Car battery abnormality detection device

Abstract

The present invention provides an abnormality detection device for automobile batteries that uses the AE method to detect abnormalities in automobile batteries before they are destroyed, thereby preventing battery destruction in advance. [Solution] The automobile battery abnormality detection device 1 is equipped with an AE sensor 3 as a detection unit that detects abnormalities in the EV battery 2, and the AE sensor 3 is fixed to the outer peripheral surface 5a of the main body case 5 of the EV battery 2. The AE signal detected by the AE sensor 3 is processed by a signal processing unit 4 to detect the occurrence of cracks, which are a precursor to destruction of the EV battery 2.

Description

[Technical field]

[0001] The present invention relates to an abnormality detection device for an automobile battery, and more specifically to a battery abnormality detection technology that detects abnormalities in an automobile battery such as an EV battery and prevents the automobile battery from being destroyed. [Background technology]

[0002] Recently, there have been a number of fires involving electric vehicle (EV) batteries, including a fire at a battery production factory for EVs, resulting in numerous deaths and injuries, and an EV bursting into flames.

[0003] This is because the lithium batteries (EV batteries) installed in EVs use flammable solvents as electrolytes, meaning that the risk of fire cannot be reduced to zero, and if the battery is subjected to a strong impact, it is prone to short circuits and fire.

[0004] Considering the flammability of EV batteries that use the above electrolytes, solid-state batteries, such as semi-solid and solid-state batteries, in which the electrolyte is solid, have been developed. In addition, non-flammable EV batteries have also been developed, reducing the possibility of fire.

[0005] However, when these EV batteries (solid-state batteries and lithium batteries) are actually installed in automobiles and used continuously as on-board batteries, there is a risk that the batteries may crack due to overheating, expansion, shock, etc. while the car is in operation.

[0006] If a crack occurs in the battery, the internal structure of the battery may be destroyed, resulting in a fire and endangering passengers, particularly the driver, due to a battery destruction accident.

[0007] This risk is particularly serious in the drive batteries of EVs, which use large-capacity lithium-ion batteries. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2006-017640 A Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention has been made in consideration of the above-mentioned problems in the conventional technology, and its purpose is to provide an abnormality detection device for automobile batteries that uses the AE method to detect abnormalities in automobile batteries before they are destroyed, thereby preventing battery destruction. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, the abnormality detection device for an automobile battery of the present invention is characterized in that it comprises an AE sensor as a detection unit for detecting abnormalities in the automobile battery, and this AE sensor is installed and fixed to the outer peripheral surface of the main body case of the battery, and the AE signal detected by the AE sensor is processed in a signal processing unit to detect the occurrence of cracks, which are a precursor to destruction of the battery.

[0011] As a preferred embodiment, the following configuration is adopted. (1) The signal processing section includes a preamplifier, a waveform analyzer, a frequency analyzer, a discriminator, a determiner, and a detection signal output section.

[0012] (2) The above-mentioned automotive battery is an EV battery. Effect of the Invention

[0013] The car battery anomaly detection device of the present invention is equipped with an AE sensor as a detection unit that detects abnormalities in the car battery. This AE sensor is installed and fixed to the outer peripheral surface of the main body case of the battery. The AE signal detected by the AE sensor is processed in a signal processing unit to detect the occurrence of cracks, which are a precursor to destruction of the battery. As a result, unique effects are obtained as shown below, and by using the AE method to detect abnormalities in the car battery before it is destroyed, it is possible to provide an car battery anomaly detection device that prevents battery destruction in advance.

[0014] In other words, an AE sensor is provided as a detection unit for detecting abnormalities in an automobile battery, and this AE sensor is installed and fixed to the outer peripheral surface of the main body case of the battery. Therefore, the occurrence of cracks, which are a precursor to destruction of the battery, can be detected as AE waves (acoustic emission waves), and by processing the AE signal, destruction of the battery can be detected in advance.

[0015] This makes it possible to prevent accidents involving destruction or other problems with the automobile battery, and ensures the safety of passengers, especially the driver, who is most exposed to risk. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic diagram showing an EV battery abnormality detection device according to one embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals denote the same components or elements.

[0018] FIG. 1 shows an anomaly detection device for an EV battery according to the present invention. Specifically, this anomaly detection device 1 is connected to an EV battery 2 actually mounted in an electric vehicle (EV) (not shown) and detects anomalies in this EV battery 2 prior to breakdown by the AE method. The device mainly comprises an AE sensor 3 which is a detection unit, and a signal processing unit 4 which processes the AE signal from this AE sensor 3.

[0019] EVs are equipped with two types of batteries: a drive battery and an auxiliary battery. The former drive battery supplies the electricity for the EV to run and is made up of large-capacity lithium-ion batteries. The latter auxiliary battery supplies electricity to the EV's electrical equipment, such as turning on the lights, audio equipment, and power windows, and provides 12V DC electricity, just like in gasoline engine vehicles.

[0020] The EV battery 2 in this embodiment is a driving battery that uses a large-capacity lithium-ion battery, and is composed of a solid-state battery or a lithium battery.

[0021] The AE sensor 3 functions as a detector that detects abnormalities in the EV battery 2, and detects elastic waves (ultrasonic waves) called AE (Acoustic Emission) waves.

[0022] The EV battery 2 may develop cracks due to overheating, expansion, shock, etc. while the vehicle is in operation. When a crack occurs, AE waves are emitted from the cracked area, and this phenomenon is detected by the AE sensor 3.

