected in series or in parallel by connecting their respective positive and negative electrodes 104a and 104b with a single conductive busbar made of copper or the like.

[0036] Furthermore, the rechargeable battery unit 100 is equipped with a heat absorption and dissipation means 110 for absorbing the heat generated in each battery cell 104 during charging and releasing it to the outside. The heat absorption and dissipation means 110 consists of a heat absorption section 106 and a heat dissipation section 108. First, the heat absorption section 106 is a plate-shaped member made of highly conductive copper (Cu), aluminum (Al), or graphite resin, which is inserted into the gaps (between stacks) of each battery cell 104 that are stacked in parallel within the battery case 102, and is in contact with the outer surface of each battery cell 104. Note that for the battery cells 104 located on both ends, there are no battery cells 104 located opposite them, so the heat absorption section 106 is not inserted into the gaps of the battery cells 104, but rather the heat absorption section 106 is stacked to cover one surface that is exposed to the outside of the battery cell 104.

[0037] Furthermore, in this rechargeable battery unit 100, as mentioned above, the temperature of the battery cells 104 generates a particularly large amount of heat during charging, and in order to cool the parts that are prone to a significant temperature rise, a heat-absorbing section 106 with a sufficient area to cover the area on the surface of each battery cell 104 near the charging terminals ("heat-generating area"), that is, the area near the charging inlet 116 (described in detail later in Figures 4 and 6). This heat-absorbing section 106 absorbs heat from the outer surface of each battery cell 104 and transfers it to the heat-dissipating section 108, which will be described later.

[0038] Furthermore, the width of the heat-absorbing section 106 is greater than the width of each battery cell 104, and as shown in Figure 1(b), both edges 106a protrude from each battery cell 104. The edges 106a of each heat-absorbing section 106 are connected by welding or other means to a heat-dissipating section 108, which is a plate-shaped member made of copper (Cu) or aluminum (Al) and whose outer surface is exposed to the outside of the battery case 102, approximately perpendicular to the edge 106. This heat-dissipating section 108 can release the heat from each battery cell 104 that has been transferred from the heat-absorbing section 106 to the outside.

[0039] Next, a specific structural example of the rechargeable battery unit 100 will be outlined. Figure 4 shows a schematic cross-sectional view of a specific structural example of the rechargeable battery unit 100. In this example of the rechargeable battery unit 100, a battery mounting space 102a is provided above the battery case 102, and the above-mentioned multiple stacked battery cells 104 (with heat absorption / dissipation means 110 interposed, though not shown) are arranged inside. The multiple battery cells 104 are connected to each other by busbars 114, and the busbars 114 and the control board 120 are connected by conductive cables 118. This control board 118 is fixed to a fixing part 102d, such as a partition, inside the battery case 102, which is located below the battery mounting space 102a, and is positioned inside the battery mounting space 102a, and controls the power supply to the battery cells 104.

[0040] The battery case 102 is also provided with a base portion 102b that extends downwards, and this base portion 102b forms an opening that opens downwards with the fixing portion 102d as the ceiling. Inside this opening, a connection space 102c is formed for connecting the charging inlet 116 for the battery cell 104 to the charging outlet 208 for the external power supply unit 200 (described later).

[0041] Therefore, the presence of the base portion 102b prevents the charging inlet 116 and charging outlet 208 from being exposed to the outside, and the base portion 102b can also serve as a guide member for connection to the power supply unit 200 (described later). In addition, this charging battery unit 100 can be charged by power from the power supply unit 200 via a conductive cable 212 connected to the charging outlet 208, but it can also be guided by the base portion 102b to a battery receiving part in a light vehicle such as an electric motorcycle and connected to an inlet (not shown) on the light vehicle side to supply power.

[0042] In the example of the specific structure of the rechargeable battery unit 100 shown in Figure 4 above, the battery mounting space 102a is described as being located at the top and bottom 102b at the bottom, assuming that the unit is placed vertically within a charging station. However, the rechargeable battery unit 100 may also be placed horizontally or diagonally within a charging station, and the terms "upper," "lower," and "bottom end" described above are merely illustrative explanations of the relative positional relationships of each component.

