JP3986242B2 - Battery system for electric vehicles - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a battery system for an electric vehicle, and more particularly to an electronic control unit constituting the battery system using a cooling fan for cooling the battery and an electric vehicle battery system for cooling an electrical component.
[0002]
[Prior art]
In an electric vehicle, a battery for supplying power to the traveling motor, an electrical component including a detection component for detecting a charging / discharging current of the battery, a remaining capacity (SOC) of the battery, and the like are calculated. An electronic control unit (ECU) including a microcomputer for mounting is mounted. And since these batteries, electrical components, and ECU generate heat as the electric vehicle travels, it is necessary to cool them with cooling air supplied from a cooling fan.
[0003]
For example, ECUs generate heat and heat in parts such as circuit power supplies, and the temperature in the housing (box) that houses them rises. This causes temperature drift of other related parts such as microcomputers, resulting in functionality and reliability. It is a factor that makes it worse.
[0004]
In addition, electrical components also have a rise in temperature of the main cable, relay, and current sensor when energized, which is a factor that deteriorates reliability. In particular, the current sensor has a temperature drift, which can be a factor of deteriorating functionality such as current detection accuracy. Therefore, higher reliability is ensured by using more expensive parts.
[0005]
[Problems to be solved by the invention]
By the way, in order to ensure functionality and reliability, if the battery, the electrical component, and the ECU are cooled by individual cooling fans, there is a problem that the number of fans is required, the structure is complicated, and the cost is high. In addition, there is a problem that the cost of parts increases when expensive parts are used to ensure high reliability.
[0006]
SUMMARY OF THE INVENTION Therefore, a main object of the present invention is to provide an electric vehicle battery system capable of efficiently cooling an inexpensive electrical component and ECU with a simple configuration by using a battery cooling fan.
[0007]
[Means for Solving the Problems]
The present invention provides a battery configured by connecting a plurality of secondary battery cells in series, an electrical component including a detection component for detecting a charge / discharge current of the battery, and a detection signal from the detection component. In an electric vehicle battery system comprising an electronic control unit (ECU) including a microcomputer for calculating the remaining capacity of the battery and an air cooling circuit for cooling the battery, the battery system is housed in an entire housing having an air inlet. And the air cooling circuit includes a cooling air branching means for branching the cooling air flowing from the intake port to at least one of the battery and the electronic control unit or the electrical component. System.
[0008]
[Action]
For example, since the electrical components and the cooling air passages of the ECU can be arranged in the air cooling circuit of the battery, the configuration is simplified and cooling can be performed effectively.
[0009]
【The invention's effect】
According to the present invention, by using a battery air-cooling circuit, it is possible to reduce unnecessary temperature rise and to adopt low-cost parts and improve reliability.
[0010]
The above object, other objects, features, and advantages of the present invention will become more apparent from the detailed description of the embodiments given below with reference to the drawings.
[0011]
【Example】
FIG. 1 is a circuit block diagram showing the overall configuration of an electric vehicle battery system according to an embodiment of the present invention.
[0012]
In FIG. 1, a battery system 10 for an electric vehicle includes a battery 12 as a power source, relay contacts 18a and 18b of a main relay 18 provided between a positive terminal lead wire 14 and a negative terminal lead wire 16 of the battery 12, Series circuit 24 of precharge relay 20 and precharge resistor 22 connected in parallel to relay contact 18a, charge / discharge current detected by current sensor 26, battery temperature and battery voltage detected by temperature sensor (not shown), etc. As an input, the remaining capacity (SOC) of the battery 12 is calculated and an electronic control unit 28 (hereinafter simply referred to as “ECU”) including a microcomputer for calculating the temperature difference based on the battery temperature and the outside air temperature and the temperature difference calculated by the microcomputer Based on the control signal output from the ECU 28, the cooling fan It includes a fan drive circuit 32 for driving the 0. The ECU 28 also outputs necessary control signals to the main relay 18 and the precharge relay 20. The fan drive circuit 32 includes a relay 32a and a driver 32b, both of which are controlled by signals from the ECU 28.
[0013]
A traveling motor 36 is connected between the positive terminal lead 14 and the negative terminal lead 16 of the battery 12 via an inverter 34 that converts the frequency of direct current into alternating current.
[0014]
The battery 12 is configured by connecting two battery modules 12A and 12B in series with a fuse 38 interposed therebetween. Each of the battery modules 12A and 12B is, for example, a battery in which 120 1.2V nickel metal hydride batteries are connected in series to 144V, and as a power source, the two battery modules are connected in series to 288V.
[0015]
FIG. 2 shows main components of the electric vehicle battery system 10 cooled by the cooling fan 30 described above, that is, electrical components and microcomputers including detection components such as the battery 12 and the current sensor 26, the main relay 18, the fan drive circuit 32, and the like. It is a planar illustration figure which shows the arrangement configuration of ECU28 including this.
