EP4740258A1

EP4740258A1 - Method and device for storing batteries

Info

Publication number: EP4740258A1
Application number: EP23755006.6A
Authority: EP
Inventors: Heng Zhu; Zhongling WEI; Xiangxiang SHAO; Tao Zhang; Baofeng WEN; Linhan GE
Original assignee: North Star Advanced Recycling Technology Tsingtao Co Ltd; Linde GmbH
Current assignee: North Star Advanced Recycling Technology Tsingtao Co Ltd; Linde GmbH
Priority date: 2023-07-06
Filing date: 2023-07-06
Publication date: 2026-05-13
Also published as: WO2025007339A1

Abstract

The present invention relates to a method of storing batteries comprising the following steps: placing the batteries onto a storage tray (110), monitoring a surface temperature of the batteries by using a thermal imaging camera (130), detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature, and, if the surface temperature of one of the batteries exceeds the predetermined threshold temperature, providing a cryogenic liquid flow as a coolant through a cryogenic liquid injector (120) onto at least the respective one of the batteries, the surface temperature of which exceeding said predetermined threshold temperature, and it relates to a corresponding storage device (100).

Description

Method and device for storing batteries

The present invention relates to a method of storing batteries, particularly spent batteries, more particularly spent Lithium Ion Batteries (LIB) , and to a corresponding storage device.

