A method, system and device for calculating the ventilation area of ​​a container for transporting lithium batteries

Abstract

The present invention relates to a method, system and device for calculating the ventilation area of ​​a container for transporting lithium batteries. The present invention considers the calculation of ventilation area from two aspects. On the one hand, thermal runaway of lithium batteries produces a large amount of gas, which leads to an increase in gas in the container. On the other hand, thermal runaway of lithium batteries causes the temperature in the container to rise, and then the temperature rise causes the gas in the container to expand and the pressure in the box to increase. Based on the above two aspects, the ventilation area of ​​the lithium battery transport container is calculated. Through the present invention, the ventilation area of ​​the container can be calculated more accurately, while ensuring that the lithium battery can be exhausted smoothly when thermal runaway occurs, the influence of the ventilation opening on the function of the container itself is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery transportation, and in particular to a method, system and device for calculating the ventilation opening area of ​​a container for transporting lithium batteries. Background Art

[0002] Thermal runaway is a condition in which a large amount of heat is accumulated inside a lithium-ion battery due to various factors, while the heat dissipation rate is slow. This causes a large amount of heat to accumulate inside the battery, triggering a series of side reactions. During the transportation of lithium batteries, containers are generally used to load and transport packaged lithium batteries. Lithium batteries are subject to external factors such as squeezing and high temperature in containers, which can easily lead to thermal runaway and release a large amount of carbon monoxide gas.

[0003] Therefore, it is necessary to open vents on the container. The vents of the container mainly play the role of ventilation and pressure equalization. If the vents are too small, it is difficult to ensure that the gas in the container can be discharged smoothly when thermal runaway occurs, increasing the safety risk; if the vents are too large, it will affect the flame retardant, heat insulation and thermal insulation functions of the container itself. In the relevant technology, there is a lack of a method for calculating the vent area of ​​a container specifically used for loading lithium batteries. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method, system and device for calculating the ventilation opening area of ​​a container for transporting lithium batteries, so as to solve the above technical problem.

[0005] The technical solution of the present invention to solve the above technical problems is as follows: a method for calculating the ventilation area of ​​a container for transporting lithium batteries, comprising: obtaining the lithium battery exhaust rate, the remaining volume of the container, the initial temperature of the container and the temperature change rate of the container for transporting lithium batteries; wherein the lithium battery exhaust rate is the rate at which all battery cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; the initial temperature of the container is the temperature inside the container after the lithium battery is loaded; the temperature change rate is the rate at which the temperature inside the container rises after all battery cells in any packaging unit loaded in the container are completely thermal runaway; according to the lithium battery exhaust rate and the remaining volume of the container, a first exhaust wind speed is calculated; the first exhaust wind speed represents the wind speed required to discharge the gas released by all battery cells in any packaging unit loaded in the container due to complete thermal runaway from the container; according to the lithium battery exhaust rate and the first exhaust wind speed, a first ventilation area is calculated; The first ventilation area represents the ventilation area required to discharge the gas released by all the battery cells in any packaging unit loaded in the container due to complete thermal runaway from the container; the gas expansion rate is calculated according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; the gas expansion rate is the rate at which the gas in the container expands after all the battery cells in any packaging unit loaded in the container have completely thermal runaway, causing the temperature in the container to rise; the second exhaust wind speed is calculated according to the gas expansion rate and the remaining volume of the container; the second exhaust wind speed represents the wind speed required to balance the increased pressure inside the container caused by the expansion of the gas in the container; the second ventilation area is calculated according to the gas expansion rate and the second exhaust wind speed; the second ventilation area represents the ventilation area required to balance the increased pressure inside the container caused by the expansion of the gas in the container; the ventilation area of ​​the container is obtained according to the first ventilation area and the second ventilation area.

[0006] The beneficial effect of the present invention is that the present invention considers the calculation of ventilation area from two aspects respectively. On the one hand, the thermal runaway of lithium batteries produces a large amount of gas, which leads to an increase in gas in the container. On the other hand, the thermal runaway of lithium batteries causes the temperature in the container to rise, and then the temperature rise causes the gas in the container to expand and the pressure in the box to increase. Based on the above two aspects, the ventilation area of ​​the lithium battery transport container is calculated. Through the present invention, the ventilation area of ​​the container can be calculated more accurately, which can ensure that the internal and external pressures of the container can be smoothly balanced when the lithium battery is thermally runaway, while reducing the influence of the ventilation opening on the function of the container itself.

