JPH11178231A - Temperature control device for assembled batteries for electric vehicles - Google Patents

Abstract

(57) [Problem] To provide a temperature management device for an assembled battery for an electric vehicle, in which the safety is improved by fine temperature management of a high-voltage assembled battery and the usability is improved. A plurality of battery temperature sensors provided in an assembled battery having a large number of unit cells housed in a common battery case are provided, the temperature of each unit is finely monitored, and the temperature of each unit cell is monitored. Anomalies are monitored as closely as possible. When only one of the battery temperature sensors has a low temperature resistance value corresponding to a temperature lower than the remaining battery temperature sensor by a predetermined temperature or more (S
102) Assuming that the battery is not abnormal but the sensor is abnormal, the output of this sensor is ignored and charging and discharging are permitted. That is, the fact that only one battery is at a low temperature inside the same battery case does not cause any problem even if charging and discharging are continued as it is. Further, in the present invention, when a part of each battery temperature sensor has a high temperature resistance value corresponding to a temperature higher than a remaining battery temperature sensor by a predetermined temperature (normal variation range) or more (S106, S108), It is determined that the battery temperature is abnormal, and charging and discharging of the battery is prohibited (S11).
4).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a temperature control device for an assembled battery for an electric vehicle.

[0002]

2. Description of the Related Art In a conventional battery pack for an electric vehicle, a temperature sensor is used to monitor the battery temperature with high precision for safety measures and performance management. Charging and discharging are immediately prohibited. On the other hand, in an assembled battery for an electric vehicle, an ultra-high voltage of 300 V or 400 V or more has been studied due to a demand for reduction of wiring loss and miniaturization of an element for switching charging / discharging current.

[0003]

However, in such a high-voltage assembled battery, since 250 or more or 300 or more cells are connected in series, the battery case for accommodating the assembled battery must be large. . In particular, the battery case tends to be further enlarged with the progress of increasing the capacity of the unit cell. For this reason, since the temperature difference between each part inside the battery case becomes large, it becomes necessary to monitor the temperature environment of each battery by distributing a large number of temperature sensors in each part inside the battery case.

However, in order to monitor the temperature of each of a large number of cells in detail, it is necessary to provide a large number of temperature sensors, if not the same as the number of the cells. If any of them becomes abnormal, the probability of outputting a signal voltage corresponding to abnormally low temperature or abnormally high temperature increases, and in this case, charging and discharging of the battery is prohibited as well as abnormal temperature inside the battery case, There was a problem that driving was prohibited.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a temperature control device for an assembled battery for an electric vehicle, in which the safety is improved by careful temperature management of the high-voltage assembled battery and the usability is improved. That is the problem to be solved.

[0006]

According to the battery management apparatus for an assembled battery for an electric vehicle according to the present invention, an assembled battery in which a large number of cells are housed in a common battery case. A large number of battery temperature sensors are provided therein, and the temperature of each unit is monitored in detail, and the abnormal temperature of each cell is monitored as closely as possible.

[0007] In particular, in the present invention, when only one of the battery temperature sensors has a low temperature resistance value corresponding to a temperature lower than the remaining battery temperature sensor by a predetermined temperature or more, the battery is not abnormal but the sensor is abnormal. If there is, the charge / discharge is permitted ignoring the output of this sensor. That is, the fact that only one battery is at a low temperature inside the same battery case does not cause any problem even if charging and discharging are continued as it is.

Further, according to the present invention, when a part of each battery temperature sensor has a high temperature resistance value corresponding to a temperature higher than a remaining battery temperature sensor by a predetermined temperature (normal variation range) or more, the battery temperature sensor may be used. Battery charging and discharging is prohibited. Eventually, when monitoring the temperature of each part in the battery case using a large number of battery temperature sensors, some batteries actually become abnormally high temperature only when the temperature of some sensors is higher than the temperature of the remaining many sensors. The present invention has been made by paying attention to the fact that there is a danger that charging and discharging do not need to be prohibited at other temperature variations. As a result, unnecessary prohibition of charging and discharging can be avoided, so that the usability of a device using this battery, for example, an electric vehicle can be greatly improved.

Of course, even when many sensors output a high temperature higher than a predetermined temperature than some sensors, or even when all sensors output a high temperature higher than a predetermined temperature, If many or all temperatures are above a predetermined absolute temperature, charging and discharging should, of course, be prohibited. The configuration according to claim 2 further notifies the temperature control device for an assembled battery for an electric vehicle according to claim 1 when it is determined that the battery temperature sensor is abnormal and when it is determined that the battery temperature is abnormal, The driver can easily discriminate between a sensor and a battery.

