container

Abstract

Container (1) for at least one rechargeable electrochemical energy storage device, in particular a lithium-ion battery, comprising a lockable housing (10) which encloses a receiving space (17) for the at least one battery, wherein the housing (10) is designed with ventilation openings (6), characterized in that a labyrinth seal (2) is provided in the receiving space (17) covering the ventilation openings (6) and consisting of at least two sealing hoods (20, 21) arranged one above the other with a passage gap (200), wherein each sealing hood (20, 21) comprises a substantially rectangular cover plate (22) with longitudinal sides and shorter transverse sides and is provided along the longitudinal sides and one of the two transverse sides with side walls (23, 24, 25) projecting at an angle from the cover plate, which rest on the inside of the housing (10),wherein the further sealing hood (21) arranged above a sealing hood (20) overlaps the sealing hood (20) arranged below it and the open transverse sides (26) of the sealing hoods (20, 21), each designed without side walls, are alternately oriented towards each other in opposite directions.

Description

[0001] The invention relates to a container for at least one electrochemical energy storage device, in particular a rechargeable lithium-ion battery, as is established as an energy storage device for household and work appliances, e-bikes and much more, comprising a lockable housing which encloses a receiving space for the at least one battery, wherein the housing is designed with ventilation openings.

[0002] Lithium-ion batteries, also referred to as Li-ion batteries, can spontaneously combust, especially during charging, a phenomenon known as thermal runaway. To prevent a battery fire from spreading to the building, Li-ion batteries should only be charged and stored in suitable containers. Containers designed as safety boxes are particularly compact and therefore have a small volume. During thermal runaway, large quantities of reaction gases are produced, which, if not vented, lead to high pressures inside the container. Furthermore, if the gases cannot escape, an explosive gas mixture can potentially form inside the container. Therefore, the pressure must be able to escape with as little resistance as possible through the ventilation openings in the housing. Due to the partially explosive combustion of the reaction gases, the resulting flames are relatively long-lasting.However, flames, sparks, and burning components must never leave the container. Otherwise, there is a risk that they will ignite surrounding furnishings.

[0003] The object of the invention is therefore to propose a container of the aforementioned type in which, in the simplest possible way, it is reliably prevented that flames and sparks as well as glowing components can escape through the ventilation openings despite the compact design of the container.

[0004] To solve the stated problem, the invention proposes that a labyrinth seal consisting of at least two sealing hoods arranged one above the other, leaving a passage gap, is provided in the receiving space, covering the ventilation openings, wherein each sealing hood comprises a substantially rectangular cover plate with longitudinal sides and shorter transverse sides and is provided along the longitudinal sides and one of the two transverse sides with side walls projecting at an angle from the cover plate, which rest on the inside of the housing, wherein the further or upper sealing hood arranged above a lower sealing hood overlaps the lower sealing hood arranged below it, and the open transverse sides of the sealing hoods, each designed without side walls, are alternately aligned in opposite directions to each other.

[0005] According to the invention, a labyrinth seal is created that prevents flame penetration while simultaneously allowing gas exchange. This is achieved by stacking at least two very simple-to-manufacture sealing hoods with circumferential side walls, which are open on one of their short transverse sides, one above the other at a distance from each other, with their side walls resting against the inside of the housing. The alternating orientation of the open transverse side creates a labyrinth, and flames and gases penetrate through the open transverse side of the uppermost sealing hood into the space enclosed by this hood and the inside of the housing, in which the at least one covered lower sealing hood is also located. Transit into this covered lower sealing hood occurs at the closed transverse side of the uppermost sealing hood, where the open transverse side of the covered sealing hood is located.As the gases travel through the spaces enclosed by the sealing chambers with side walls and the inside of the housing, their direction reverses, thus lengthening the path so significantly that any flames that might form cannot bridge this gap. At the end opposite the open transverse side of the covered sealing hood, this hood is also closed along that transverse side by a side wall and can lie over and communicate with the ventilation opening in this area. Gases can therefore easily reach and be discharged through the ventilation openings, but flames and any glowing particles are reliably prevented from escaping through them, as they do not reach the ventilation opening located at the end of the labyrinth seal (viewed from the outflow direction) on their extended path through the labyrinth seal.

[0006] According to one proposal of the invention, the lowermost sealing hood is designed with shorter longitudinal and transverse sides than the sealing hood arranged above it.

[0007] For a simple and quick arrangement of the sealing hoods one above the other, a further proposal of the invention suggests holding the sealing hoods spaced apart from each other by means of spacer sleeves, forming the passage gap.