[0007] Based on the above technical solution, the present invention can also be improved as follows.

[0008] Furthermore, the lithium battery exhaust rate is obtained in the following manner: obtaining the number of battery cells contained in any packaging unit that has completely experienced thermal runaway, the battery cell capacity, the amount of battery cell gas released, and the lithium battery exhaust time; calculating the lithium battery gas release volume based on the number of battery cells contained in the packaging unit, the battery cell capacity, and the battery cell gas release volume; calculating the lithium battery exhaust rate based on the lithium battery gas release volume and the lithium battery exhaust time.

[0009] Furthermore, the cell gas release amount is the cell gas release amount corresponding to when a cell with a state of charge of 40% completely experiences thermal runaway.

[0010] Further, the calculating a first exhaust wind speed according to the lithium battery exhaust rate and the remaining volume of the container includes: calculating a first pressure change rate by a first formula according to the lithium battery exhaust rate and the remaining volume of the container, wherein the first pressure change rate is a rate at which the pressure in the container changes due to the gas released by all the cells in any packaging unit loaded in the container due to complete thermal runaway;

[0011] The first formula is: ;

[0012] in, refers to the first pressure change rate, Refers to atmospheric pressure, Refers to the exhaust rate of lithium batteries, Refers to the remaining volume of the container;

[0013] Calculating the first exhaust wind speed by a second formula according to the first pressure change rate;

[0014] The second formula is: ;

[0015] in, Refers to the first row wind speed, Refers to the carbon monoxide density of the air.

[0016] Further, calculating the first ventilation area according to the lithium battery exhaust rate and the first exhaust wind speed includes: calculating a first ratio of the lithium battery exhaust rate to the first exhaust wind speed, and determining the first ratio as the first ventilation area.

[0017] Further, the calculating the gas expansion rate according to the remaining volume of the container, the initial temperature of the container and the temperature change rate includes: calculating the gas expansion rate by a third formula according to the remaining volume of the container, the initial temperature of the container and the temperature change rate;

[0018] The third formula is: ;

[0019] in, The gas expansion rate, Refers to the remaining volume of the container. The rate of temperature change, Refers to the initial temperature of the container.

[0020] Further, the calculating the second exhaust wind speed according to the gas expansion rate and the remaining volume of the container includes: calculating a second pressure change rate according to the gas expansion rate and the remaining volume of the container by a fourth formula, wherein the second pressure change rate is a rate of change of the pressure inside the container caused by the expansion of the gas in the container;

[0021] The fourth formula is: ;

[0022] in, refers to the second pressure change rate, Refers to atmospheric pressure, The gas expansion rate, Refers to the remaining volume of the container;

[0023] Calculating the second exhaust wind speed by a fifth formula according to the second pressure change rate;

[0024] The fifth formula is: ;

[0025] in, Refers to the second row wind speed, Refers to the carbon monoxide density of the air.

[0026] Further, calculating the second ventilation area according to the gas expansion rate and the second exhaust wind speed includes: calculating a second ratio of the gas expansion rate to the second exhaust wind speed, and determining the second ratio as the second ventilation area.

[0027] In order to solve the above technical problems, the present invention also provides a ventilation opening area calculation system for a container for transporting lithium batteries, comprising:

[0028] An acquisition module is used to acquire the lithium battery exhaust rate, the remaining volume of the container, the initial temperature of the container and the temperature change rate of the container for transporting lithium batteries; wherein the lithium battery exhaust rate is the rate at which all the cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; the initial temperature of the container is the temperature inside the container after the lithium battery is loaded; the temperature change rate is the rate at which the temperature inside the container rises after all the cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway;

[0029] A first exhaust wind speed calculation module is used to calculate a first exhaust wind speed according to the exhaust rate of the lithium battery and the remaining volume of the container; the first exhaust wind speed represents the wind speed required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container;

[0030] A first ventilation area calculation module is used to calculate a first ventilation area according to the lithium battery exhaust rate and the first exhaust wind speed; the first ventilation area represents the ventilation port area required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container;

[0031] A gas expansion rate calculation module, used to calculate the gas expansion rate according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; the gas expansion rate is the rate at which the gas in the container expands after all the cells in any packaging unit loaded in the container completely experience thermal runaway, causing the temperature in the container to rise;

[0032] A second exhaust wind speed calculation module is used to calculate a second exhaust wind speed according to the gas expansion rate and the remaining volume of the container; the second exhaust wind speed represents the wind speed required to balance the increased pressure inside the container caused by the expansion of the gas in the container;

[0033] A second ventilation area calculation module is used to calculate a second ventilation area according to the gas expansion rate and the second exhaust wind speed; the second ventilation area represents the ventilation port area required to balance the increased pressure inside the container caused by the expansion of the gas in the container;

[0034] A total area calculation module is used to obtain the ventilation area of ​​the container according to the first ventilation area and the second ventilation area.

