Protective device for an energy store

Abstract

A protective device for an energy store comprises a protective container accommodating the energy store, at least one connection line for a coolant leading into the protective container, and at least one offgas channel leading out from the protective container. The protective device can be used to permanently extinguish a fire in the energy store in the event of a fault without endangering the surroundings.

Description

[0001] Protection device for energy storage

[0002] The subject matter relates to a protective device for energy storage devices, in particular accumulators, and a method for operating such a protective device.

[0003] A variety of technical fields are currently undergoing advancing electrification. This primarily affects electromobility, but also the energy supply to households, production facilities, and many other areas. Often, currently available electrical power must be temporarily stored in energy storage systems for later retrieval. This particularly applies to applications where continuous power supply via the electrical distribution grid is not possible. For example, electric vehicles such as cars, ships, or aircraft must be able to draw on sufficient energy from an energy storage system while they are in motion. But energy storage systems are also increasingly being used in stationary applications, such as in home networks, where energy generated from renewable energy sources, for example, is stored for later retrieval.

[0004] Energy storage systems convert electrical energy into potential energy in a variety of ways. Chemical energy storage systems, particularly accumulators, are widespread. These include, for example, lead, sodium nickel chloride, nickel metal hybrid, and lithium-ion batteries. Other energy storage systems, such as hydrogen tanks in combination with fuel cells, are also known. Potential energy can also be stored in mechanical form, for example, in pumped-storage power plants. However, due to their low energy density and lack of transportability, these are not used in vehicles or households. A common disadvantage of many of these energy storage systems is their destructive potential in the event of a failure. This is because the energy stored in them can be released uncontrollably, instead of being converted into electrical power in a controlled manner. This often leads to the release of a large amount of thermal energy.This thermal energy can reach such enormous levels that parts of the energy storage device and eventually parts of its surroundings catch fire. Emission of hot gases and intense heat are not uncommon in this case.

[0005] Although the risk of ignition of energy storage devices, especially chemical energy storage devices, especially accumulators, is not unknown, the countermeasures commonly used to date do not adequately address this risk. Reports of ignited batteries and the subsequent burnt-out of electric vehicles such as passenger cars, transport vehicles, forklifts and ships are not uncommon. Furthermore, a superficial extinguishing of an energy storage device cannot, in most cases, achieve lasting fire suppression and / or extinguishing. For example, energy storage devices can reignite spontaneously even weeks after apparently successful extinguishing. A characteristic of battery fires is that large quantities of toxic and corrosive gases at extremely high temperatures are emitted very quickly and that high-energy flames occur in the form of flash flames over an extended period.

[0006] This gives rise to the task of minimizing the damage caused by an energy storage device in the event of a fault and, in particular, of protecting people in the immediate vicinity from heat and toxic gases.

[0007] The object is achieved by a protective device for an energy storage device according to claim 1 and a method according to claim 29.

[0008] The following aspects and exemplary embodiments can be freely combined with one another. In particular, the aspects and exemplary embodiments can be combined with one another in accordance with the claims. However, these combinations are not exhaustive. All features disclosed here can be independent of one another and freely combined with one another. The following combinations are merely exemplary and not exhaustive.

[0009] When reference is made to malfunction, error, fire, triggering, activation, or similar events, this may refer to a situation in which at least one battery cell is in thermal runaway or a thermal runaway is imminent. The terms "malfunction," "error," "fire," "trigger," and "activation" can be understood synonymously. It is not necessary for a fire to have already broken out to detect a malfunction. Nor is it necessary for thermal runaway to be underway to detect a malfunction. A malfunction can also be detected through preemptive detection.

[0010] According to one aspect, the protective device comprises a protective housing for an energy storage device. The energy storage device can be housed in an energy storage housing, and the energy storage housing can be housed in the protective housing. The protective housing can also form the energy storage housing. The energy storage device can be formed from a plurality of battery cells. The plurality of battery cells can preferably be electrically interconnected within the housing to form at least one battery module. One or more battery modules in the housing can be electrically connected to at least two terminals arranged on an outer wall of the housing.

[0011] The energy storage device can be, in particular, an electrical energy storage device, in particular a chemical energy storage device, in particular an accumulator. An accumulator can be, for example, a lead, sodium nickel chloride, nickel metal hybrid, or lithium-ion accumulator. Other types of energy storage devices are also possible, for example, a gasoline, hydrogen, or other fuel tank. The energy storage device will subsequently be formed as a battery module with battery cells. However, other energy storage devices also fall under the scope of the present solution. The device described here can be combined with all energy storage devices.

[0012] An electrical energy storage device can have a storage capacity that can be determined by the electrical energy it can absorb. For example, storage capacity can be specified in ampere-hours or watt-hours.

[0013] According to one aspect, the protective device comprises a protective container enclosing the energy storage device housing. A protective container can also be referred to as a protective housing. According to an alternative, the energy storage device housing and the protective container can also be formed by a single housing. When reference is made to the term "protective container" below, this can also refer to the joint housing of the energy storage device and the protective container.

[0014] According to one aspect, the protective device comprises a connecting line for a coolant leading into the protective container. The connecting line can be used to flood the protective container with coolant. The connecting line can comprise a pipe, a hose, a channel, or a similar element suitable for carrying a coolant. The connecting line is particularly suitable for carrying a fluid, in particular water. For this purpose, the connecting line can be designed to be substantially fluid-tight.

[0015] The protective container can be flooded and / or flowed through via the connecting line, in particular with a coolant. In particular, the immediate surroundings of an energy storage device, which is located at least partially within the protective container, can be flooded and / or flowed through. The energy storage device can be cooled in this way.

[0016] The connecting line can, for example, be connected to a fluid supply such as a water pipe. In particular, an existing fluid supply that is not primarily used for firefighting can be used. For example, a domestic water supply, drinking water supply, city water supply, water from the sea, lakes, and / or rivers, the cooling fluid of a cooling system, and many other existing fluid supplies can be easily connected to the protective device in question via the connecting line without any necessary modifications. In particular, existing fluid supplies can be used to operate the protective device in question.

[0017] A coolant can be a liquid, but it can also be a gas. Coolants can be aqueous, especially water, for example, tap water, distilled water, a suspension, aqueous solutions and / or an oil, a foam, and many other liquid coolant forms. A gaseous coolant can, for example, comprise a gas such as nitrogen, CO2, argon, a mixture thereof, or other, preferably inert and / or unreactive gases, which can also be referred to as extinguishing gases.