Technical Field

The storage of spent batteries, particularly spent Lithium Ion Batteries (LIB) , runs the risk of having a thermal runaway due to internal short circuits. Such a thermal runaway most likely results in a development of fire. The current technology is limited to use conventional fire extinguishing agents, such as dry powder, foam, carbon dioxide, or water, to put out the fire.
CN 215474806 U discloses a safe transportation and storage device for lithium batteries including a liquid nitrogen tank, an electric control valve, a transportation bin, a storage bin, and one or more temperature measurement resistance sensors, a smoke alarm sensor as well as a sound and light alarm. When the temperature resistance sensor detects a high temperature in the storage bin or the smoke alarm sensor detects a high concentration of smoke in the transport bin, the electric control valve is opened such that liquid nitrogen from the liquid nitrogen tank enters the storage bin such that the burning accident is eliminated. In this way, when a lithium battery burns, liquid nitrogen is released from the tank to cool down the storage bin and to extinguish the fire.
Although the prior art provides a technology for extinguishing fire in Lithium Ion Batteries storage bins, such technologies are not able to avoid the development of fire in such storage bins.
Summary of the present invention
The present invention provides a method of storing batteries and a corresponding storage device according to the independent claims. Embodiments of the invention are the subject matter of the respective dependent claims and of the description as follows.
The method of storing batteries according the present invention comprises the steps of placing the batteries onto a storage tray, monitoring a surface temperature of the batteries by using a thermal imaging camera, detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature, and, if the surface temperature of one of the batteries exceeds the predetermined threshold temperature, providing a cryogenic liquid flow as a coolant through a cryogenic liquid injector onto at least the respective one of the batteries, the surface temperature of which exceeds said predetermined threshold temperature. It is noted that the step of monitoring a surface temperature of the batteries does not necessarily include the step of determining an actual surface temperature as it is sufficient to determine values being in relation to the surface temperature of the batteries, such values being delivered by e.g. an image of a thermal imaging camera. Same applies to the step of detecting if a predetermined threshold temperature is exceeded, which predetermined threshold temperature does not necessarily need to be an actual temperature but rather a value corresponding to such a temperature. The temperature distribution in an image taken by a thermal imaging camera allows a person skilled in the art to set such a threshold temperature (corresponding to a pixel value in the image) . If this predetermined threshold value/temperature is exceeded, an internal short circuit in a battery or another incident is likely to have happened resulting in a possible thermal runaway or fire. In that case, a cryogenic liquid flow is directed onto at least the respective battery. Thus, the invention allows to detect a thermal runaway in an early stage and to mitigate or to prevent such a thermal runaway or even fire with a cryogenic liquid flow. Thus, the occurrence of fire is effectively prevented.
It is noted that the term “acryogenic liquid flow” comprises the output of a cryogenic liquid through the injector. Thus, in an embodiment, a flow of cryogenic liquid, particularly of an inert cryogenic liquid, more particularly of liquified nitrogen (LIN) can be used as the cryogenic liquid flow. The boiling temperature of liquified nitrogen is about -320°F (= -196℃) such that the injected cryogenic liquid flow can be used as an effective inert coolant. Same is true for other cryogenic liquids like liquid argon, helium, carbon dioxide or even hydrogen or oxygen. Since hydrogen and oxygen are not inert, a possible inflammability has to be taken into account.
An advantage of using a cryogenic liquid like LIN as a coolant is that LIN could take away the heat produced due to the internal short circuit much faster than conventional fire extinguishing agents, e.g. water. This helps prevent heat cumulation inside a battery, so as to prevent developing into the thermal runaway. Meanwhile, a cryogenic liquid like LIN can freeze electrolyte inside a battery to stop the reaction between electrolyte and anode active material which could be triggered by the decomposition of the SEI (= “solid electrolyte interphase” ) film due to the temperature increase inside a battery.
In an embodiment, the method comprises the step of detecting the location of the respective battery, the surface temperature of which exceeding said predetermined threshold temperature. Detecting the location of the respective battery is particularly useful for identifying the problematic battery in order to direct the cryogenic liquid flow onto the detected location of the battery and/or relocate the respective battery. In some embodiments, the cryogenic liquid injector is configured to be directed onto the detected location of the respective battery. Relocating the respective battery may include automatically (or manually) gripping and removing the battery from the storage tray.
In an embodiment, an infrared (IR) -camera is used as the thermal imaging camera. Such cameras are well known in the prior art and provide a thermal image showing a temperature distribution of the batteries located on the storage tray. Since the pixel values correspond to a temperature at the corresponding location, it is possible to monitor the surface temperatures and to detect temperatures above a predetermined threshold temperature. The threshold temperature can be about 50℃ or more generally in a range of 40℃ and 100℃, particularly between 50℃ and 90℃, more particularly between 50℃ and 80℃. The preferred temperature threshold is 50℃.
It should be noted that according to the present invention it is not necessary to detect the location of the problematic battery but it is possible to provide the cryogenic liquid flow all over the storage tray where the batteries are located. The important thing is to provide the cryogenic liquid flow onto an area including the problematic battery.
In an embodiment, the batteries are placed onto the storage tray such that only a single layer of batteries is formed, i.e. a piling up of batteries on the storage tray is avoided. This ensures a better detectability of a problematic battery.
In an embodiment, a weight of the batteries placed on the storage tray is measured and depending on the measured weight an amount of cryogenic liquid flow is determined, which amount is then sprayed or otherwise provided onto at least the respective one of the batteries or the respective (part of the) storage tray. In case of a constant flow rate through the injector, the amount of cryogenic liquid to be provided can be specified by the corresponding time of providing the cryogenic liquid.
The invention is particularly useful for storing spent batteries, in particular lithium ion batteries (LIB) .
The present invention also relates to a storage device for storing batteries. The storage device comprises a storage tray for placing batteries thereon, a thermal imaging camera for monitoring a surface temperature of the batteries placed onto the storage tray, a detector, the detector being configured for detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature, a cryogenic liquid injector for injecting a cryogenic liquid flow, the cryogenic liquid injector being configured to provide the cryogenic liquid flow onto at least a part of the storage tray, and a controller, the controller being operatively connected to the detector and to the cryogenic liquid injector and being configured to control the cryogenic liquid injector to provide the cryogenic liquid flow as a coolant onto at least a respective battery, the surface temperature of which exceeding said predetermined threshold temperature as detetected by the detector.
Embodiments and advantages of the storage device according the present invention correspond to those of the method of storing batteries according to the present invention as discussed above. Thus, reference is made to the above discussion.
It is noted that the detector for detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature may be a standalone device but may also be at least in part a part of the thermal imaging camera and/or of the controller of the storage device. Thus, the detector might be included in the thermal imaging camera and be configured to scan the pixel values of the image taken by the thermal imaging camera in order to identify pixel values corresponding to temperature values exceeding the predetermined threshold temperature. It is also possible that at least a part of this temperature detection is performed by the controller. As a result, an abnormal temperature raise is detected such that the controller triggers the cryogenic liquid injector to spray or otherwise provide cryogenic liquid onto the batteries placed on the tray.
As already discussed above, the detector may be configured for detecting the location of the respective problematic battery. In that case, the cryogenic liquid injector may be configured for being directed onto the detected location of the respective battery. Also, the storage device may be configured for relocating the respective battery, e.g. by a robot gripper for gripping and removing the respective battery from the storage tray.
In an embodiment, the storage device also comprises a storage tray weight determination device configured to determine or measure a weight of the batteries placed on the storage tray (including or not including the weight of the storage tray itself) such that, by e.g. the controller, an amount of the cryogenic liquid flow depending on the measured weight can be determined, which amount is then sprayed or otherwise provided onto at least the respective one of the batteries or the respective (part of the) storage tray. In case of a constant flow rate through the injector, the amount of cryogenic liquid to be provided can be specified by the corresponding time of providing the cryogenic liquid. This embodiment ensures that also a heavily loaded storage tray is efficiently cooled down by providing higher amounts of cryogenic liquid.
In an embodiment, the storage device also comprises a reservoir of liquid cryogenic gas, the cryogenic liquid injector being connected to the reservoir of liquid cryogenic gas, particularly inert cryogenic gas, more particularly liquified nitrogen. In this case, the cryogenic liquid injector may be connected to the liquified cryogenic gas reservoir by a pipe including an electric control valve, which valve is controlled by the controller. As soon as an abnormal temperature is detected, i.e. the battery temperature exceeds the predetermined threshold temperature, the controller opens the electric control valve such that crogenic liquid is ejected out of the nozzle of the injector and sprayed or otherwise provided onto the storage tray. As a result, the temperature of the batteries will decrease rapidly and the internal reaction inside the problematic battery will be mitigated.
In an embodiment, the strorage device comprises a liquid gas separator and/or a subcooler installed in a pipe connecting the reservoir of liquified cryogenic gas and the cryogenic liquid injector in order to be able to decrease the response time of providing cryogenic liquid, i.e. in order to be able to instantaneously spray or otherwise provide cryogenic liquid onto the batteries.
In an embodiment, the storage device comprises a plurality of equally equipped layers in order to increase the storage capacity. Thus, the storage device may comprise a plurality of storage trays, each storage tray being equipped with an associated thermal imaging camera for monitoring a surface temperature of the batteries placed onto the associated storage tray, further with an associated detector, the detector being configured for detecting if the surface temperature of one of the batteries placed onto the associated storage tray exceeds a predetermined threshold temperature, and with an associated cryogenic liquid injector for injecting a cryogenic liquid flow, the cryogenic liquid injector being configured to provide the cryogenic liquid flow onto at least a part of the associated storage tray.
Brief description of the figures
Figure 1 schematically shows a storage device according to an embodiment of the present invention, the storage device being configured for implementing an embodiment of the method of storing batteries according to the present invention.