[0035] In order to solve the above technical problems, the present invention also provides an electronic device, including a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method for calculating the ventilation opening area of ​​a container for transporting lithium batteries as described above is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a flow chart of a method for calculating the ventilation opening area of ​​a container for transporting lithium batteries according to the present invention;

[0037] Figure 2 The figure is a schematic diagram of a ventilation opening area calculation system for a container for transporting lithium batteries according to the present invention. DETAILED DESCRIPTION

[0038] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0039] Embodiment 1

[0040] like Figure 1 The present embodiment provides a method for calculating the ventilation area of ​​a container for transporting lithium batteries, including: obtaining the lithium battery exhaust rate, the remaining volume of the container, the initial temperature of the container and the temperature change rate of the container for transporting lithium batteries; wherein the lithium battery exhaust rate is the rate at which all battery cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; the initial temperature of the container is the temperature inside the container after the lithium batteries are loaded; the temperature change rate is the rate at which the temperature inside the container rises after all battery cells in any packaging unit loaded in the container are completely thermal runaway; according to the lithium battery exhaust rate and the remaining volume of the container, a first exhaust wind speed is calculated; the first exhaust wind speed represents the wind speed required to exhaust the gas released by all battery cells in any packaging unit loaded in the container due to thermal runaway from the container; according to the lithium battery exhaust rate and the first exhaust wind speed, a first ventilation area is calculated; the first ventilation area The wind area represents the ventilation area required to discharge the gas released by all the battery cells in any packaging unit loaded in the container due to complete thermal runaway from the container; the gas expansion rate is calculated according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; the gas expansion rate is the rate of expansion of the gas in the container after all the battery cells in any packaging unit loaded in the container have completely thermal runaway and cause the temperature in the container to rise; the second exhaust wind speed is calculated according to the gas expansion rate and the remaining volume of the container; the second exhaust wind speed represents the wind speed required to balance the increased pressure inside the container caused by the expansion of the gas in the container; the second ventilation area is calculated according to the gas expansion rate and the second exhaust wind speed; the second ventilation area represents the ventilation area required to balance the increased pressure inside the container caused by the expansion of the gas in the container; the ventilation area of ​​the container is obtained according to the first ventilation area and the second ventilation area.

[0041] The container is loaded with several packaging units, such as packaging boxes. The packaging unit is used to load lithium batteries, which contain battery cells. If a packaging unit has thermal runaway, it can be exhausted through the container vents. If more packaging units have thermal runaway, the container cannot withstand it and needs to solve the thermal runaway problem in other ways. Therefore, when designing the vent area, only considering that all the battery cells in one packaging unit have completely thermal runaway can meet the usage requirements.

[0042] This method considers the calculation of ventilation area from two aspects. On the one hand, thermal runaway of lithium batteries produces a large amount of gas, which leads to an increase in gas in the container. On the other hand, thermal runaway of lithium batteries causes the temperature in the container to rise, which in turn causes the gas in the container to expand and the pressure in the container to increase. Based on the above two aspects, the ventilation area of ​​the lithium battery transport container is calculated. Through this method, the ventilation area of ​​the container can be calculated more accurately, which can ensure that the lithium battery can be exhausted smoothly when thermal runaway occurs, while reducing the impact of the ventilation opening on the function of the container itself.

[0043] Optionally, in an embodiment, the lithium battery exhaust rate is obtained in the following manner: obtaining the number of battery cells contained in any packaging unit in which thermal runaway has completely occurred, the battery cell capacity, the amount of battery cell gas released, and the lithium battery exhaust time; calculating the lithium battery gas release volume based on the number of battery cells contained in the packaging unit, the battery cell capacity, and the battery cell gas release amount; calculating the lithium battery exhaust rate based on the lithium battery gas release volume and the lithium battery exhaust time.