[0018] According to one aspect, the protective device comprises at least one discharge duct / exhaust gas duct leading out of the protective container. The terms exhaust duct and exhaust duct can be used synonymously. The exhaust duct can preferably be formed for discharging gases, in particular flue gases. The exhaust duct can be formed in such a way that it enables a connection between an interior of the protective container and an environment. The protective container can, for example, be installed in a room. In particular in a garage or a basement. In order to prevent the room and surrounding rooms from being contaminated by flue gases, the exhaust duct preferably runs out of the room, in particular through a wall or ceiling or window towards a

[0019] Fresh air environment, outdoors. This ensures that the immediate vicinity of the protective device remains safe, in particular, that it is not overheated and / or exposed to toxic or otherwise hazardous emissions. Thus, objects in the vicinity of the protective device are protected, and staying in the immediate vicinity remains safe for people.

[0020] The exhaust duct can be formed as part of the protective device. In particular, it can be connected to the receptacle. A connection can be established between the protective container and the surroundings of the room via the exhaust duct. For example, air, steam or smoke, in particular fire gases, can be conducted through the exhaust duct, in particular discharged from the protective container. The exhaust duct can be located in particular in the upper region of the protective container, in particular in the region of a ceiling of the protective container. The exhaust duct can be a chimney, a pipe, a shaft, or another duct which is particularly suitable for conducting gaseous volumes, in particular hot, steam-saturated and / or contaminated gaseous volumes.

[0021] In one embodiment, the exhaust duct may comprise a flame trap, particularly in the area outside the protective container.

[0022] The flame trap can, in particular, comprise a pipe section that changes its orientation multiple times. For example, the flame trap can comprise an at least partially sinusoidal, zigzag, spiral, and / or otherwise curved pipe section. For example, the flame trap can change its orientation at least twice, three times, four times, five times, and / or more often, in particular at so-called changes of direction. A change of direction can mean a pipe section with, for example, a change in pipe orientation by, for example, at least 20°, 30°, 40°, 50°, 70°, 90°, and / or a higher angle. The change of direction can, in particular, extend to a pipe section with a length of, for example, at most half, one time, two times, three times, and / or another multiple of the pipe diameter.For example, a substantially straight piece of pipe can be arranged between at least two of the directional changes of the flame trap. By means of the flame trap, the propagation of flames through the exhaust duct in the area of ​​the flame trap can be at least partially and / or largely and / or completely prevented.

[0023] Alternatively and / or in addition to the flame trap, a diffuser can be provided at an outlet of the exhaust duct, particularly extending from the protective container behind the flame trap. A diffuser can be characterized, for example, by a cross-section that increases in the direction of exhaust air flow. For example, the diffuser can be shaped like a funnel.

[0024] The exhaust duct can have a siphon. The siphon can in particular be a part of the exhaust duct filled with a fluid. For example, the exhaust duct can have a passage from which the exhaust air duct runs against gravity in both directions of the exhaust duct. The siphon can therefore form a local minimum in the height of the exhaust duct. A fluid can be stored in the siphon, which fluid in particular takes up the entire cross-section of the exhaust duct. This ensures that volumes discharged through the exhaust duct are guided through the fluid. The fluid can, for example, cool and / or clean the volumes, for example smoke, steam, toxic gases and other volumes guided through the exhaust duct, and thus make the emissions from the exhaust duct less dangerous for people, technology and the environment.

[0025] The siphon can in particular have a siphon drain for fluids, through which the fluid contained therein can be drained. The drain can be implemented via a siphon drain nozzle in the exhaust duct. This can be attached to the wall defining the exhaust duct, in particular in a fluid-tight manner. The siphon drain can, for example, lead into a collecting volume, for example a collecting tank, a balloon and / or another collecting volume, which can in particular also serve to collect fluid originating from the interior of the protective container. The siphon drain can limit the fill level of the siphon by positioning its outlet at the desired fill level. For example, the siphon drain can have a local maximum at the desired fill level of the siphon. If the fluid level in the siphon exceeds the desired fill level, the fluid is thus drained away via the siphon drain.

[0026] The siphon may further comprise a siphon inlet through which the siphon can be flooded with fluid. In particular, in the case of intense heat dissipated via the exhaust duct, the fluid in the siphon may partially evaporate and / or be expelled from the siphon by a strong flow of volume. A siphon inlet can refill the siphon with fluid. The siphon inlet may, in particular, comprise a valve, in particular a check valve. The valve can regulate the flow of fluid into the siphon and / or prevent backflow from the siphon into the fluid-carrying elements connected to the siphon inlet.

[0027] In one embodiment, the exhaust duct can optionally or cumulatively serve at least partially to discharge liquid fluid. For example, the exhaust duct can be opened and closed via a valve. The liquid fluid can be discharged via the exhaust duct, particularly when the protective container is largely full and fluid is still being supplied through a connecting line. In particular, an outlet for liquid fluids and an outlet for gaseous fluids can be provided in the exhaust duct. For example, the siphon outlet can serve, among other things, to transport liquid fluid out of the exhaust duct. The siphon can thus perform a dual function. Firstly, it cools and cleans the discharged gaseous fluids. Secondly, it separates gaseous and liquid fluids in the exhaust duct.If liquid fluid is transported through the exhaust duct, the siphon inlet can be omitted, since liquid fluid is fed directly from the protective container into the exhaust duct anyway. The exhaust duct can be made at least partially from a heat-resistant and / or fire-resistant material. For example, from metal, a mineral material such as concrete or stone, from glass, ceramic, heat-resistant plastic or similar materials. The shape of at least one of these elements can also be designed so that volumes that are hot, steam-saturated and / or contaminated can be transported through it. This can be achieved in particular by a sufficiently high internal cross-section, for example of at least 1 cm. 2 , 5 cm 2 , 10 cm 2 , 50 cm 2 , 100 cm 2A round or oval cross-section is advantageous for minimizing the internal surface area where deposits can form. Bending radii of these elements can also always be at least 10 cm, 20 cm, 50 cm, 100 cm, or 200 cm. An exhaust duct, for example, can be dimensioned according to the DIN EN 13384 standard.

[0028] According to one aspect, the protective device is formed such that, depending on at least one temperature and / or a gas concentration, in particular a gas concentration of venting gases of the battery cells and / or smoke within the protective container, a valve on the connecting line moves from a first position to a second position and another valve moves from a first position to a second position substantially simultaneously.