[0043] Next, the power supply unit 200 will be outlined again, referring to Figures 1, 3-5, 8, and 10(b) mentioned above. As shown in the schematic cross-sectional view of Figure 1(b), the power supply unit 200 has a housing (not shown) that can receive the base portion 102b of the battery case 102 of the charging battery unit 100 when it is standing upright with the battery case 102 facing downwards, as described above in Figure 4. As mentioned above, the battery case 102 of the charging battery unit 100 may also be placed horizontally or diagonally, but here we will explain it using a vertical orientation as an example.

[0044] First, the housing of the power supply unit 200 is equipped with a charging outlet 208 that connects to the charging inlet 115 inside the bottom portion 102b of the battery case 102 when the bottom portion 102b of the battery case 102 is received, as described above. Therefore, as described above, simply by receiving the battery case 102 into the housing of the power supply unit 200, current from the power supply 210 automatically becomes available to charge each battery cell 104 via the conductive cable 212, charging outlet 208, charging inlet 116, control board 120, conductive cable 118, and busbar 114. The terminals connecting the charging inlet 116 and the charging outlet 208 when the battery unit 100 is received by the power supply unit 200 and made available for charging will be described later.

[0045] Furthermore, the power supply unit 200 is equipped with a heat-absorbing member (heat-conducting contact member) 202, a Peltier element plate 204, and a cooling fan 206 on the battery case 102 side as a cooling structure for each battery cell 104 in the charging battery unit 100 during charging. Figure 1(a) shows a schematic cross-sectional view of the cooling structure of the power supply unit 200 that cools the charging battery unit 100, and Figure 3 shows schematic cross-sectional views of specific examples of the cooling structure of the power supply unit 200 in (a) and (b), respectively. In (a), the right side shows an example of the first cooling structure, and the left side shows an example of the second cooling structure, and in (b), an example of the second cooling structure on the left side of (a) being placed on both sides of the charging battery unit 100 as imagined to be placed in the charging section 304 of the charging station 300, which will be described later. Furthermore, Figure 8 shows a detailed modification of the left schematic diagram of the cooling structure of the power supply unit 200 shown in Figure 3, with (a) being a roughly oblique view and (b) being a roughly cross-sectional view. In addition, Figure 9 shows a photographic example of a cooling fan 206 actually used, as shown in Figure 8, with (a) being a photographic view from the right oblique side of Figure 8(b) and (b) being a photographic view from the left oblique side.

[0046] As described above with reference to Figure 1, the heat absorption and dissipation means 110 of the charging battery unit 100 has a heat absorption section 106 made of copper (Cu), aluminum (Al), or graphite resin inserted into the gap at the heat-generating location below each battery cell 104, and a heat dissipation section 108 made of copper (Cu) or aluminum (Al) connected to it is exposed to the outside of the battery case 102, so that the heat from each battery cell 104 is transferred from the heat absorption section 106 to the heat dissipation section 108. The cooling structure of the power supply unit 200 has a structure that absorbs and dissipates the heat transferred to the heat dissipation section 108.

[0047] Specifically, the heat-absorbing member 202 of the power supply unit 200 first comes into contact with the heat-dissipating section 108 of the rechargeable battery unit 100, thereby absorbing the heat transmitted from each battery cell 104 to the heat-dissipating section 108. This heat-absorbing member 202 is made of copper (Cu), aluminum (Al), or graphite resin, which generally have high thermal conductivity and flexibility, similar to the heat-absorbing section 106 of the rechargeable battery unit 100. Furthermore, in the example shown in Figure 3, the cooling structure of the power supply unit 200 is arranged on both sides of the heat-dissipating section 108 of the rechargeable battery unit 100 to improve cooling efficiency. The contact side 202a of each cooling structure has a contact point that protrudes towards the heat-dissipating section 108, and in the example shown in Figure 3, for example, it forms a wave shape. By applying such surface processing, the wave shape of the contact side 202a of the flexible heat-absorbing member 202 deforms when in contact, ensuring a sufficient contact area and improving heat absorption. The heat absorbed by the contact side 202a is conducted to the opposite side through the heat-absorbing member 202.