[0044] The number of battery cells contained in the packaging unit, the battery cell capacity, the battery cell gas release amount and the lithium battery exhaust time can all be queried based on parameters such as the battery cell model used to load the container.

[0045] Optionally, in an embodiment, the battery cell gas release amount is the battery cell gas release amount corresponding to when a battery cell with a state of charge of 40% completely experiences thermal runaway.

[0046] During the transportation of lithium batteries, the state of charge (SOC) of the battery cell cannot exceed 40%. A battery cell with an SOC exceeding 40% may experience thermal runaway and catch fire, while a battery cell with an SOC below 40% will only emit smoke but not catch fire when it experiences thermal runaway. Therefore, the vent area is calculated using the corresponding gas release amount of a battery cell with a SOC of 40% when it experiences thermal runaway.

[0047] Optionally, in an embodiment, the calculating the first exhaust wind speed according to the lithium battery exhaust rate and the remaining volume of the container includes:

[0048] According to the exhaust rate of the lithium battery and the remaining volume of the container, a first pressure change rate is calculated by a first formula, wherein the first pressure change rate is a rate at which the pressure in the container changes due to the gas released by all the cells in any packaging unit loaded in the container due to complete thermal runaway;

[0049] The first formula is: ;

[0050] in, refers to the first pressure change rate, Refers to atmospheric pressure, Refers to the exhaust rate of lithium batteries, Refers to the remaining volume of the container;

[0051] Calculating the first exhaust wind speed by a second formula according to the first pressure change rate;

[0052] The second formula is: ;

[0053] in, Refers to the first row wind speed, Refers to the carbon monoxide density of the air.

[0054] Optionally, in an embodiment, the calculating the first ventilation area according to the lithium battery exhaust rate and the first exhaust wind speed includes: calculating a first ratio of the lithium battery exhaust rate to the first exhaust wind speed, and determining the first ratio as the first ventilation area. That is, the first ventilation area = battery cell exhaust rate / first exhaust wind speed.

[0055] Optionally, in an embodiment, the calculating the gas expansion rate according to the remaining volume of the container, the initial temperature of the container and the temperature change rate includes: calculating the gas expansion rate by a third formula according to the remaining volume of the container, the initial temperature of the container and the temperature change rate;

[0056] The third formula is: ;

[0057] in, The gas expansion rate, Refers to the remaining volume of the container. The rate of temperature change, Refers to the initial temperature of the container.

[0058] The theoretical basis of the third formula is: According to the gas equation PV=nRT, the relationship between gas pressure and temperature can be obtained, that is, (P2V2) / (P1V1)=T2 / T1.

[0059] If the internal pressure of the container is kept constant, the third formula can be obtained as follows: .

[0060] Optionally, in an embodiment, the calculating the second exhaust wind speed according to the gas expansion rate and the remaining volume of the container includes: calculating a second pressure change rate according to the gas expansion rate and the remaining volume of the container by a fourth formula, wherein the second pressure change rate is a rate of change of the internal pressure of the container caused by the expansion of the gas in the container;

[0061] The fourth formula is: ;

[0062] in, refers to the second pressure change rate, Refers to atmospheric pressure, The gas expansion rate, Refers to the remaining volume of the container;

[0063] Calculating the second exhaust wind speed by a fifth formula according to the second pressure change rate;

[0064] The fifth formula is: ;

[0065] in, Refers to the second row wind speed, Refers to the carbon monoxide density of the air.

[0066] The theoretical basis of the first and fourth formulas is:

[0067] According to Avogadro's law and the gas equation PV=nRT, for gas at the same temperature and volume, the pressure is proportional to the amount of substance, that is, P1 / P2=n1 / n2.

[0068] The amount of gas substance is equal to the ratio of the gas volume to the gas molar volume, that is, n=V / V m At the same temperature and pressure, the gas molar volume of any gas is the same. According to Table 1, when the temperature changes very little, the gas molar volume also changes very little.

[0069] Table 1 Correspondence between molar volume and temperature of air gas

[0070]

[0071] Based on the above information, at the same temperature and volume, we can deduce that gas P1 / P2=n1 / n2=V1 / V2.

[0072] The theoretical basis of the second and fifth formulas is the Bernoulli equation .