[0029] A first position may be an open position. A second position may be a closed position. A first position may be a closed position. A second position may be an open position. The first and / or second position may be a position between an open position and a closed position.

[0030] The first position of the first valve can be the same as the first position of the second valve. The first position of the first valve can be different from the first position of the second valve. The second position of the first valve can be the same as the second position of the second valve. The second position of the first valve can be different from the second position of the second valve. Various actuators are suitable for moving a valve, such as active actuators like motors or magnets or passive actuators like bimetallic elements or springs. These actuators can be controlled by appropriate control means, e.g. electrically, or can react directly to changes in the parameters mentioned above and below, in particular temperature, gas concentration and / or smoke.

[0031] According to an optional embodiment, it has been recognized that at least one connecting line and one further inlet and / or outlet are provided on the protective container. An outlet can be, for example, an exhaust duct. An outlet can be, for example, a drain connection. Furthermore, one or more ventilation openings can be provided. A ventilation opening can be opened and closed by means of at least one valve. This can be done automatically, for example, via a motor. The ventilation opening can be gas-tight and / or liquid-tight.

[0032] The first and second positions of the valves on the connecting line and the other inlets and / or outlets are changed in the event of a fault, particularly to flood the containment vessel with coolant and, if possible, to discharge fire gases from the containment vessel to the atmosphere. This change in the state of the valves should occur essentially simultaneously. First, if flooding is desired, this flooding must be enabled via the connecting line. Therefore, it is recommended that a valve on the connecting line be opened. This opening of the valve on the connecting line floods the interior of the containment vessel with coolant.

[0033] At least the opening of the valve on the connecting line is essential. The other valves are optional. The features disclosed here can all be combined with a configuration in which only the valve on the connecting line is opened. The state of the other valves can be changed, but is neither mandatory nor necessary in the temporal context described below. A change in the valve position can also occur independently of the valve on the connecting line.

[0034] Substantially simultaneously therewith, in one aspect, a second valve on the exhaust passage may be moved from a first position to a second position.

[0035] The exhaust duct can normally be closed, i.e., when the protective container is not flooded. This can be particularly important if the exhaust duct leads outside and the battery stored inside the protective container is to be prevented from being exposed to external environmental influences. This can, in particular, prevent vermin or liquid from entering the protective container and reaching the battery stored there. It is also possible for the exhaust duct to be open under normal conditions and serve as at least a ventilation opening.

[0036] Ventilation openings can be provided on the protective container in order to be able to cool the battery in the protective container during normal operation via convection and / or actively by means of a fan. These ventilation openings serve to supply fresh air to the interior of the protective container. Unlike the exhaust duct, the ventilation openings are generally not led to the outside. This means that in the event of a fire, fire gases from the interior of the protective container can escape through the ventilation openings into the space surrounding the protective container, which, as described above, should be avoided. Therefore, according to one aspect, it is proposed that a valve on at least one ventilation opening of the protective container be moved from a first position to a second position. This can also take place essentially simultaneously.

[0037] The protective container can have an air supply opening and an air exhaust opening for cooling the energy storage device during normal operation. These two openings are open during normal operation. In the event of an alarm or a pre-alarm (as described below), a valve on the air supply opening and the air exhaust opening can be closed, either by the control device or independently. According to one aspect, the protective device comprises at least one sensor. The sensor can be arranged within the protective container. The sensor can be configured to detect at least one parameter. The parameter can be configured to detect temperature and / or gas concentration, in particular a gas concentration of venting gases from the battery cells and / or smoke. Venting gases from a battery cell usually arise before the battery cell catches fire. This is referred to as thermal runaway.If the battery cell enters this state, it will almost inevitably catch fire soon afterward, with seconds or minutes passing between the onset of thermal runaway and the fire actually occurring. This time span can be up to 5 or even 10 minutes, or even significantly longer, e.g., up to an hour or more, or even up to 24 hours. This exact time span can be used to flood the protective container and thus prevent greater damage. This time span can also be used to shut down the storage system, for example, to prevent chemical processes caused by charging that could promote thermal runaway.

[0038] A sensor can, in particular, be a temperature sensor. This allows the temperature inside the protective container to be monitored and allows the detection of any critical temperature values ​​and / or temperature profiles and / or gases by means of appropriate analysis. A temperature sensor is advantageously mounted close to the energy storage device or the battery cells in order to be able to map their temperature as accurately and accurately as possible. A gas sensor can detect dangerous gases at an early stage, and in particular gases that indicate thermal runaway. A pressure sensor can also be provided. This allows dangerous pressures to be detected. A strain sensor, e.g. a strain gauge, can also be arranged on the cells to detect any mechanical changes in the cells. A fill level sensor is another option that can detect, for example, whether and / or to what extent the protective container is filled with fluid.A humidity sensor and / or an optical sensor can also be provided to monitor the interior of the protective container. A pH sensor, for example, can check whether acid from a chemical energy storage device has already penetrated into the fluid, especially the water. A sound and / or vibration sensor can detect any shocks and / or explosions. An acceleration sensor can be used, among other things, to monitor the orientation of the protective container.

[0039] Venting gases can be CO, CO, H, or light alkanes such as CEU, C2H4, C2H6, C3H6, and CsH5. Other gases can be HF, POF3, and PF, or volatile organic compounds (VOCs). The sensor can be used to determine the concentration of at least one of these gases.

[0040] According to one aspect, the protective device comprises at least one evaluation device. According to one embodiment, the evaluation device is coupled to the sensor. The sensor can transmit sensor data to the evaluation device. The evaluation device and sensor can be combined in one device.

[0041] According to one embodiment, it is proposed that the evaluation device detects a malfunction of the energy storage device based on at least one sensor signal. As already described above, a thermal runaway can be a malfunction. A malfunction of the energy storage device can be detected based on a particle concentration of at least one gas, a temperature, or a smoke concentration.

[0042] In a further embodiment, the protective device may comprise a control device. This may, for example, be an electronic circuit, in particular an analog or digital circuit, or a combination of the two. In one embodiment, the control device comprises a processor.

[0043] The control device can be located inside or on the protective container. The advantage of locating it outside the protective container is reduced chemical and thermal stress in the event of overheating and / or a fire in the energy storage device. An insulating layer between the outer wall of the protective container and the control device can protect the latter from damage caused by excessive heat.

[0044] The control device can have its own energy supply, which is in particular independent of the energy storage device.

[0045] The control device can, for example, receive a measured value from at least one sensor. For example, a microcontroller acting as the control device can receive an analog-transmitted measured value from a sensor using an analog-to-digital converter. Measured values ​​can also be received in other ways, for example, digitally.

