An arrangement for and a method of detecting gas leakage from a battery

Abstract

An arrangement for detecting gas leakage from a battery (6), said arrangement comprising at least one gas detector (1, 2, 3, 4), and a control unit (5). The control unit (5) is configured to receive information regarding the position (P1, P2, P3, P4) of the gas detector (1, 2, 3, 4) with regard to at least one predetermined reference position (Pref.1, Pref.2), and configured to determine a detected gas level for the gas detector (1, 2, 3, 4) at which an alert signal is to be generated on basis of said information regarding the position (P1, P2, P3, P4) of the gas detector (1, 2, 3, 4), and to generate an alert signal when the gas detector (1, 2, 3, 4) detects said gas level determined by the control unit (5).

Description

The present invention relates to an arrangement for detecting gas leakage from a battery, said arrangement comprising at least one gas detector, and a control unit.The present invention also relates to a method of detecting gas leakage from a battery by means of an arrangement according to the present invention.BACKGROUNDIn the realm of electric vehicles (EVs), the widespread adoption of Lithium-Ion (Liion) batteries has significantly advanced automotive technology, offering enhanced efficiency and reduced environmental impact. However, alongside their numerous benefits, Li-ion batteries present unique challenges, particularly concerning safety and maintenance.One critical challenge arises when an EV undergoes servicing or repair in a workshop environment. Li-ion batteries, if damaged or potentially compromised, pose a considerable risk of thermal runaway, a phenomenon characterized by uncontrolled heating and rapid release of stored energy. Such incidents can lead to fires or explosions, endangering personnel and property within the workshop.Existing safety measures often entail complex protocols and specialized equipment, which may not be universally accessible or fool proof in mitigating the risks associated with damaged Li-ion batteries. Moreover, the potential for undetected battery damage during routine maintenance procedures adds an additional layer of concern.Addressing these challenges necessitates innovative solutions capable of ensuring the safe handling and maintenance of EVs equipped with Li-ion batteries within workshop environments. Effective strategies should encompass early detection of battery anomalies, robust containment measures, and efficient emergency response protocols to minimize the risk of thermal runaway incidents and safeguard personnel, infrastructure, and the environment.The present invention seeks to address these pressing concerns by introducing novel technologies and methodologies specifically tailored to enhance workshop safety in the context of EVs powered by Li-ion batteries. Through proactive risk mitigation and comprehensive safety measures, the proposed solution aims to instil confidence in workshop operations while facilitating the continued advancement and adoption of electric mobility.Prior art proposes the use of arrangements comprising a plurality of gas detectors (gas sensors) for detecting gas leakage from batteries on EVs. The gas detectors may, typically be configured to detect and measure the content of gases such as carbon monoxide, carbon dioxide, hydrogen fluoride or hydrocarbons in order to detect gas leakage from batteries. On ore more detectors may be positioned in the region of the EV for the purpose of detecting gas leakage. Normally, the battery, and the chassis of the EV, has a safety valve opening through which gas inside the battery may be evacuated from the battery. There may also be one or more holes in the battery housing, for example caused by damage thereon. Detectors may be positioned in the region of such openings or holes in order to enable quick and reliable detection of gas leakage. However, gas may leak from other, non-localised, positions on the battery housing, and therefore there might be of interest to arrange further gas detectors in order to detect leakages emanating also from such other positions on the battery housing, or even emanating from a completely different source. Depending on where the detectors are positioned, they are more or less likely to be subjected to a locally high gas content caused by leakage from the battery or elsewhere. It is an object of the invention to present an arrangement that takes into consideration the fact that leakage may occur from different locations, not only the obvious ones, and that enables detection of any leakage that could be of hazardous or detrimental character for an EV itself as well as for the surrounding environment and people working in that environment.The object of the invention is achieved by means of an arrangement for detecting gas leakage from a battery, said arrangement comprising- at least one gas detector, and- a control unit,the arrangement being characterized in that the control unit is configured to receive information regarding the position of the gas detector with regard to at least one predetermined reference position, and configured to determine a detected gas level for the gas detector at which an alert signal is to be generated on basis of said information regarding the position of the gas detector, and to generate an alert signal when the gas detector detects said gas level determined by the control unit.The control unit is thus configured to take into consideration the position of each detector with regard to the predetermined reference position or positions. Typically selected a reference position is a position in which leakage from the battery is more likely to occur, such as an outlet connected to a safety valve of the battery or a hole in the battery