[0073] Optionally, in an embodiment, the calculating the second ventilation area according to the gas expansion rate and the second exhaust wind speed includes: calculating a second ratio of the gas expansion rate to the second exhaust wind speed, and determining the second ratio as the second ventilation area. That is, the second ventilation area = gas expansion rate / second exhaust wind speed.

[0074] Optionally, in an embodiment, obtaining the vent area of ​​the lithium battery transport container according to the first ventilation area and the second ventilation area includes: summing the first ventilation area and the second ventilation area to obtain the vent area of ​​the lithium battery transport container. That is, the vent area of ​​the lithium battery transport container = the first ventilation area + the second ventilation area.

[0075] In the calculation of the ventilation area of ​​the container for transporting lithium batteries, according to the model of lithium batteries loaded in the container, the model of the container, the transportation requirements, etc., the number of battery cells in the packaging unit, the battery cell capacity, the battery cell gas release, the lithium battery exhaust time, the remaining volume of the container, the initial temperature of the container, the temperature change rate, etc. are queried or determined, and then the ventilation area of ​​the lithium battery transport container is calculated step by step according to the above method to achieve a reasonable design of the container ventilation area.

[0076] Embodiment 2

[0077] like Figure 2 As shown, this embodiment provides a system for calculating the ventilation opening area of ​​a container for transporting lithium batteries, including:

[0078] An acquisition module is used to acquire the lithium battery exhaust rate, the remaining volume of the container, the initial temperature of the container and the temperature change rate of the container for transporting lithium batteries; wherein the lithium battery exhaust rate is the rate at which all the cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; the initial temperature of the container is the temperature inside the container after the lithium battery is loaded; the temperature change rate is the rate at which the temperature inside the container rises after all the cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway;

[0079] A first exhaust wind speed calculation module is used to calculate a first exhaust wind speed according to the exhaust rate of the lithium battery and the remaining volume of the container; the first exhaust wind speed represents the wind speed required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container;

[0080] A first ventilation area calculation module is used to calculate a first ventilation area according to the lithium battery exhaust rate and the first exhaust wind speed; the first ventilation area represents the ventilation port area required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container;

[0081] A gas expansion rate calculation module, used to calculate the gas expansion rate according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; the gas expansion rate is the rate at which the gas in the container expands after all the cells in any packaging unit loaded in the container completely experience thermal runaway, causing the temperature in the container to rise;

[0082] A second exhaust wind speed calculation module is used to calculate a second exhaust wind speed according to the gas expansion rate and the remaining volume of the container; the second exhaust wind speed represents the wind speed required to balance the increased pressure inside the container caused by the expansion of the gas in the container;

[0083] A second ventilation area calculation module is used to calculate a second ventilation area according to the gas expansion rate and the second exhaust wind speed; the second ventilation area represents the ventilation port area required to balance the increased pressure inside the container caused by the expansion of the gas in the container;

[0084] A total area calculation module is used to obtain the ventilation area of ​​the container according to the first ventilation area and the second ventilation area.

[0085] Get modules, including:

[0086] An acquisition unit, used to obtain the number of cells, cell capacity, cell gas release amount, and lithium battery exhaust time contained in any packaging unit that has completely experienced thermal runaway;

[0087] A lithium battery gas release volume calculation unit, used to calculate the lithium battery gas release volume according to the number of battery cells contained in the packaging unit, the battery cell capacity and the battery cell gas release amount;

[0088] The lithium battery exhaust rate calculation unit is used to calculate the lithium battery exhaust rate according to the lithium battery gas release volume and the lithium battery exhaust time.

[0089] The cell gas release amount is the cell gas release amount corresponding to when a cell with a state of charge of 40% completely experiences thermal runaway.

[0090] The first row wind speed calculation module includes:

[0091] A first pressure change rate calculation unit, used to calculate a first pressure change rate by a first formula according to the exhaust rate of the lithium battery and the remaining volume of the container, wherein the first pressure change rate is a rate at which the pressure in the container changes due to the gas released by all the cells in any packaging unit loaded in the container due to complete thermal runaway;

[0092] The first formula is: ;

[0093] in, refers to the first pressure change rate, Refers to atmospheric pressure, Refers to the exhaust rate of lithium batteries, Refers to the remaining volume of the container;

[0094] A first exhaust wind speed calculation unit, configured to calculate the first exhaust wind speed by a second formula according to the first pressure change rate;

[0095] The second formula is: ;

[0096] in, Refers to the first row wind speed, Refers to the carbon monoxide density of the air.