[0048] Specifically, in the first cooling structure example on the right side of Figure 3(a), the contact side 202a of the heat-absorbing member 202 is arranged in parallel with the heat-dissipating section 108, and the opposite side 202b is connected in a vertical and horizontal direction. By pressing the contact side 202a with the opposite side 202b while the wave shape of the contact side 202a is in contact with the heat-dissipating section 108, the wave shape is elastically deformed to ensure a sufficient contact area.

[0049] Furthermore, in the second cooling structure example shown on the left side of Figure 3(a) and in Figure 3(b), the contact side portion 202a of the heat absorption member 202 is arranged in parallel with the heat dissipation portion 108, similar to the example in (a), but the opposite side portion 202b is stacked on the contact side portion 202a as shown in Figure 1(b). Separately, a pressing member 203 is provided to press the contact side portion 202 in the vertical and horizontal directions. This pressing member 203 elastically deforms the wave shape of the contact side portion 202a to secure a sufficient contact area, while the opposite side portion 202b achieves sufficient heat conduction, which is then transferred to the Peltier element plate 204 described later.

[0050] In the example shown in Figure 8, a heat conduction sheet member is laminated (attached) to the copper plate body 202c as the contact side 202a. This heat conduction sheet member 202a flexes when in contact, ensuring a sufficient contact area with the heat dissipation section 108, and conducts heat to the opposite side within the heat absorption member 202. In the example shown in Figure 8, a graphite resin sheet member is laminated (attached) to the copper plate body 202c as the opposite side 202b. This graphite resin sheet member 202b elastically deforms when in contact, ensuring a sufficient contact area, and conducts heat from the heat dissipation section 108 that has been conducted through the copper plate body 202c to the Peltier element plate 204, which will be described later.

[0051] Again, in the example in Figure 3, a Peltier element plate 204 is stacked on the opposite side 202b of the heat-absorbing member 202. A Peltier element is a type of semiconductor used for electronic cooling and heating. When a direct current is passed through it in a certain direction, it absorbs heat (cools) on one side of the element and generates heat (heats) on the opposite side. It is an electronic cooling element that has the property of being able to control the amount of heat absorbed (or generated) by the magnitude of the current. Here, as a cooling structure for the power supply unit 200, the heat-absorbing surface 204a of the Peltier element plate 204 is stacked and in contact with the opposite side 202b of the heat-absorbing member 202. The heat that has been conducted through the heat-absorbing member 202 is absorbed, and that heat is released from the heat-dissipating surface 204b.

[0052] The current flowing through the Peltier element plate 204 is supplied from the power supply 210 via the conductive cable 212, or by dividing the power supplied to the charging outlet 200. By reversing the current flowing through the Peltier element plate 204, the heat-absorbing surface 204a becomes the heat-dissipating surface (and conversely, the heat-dissipating surface 204b becomes the heat-absorbing surface), and it can be used as an electronic heating element for heating, for example, during the initial stages of charging in cold regions or to secure electromotive force.

[0053] Furthermore, a cooling fan 206 is provided on the heat dissipation surface 204b side of the Peltier element plate 204 to provide airflow to the heat dissipation surface 204b. By providing the cooling fan 206 on the heat dissipation side of the Peltier element plate 204, the cooling performance is improved compared to natural heat dissipation in the ambient atmosphere. In order to control the temperature by the power supplied to the Peltier element plate 204 as described later, the operation of the cooling fan is controlled in synchronization with the current supply.

[0054] In the examples shown in Figures 8 and 9, a heat sink 205 for heat dissipation and exhaust is placed between the heat dissipation surface 204b of the Peltier element plate 204 and the cooling fan 206. The heat sink 205 is made of a metal such as copper (Cu) or aluminum (Al) with good heat transfer properties, and is equipped with fins or the like to increase its surface area so that heat can easily escape to the outside air.