[0046] The control device can also be configured to control actuators of the protective device. An actuator can be, for example, a valve, for example of a connection and / or drain, a pump, a motor, for example a servo motor, or another actuator. In this way, the control device can, among other things, regulate the fluid flow into and out of the protective container. It is also possible for the protective container to be opened and / or closed using the control device. An actuator can also be configured to trigger another extinguishing device, for example to open a gas valve to allow nitrogen, CO2, and / or another extinguishing gas into the protective container or to activate a fire extinguisher.

[0047] The control device can also control display devices such as a loudspeaker and / or a light source. Particularly in combination with receiving measured values ​​from at least one sensor, this can indicate, for example, detected dangerous operating conditions of the energy storage device, such as overheating and / or a fire. Display devices can have their own power supply or, for example, the power supply of the control device.

[0048] As already explained, the valves can be actively controlled, in particular by means of an actuator. Such an actuator can be understood as a control device.

[0049] The control device can be signal-coupled to the sensor and / or the evaluation device. The control device, the evaluation device, and / or the sensor can also be combined in a single device. As described, the evaluation device can detect an error / malfunction depending on a parameter value. If a malfunction is detected, the evaluation device can trigger the control device. The control device can then, in turn, move a valve from a first position to a second position.

[0050] The flow through the exhaust duct and / or the connection piece can be adjustable using an actuator. For example, a valve can be provided in the exhaust duct / connection piece, in particular a manually and / or electrically / electronically controllable valve. The exhaust duct / connection piece can also be controllable in the same way. The flow through the exhaust duct / connection piece can also be adjusted by controlling a pump of the fluid supply. The flow can be a volume flow. It is proposed that the volume flow through the exhaust duct and / or the connection piece be controlled such that any overpressure within the protective housing remains within predetermined limits.

[0051] According to one aspect, the protective device comprises at least one thermally activated valve. Unlike what has been described above, it is also possible for a valve to be moved by a passive actuator. A passive actuator can be a thermally activated component. In such a case, the sensor and / or evaluation device and / or control device can be omitted. The actuator can simultaneously act as a sensor. This is particularly conceivable with a thermally activated actuator. Here, for example, a bimetallic component can be thermally activated. When the temperature changes, e.g. above a temperature threshold, the component can move the valve from a first position to a second position. It is proposed that the valve moves from a first position to a second position depending on a temperature in the protective container.The advantage is that such passive activation is independent of a power supply and thus remains functional almost indefinitely.

[0052] According to one aspect, the protective device comprises the evaluation device and / or the control device, which are part of a battery management system (BMS) of the battery. The battery cells are typically monitored by a battery management system. This system monitors, for example, the temperature, voltage, and charging and discharging currents of the individual cells. These parameters can also be used to detect thermal runaway.

[0053] According to one aspect, at least one of the valves is controlled by a battery management system (BMS) of the battery. Using the BMS, protection of the space surrounding the battery can be provided cost-effectively. The protective container, including the valve(s), can be retrofitted. A signaling connection to the BMS then makes it easy to flood the protective container.

[0054] According to one aspect, in the event of a detected malfunction, the control device activates at least one switch on one of the connections arranged on the outer wall of the housing. The electrical connections of the battery are routed to the outside of the protective container. In order to de-energize them, the switch can be opened in the event of a malfunction. The switch can be arranged inside the protective container. In a further exemplary embodiment, the energy storage device can be switched off. By switching off the energy storage device, charging and / or discharging and / or other use of the energy storage device can be prevented. In particular, at least one switch can be provided that electrically disconnects the energy storage device from the devices it supplies. This switch can be positioned both inside and outside the protective container.A switch outside the protective container has the advantage that the switch is not exposed to potentially adverse conditions inside in the event of a fault. The switch can be a relay, a triac, a mechanical switch such as a glass bulb, a transistor, a thyristor, or another switch. It can be advantageous to be able to control the switch electronically. In this case, the control device can influence the switch. In particular, the control device can switch, or in particular disconnect, the switch if a malfunction of the energy storage device is detected, particularly in the event of heating and / or ignition. The switch can be opened in the event of a pre-alarm. The switch can be opened if a thermal runaway is detected.

[0055] The control device can shut down the energy storage device and / or disconnect its electrical connection to other devices. In particular, this shutdown and / or disconnection can occur depending on the measured values ​​received from the at least one sensor.

[0056] According to one aspect, the exhaust duct is a ventilation duct for at least flue gases. As already described, the exhaust duct can be used to discharge toxic flue gases to the outside. The exhaust duct can be used exclusively for the discharge of flue gases. The exhaust duct can also be used in combination for flue gases and coolant. The exhaust duct is preferably led through a wall of a room to the outside. In one embodiment, the exhaust duct can be configured to discharge heat, smoke, steam and / or gas from the protective container. In particular, in the case of a heated energy storage device, pressure and / or an elevated temperature can develop within the protective container. The exhaust duct in question can serve to reduce pressure and / or temperature in the protective container by enabling gas exchange with a space other than the protective container.In addition to pressure and temperature, energy storage devices can also emit smoke, gases, particularly toxic gases, and steam. An exhaust duct enables the controlled removal of these substances, some of which are harmful to health and / or other technical equipment. Since the exhaust duct can become very hot, heat protection can be provided for penetrations, particularly through walls, in particular through walls of a building and / or vehicle such as a boat, a car, or similar. For example, a metal plate, insulating material such as rock wool, or other heat-resistant penetrations and / or protective devices can be provided as a penetration. Active cooling can also be achieved, for example by a device that applies a fluid to the exhaust duct, for example by spraying it, allowing it to flow over it, or transporting it there in some other way.

[0057] By means of an exhaust duct, the effects of any heating, fire and / or explosion of a battery cell inside the protective device, outside the protective device and / or outside the room in which the protective device is installed can be minimized and / or substantially avoided.

[0058] According to one aspect, the protective container has a drain connection for draining the coolant. Coolant is fed into the interior of the protective container via the connecting line. The coolant heats up due to the exothermic reaction of the battery cells in the event of a fault. It may be sufficient to completely flood the protective container and then allow the battery cells to cool down. However, it may also be useful to allow coolant to flow around the faulty battery cells after initially flooding the protective container. Therefore, it may be useful to drain the incoming coolant via a drain connection.