[0097] The first ventilation area calculation module includes: a first ventilation area calculation unit, which is used to calculate a first ratio of the lithium battery exhaust rate to the first exhaust wind speed, and determine the first ratio as the first ventilation area.

[0098] The gas expansion rate calculation module includes: a gas expansion rate calculation unit, configured to calculate the gas expansion rate by a third formula according to the remaining volume of the container, the initial temperature of the container and the temperature change rate;

[0099] The third formula is: ;

[0100] in, The gas expansion rate, Refers to the remaining volume of the container. The rate of temperature change, Refers to the initial temperature of the container.

[0101] The second row wind speed calculation module includes:

[0102] a second pressure change rate calculation unit, configured to calculate a second pressure change rate by a fourth formula according to the gas expansion rate and the remaining volume of the container, wherein the second pressure change rate is a rate of change of the pressure inside the container caused by the expansion of the gas in the container;

[0103] The fourth formula is: ;

[0104] in, refers to the second pressure change rate, Refers to atmospheric pressure, The gas expansion rate, Refers to the remaining volume of the container;

[0105] A second exhaust wind speed calculation unit, configured to calculate the second exhaust wind speed according to the second pressure change rate by using a fifth formula;

[0106] The fifth formula is: ;

[0107] in, Refers to the second row wind speed, Refers to the carbon monoxide density of the air.

[0108] The second ventilation area calculation module includes: a second ventilation area calculation unit, which is used to calculate a second ratio of the gas expansion rate to the second exhaust wind speed, and determine the second ratio as the second ventilation area.

[0109] Embodiment 3

[0110] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, a method for calculating the ventilation opening area of ​​a container for transporting lithium batteries as described in Embodiment 1 is implemented.

[0111] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0112] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0113] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0114] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0115] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0116] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for calculating the ventilation area of ​​a container for transporting lithium batteries, characterized in that: include: Obtain the lithium battery exhaust rate, remaining volume of the container, initial temperature of the container and temperature change rate of the container for transporting lithium batteries; wherein the lithium battery exhaust rate is the rate at which all cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; the initial temperature of the container is the temperature inside the container after the lithium battery is loaded; the temperature change rate is the rate at which the temperature inside the container rises after all cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; Calculate a first exhaust wind speed according to the exhaust rate of the lithium battery and the remaining volume of the container; the first exhaust wind speed represents the wind speed required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container; A first ventilation area is calculated according to the lithium battery exhaust rate and the first exhaust wind speed; the first ventilation area represents the ventilation area required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container; The gas expansion rate is calculated according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; the gas expansion rate is the rate at which the gas in the container expands after all the cells in any packaging unit loaded in the container completely experience thermal runaway, causing the temperature in the container to rise; Calculating a second exhaust wind speed according to the gas expansion rate and the remaining volume of the container; the second exhaust wind speed represents the wind speed required to balance the increased pressure inside the container caused by the expansion of the gas in the container; Calculating a second ventilation area according to the gas expansion rate and the second exhaust wind speed; the second ventilation area represents the ventilation area required to balance the increased pressure inside the container caused by the expansion of the gas in the container; The ventilation opening area of ​​the container is obtained according to the first ventilation area and the second ventilation area.

2. According to the method for calculating the ventilation opening area of ​​a container for transporting lithium batteries according to claim 1, it is characterized in that: The lithium battery exhaust rate is obtained by: Obtain the number of cells, cell capacity, cell gas release, and lithium battery exhaust time contained in any packaging unit that has completely experienced thermal runaway; Calculating the gas release volume of the lithium battery according to the number of battery cells contained in the packaging unit, the battery cell capacity and the gas release amount of the battery cell; The exhaust rate of the lithium battery is calculated according to the gas release volume of the lithium battery and the exhaust time of the lithium battery.

3. According to claim 2, a method for calculating the ventilation opening area of ​​a container for transporting lithium batteries is characterized in that: The cell gas release amount is the cell gas release amount corresponding to when a cell with a state of charge of 40% completely experiences thermal runaway.