[0055] Next, we will outline the charging station 300 in which the cooling structure for the power supply unit 200 is installed, using examples from Figures 5 and 10. First, Figure 5(a) is a schematic diagram of the charging station 300 as seen from the front, and is installed indoors in a convenience store or similar facility equipped with heating and cooling equipment. In this example, the left side of Figure 3(a) and the schematic example in Figure 3(b) are used as the cooling structure for the power supply unit 200. Figure 5(b) is a schematic perspective view showing each charging compartment 304 of the charging station 300 and the state in which the charging battery unit 100 is placed therein, and the example on the right side of Figure 3(a) is used as the cooling structure for the power supply unit 200 (the heat dissipation part 108 of the charging battery unit 100 and the contact side 202a of the heat absorption member 202 of the cooling structure of the power supply unit 200 are omitted from the illustration).

[0056] Furthermore, Figure 10 shows a specific configuration example illustrating how the cooling structure of the power supply unit 200 cools the charging battery units 100 when they are placed in each charging compartment 304 of the charging station 300 schematically shown in Figure 5(b). (a) is a schematic perspective view showing the charging battery units 100 in each charging compartment 304, and (b) is a schematic perspective view showing an example of the installation of the cooling structure of the power supply unit 20 shown in Figure 8 when the charging battery units 100 in the state shown in (a) are being charged.

[0057] First, the charging station 300 illustrated in the schematic diagram of Figure 5 is an integrated housing 302 equipped with multiple charging compartments 304 in which each charging battery unit 100 can be placed horizontally (the upper part of Figure 4 is the front side of Figure 5(b)) and charged. The charging compartments 304 are arranged in a single row of three tiers vertically and are supported on the indoor floor by lower legs 303. Note that the legs 303 may be caster-type with stoppers to allow for easy movement of the installation location indoors.

[0058] Furthermore, each charging compartment 304 is open to the front to allow indoor cool air to enter, and in particular, as shown in Figure 5(b), if the charging battery unit 100 occupies the entire charging compartment 304, the rear may also be opened. When charging the charging battery unit 100, it is inserted from the front of each charging compartment 304, and the charging inlet 116 of the charging battery unit 100 is connected to the charging outlet 208 located at the rear of each charging compartment 304, and charging begins.

[0059] When charging begins, the locking mechanism 306 slides laterally and protrudes from the front input side of the housing 302 of each charging compartment 304, preventing the charging battery unit 100 from flying out during charging. When charging is complete, it slides back out towards the housing 302, allowing the charging battery unit 100 to be removed.

[0060] Furthermore, the heat-absorbing member 202, Peltier element plate 204, and cooling fan 206, which serve as the cooling structure for the power supply unit 200, are inserted through the side of the housing 302 of each charging compartment 304 in both cases shown in Figures 5(a) and (b). The heat-absorbing member 202 is inserted on the inside and the cooling fan 206 on the outside, and the heat-absorbing member 202 is cooled by contacting the heat dissipation section 108 of the charging battery unit 100. The current supplied to the Peltier element 204 and the cooling fan 206 may be supplied directly from a separate, independent external power source. However, in practice, as will be described later with reference to Figure 7, power is supplied to the locking mechanism and Peltier element plate 204, etc., in synchronization with the start of charging. Therefore, power is supplied by splitting the power supply path from the external power source to the charging outlet 208.

[0061] Furthermore, as an example of the actual configuration of the cooling structure for the charging battery unit 100 and the power supply unit 200 within each charging compartment 304 as described above, a slide guide 308 having a frame portion 308a with the battery insertion side open at its bottom is provided in each charging compartment 304, as shown in Figure 10(a). When the charging battery unit 100 is inserted horizontally into the charging compartment 304 from the front, the lower sides of both sides of the charging battery unit 100 fit into the frame portion 308a (not shown) and slide back and forth (see arrow A in Figure 10(b)). A gripping member 102f is attached to the front side (top surface in Figure 4) of the charging battery unit 100, making it easy to hold the charging battery unit 100 and easy to insert into the slide cover 308.