[0008] Since the lithium-ion batteries can also be charged in the container according to the invention, the heat generated during charging must be dissipated from the container. According to a further aspect of the invention, the housing is provided with at least two ventilation openings and associated labyrinth seals, one of which is equipped with a fan. The fan creates air circulation inside the container according to the invention, thus dissipating the heat generated.

[0009] In order to utilize the entire width of the rear wall and thus maximize the length of the flame channel / labyrinth, a further proposal of the invention suggests that the housing has a rear wall in which the ventilation openings are formed, wherein the ventilation openings are arranged with an offset to each other.

[0010] According to another suggestion of the invention, the container can be equipped with a power connection and power strips arranged in the receiving space.

[0011] Sensors or sensor devices may also be provided to detect an impending thermal runaway of an energy storage device located in the receiving room and, for example, trigger an alarm via an alarm system.

[0012] Further details of the invention are explained below with reference to the drawing illustrating an exemplary embodiment. The drawing shows: Fig. 1: in perspective view the front view of a container according to the invention; Fig. 2: a section through the container according to the invention Fig. 1; Fig. 3: a perspective view through the transparently depicted back wall of the container according to Fig. 1 into the receiving area of ​​the container.

[0013] The figures show a container marked with reference numeral 1, which in the illustrated embodiment is adapted in size to the dimensions of a commercially available lithium-ion battery for an e-bike.

[0014] The container 1 comprises a frame formed, in the illustrated embodiment, of extruded aluminum profiles, with plate components arranged between the profiles, which together form a closed housing 10 and define a receiving space 17 for the accumulator. The receiving space 17 of the container 1 is accessible via an openable and closable door 19, and the rear wall of the container 1 is marked with reference numeral 18.

[0015] A battery placed in the receiving compartment 17 can be supplied with charging current via sockets arranged in the receiving compartment 17 (not shown in detail), i.e. the battery is usually arranged together with the associated charger in the receiving compartment 17 of the container 1.

[0016] In the area of ​​the rear wall 18 of the housing 10, two ventilation openings 6 are provided as perforations in the rear wall 18, arranged with the greatest possible offset from each other, as can be seen, for example, from the Fig. Figure 3 shows a representation of the container 1 with the back wall 18 shown in transparent detail.

[0017] Regarding the representation according to Fig. 3. Through the ventilation opening 6 shown at the bottom left, which is covered with a grille, fresh air from the outside of the container 1 can enter the interior 17 and in the opposite direction via the opening shown in the illustration. Fig. The air is discharged from the receiving chamber 17 through the ventilation opening 6 shown in the upper right, whereby a motor-driven fan 60 is mounted on the latter ventilation opening 6 to force the generation of such a directed airflow.

[0018] The purpose of the container 1 shown is to safely store the accumulator within the receiving space 17, which is sealed off from the environment by the housing 10, and, for example, to prevent the accumulator, which may catch fire or, in the worst case, explode, from setting the surroundings on fire either through escaping flames or flying debris in the event of a thermal runaway.

[0019] To prevent flames from escaping from the receiving chamber 17 into the environment, a labyrinth seal 2 is applied to the rear wall 18 and the two ventilation openings 6 in the area of ​​the inside of the housing 10, i.e. facing the receiving chamber 17, and is fixed, for example, with screws.

[0020] The two labyrinth seals 2 are each formed by two sealing hoods 20, 21 arranged one above the other, which are made, for example, of metal sheets and have a substantially rectangular outline and are arranged one above the other in a horizontal orientation in front of the respective ventilation openings 6 shown in the illustrated embodiment.

[0021] Each sealing cap 20, 21 comprises a substantially rectangular cover plate 22 with longer longitudinal sides and correspondingly shorter transverse sides, wherein a side wall 23, 24, 25 is welded or angled along each of the longitudinal sides and one of the two transverse sides, its respective free edge facing away from the cover plate 22 resting flush and sealingly against the inside of the rear wall 18. By way of example only, the side walls 23, 24 and 25 can each form an angle of 40 to 50° with the associated cover plate 22.

[0022] As can be seen in particular from the Fig. As can be seen in Figure 2, in each labyrinth seal 2, viewed from the rear wall 18, one sealing cap 20 is arranged below the second sealing cap 21, which overlaps it. This means that the upper sealing cap 21 is longer and wider than the lower sealing cap 20, so that it can completely cover the lower sealing cap 20. A continuous passage gap 200 is thus formed between the two sealing caps 20, 21 of the respective labyrinth seal 2, and this gap is fixed by placing spacers 27 between the respective cover plates 22.