[0059] According to one aspect, the drain connection is arranged on or in the exhaust duct. This is particularly advantageous in the case of a siphon, as described above. Thus, both flue gas and coolant can be discharged through an opening within the protective container. The coolant can be fed, for example, to the sewer system via the drain connection, and the flue gases can be discharged to the outside.

[0060] According to one aspect, in the installed position of the protective container, the connecting line is positioned lower than the drain nozzle. The coolant flows into the protective container via the connecting line. If the drain nozzle is positioned higher, the protective container fills with the coolant before it can drain via the drain nozzle. According to one embodiment, the drain nozzle can be arranged in an upper region of the protective container, in particular in the region of the ceiling. According to one aspect, in the installed position of the protective container, the connecting line is positioned higher than the drain nozzle.

[0061] Flue gases generally rise upwards, so it is advisable to discharge them via the exhaust duct near the ceiling. Therefore, the exhaust duct is preferably located higher than the connecting line. According to one embodiment, the exhaust duct can be located in an upper area of ​​the protective container, in particular near the ceiling. It is proposed that the connecting line be located in the lower area of ​​the protective container, in particular near the bottom of the protective container.

[0062] Coolant can be drained out of the protective container via the drain connection. For this purpose, a fluid-carrying and, in particular, fluid-tight connection is provided, at least indirectly, to a target volume, such as at least part of the sewer system, a wastewater, a body of water, a collection tank, a balloon, in particular an elastic balloon, and / or similar target volumes. Since the coolant, in particular water, has been in direct contact with a damaged energy storage device and may be chemically contaminated, it may be advisable for the target volume to be closed, for example, as a collection tank.

[0063] The drain can be equipped with a closure. In particular, a check valve can be arranged in or on the drain to prevent backflow into the protective container. A valve can also be provided. For example, a valve can close and / or open the drain, in particular the drain nozzle.

[0064] To flood the protective vessel, the coolant must be directed into it. The coolant is usually located at the connecting line. Opening a valve on the connecting line allows the coolant to flow into the protective vessel. It is proposed that the control device, when triggered by the evaluation device, move a valve on the connecting line from a closed position to an open position. This valve ensures that the protective vessel is not flooded under normal conditions, but that the coolant can flow into the protective vessel in the event of a fault.

[0065] If a thermal runaway occurs, the battery cells may still be charged. This means that electrical charge is stored in the battery cells. In the event of a fault, this charge can lead to high currents via short circuits within the battery cells, which further accelerate a thermal runaway. In order to discharge the battery cells as quickly as possible, it is recommended that the coolant be mixed with salt. To ensure that the coolant is reliably mixed with salt in the event of flooding, it is recommended that at least one salt depot be arranged in the protective container and / or in the connecting line. The connecting line can be designed so that the coolant flows around the salt in the salt depot during flooding and is thus mixed with salt. The salt depot can also be arranged in the protective container. The coolant flowing into the protective container then comes into contact with the salt and dissolves it.It is suggested that the salt deposit be a NaCl deposit. The salt is dissolved by the coolant. The conductivity of the coolant is increased, and the battery cells thus discharge faster.

[0066] According to one aspect, it is proposed that the salt deposit be passive. This means that the coolant flows around the salt and is dissolved by the flowing coolant. On the other hand, the salt deposit can be active. The control device can activate the salt deposit so that salt, either solid or in dissolved form, is added to the coolant. In both cases, it is ensured that the coolant is enriched with the salt.

[0067] The salt in the salt depot can be in solid form or dissolved in liquid form. The salt can be a salt from the group NaCl, KCl, or NFUCl, or contain at least one salt from the group NaCl, KCl, or NFUCl.

[0068] It is also proposed that the energy storage housing be perforated. Openings can be provided in the energy storage housing. The openings allow the coolant to flow directly around the battery cells. This leads to a better cooling effect. The exothermic reaction takes place within the battery cells. The goal is to bring the coolant as close as possible to the battery cells. The openings make this possible.

[0069] According to one aspect, it is proposed that the control device, when activated by the evaluation device, controls the connecting line in such a way that the protective container is flooded to at least 80%, preferably at least 90%, in particular between 95% and 100% of its free volume, after which the control device closes the connecting line. In this case, almost complete filling of the protective container is ensured, but at the same time, overflow of the protective container is prevented. It is also proposed that the quotient of the volume of the protective container and the storage capacity (energy content, maximum capacity) of the energy storage device (in kWh) be greater than 5 dm 3 per kWh, especially 7dm 3 / kWh. These values ​​are particularly relevant for cases where the protective container is flooded with coolant once. The volume of the coolant, especially water, can have a sufficient cooling effect at these values.

[0070] According to one aspect, it is proposed that the control device, when activated by the evaluation device, controls the connecting line depending on a maximum energy content or a maximum capacity of the energy storage device, wherein a limit value for the maximum energy is determined and above the limit value, the control device leaves the connecting line open after the protective container has been completely flooded. In this case, the drain nozzle is preferably also opened or remains open so that the coolant can drain away. This means that for energy storage devices up to a certain energy content, the protective container is only flooded until it is completely flooded, whereas for larger energy storage devices, flooding is continued and heated coolant is discharged via the drain nozzle.

[0071] It was found that a maximum cooling capacity is sufficient for conventional battery storage systems. In particular, it was found that when coolant is circulated, the cooling effect only increases up to a certain degree with increasing volume flow. Above a certain volume flow, the cooling performance on the battery is no longer significantly improved. It was found that this cooling performance is achieved at a volume flow of 20 l / min; above this, the additional cooling effect is no longer noticeably better. It is therefore proposed that the connecting line be connected to a water connection with a maximum volume flow of less than or equal to 20 l / min. Up to 20 l / min, the cooling performance increases at least linearly with increasing volume flow; above this, it was found that the improvement in cooling performance is less than linear.This may be different for energy storage systems with larger capacities, so a maximum flow rate of 25 l / min, 30 l / min, or more may be appropriate. It is also recommended that the connecting line have a symmetrical, hermaphrodite connection fitting. This can be a C-hose connection, in particular. These are widely available and can be connected even by a layperson with little experience.

[0072] It is also proposed that a coolant reservoir be located outside the protective container and fluidly connected to the connecting line. In addition to a water connection, it is also possible for the coolant to be supplied from a cylinder. Gas and water cylinders, especially cylinders, are well known in firefighting. These systems, either a pressurized water cylinder or a water cylinder and a compressed gas cylinder connected to drive the water from the water cylinder, are readily available and can be used to supply coolant, particularly in environments where no water connection is available.