[0062] Furthermore, when the rechargeable battery unit 100 is inserted, it is guided along the slide cover 308 to the back of the charging compartment 304, and the rear frame portion 308a acts as a stopper to position it in the front-to-back direction, making it ready for charging. At this time, the cooling window portion 102f, which is an opening that penetrates the lower part of the battery case 102 (the lower side in Figure 4), is positioned at the installation location of the cooling structure of the power supply unit 200 so that the heat dissipation portion 108 of the rechargeable battery unit 100 is exposed (see Figure 10(b)). As a result, as charging begins, the cooling structure and the heat dissipation portion 108 begin to cool each battery cell 104.

[0063] As shown in Figure 10(b), the cooling structure of the power supply unit 200 is provided with clampers 309 that are attached to both the left and right ends, crossing the vicinity of the top surface of the charging battery unit 100 which is placed horizontally in the charging compartment 304. These clampers 309 tighten the cooling structures at both ends in a direction that clamps the charging battery unit 100 from both sides (in the direction of arrow B in Figure 10(b)), bringing the heat-absorbing member 202 into contact with the heat-dissipating part 108 exposed from the cooling window part 102f, thereby enabling highly efficient conduction of heat from each battery cell 104.

[0064] Next, the connection between the charging inlet 116 of the charging battery unit 100 and the charging outlet 208 of the power supply unit 200 will be explained with reference to Figure 6. Figure 6(a) is a simplified perspective view of the charging battery unit 100 as seen from below (below Figure 4), showing the charging inlet 116 installed inside the bottom 102b of the battery case 102 shown in Figure 4. Figure 6(b) shows a perspective photograph (top), a side view (bottom left), and a plan view of the connection side (bottom right) of the charging outlet 208 of the power supply unit 200. Figure 6(c) shows a perspective photograph (top), a side view (bottom left), and a plan view of the connection side (bottom right) of the charging inlet 116 of the charging battery unit 100.

[0065] The charging inlet 116 of the rechargeable battery unit 100 has its casing 116d mounted inside the base portion 102b of the battery case 102, with the connection side to the power supply unit 200 forming two cylindrical members that protrude in parallel. Each cylindrical member of the casing 116d is a hollow hole, and a flexible hollow connection terminal 116a is provided on its inner wall. The surface of this connection terminal 116a is coated with a copper (Cu) film to electrically connect to a conductive cable (not shown). Furthermore, its tip protrudes from the casing 116d as shown in the lower left of Figure 6(c), and is connected to a conductive cable 118 (see Figure 4) to each battery cell 104. In addition, the casing 116d has four through holes between the bases of the two cylindrical members, and signal terminals 116c for sending and receiving control signals are provided on its inner wall. Similar to the connection terminal 116a, this signal terminal 116 is coated with copper (Cu) to electrically connect to the control board 120 (see Figure 4), and its tip protrudes from the casing 116d as shown in the lower left of Figure 6(c).

[0066] Furthermore, the charging outlet 208 of the power supply unit 200 has a casing 208b on the connection side that forms an opening, and a connection terminal 208a is arranged in parallel inside the opening, forming a cylindrical projection that can be inserted into the hole 116b having the connection terminal 116a of the charging inlet 116. Therefore, when the opening side of the casing 208b of the charging outlet 208 is placed over the cylindrical member of the casing 116a of the charging inlet 116, the connection terminal 208a of the charging outlet 208 is guided into the connection terminal 116a of the charging inlet 116 and electrically connected. In order to ensure that the connection terminals 208a and 116a are firmly in contact and that the electrical connection is maintained, methods such as making the connection terminal 208 tapered and elastically deforming it within the connection terminal 116a to ensure contact are employed, or fixing the connection state between the connection terminals 208a and 116a using a separate detachable means such as a hinge toggle.