housing. The control unit is thus preferably configured to determine a lower alert level (content of detected gas) for a gas detector the more distanced the gas detector is from a specific reference position, provided the reference position is the position of a hole in the battery housing (and chassis of an EV) or a battery safety valve outlet in the battery housing. The control unit preferably comprises an electronic control circuitry.According to some embodiments, said at least one reference position comprises a position of a safety valve outlet of a battery housing or an opening of a battery housing.According to some embodiments, the control unit is configured to determine a rate of change of the gas level detected by the gas detector and to generate an alert signal when the change of rate is above a predetermined level. Accordingly, an alert signal may be generated on basis of the rate of change of the gas level before the critical gas level, at which an alert signal is to be generated, has even been obtained. In particular, if relatively high changes of rate are detected by one or more sensors that are remote from reference positions such as holes in the battery housing and safety valve outlets, the change of rate may be a more critical indicator of leakage than the rate (absolute value of the gas content) itself. The control unit is thus preferably configured to determine a lower alert level on basis of the measured rate of change of the detected gas content for a gas detector the more distanced the gas detector is from a specific reference position, provided the reference position is the position of a hole in the battery housing (and chassis of an EV) or a battery safety valve outlet in the battery housing.According to some embodiments, the control unit itself is thus configured to determine said rate of change of the gas level detected by the gas detector, at which an alert signal is to be generated, on basis of the of said information regarding the position of the gas detector or gas detectors.According to some embodiments, the arrangement comprises a plurality of gas detectors, wherein the control unit is configured to receive information of a position of each gas detector with regard to said reference position.According to some embodiments, the control unit is configured to determine, on basis of the input from the gas detectors, if gas detected by one or more of the gas detectors emanates from the region of the at least one reference position.According to some embodiments, the at least one gas detector is configured to measure the content in atmospheric air of one or more of hydrocarbons, hydrogen gas, hydrogen fluoride, carbon monoxide and carbon dioxide.According to some embodiments, the at least one gas detector is configured to measure the content of hydrogen fluoride.According to some embodiments, the at least one gas detector is configured to measure the content of carbon monoxideAccording to some embodiments, the at least one gas detector is configured to measure the content of carbon dioxide.According to some embodiments, the at least one gas detector is configured to measure the content of hydrogen gas.The object of the invention is also achieved by means of a method of detecting gas leakage from a battery by means of an arrangement as defined hereinabove or hereinafter, said method comprising the steps of,- defining at least one reference position,- positioning a first gas detector in a first position,- providing the control unit of the arrangement with information regarding the at least one reference position and the first position,- measuring a gas level by means of the first gas detector, and- generate an alert signal if an alert level determined by the control unit for the first gas detector is detected.According to some embodiments, the method comprises the further steps of - positioning a second gas detector in a second position,- providing the control unit of the arrangement with information regarding the second position.- measuring a gas level by means of the second gas detector, and- generating an alert signal if an alert level determined by the control unit for the second gas detector is detected.The alert level determined by the control unit for each gas detector comprises a predetermined gas content level at which an alert signal is to be generated. According to some embodiments, the alert level also comprises a change of rate (change of gas content per time unit) determined by the control unit for each gas detector with regard taken to the position of the gas detector and at least one reference position. An alerts signal will be generated depending on which alert level (the one regarding content alone or the one regarding change of rate) is obtained first for a predetermined gas detector.According to some embodiments, the first position is a position adjacent to the reference position and the second position is a position more remote from the reference position than the first position. The method preferably comprises positioning a gas detector at each hole or safety valve outlet of the battery housing, and to position at least one further gas detector more remotely from the at least one reference position (i.e. said outlet or opening).The present invention also relates to a data program (P), programmed for causing the arrangement according to the present invention to execute the steps performed by the control unit in the method according to the present invention, wherein said data program (P) comprises a program code readable on a computer of the control unit for providing said method.Further features of the present invention will be presented in the following detailed description of embodiments.BRIEF DESCRIPTION OF THE DRAWINGSAn embodiment of the present invention will be described more in detail with regard to the annexed drawing, on which;Fig. 1 is a schematic representation of an arrangement according to the present invention, arranged for measuring gas leakage of a battery, andFig. 