[0073] A coolant supply can also include a pump. The pump can be motorized and / or manually operated, for example. The pump can pump coolant from a fluid volume toward a protective container, such as a tank. If the fluid is water, it is also possible to connect the pump to a fixed water supply for drinking or industrial water, to groundwater, or even to an open body of water.

[0074] In one embodiment, the protective device is arranged on a floating vehicle (ship, boat, platform). In this case, the pump can draw water directly from the body of water on which the floating vehicle is located. It is also possible for the fluid supply to be provided by the infrastructure on land. For example, the fluid supply could be a water connection to a building. This eliminates the need for an additional pump if the water pipe is already under sufficient pressure. This can be particularly useful for offshore applications. The protective container can be arranged in particular on an offshore energy installation, such as a substation, a wind turbine or the like.

[0075] It is also proposed that a cross-section of the connecting line be determined depending on a maximum energy content of the energy storage device or a maximum capacity of the energy storage device. It is also proposed that a channel cross-section of the drain channel be determined depending on a maximum energy content of the energy storage device or a maximum capacity of the energy storage device. It is also proposed that a channel cross-section of the drain nozzle be determined depending on a maximum energy content of the energy storage device or a maximum capacity of the energy storage device. It is also proposed that a cross-section of the connecting line be determined depending on a water pressure.It is also proposed that a line cross-section of the connecting line and / or a channel cross-section of the drain channel and / or a channel cross-section of the drain nozzle and / or a water pressure is determined as a function of a maximum energy content of the energy storage device or a maximum capacity of the energy storage device such that the heat capacity corresponding to the energy content is supplied by the coolant via the connecting line within a predetermined time. The time can be, for example, one minute, three minutes or five minutes, in particular between one and four minutes. The exhaust gas channel can be designed such that a specific gas volume can be discharged within the predetermined time, for example the above-mentioned gas volumes per kWh.

[0076] According to one embodiment, it is proposed that the channel cross-section of the exhaust gas duct is designed for a gas volume flow of up to 2501 / min. The channel cross-section of the exhaust gas duct is preferably determined as a function of the maximum storage capacity of the energy storage device. For large energy storage devices, the stated gas volume flow of 2501 / min may be too low. It is therefore also proposed that the channel cross-section of the exhaust gas duct is designed for a gas volume flow of more than 2001 / min, up to a maximum of 3001 / min or a maximum of 5001 / min or 8001 / min. In particular, the gas volume flow in the exhaust gas duct can be determined as a function of the maximum storage capacity of the energy storage device. For example, a quotient of gas volume flow and maximum storage capacity of the energy storage device can be between 51 / (kWh*min) and 101 / (kWh*min). For example, 251 / kWh within 5 minutes.The quotient of gas flow rate and the maximum storage capacity of the energy storage system may also be reasonable at 25 1 / (kWh*min). This gas flow rate may be particularly useful over a period of 5 minutes.

[0077] According to one embodiment, it is proposed that the duration of the opening of the connecting line by the control device is determined as a function of a maximum energy content of the energy storage device or a maximum capacity of the energy storage device. As already described above, it may be expedient to only flood the protective container and then cool the energy storage device with the available coolant. This can be the case, for example, with energy storage devices that have a maximum storage capacity of between 5 kWh and 10 kWh. For larger energy storage devices with storage capacities of over 5 kWh, it may be necessary to have coolant flow around the energy storage device at least for a time, so that after flooding, new coolant continues to be supplied via the connecting line and discharged via the drain ports. This flow of fresh coolant achieves an even better cooling effect.

[0078] According to one embodiment, it is proposed that a volume of the protective container is determined depending on a maximum energy content of the energy storage device or a maximum capacity of the energy storage device. The volume of the protective container also determines the volume of the coolant required for flooding or cooling. The volume of the coolant, in turn, is relevant for the cooling performance. If only flooding is used, a larger volume may be necessary to enable sufficient cooling. According to one embodiment, it is proposed that the exhaust duct has at least one flexible section outside the protective container. The flexible section can be used to adapt the connection of the exhaust duct to the installation situation of the protective container. For example, the exhaust duct can beIt can be routed to a wall duct and secured there, allowing the exhaust duct to be directly connected to the outside environment. This reduces installation effort.

[0079] According to one embodiment, it is proposed that the inner walls of the protective container have a maximum fire protection class of Al or A2 according to DIN 4102-2. Due to the flooding, a significant portion of the reaction energy of the exothermic reaction is already absorbed by the coolant. The inner walls of the protective container are only briefly exposed to the immediate reaction energy and can already be sufficiently dimensioned if it meets one of the aforementioned fire protection classes. It is also proposed that the inner walls of the protective container have a maximum fire protection class of A2-sl,d0 according to DIN EN 1350-1. It is also proposed that the inner walls of the protective container have a maximum fire protection class of B2 according to DIN 4102-1 or D according to EN 13501-1.

[0080] According to one embodiment, it is proposed that the inner walls of the protective container have a temperature resistance of a maximum of 200°C, preferably 150°C, in particular a maximum of 100°C. By flooding, coolant is brought directly to the reaction center. The coolant absorbs a large portion of the reaction energy. The coolant acts as a buffer between the inner walls of the protective container and the energy storage device. The reaction energy does not reach the inner walls directly, but is absorbed by the coolant. The coolant causes the inner walls to be exposed to temperatures of less than 200°C, preferably less than 100°C, throughout the entire reaction process. In the first few seconds of an exothermic reaction, the temperature on the inner walls may exceed these values.After flooding has begun, at the latest when the energy storage device is essentially surrounded by coolant, the coolant is present on the inner wall of the protective container and the temperature is below the specified values.

[0081] According to one embodiment, it is proposed that the inner walls of the protective container be non-flame-retardant. For the same reasons as with regard to temperature resistance, a non-flame-retardant design of the inner walls is also possible. Flames can only reach the inner wall at the beginning of the exothermic reaction. A non-flame-retardant design of the inner walls can be such that immediate exposure to a flame for less than 10 seconds or less than 5 seconds does not lead to spontaneous combustion.