[0067] Furthermore, a signal terminal 208c is provided inside the opening of the casing 208b between the two connection terminals 208a for sending and receiving signals to and from the signal terminal 116c of the charging inlet 116. The connection terminals 208a and the signal terminal 208c are also coated with copper (Cu), similar to the charging inlet 116 connection terminals 116a and signal terminal 116c described above.

[0068] Next, we will illustrate and explain the control flow when charging a battery unit 100 by connecting it to a power supply unit 200 in a charging station 300 as shown in Figures 5 and 10, with reference to Figure 7.

[0069] The charging station 300 monitors in real time the amount of current supplied to the charging battery unit 100 by the power supply unit 200 during charging, and monitors the power supply and charging amount to the cooling structure of the charging battery unit 100 and the power supply unit 200 (STEP 10). This monitoring utilizes CAN network (Controller Area Network) communication.

[0070] First, when the charging battery unit 100 is placed in the charging compartment 304 of the charging station 300, and the charging inlet 116 of the charging battery unit 100 is connected to the charging outlet 208 of the power supply unit 200, if the power supply to the charging battery unit 100 is monitored by STEP 10 and it is determined that the connection between the charging inlet 116 and the charging outlet 208 is good, the locking mechanism 306 closes the charging compartment 304. The opening and closing of this locking mechanism 306 is also monitored by the CAN network communication described above (STEP 10), but the closing method may be manually performed by the user as described above and the closing may be a condition for starting charging, or it may be automatically closed on the condition that the connection is good.

[0071] When the closure of the charging compartment 304 by the locking mechanism 306 is confirmed (STEP 14), charging of the charging battery unit 100 from the power supply unit 200 begins, power is supplied, and at the same time, a charging indicator lamp (charging completion indicator means), not shown, is illuminated (STEP 16).

[0072] As soon as charging begins, power may be supplied to the Peltier element plate 204 and the cooling fan 206 to cool the heat-generating areas of each battery cell 104 from the heat dissipation section 106 of the charging battery unit 100. However, Figure 7 illustrates a control configuration in which cooling occurs when the measured value t of the heat-generating area becomes hotter than the ideal temperature ta. Specifically, first the ideal temperature ta of the heat-generating area is calculated (STEP 18). The ideal temperature ta may be set (calculated) from an upper threshold of a predetermined temperature set by the manufacturer of each battery cell 104, or the current temperature that does not reach the upper threshold may be calculated as the ideal temperature ta based on the heat generation profile over time calculated from the amount of supplied power monitored in STEP 10.

[0073] Once the ideal temperature ta is calculated (STEP 18), the temperature of the heat-generating area of ​​the battery cell 104 is measured and set as the measured temperature t (STEP 20). If the calculated ideal temperature ta is greater than or equal to a predetermined value compared to the measured temperature t, the Peltier element plate 204 is energized and the cooling fan 206 is activated to cool the heat-generating area of ​​the battery cell 104 (STEP 22-STEP 24). Once the heat-generating area has cooled and the ideal temperature ta is less than the predetermined value compared to the measured temperature t, the power to the Peltier element plate 204 and the operation of the cooling fan 206 are stopped (STEP 22-STEP 26).

[0074] Then, when the charging of the rechargeable battery unit 100 is complete, the power supply is stopped and charging ends, and at the same time, the aforementioned charging indicator lamp (charging completion indicator means) turns off or the charging completion indicator lights up (STEP28~STEP30). At the same time, the lock mechanism 306 releases the closure of the charging compartment 304 (STEP32), and the charging inlet 116 is removed from the charging outlet 208 to take out the charged rechargeable battery unit 100 from the charging compartment 304.