2 is a flow chart showing an example of a method according to the present invention.DETAILED DESCRIPTIONFig. 1 shows an example of an arrangement according to the present invention. The arrangement comprises a plurality of gas detectors 1-4, and a control unit 5.The control unit 5 is configured to receive information regarding the position (P1, P2, P3, P4) of the respective gas detectors 1-4 with regard to a first reference position Pref.1 and a second reference position Pref.2. Here, it is the distance to the respective gas detector 1-4 from each reference position that is received by the control unit 5. Each gas detector 1-4 may comprise its own position-determining device through which the position data may be transmitted to the control unit 5.The first reference position Pref. 1 is defined by a position of a safety valve outlet of a housing of a battery 6. The second reference position Pref.2 is defined by an opening of the housing of the battery 6, typically caused by a damage on the housing. The battery is a Li-ion battery. According to some embodiments, the battery 6 is arranged in connection to the chassis of an electric vehicle, typically a car, wherein the battery 6 is used for the traction of the vehicle.Each gas detector 1 -4 is configured to measure the content of a predetermined gas in atmospheric air. On basis of the information regarding the position P1-P4 of each gas detector 1-4 with regard to the reference positions Pref.1 and Pref.2, the control unit 5 is configured to determine a detected gas level for each gas detector 1-4 at which an alert signal is to be generated, and to generate an alert signal when the gas detector 1-4 detects said gas level determined by the control unit 5.The control unit 5 is configured to determine a rate of change of the gas level detected by the respective gas detector 1-4 and to generate an alert signal when the change of rate is above a predetermined level. On basis of the information regarding the position P1-P4 of each gas detector 1-4 with regard to the reference positions Pref.1 and Pref.2, the control unit 5 is configured to determine a predetermined change of rate for each gas detector 1-4, at which change of rate an alert signal is to be generated, and to initiate such alert signal generation if the predetermined change of a gas detector 1-4 is registered.Accordingly, an alert signal may be generated on basis of the rate of change of the gas level before the critical gas level, at which an alert signal is to be generated, has even been obtained. In particular, if relatively high changes of rate are detected by one or more gas detectors 3, 4 that are remote from the reference positions Pref.1 and Pref.2, the change of rate may be a more critical indicator of leakage the rate (absolute value of the gas content) itself. The control unit 5 is thus preferably configured to determine a lower alert level on basis of the measured rate of change of the detected gas content for a gas detector the more distanced the gas detector is from a specific reference position, provided the reference position is the position of a hole in the battery housing (and chassis of an EV) or a battery safety valve outlet in the battery housing.The control unit 5 is configured to determine, on basis of the input from the gas detectors 1-4, if gas detected by one or more of the gas detectors 1-4 emanates from the region of the reference positions, i.e. from an opening in the battery housing or from an outlet from a safety valve. If a gas detector 3, 4 remote from the reference detects a gas content or a change of rate such that it will trigger an alert signal before any of the gas detectors 1, 2 adjacent to the reference positions Pref.1 and Pref.2 detects a gas content or a change of rate that will trigger an alert signal, the control unit 5 is configured to determine that a gas leakage is from another position than any of the reference position, and to present that as output.The at least one gas detector is configured to measure the content in atmospheric air of hydrocarbons, hydrogen gas, hydrogen fluoride, carbon monoxide and carbon dioxide.With reference to fig. 2, a method of detecting gas leakage from a battery 6 by means of an arrangement as defined hereinabove is presented. The method comprises the of,S1 : defining the first and second reference position Pref.1 and Pref.2,S2: positioning a respective gas detector 1, 2 adjacent the first and second reference positions Pref.1 and Pref.2,S3: positioning further gas detectors 3, 4 remote from the reference positions Pref.1 and Pref.2,S4: providing the control unit 5 of the arrangement with information regarding the reference positions and the positions of the respective gas detector 1 -4,S5: determining by means of the control unit 5, for each gas detector 1-4, with regard to its distance to the respective reference positions Pref.1 and Pref.2, a gas level and a change of rate of gas level for which an alert signal is to be generated, S6: measuring a gas level in atmospheric air and the change of rate of the gas level by means of each gas detector and the control unit 5, andS7: generating an alert signal if an alert level determined by the control unit 5 for any gas detector 1-4 is detected.The present invention also relates to a data program (P), programmed for causing the arrangement according to the present invention to execute the method according to the present invention, wherein said data program (P) comprises a program code readable on a computer of the control unit for providing said method.