According to a third aspect of the present invention, in the temperature control apparatus for an assembled battery for an electric vehicle according to the first aspect,
If only one of the battery temperature sensors has an abnormally high temperature resistance value corresponding to a temperature higher than the predetermined temperature than the remaining battery temperature sensors, it is determined that the battery temperature sensor is abnormal, and charging and discharging of the battery is permitted. That is, if some of the temperature sensors described above are higher than the remaining more temperature sensors by more than the variation range, charging / discharging is prohibited in consideration of the possibility of a battery abnormality, but the output of one temperature sensor is When an abnormally high temperature resistance value corresponding to an extreme temperature exceeding the temperature at which a battery normally occurs (for example, 100 ° C. or higher) is output, this is a sensor abnormality such as a disconnection or a short circuit, unless many other nearby sensors are so. It is clear that this is the case, and it can be determined that the sensor is abnormal, and it is possible to avoid useless prohibition of charging and discharging.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the following examples. However, the present invention is not limited to the configuration of the following embodiment, and it is obvious that the present invention can be configured using a replaceable known circuit.

[0012]

Embodiment 1 An embodiment of a battery management apparatus for an assembled battery for an electric vehicle according to the present invention will be described with reference to FIG. Reference numeral 1 denotes an assembled battery serving as a main battery for supplying power to a traveling motor of an electric vehicle. The assembled battery is constituted by connecting several hundred cells connected in series to each other in series and housed in a battery case 10.

Reference numeral 2 denotes a charging / discharging control device for controlling charging / discharging of the battery, which comprises a DC / DC converter and an inverter.
To control the discharge to. Reference numeral 4 denotes a microcomputer-type battery management device that monitors the battery, and monitors the battery temperature based on temperature signals from a total of nine battery temperature sensors 51 to 59 that are distributed and arranged at various parts in the battery case 10.

The management operation of the battery management device 4 will be described with reference to the flowchart of FIG. First, a total of nine temperatures t1 to t9 are read from the battery temperature sensors 51 to 59 (S100), and whether only one of the temperatures t1 to t9 is lower than the others by a predetermined temperature difference ΔT (here, 20 ° C.) or more is determined. It is checked whether it is (S102), and if so, the abnormality of the temperature sensor that outputs the low temperature is warned (S104), and the process proceeds to S112. On the other hand, if not in S102, S106
Proceed to.

In S106, any one of the temperatures t1 to t9 is set to a predetermined absolute high temperature tHH (here, 100
° C) or higher, and if so, whether it is only one (S108), and if so, it should not be possible in reality that only such one would be such an ultra-high temperature tHH. And this ultra-high temperature tHH
(S11).
0), and proceed to S112. On the other hand, if a plurality of sensors output such an ultra-high temperature tHH in S108, charging / discharging of the main battery 1 is prohibited for safety (S11).
4).

In step S112, among the temperatures t1 to t9,
Some of the battery temperature sensors 51 to 59 that have not been determined to be abnormal in S102 and S108 described above have a predetermined temperature difference ΔT (here, 2
0 ° C.) or higher, and if so, it is determined that such a high temperature is due to abnormal heat generation of the battery, and S1
Proceed to 14 to prohibit charging and discharging of the main battery 1 for safety.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a battery management device for an assembled battery for an electric vehicle according to the present invention.

FIG. 2 is a flowchart showing a detection voltage check operation of the ECU of FIG. 1;

[Explanation of symbols]

1 is an assembled battery as a main battery, 4 is a microcomputer type battery management device (signal processing unit), 10 is a battery case (case),
51 to 59 are battery temperature sensors.

Claims (3)

[Claims] 1. A plurality of battery temperature sensors provided in an assembled battery containing a number of cells connected in series and / or in a common case, and an output of each of the battery temperature sensors. A signal processing unit that processes a signal, wherein the signal processing unit has a low temperature resistance value corresponding to a temperature lower than a predetermined temperature by at least one of the remaining battery temperature sensors, The signal of the battery temperature sensor having the low temperature resistance value is determined to be abnormal and charging and discharging of the battery is permitted, and a part of each battery temperature sensor is at least a predetermined temperature higher than the remaining battery temperature sensors. A temperature management device for an assembled battery for an electric vehicle, wherein when the battery has a high temperature resistance value corresponding to a high temperature, it is determined that the battery temperature is abnormal and charging and discharging of the battery are prohibited. 2. The temperature management device for an assembled battery for an electric vehicle according to claim 1, wherein the signal processing unit determines whether the battery temperature sensor is abnormal or the battery temperature is abnormal. Temperature control device for an assembled battery for an electric vehicle. 3. The temperature control device for an assembled battery for an electric vehicle according to claim 1, wherein the signal processing unit is configured to set the temperature of only one of the battery temperature sensors to be higher than the predetermined temperature than the remaining battery temperature sensors. A temperature management device for an assembled battery for an electric vehicle, wherein when the battery has a corresponding abnormally high temperature resistance value, the battery temperature sensor is determined to be abnormal and charging and discharging of the battery are permitted.