[0016]
In FIG. 2, for example, a battery pack 42 including a battery 12 composed of two battery modules 12A and 12B is arranged at the center of the inside of a component storage case 40 formed of plastics, and left and right spaces on both sides thereof. The ECU 28 and the electrical components are arranged in a state of being housed in boxes 44 and 46, respectively. An air inlet 48 and an air outlet 50 of the cooling fan 30 are formed in the front wall 40a and the rear wall 40b of the component storage case 40, respectively. When the cooling fan 30 is activated, the cooling air flows in the wind direction indicated by the arrow. Flowing.
[0017]
As shown in FIG. 3, components of the ECU 28 are arranged on a circuit board 52 described later, and connectors 56 for connecting cables (harnesses) 54 are provided at both ends of the circuit board 52. Each box 44, 46, for example, the box 44 that houses the ECU 28, is provided with a gap 60 that communicates with the cooling air passage 58 of the component storage case 40 in which the battery pack 42 is disposed.
[0018]
That is, at the four corners formed by the component storage case 40 and the battery pack 42, a part of the cooling air flowing into the central portion of the component storage case 40 from the intake port 48 of the front wall 40a branches to the left and right by the partition plate 43. Cooling air inlets 62 and 62 flowing into the left and right space portions of the component storage case 40, and a cooling air flow that allows the cooling air flowing into the left and right space portions to flow out to the exhaust port 50 provided in the rear wall 40b of the component storage case 40 Outlets 64 and 64 are provided on the left and right, respectively.
[0019]
4 to 6 are a perspective view and a cross-sectional view of the main part in a state where the ECU 28 is housed in the box 44. FIG. The positional relationship between the box 44, the component 51 including the microcomputer of the ECU 28, the circuit board 52, the connector 56, the cable (harness) 54 and the gap 60, the flow of cooling air (flow of wind), etc. Can be clearly understood.
[0020]
7 to 9 are a perspective view and a cross-sectional view of the main part in a state where each electrical component 27 such as a current sensor is housed in a box 46, for example. The positional relationship among the box 46, each electrical component 27, the cable (harness) 54, and the gap 60 described before each of these drawings, the flow of cooling air (wind flow), and the like can be clearly understood.
[0021]
In addition, each box 44 and 46 arrange | positioned in the component storage case 40 by letting the wind (cooling air) which penetrate | invaded into the inside from the clearance gap 60 of each box 44 and 46 to the inside of ECU28 or the electrical component 27 comes from the inside and outside. The air cooling effect is further improved by cooling. Further, if necessary, holes may be provided on the side surfaces of the boxes 44 and 46 to allow air to flow in.
[0022]
As described above, according to the present invention, since the air cooling circuit cools at least one of the electrical component and the ECU, the electrical component and the ECU component are cooled by the cooling fan that cools the battery with a simple configuration. Thus, the reliability can be improved and an efficient system can be realized at a low cost.
[Brief description of the drawings]
FIG. 1 is a circuit block diagram showing the overall configuration of an electric vehicle battery system according to an embodiment of the present invention.
2 is a schematic plan view showing an arrangement configuration of main components in FIG. 1; FIG.
FIGS. 3A and 3B are a plan view illustrating the relationship between the ECU and the box in FIG. 2 and a left and right side view thereof.
FIG. 4 is a perspective view of a state in which ECU components are housed in a box.
5 is a cross-sectional view of the main part in FIG. 4. FIG.
6 is a cross-sectional view of the main part in FIG. 4. FIG.
FIG. 7 is a perspective view of each electrical component stored in a box.
FIG. 8 is a cross-sectional view of a main part in FIG.
9 is a longitudinal sectional view of the main part in FIG. 7. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Electric vehicle battery system 12 ... Battery 12A, 12B ... Battery module 26 ... Current sensor (detection component)
28 ... Electronic control unit (ECU)
30 ... Cooling fan 40 ... Parts storage case (whole housing)
44, 46 ... Box (housing)

Claims (3)

A battery configured by connecting a plurality of secondary battery cells in series; an electrical component including a detection component for detecting charge / discharge current of the battery; and at least a remaining battery in response to a detection signal from the detection component In an electric vehicle battery system comprising an electronic control unit including a microcomputer for calculating a capacity, and an air cooling circuit for cooling the battery,
The battery system is housed in an entire housing having an air inlet, and the air cooling circuit is a cooling air branching unit that branches cooling air flowing from the air inlet into at least one of the battery and the electronic control unit or the electrical component. equipped with a,
The battery system for an electric vehicle, wherein the cooling air branching means is formed by branch holes provided in a partition plate at four corners formed by the whole casing and the battery.   The electronic control unit is housed in a housing, a cooling air passage is provided in the housing, and the cooling air branched by the cooling air branching unit flows through the cooling air passage. The battery system for electric vehicles as described. The electrical equipment is housed in a housing, wherein the housing the cooling air passage is provided, according to claim 1-2, characterized in that flowing cooling air branched by the cooling air branching means to the cooling air passages The battery system for electric vehicles described in 1.

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