[0023] Furthermore, the above-mentioned AE waves are generated by tiny cracks that are in the early stages of deterioration, well before the EV battery 2 is completely damaged, so by detecting the time when these cracks occur, it is possible to detect the signs of destruction of the EV battery 2.

[0024] For this purpose, the AE sensor 3 is installed and fixed to the main body case 5 of the EV battery 2, specifically, it is adhesively fixed to any location on the outer circumferential surface 5a of the main body case 5 with an epoxy adhesive or the like. Therefore, the abnormality detection device 1 of this embodiment equipped with the AE sensor 3 can be easily installed and applied to the existing EV battery 2 after it has been mounted on the EV.

[0025] The specific configuration of the AE sensor 3 is conventionally known, and a detailed description thereof will be omitted, and a commercially available sensor can be used.

[0026] The signal processing unit 4 is composed of an electronic circuit that processes the AE signal detected by the AE sensor 3, and has as its main components a pre-amplifier 6, a waveform analyzer 7, a frequency analyzer 8, a discriminator 9, a judgement unit 10 and a detection signal output unit 11.

[0027] The specific configuration of the signal processing unit 4 is conventionally known, similar to the AE sensor 3, and a detailed description thereof will be omitted.

[0028] In the signal processing unit 4, since the EV battery 2 mounted on the EV is constantly subjected to vehicle noise and vibration while the vehicle is in operation, the AE waves caused by these are distinguished from those and only specific AE waves caused by the occurrence of cracks, etc. are extracted and processed for signal processing. First, the AE wave signal (AE signal) of the EV battery 2 detected by the AE sensor 3 is amplified to a required level in the pre-amplifier unit 6.

[0029] This amplified AE signal is subjected to waveform analysis by waveform analysis unit 7 to eliminate ordinary sound wave signals, and to frequency analysis by frequency analysis unit 8 to eliminate vehicle vibration signals, and from the AE signals extracted and identified by both of these analyses, a discrimination unit 9 discriminates the AE signal corresponding to a crack in the target EV battery 2, and a judgment unit 10 judges this AE signal to be an abnormal signal corresponding to a crack that is a precursor to destruction of the EV battery 2.

[0030] The AE signal determined to be an abnormal signal is output as an abnormal signal detected in response to a crack by the detection signal output unit 11. Although not specifically shown, this output abnormal signal may, for example, be sent to the drive control circuit of the EV as a drive stop signal to stop the EV, or displayed on a monitor as an alarm signal to warn the driver, or may perform both of these actions in combination, thereby preventing damage to the EV battery 2 and ensuring the safety of passengers including the driver.

[0031] The EV battery abnormality detection device 1 configured as above is connected to the EV battery 2 mounted on an EV, and constantly monitors the state of the EV battery 2 while the vehicle is in operation.

[0032] If a tiny crack occurs in the EV battery 2 due to overheating, expansion, shock, etc. while the vehicle is being driven, the AE sensor 3 of the abnormality detection device 1 instantly detects the AE waves emitted from the crack and stops the EV or warns the driver by displaying an alarm signal on the monitor, thereby ensuring the safety of all passengers including the driver.

[0033] As described above in detail, the abnormality detection device 1 for an EV battery 2 of this embodiment is equipped with the AE sensor 3 as a detection unit that detects abnormalities in the EV battery 2, and this AE sensor 3 is installed and fixed to the outer peripheral surface of the main body case of the EV battery 2. Therefore, the occurrence of cracks, which are a precursor to damage to the EV battery 2, can be detected as AE waves, and damage to the EV battery 2 can be detected in advance by signal processing of the AE signal.

[0034] This makes it possible to prevent accidents such as destruction of the EV battery 2 or other problems from occurring, and ensures the safety of the driver.

[0035] It should be noted that the above-described embodiments are merely preferred embodiments of the present invention, and the present invention is not limited to these embodiments, and various design modifications are possible within the scope of the present invention.

[0036] For example, the illustrated embodiment describes the case of detecting an abnormality in EV battery 2, which is a drive battery installed in an EV that uses a large-capacity lithium-ion battery, but the present invention can also be applied to other batteries that supply 12V DC electricity, such as auxiliary batteries installed in EVs and batteries installed in gasoline engine vehicles. [Explanation of symbols]

[0037] 1. EV battery abnormality detection device 2. EV batteries 3 AE sensor 4. Signal Processing Section 5 Main unit case 5a Outer surface of main body case 6 Preamplifier 7 Waveform analysis section 8 Frequency Analysis Section 9. Discrimination Section 10 Judgment section 11 Detection signal output section

Claims

1. An apparatus for detecting an abnormality in an automobile battery, comprising: The battery includes an AE sensor as a detection unit for detecting an abnormality in the battery, The AE sensor is installed and fixed to the outer circumferential surface of the main body case of the battery, The AE signal detected by the AE sensor is processed by a signal processing unit to detect the occurrence of a crack, which is a precursor to destruction of the battery.

2. A vehicle battery abnormality detection device comprising:

2. The signal processing unit includes a preamplifier, a waveform analyzer, a frequency analyzer, a discriminator, a determiner, and a detection signal output unit.

2. The abnormality detection device for an automobile battery according to claim 1.

3. The automobile battery is an EV battery.

3. The abnormality detection device for an automobile battery according to claim 1 or 2.

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