[0082] According to one embodiment, it is proposed that at least a first and a second sensor are arranged in or on the protective container, the evaluation device activates a pre-alarm depending on at least a first sensor signal from the first sensor, and that the evaluation device activates an alarm depending on a second sensor signal from the second sensor that is different from the first sensor signal. The at least two sensors reduce the risk of false triggering of the flooding. If the protective container is flooded with coolant, in particular with water, total damage to the energy storage device can be assumed. Therefore, flooding without thermal runaway of the energy storage device must be prevented. If a first valve can already be actuated by a pre-alarm, the desired effect can be achieved more quickly in the event of an alarm. It is proposed that a valve on the connecting line is only opened in the event of an alarm.Another valve, e.g. a valve on the exhaust duct and / or a valve on the drain nozzle, can be opened when a pre-alarm is triggered. A valve on a ventilation opening can also be opened when a pre-alarm is triggered. After a pre-alarm, the state caused by the pre-alarm can be maintained for a period of 5 minutes, 10 minutes, 20 minutes, and even up to one hour. If no alarm is triggered during this time, the valves can be returned to their original state and the pre-alarm can be deactivated. If an alarm is triggered during this time, the valve on the connecting line can be opened and the protective container can be flooded. The other valves initially remain in the position caused by the pre-alarm.Essentially, in this context, "at the same time" can mean that the valves change their position within the time that is waited after a pre-alarm, whether an alarm is issued and then the valves return to their initial state.

[0083] According to one embodiment, it is proposed that the control device opens the exhaust duct in the event of a pre-alarm and / or closes a valve at the air supply opening and a valve at the exhaust opening. Opening the exhaust duct ensures that, in the event of an alarm, smoke gas can be immediately discharged via the exhaust duct. In the event of an explosion of the energy storage device, a significant volume of gases is released in a very short time. To prevent undesirable overpressure from building up within the protective container, the vent opening is opened early.

[0084] According to one embodiment, it is proposed that the control device opens the connecting line in the event of an alarm and / or closes a valve at the supply air opening and a valve at the exhaust air opening.

[0085] The combination of receiving sensor data and controlling actuators can enable effective combatting of dangerous operating conditions as well as one or more warnings and / or other automated measures. As already mentioned, data from a BMS can also be used to detect dangerous (critical) operating conditions. In particular, flooding of the protective vessel can be triggered via the connecting line if a condition classified as critical has been reached. Continuous monitoring of the protective vessel, particularly of gases, can ensure timely triggering and monitor the success of the measures. For example, a temperature can be continuously measured and an inflow and outflow can be maintained until a target temperature is reached.

[0086] Flooding the volume of the protective container offers the advantage of ensuring direct cooling of the energy storage device by means of the coolant directly surrounding it. Since the coolant can evaporate, for example, by releasing steam via a suitable exhaust duct, a maximum temperature of approximately 100 °C on the energy storage device's surface is ensured.

[0087] Another embodiment relates to a vehicle in which a specific protective device is arranged. In particular, this can be a watercraft. In this case, the protective container can, for example, be formed at least partially by an existing part of the watercraft, such as a storage compartment. It is advantageous here that the fluid supply can be implemented as a water supply directly via a pump, which can pump the water on which the watercraft floats into the protective container. A water pump is often already present on board anyway.

[0088] A further embodiment relates to a building in which a protective device in question is arranged.

[0089] In one embodiment, the protective device can be movable, in particular movable as a whole, in particular portable. For example, the device can be subsequently installed in buildings and / or vehicles. It is also possible to later remove the protective device from a building and / or vehicle. In particular, in the event of a fire, the protective device can be removed from a hazardous environment such as a building and / or a vehicle. For example, the protective device can be dropped overboard from a vehicle, in particular a watercraft. The subject matter is explained in more detail below with reference to a drawing showing exemplary embodiments. In the drawing:

[0090] Fig. 1 A protective device according to an embodiment;

[0091] Fig. 1 shows a protective device in question.

[0092] A room 100 is shown. The room 100 can be, for example, a basement, a garage, or another part of a building. An energy storage device 102 can be located within the room 100. The energy storage device 102 can be, for example, a storage battery of a house's photovoltaic system. The energy storage device 102 can have a plurality of battery modules made up of battery cells. The energy storage device 102 can have a battery management system (BMS) 102a. The battery management system 102a controls the charging and discharging of the battery cells.

[0093] The energy storage device can have an energy storage housing 104. An energy storage housing 104 can house the battery modules and battery cells of the energy storage device 102. A single energy storage device 102 with an energy storage housing 104 is shown, but more than one energy storage device 102 is also possible within the scope of the present solution.

[0094] The energy storage housing 104 is physically housed in a protective container 106. The protective container 106 completely encloses the energy storage device 102 and its energy storage housing 106. The protective container 106 can be completely closed.

[0095] A connecting line 108 is connected to the protective container 106. The connecting line 108 is connected to the interior of the protective container 106 via a valve 108a. The connecting line is connected to a water connection 110. The valve 108a is signal-connected to a control device 112.

[0096] The control device 112 is connected to at least one, preferably more than one, sensor 114. The sensor 114 can also be part of the BMS 102a. The control device 112 can also be connected to the BMS 102a. The sensors 114 can be arranged on or in the protective container 106. The sensors 114 can be arranged on or in the energy storage housing 104.

[0097] The sensors 114 are configured to detect a thermal runaway, possibly one that is just about to occur, of the energy storage device 102. In particular, one sensor 114 can be a gas sensor that can measure a concentration of venting gases. A second sensor 114 can be configured to detect a fire or explosion of the energy storage device 102, e.g., in the form of a temperature sensor.

[0098] The control device 112 is signal-connected to the valve 108a and a valve 116a of an exhaust duct 116. The exhaust duct 116 is connected to the interior of the protective container 106. The exhaust duct 106 leads out of the chamber 100 via the valve 116a. The exhaust duct 116 can be routed through a wall of the chamber 100 and lead to the outside.

[0099] In addition, a ventilation opening 118 may be provided on the protective container 106. A valve at the ventilation opening 118 may also be signal-connected to the control device 112.

[0100] During normal operation, the energy storage device 102 charges and discharges depending on a load or a generator within a distribution network to which the energy storage device 102 is connected.

[0101] In this normal operation, valves 108a and 116a are closed, and the valve at ventilation opening 118 is open. Sensors 114 continuously monitor the measurement parameters and report them to control device 112. In control device 112, the measured values ​​of sensors 114 are evaluated by an evaluation device (not shown). It should be noted that control device 112, the evaluation device, and, if applicable, BMS 102a can be integrated into a single device.

[0102] It may happen that, for example, a first sensor 114 detects an elevated measured value, e.g., a temperature, venting gases, or the like. The evaluation device compares the detected measured values ​​with a limit value. If this limit is exceeded, it can be concluded, for example, that thermal runaway is imminent. If, for example, venting gases are detected, then thermal runaway has already occurred.