4. According to the method for calculating the ventilation opening area of ​​a container for transporting lithium batteries as described in claim 1, it is characterized in that: The calculating the first exhaust wind speed according to the exhaust rate of the lithium battery and the remaining volume of the container includes: According to the exhaust rate of the lithium battery and the remaining volume of the container, a first pressure change rate is calculated by a first formula, wherein the first pressure change rate is a rate at which the pressure in the container changes due to the gas released by all the cells in any packaging unit loaded in the container due to complete thermal runaway; The first formula is: ; in, refers to the first pressure change rate, Refers to atmospheric pressure, Refers to the exhaust rate of lithium batteries, Refers to the remaining volume of the container; Calculating the first exhaust wind speed by a second formula according to the first pressure change rate; The second formula is: ; in, Refers to the first row wind speed, Refers to the carbon monoxide density of the air.

5. According to the method for calculating the ventilation opening area of ​​a container for transporting lithium batteries as described in claim 1, it is characterized in that: The calculating the first ventilation area according to the lithium battery exhaust rate and the first exhaust wind speed includes: A first ratio of the lithium battery exhaust rate to the first exhaust wind speed is calculated, and the first ratio is determined as the first ventilation area.

6. According to claim 1, a method for calculating the ventilation opening area of ​​a container for transporting lithium batteries is characterized in that: The calculating the gas expansion rate according to the remaining volume of the container, the initial temperature of the container and the temperature change rate comprises: Calculating a gas expansion rate by a third formula according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; The third formula is: ; in, The gas expansion rate, Refers to the remaining volume of the container. The rate of temperature change, Refers to the initial temperature of the container.

7. The method for calculating the ventilation opening area of ​​a container for transporting lithium batteries according to claim 1, characterized in that: The calculating the second exhaust wind speed according to the gas expansion rate and the remaining volume of the container includes: Calculate a second pressure change rate according to the gas expansion rate and the remaining volume of the container by using a fourth formula, wherein the second pressure change rate is a rate of change of the pressure inside the container caused by the expansion of the gas in the container; The fourth formula is: ; in, refers to the second pressure change rate, Refers to atmospheric pressure, The gas expansion rate, Refers to the remaining volume of the container; Calculating the second exhaust wind speed by a fifth formula according to the second pressure change rate; The fifth formula is: ; in, Refers to the second row wind speed, Refers to the carbon monoxide density of the air.

8. The method for calculating the ventilation opening area of ​​a container for transporting lithium batteries according to claim 1, characterized in that: The calculating the second ventilation area according to the gas expansion rate and the second exhaust wind speed comprises: A second ratio of the gas expansion rate to the second exhaust wind speed is calculated, and the second ratio is determined as the second ventilation area.

9. A system for calculating the ventilation opening area of ​​a container for transporting lithium batteries, characterized in that: include: An acquisition module is used to acquire the lithium battery exhaust rate, the remaining volume of the container, the initial temperature of the container and the temperature change rate of the container for transporting lithium batteries; wherein the lithium battery exhaust rate is the rate at which all the cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; the initial temperature of the container is the temperature inside the container after the lithium battery is loaded; the temperature change rate is the rate at which the temperature inside the container rises after all the cells in any packaging unit loaded in the container are completely exhausted due to thermal runaway; A first exhaust wind speed calculation module is used to calculate a first exhaust wind speed according to the exhaust rate of the lithium battery and the remaining volume of the container; the first exhaust wind speed represents the wind speed required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container; A first ventilation area calculation module is used to calculate a first ventilation area according to the lithium battery exhaust rate and the first exhaust wind speed; the first ventilation area represents the ventilation port area required to exhaust the gas released by all the cells in any packaging unit loaded in the container due to thermal runaway from the container; A gas expansion rate calculation module, used to calculate the gas expansion rate according to the remaining volume of the container, the initial temperature of the container and the temperature change rate; the gas expansion rate is the rate at which the gas in the container expands after all the cells in any packaging unit loaded in the container completely experience thermal runaway, causing the temperature in the container to rise; A second exhaust wind speed calculation module is used to calculate a second exhaust wind speed according to the gas expansion rate and the remaining volume of the container; the second exhaust wind speed represents the wind speed required to balance the increased pressure inside the container caused by the expansion of the gas in the container; A second ventilation area calculation module is used to calculate a second ventilation area according to the gas expansion rate and the second exhaust wind speed; the second ventilation area represents the ventilation port area required to balance the increased pressure inside the container caused by the expansion of the gas in the container; A total area calculation module is used to obtain the ventilation area of ​​the container according to the first ventilation area and the second ventilation area.

10. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, a method for calculating the ventilation opening area of ​​a container for transporting lithium batteries as described in any one of claims 1 to 8 is implemented.

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