Claims

1. An arrangement for detecting gas leakage from a battery (6), said arrangement comprising- at least one gas detector (1, 2, 3, 4), and- a control unit (5),the arrangement being characterized in that the control unit (5) is configured to receive information regarding the position (P1, P2, P3, P4) of the gas detector (1, 2, 3, 4) with regard to at least one predetermined reference position (Pref.1, Pref.2), and configured to determine a detected gas level for the gas detector (1, 2, 3, 4) at which an alert signal is to be generated on basis of said information regarding the position (P1, P2, P3, P4) of the gas detector, and to generate an alert signal when the gas detector (1, 2, 3, 4) detects said gas level determined by the control unit (5).

2. An arrangement according to claim 1, wherein said reference position (Pref.1, Pref.2) is a position of a safety valve outlet of a battery housing or an opening of a battery housing.

3. An arrangement according to claim 1 or 2, wherein the control unit (5) is configured determine a rate of change of the gas level detected by the gas detector (1, 2, 3, 4) and to generate an alert signal when the change of rate is above a predetermined level.

4. An arrangement according to claim 3, wherein the control unit (5) is configured to determine said rate of change of the gas level detected by the gas detector, at which an alert signal is to be generated, on basis of the of said information regarding the position (P1, P2, P3, P4) of the gas detector.

5. An arrangement according to any one of claims 1 -4, wherein the arrangement comprises a plurality of gas detectors, and wherein the control unit (5) is configured to receive information of a position (P1, P2, P3, P4) of each gas detector (1, 2, 3, 4) with regard to said at least one reference position (Pref.1, Pref.2).

6. An arrangement according to claim 5, wherein the control unit (5) is configured to determine, on basis of the input from the gas detectors, if gas detected by one or more of the gas detectors emanates from the region of the at least one reference position (Pref.1, Pref.2).

7. An arrangement according to any one of claims 1 -6, wherein the at least one gas detector (1, 2, 3, 4) is configured to measure the content in atmospheric air of one or more of hydrocarbons, hydrogen gas, hydrogen fluoride, carbon monoxide and carbon dioxide.

8. An arrangement according to any one of claims 1 -7, wherein the at least one gas detector (1, 2, 3, 4) is configured to measure the content of hydrogen fluoride.

9. An arrangement according to any one of claims 1 -8, wherein the at least one gas detector (1, 2, 3, 4) is configured to measure the content of carbon monoxide10. An arrangement according to any one of claims 1 -9, wherein the at least one gas detector (1, 2, 3, 4) is configured to measure the content of carbon dioxide11. An arrangement according to any one of claims 1-10, wherein the at least one gas detector (1, 2, 3, 4) is configured to measure the content of hydrogen gas.

12. A method of detecting gas leakage from a battery by means of an arrangement according to any one of claims 1-11, said method comprising the steps of,- defining at least one reference position (Pref.1, Pref.2),- positioning a first gas detector (1, 2, 3, 4) in a first position (P1, P2, P3, P4), - providing the control unit (5) of the arrangement with information regarding the at least one reference position (Pref.1, Pref.2) and the first position (P1, P2, P3, P4), - measuring a gas level by means of the first gas detector, and- generate an alert signal if an alert level determined by the control unit (5) for the first gas detector (1, 2, 3, 4) is detected.

13. A method according to claim 11, comprising the further step of - positioning a second gas detector (1, 2, 3, 4) in a second position (P1, P2, P3, P4), - providing the control unit (5) of the arrangement with information regarding the second position (P1, P2, P3, P4).- measuring a gas level by means of the second gas detector, and- generate an alert signal if an alert level determined by the control unit (5) for the second gas detector (1, 2, 3, 4) is detected.

14. A method according to claim 13, wherein the first position (P1, P2) is a position adjacent the at least one reference position (Pref.1, Pref.2) and the second position (P3, P4) is a position more remote from the at least one reference position (Pref.1, Pref.2) than the first position (P1, P2).

15. A data program (P), programmed for causing the arrangement according to any of claims 1-11 to execute the steps performed by the control unit (5) in the method according to any of claims 12-14, wherein said data program (P) comprises a program code readable on a computer of the control unit (5) for providing said method.