Detailed description

Figure 1 schematically shows a storage device 100 for storing batteries including a housing 150. Within the housing 150 a storage tray 110 is arranged for placing batteries thereon, the batteries are not shown for a better overview. Particularly spent batteries, in particular spent LIBs are placed onto the storage tray 110 such that a single layer of batteries is formed in order to avoid a piling up.
The storage device 100 further comprises a thermal imaging camera 130 for monitoring a surface temperature of the batteries placed onto the storage tray 110. In this embodiment, the thermal imaging camera 130 is an IR-camera arranged at the top of the housing 150 such that the field of view of the camera 130 covers the area of the storage tray 110.
The storage device 100 further comprises a cryogenic liquid injector 120 for injecting a cryogenic liquid flow, the cryogenic liquid injector 120 being configured to provide a cryogenic gas flow onto at least a part of the storage tray 110. In this embodiment, the cryogenic liquid injector 120 comprises a pipe as shown in Figure 1 having one or more injection nozzles for ejecting liquified cryogenic gas.
The storage device 100 further comprises a controller 140. The controller 140 may also be arranged within the housing 150 or at an inner or outer side of a wall of the housing 150 inside or outside the housing 150. In the present embodiment, the detector for detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature is part of the thermal imaging camera 130. The controller 140 is operatively connected to the detector i.e. to the camera 130 and to the cryogenic liquid injector 120 and is configured to control the cryogenic liquid injector 120 to provide the cryogenic liquid flow as a coolant onto at least the respective battery, the surface temperature of which exceeding said predetermined threshold temperature as detected by the detector.
In this embodiment shown in Figure 1, as soon as the detector inside the thermal imaging camera 130 detects an abnormal surface temperature of one of the batteries located on the storage tray 110 by processing the thermal images taken by the thermal imaging camera 130, a corresponding signal is sent to controller 140, which controller 140 controls the cryogenic liquid injector 120 to inject a cryogenic liquid flow onto at least a part of the storage tray 110. In this embodiment, the area of the storage tray 110 is covered by the cryogenic liquid flow ejected from injector 120. As already described above, the cryogenic liquid injector may comprise an electric control valve, which is opened by the controller 140 such that a cryogenic liquid can enter the pipe of the cryogenic liquid injector 120 such that the cryogenic liquid ejects from injector nozzles of the cryogenic liquid injector 120. In case of liquified nitrogen, liquid nitrogen is ejected from the nozzles. The temperature of the batteries including the problematic battery will decrease sharply such that any further thermal runaway is stopped. Any possible fire development is therefore prevented from the beginning. An operator or an automatic gripper can then relocate the batteries or –if the location of the problematic battery has been detected –the problematic battery itself and take it to safer place to avoid impacting the surrounding batteries.