[0075] Although various embodiments of the present invention have been described above, the embodiments shown in this specification and drawings are merely examples of the present invention, and it will be obvious to those skilled in the art that various other improvements and modifications exist based on the concept and teachings of the claims. [Explanation of symbols]

[0076] 100 Rechargeable Battery Units (Fast Charging Battery Units) 102 Battery Case 102a Battery mounting space 102b Hem 102c connection space 102d Fixed part 102e Cooling window section 102d Gripping member 104 battery cells 104a anode 104b Cathode 104c bag body 106 Heat absorption section 106a Edge 108 Heat radiation part 110 Heat absorption / radiation means 114 Bus Bar 116 Charging inlet 116a Connection terminal 116b Hole 116c signal terminal 116d Casing 118 Conductive cable (connection part) 120 Control board 200 Power supply unit 202 Heat-absorbing component (contact part for heat conduction) 202a Contact side (battery unit side surface (thermal conductive sheet member)) 202b Opposite side (Peltier element plate side surface (graphite resin sheet material)) 202c copper plate body 203 Pressing member 204 Peltier element plate 204a Endothermic surface 204b Heat dissipation surface 205 Heatsink 205a Ventilation opening 206 Cooling Fan 207 Insulation and condensation prevention cover 208 Charging Outlet 208a Connection terminal 208b Casing 208c signal terminal 210 Power supply 212 Conductive Cable 300 charging stations 302 enclosures 303 Legs 304 Charging area 306 Locking mechanism (locking means) 308 Slide Guide 308a Frame 309 Clamper

Claims

1. Multiple rechargeable sheet-like battery cells are arranged in parallel, and their positive and negative terminals are connected in series / parallel with conductive busbars to form a sealed battery case. In the charging region of each of the aforementioned battery cells, a plate-shaped heat absorption / dissipation means made of copper, aluminum, or graphite resin is positioned, having a heat absorption portion interposed in a layered parallel manner between the outer surfaces of each of the aforementioned battery cells and / or arranged in parallel on the outer surface of the outermost battery cell, and a heat dissipation portion connected to the edge of the heat absorption portion and exposed to the outside. A rapid charging battery unit equipped with [feature name / feature].

2. The rapid charging battery unit according to claim 1, wherein each of the aforementioned battery cells is a rechargeable battery capable of rapid charging at 1.0C or higher, and they are connected in series / parallel within the battery case.

3. An indoor-installable charging station capable of charging the rapid-charging battery unit described in claim 1 or 2, The aforementioned rapid-charging battery unit is detachably mounted as a power source for an electric light vehicle, and is connected to a busbar that connects the terminals of each battery cell so that it can be charged via a charging inlet from an external AC power source. The charging inlet is equipped with a control board that has an AC / DC converter and controls the power supply to the busbar. The charging station is It consists of a single housing equipped with multiple charging compartments, each having a charging outlet for the rapid charging battery unit that connects to an external AC power source. Each charging compartment can be positioned inside with the rapid charging battery unit having an externally exposed portion. A charging station in which a power supply unit capable of cooling each battery cell of a charging battery unit is installed in each charging compartment, and the power supply unit is connected to a charging outlet for the rapid charging battery unit or to an external power source separately.

4. Each charging compartment of the housing is provided with a charging management means for monitoring the supply of power from the charging outlet to the rapid charging battery unit, the charging management means has a locking means that closes or partially closes from an open state on the indoor space side when the charging inlet of the rapid charging battery unit is connected to the charging outlet in the charging compartment and power is supplied to the rapid charging battery unit from an external power source, and when the power supply to the rapid charging battery unit is completed, the charging completion indicator means displays a charging completion indicator and executes control to release the locking means, as described in claim 3.

5. The rapid charging battery unit has a battery case as an enclosure, which has a battery mounting space on one side for sealing and housing a plurality of the battery cells arranged in parallel and connected to each other by busbars, and a base portion that extends to the other side of the battery mounting space and is open to the outside at the other end to guide connection to an external power supply unit. The battery mounting space and the lower part are separated by a fixing portion, The charging station according to claim 3 or 4, wherein the fixed portion is fitted with a control board connected to the busbar to perform power supply control to the battery cell, and a charging inlet connected to the control board to receive a charging outlet from an external power source inside the base portion and supply power to the external power source.

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