[0023] Furthermore, each sealing hood 20, 21 is open on its transverse side 26 opposite the closed transverse side formed with side wall 24, with the two open transverse sides 26 of the sealing hoods 20, 21 being alternately oriented in opposite directions to each other. This arrangement allows gas exchange between the covered ventilation openings 6 and the receiving chamber 17 of the housing 10 in both directions. Gaseous components from the receiving chamber 17 enter according to arrow P1. Fig. 3 first enter the passage gap 200 between the two cover plates 22 of the sealing hoods 21, 20 via the open transverse side 26 of the sealing hood 21 and flow along it to the side wall 24. At this closed transverse side of the sealing hood 21, the gaseous components then flow in the direction of arrow P2. Fig.3. The gas flows through the open transverse side 26 of the lowermost sealing hood 20 into the passage gap 200 between the associated cover plate 22 and the rear wall 18, and from there back in the opposite direction to the inlet until it reaches the ventilation opening 6, from where it is blown into the environment via the fan 60. In the opposite direction, the gas flows through the lower ventilation opening 6 along the lowermost sealing hood 20 of the lower labyrinth seal 2, then into the passage gap 200 between the lower sealing hood 20 and the sealing hood 21 above it, until the gas flow enters the receiving chamber 17 of the container 1 via the open transverse side 26 of the sealing hood 21.

[0024] This roughly zigzag-shaped flow pattern is followed not only by fresh gases, but also, in the opposite direction, by the smoke gases generated inside the container 1 in the event of a fire. In this way, they are vented to the surroundings without causing an excessive pressure increase inside the container 1. At the same time, the path traveled through the respective labyrinth seal 2 is lengthened to such an extent that the escape of flames occurring in the receiving chamber 17 into the surroundings via the ventilation openings 6 is reliably prevented. The smoke gases can thus escape freely, while flames cannot reach the ventilation openings 6 of the housing 10 due to the length of the passage gap 200 through the labyrinth seals 2.

[0025] Due to the horizontal orientation of the labyrinth seals 2 with the associated sealing hoods 20, 21, a maximum length of the passage gap 200 is achieved.

[0026] It is understood that the container 1 described above may also be equipped with further sensor devices in the interior for monitoring temperatures, possible occurrence of combustion gases, etc., and may also be equipped with alarm devices controlled by such sensor devices, for example optical and acoustic warning devices to indicate a thermal runaway of an accumulator located in the receiving compartment 17. Reference symbol list: 1 container 2 Labyrinth seal 6 ventilation openings 10 cases 17 Recording room 18 Back panel 19 Door 20 sealing caps 21 Sealing cap 22 Cover plate 23 Side wall 24 side wall 25 side wall 26 open transverse side 27 Spacer sleeve 60 fans 200 passage gap

Claims

Container (1) for at least one rechargeable electrochemical energy storage device, in particular a lithium-ion battery, comprising a lockable housing (10) which encloses a receiving space (17) for the at least one battery, wherein the housing (10) is designed with ventilation openings (6), characterized in that a labyrinth seal (2) is provided in the receiving space (17) covering the ventilation openings (6) and consisting of at least two sealing hoods (20, 21) arranged one above the other with a passage gap (200), wherein each sealing hood (20, 21) comprises a substantially rectangular cover plate (22) with longitudinal sides and shorter transverse sides and is provided along the longitudinal sides and one of the two transverse sides with side walls (23, 24, 25) projecting at an angle from the cover plate, which rest on the inside of the housing (10),wherein the further sealing hood (21) arranged above a sealing hood (20) overlaps the sealing hood (20) arranged below it and the open transverse sides (26) of the sealing hoods (20, 21), each designed without side walls, are alternately oriented towards each other in opposite directions. Container (1) according to claim 1, characterized in that the sealing hood (20) is designed with shorter longitudinal and transverse sides than the sealing hood (21) arranged above it. Container (1) according to claim 1 or 2, characterized in that the sealing hoods (20, 21) are spaced apart from each other by means of spacer sleeves (27) forming the passage gap (200). Container (1) according to one of claims 1 to 3, characterized in that the housing (10) is provided with at least two ventilation openings (6) and associated labyrinth seals (2), wherein one of the ventilation openings (6) is provided with a fan (60). Container (1) according to one of claims 1 to 4, characterized in that the housing (10) has a rear wall (18) in which the ventilation openings (6) are formed, wherein the ventilation openings (6) are arranged with an offset to each other. Container (1) according to one of claims 1 to 5, characterized in that it is equipped with a power connection and socket strips (4) arranged in the receiving space (17). Container (1) according to one of claims 1 to 6, characterized in that it comprises a sensor device for detecting an impending thermal runaway of an energy storage device arranged in the receiving space.

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