Claims

A method of storing batteries comprising the following steps:

placing the batteries onto a storage tray (110) ,

monitoring a surface temperature of the batteries by using a thermal imaging camera (130) ,

detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature,

and, if the surface temperature of one of the batteries exceeds the predetermined threshold temperature, providing a cryogenic liquid flow as a coolant through a cryogenic liquid injector (120) onto at least the respective one of the batteries, the surface temperature of which exceeding said predetermined threshold temperature.
The method of claim 1, comprising the step of detecting the location of the respective battery, the surface temperature of which exceeding said predetermined threshold temperature.
The method of claim 2, further comprising the steps of directing the cryogenic liquid injector (120) and/or the cryogenic liquid flow onto the detected location of the respective battery and/or relocating the respective battery.
The method of claim 3, comprising the step of relocating the respective battery, wherein the respective battery is relocated by removing the battery from the storage tray (110) .
The method of anyone of the preceding claims, wherein an amount of the cryogenic liquid flow is based on a weight of the batteries on the storage tray (110) .
The method of anyone of the preceding claims, wherein an IR-camera is used as the thermal imaging camera.
The method of anyone of the preceding claims, wherein a flow of inert cryogenic liquid, particularly of liquified nitrogen, is used as the cryogenic liquid flow.
The method of anyone of the preceding claims, wherein spent batteries, in particular Lithium Ion Batteries, are used as the batteries.
The method of anyone of the preceding claims, wherein the batteries are placed onto the storage tray (110) such that only a single layer of batteries is formed.
A storage device (100) for storing batteries comprising

a storage tray (110) for placing batteries thereon;

a thermal imaging camera (130) for monitoring a surface temperature of the batteries placed onto the storage tray (110) ;

a detector, the detector being configured for detecting if the surface temperature of one of the batteries exceeds a predetermined threshold temperature;

a cryogenic liquid injector (120) for injecting a cryogenic liquid flow, the cryogenic liquid injector (120) being configured to provide the cryogenic liquid flow onto at least a part of the storage tray (110) ; and

a controller (140) , the controller being operatively connected to the detector and to the cryogenic liquid injector (120) and being configured to control the cryogenic liquid injector (120) to provide the cryogenic liquid flow as a coolant onto at least a respective battery, the surface temperature of which exceeding said predetermined threshold temperature as detected by the detector.
The storage device (100) of claim 10, wherein the detector is configured for detecting the location of the respective battery, and particularly wherein the cryogenic liquid injector (120) is configured for being directed onto the detected location of the respective battery and/or the storage device (100) is configured for relocating the respective battery.
The storage device of any one of the claims 10 or 11, wherein the thermal imaging camera (130) is an IR-camera.
The storage device (100) according to any one of the claims 10-12, wherein the cryogenic liquid injector (120) is connected to a reservoir of liquified cryogenic gas, particularly liquified inert cryogenic gas, more particularly liquified nitrogen.
The storage device (100) according to claim 13, wherein a liquid gas separator and/or a subcooler is installed in a pipe connecting the reservoir of liquified cryogenic gas and the cryogenic liquid injector (120) .
The storage device (100) of any one of the claims 10-14, wherein the storage device (100) comprises a plurality of storage trays (110) , each storage tray (110) being equipped with an associated thermal imaging camera (130) for monitoring a surface temperature of the batteries placed onto the associated storage tray (110) , further with an associated detector, the detector being configured for detecting if the surface temperature of one of the batteries placed onto the associated storage tray (110) exceeds a predetermined threshold temperature, and with an associated cryogenic liquid injector (120) for injecting a cryogenic liquid flow, the cryogenic liquid injector (120) being configured to provide the cryogenic liquid flow onto at least a part of the associated storage tray (110) .