[0103] The evaluation device can then issue a pre-alarm.

[0104] Due to a pre-alarm, the control device 112 can, for example, open the valve 116a and close the valve at the ventilation openings 118.

[0105] The pre-alarm now remains active for a predetermined time, e.g., 5 minutes. The pre-alarm can also remain active for a longer time, e.g., 15 minutes, 60 minutes, 120 minutes, or more. If another measured value from another sensor 114 rises above a limit within this predetermined time, an alarm can be triggered. Based on the alarm, valve 108a is then also opened, and the protective container 106 is flooded with water.

[0106] The triggering of the alarm within the time period following a pre-alarm can be understood as essentially simultaneous.

[0107] If, within the time following the pre-alarm, the measured value of the sensor(s) that triggered the pre-alarm, e.g. temperature, venting gases or the like, falls below a limit value and / or no further measured value of another sensor exceeds a limit value, the pre-alarm can be terminated and the device can return to its normal state.

[0108] After the valve 108a is opened, water flows into the protective container 106 and flows around the energy storage housing 104. The water cools the energy storage housing 106. Explosion and fire gases that could be generated by thermal runaway are transported to the atmosphere via the exhaust duct 106.

Claims

Patent claims 1. A protective device for an energy storage device comprising a protective container enclosing the energy storage device, at least one connecting line for a coolant leading into the protective container and at least one exhaust gas duct leading out of the protective container, characterized in that, depending on at least one measured value, in particular a sensor measured value and / or data from a battery management system, a valve on the connecting line moves essentially simultaneously from a first position to a second position and at least one of a valve on the exhaust gas duct and / or a valve on at least one ventilation opening of the protective container moves from a first position to a second position.

2. Protective device according to claim 1, characterized in that at least one sensor is arranged within the protective container, wherein the at least one sensor is configured to detect at least the temperature and / or the gas concentration, in particular a gas concentration of venting gases of the battery cells and / or the smoke within the protective container.

3. Protection device according to claim 2, characterized in that an evaluation device is coupled to the sensor and that the evaluation device detects a malfunction of the energy storage device depending on at least one sensor signal and / or that the evaluation device is coupled to a battery management system and the evaluation device detects a malfunction of the energy storage device depending on operating data of the battery management system.

4. Protection device according to claim 3, characterized in that a control device is controlled by the evaluation device in the event of a detected malfunction, wherein the control device changes the valve position of the valves when controlled by the evaluation device.

5. Protection device according to one of the preceding claims, characterized in that the evaluation device and / or the control device is part of a battery management system of the battery and / or that at least one of the valves is controlled by a battery management system of the battery.

6. Protective device according to one of the preceding claims, characterized in that at least one of the valves is a thermally activated valve, in particular via a bimetallic part, which moves the valve from the first position to the second position depending on a temperature in the protective container.

7. Protective device according to one of the preceding claims, characterized in that that in the event of a detected malfunction, the control device controls, in particular opens, at least one switch on one of the connections arranged on the outer wall of an energy storage housing.

8. Protection device according to one of the preceding claims, characterized in that at least one salt depot, in particular a NaCl depot, is arranged in the protective container and / or in the connecting line, and that salt from the salt depot is dissolved in the coolant flooding the protective container.

9. Protection device according to one of the preceding claims, characterized in that the salt depot is passive, such that coolant flowing on or through the salt depot dissolves the salt from the salt depot, or that the salt depot is active and that the control device controls the salt depot, such that salt is released from the salt depot into the coolant.

10. Protection device according to claim 8 or 9, characterized in that the salt in the salt depot is solid or dissolved and / or that the salt in the salt depot is one from the group NaCl, KCl, NEUCl or contains at least one from the group NaCl, KCl, NEUCl.

11. Protective device according to one of the preceding claims, characterized in that the control device, when controlled by the evaluation device, controls the valve on the connecting line in such a way that the protective container is flooded to at least 80%, preferably at least 90%, in particular between 95% and 100% of its free volume and then the control device closes the valve on the connecting line.

12. Protective device according to one of the preceding claims, characterized in that the control device, when controlled by the evaluation device, controls a valve on the connecting line depending on a maximum energy content or a maximum capacity of the energy storage device, wherein a limit value of the maximum energy is determined and above the limit value the control device leaves a valve on the connecting line open after complete flooding of the protective container.

13. Protection device according to one of the preceding claims, characterized in that the connecting line is connected to a water connection with a maximum volume flow of less than or equal to 20 l / min and the control device controls a valve in the connecting line.

14. Protection device according to one of the preceding claims, characterized in that the connecting line is connected to a drinking water connection, in particular that the connecting line is connected to a domestic water connection.

15. Protection device according to one of the preceding claims, characterized in that the connecting line has a symmetrical, hermaphrodite connection fitting.

16. Protection device according to one of the preceding claims, characterized in that a coolant container is arranged outside the protective container and is fluidly connected to the connecting line.

17. Protection device according to one of the preceding claims, characterized in that a line cross-section of the connecting line and / or a channel cross-section of the exhaust gas channel is determined depending on a maximum energy content of the energy storage device or a maximum capacity of the energy storage device.

18. Protection device according to one of the preceding claims, characterized in that the channel cross-section of the exhaust gas channel is designed for a gas volume flow of up to 5001 / min.

19. Protection device according to one of the preceding claims, characterized in that a duration of the opening of a valve on the connecting line is determined by the control device as a function of a maximum energy content of the energy storage device or a maximum capacity of the energy storage device.

20. Protective device according to one of the preceding claims, characterized in that a volume of the protective container is determined as a function of a maximum energy content of the energy storage device or a maximum capacity of the energy storage device.

21. Protective device according to one of the preceding claims, characterized in that the exhaust gas duct has at least one flexible section outside the protective container.

22. Protective device according to one of the preceding claims, characterized in that the inner walls of the protective container have a maximum fire protection class Al and A2 according to DIN 4102-2 or A2-sl,d0 according to DIN EN 1350-1.

23. Protective device according to one of the preceding claims, characterized in that the inner walls of the protective container have a temperature resistance of maximum 200°C, preferably 150°C, in particular maximum 100°C.

24. Protective device according to one of the preceding claims, characterized in that the inner walls of the protective container are not flame-retardant.

25. Protective device according to one of the preceding claims, characterized in that an energy storage housing for the energy storage device is housed in the protective housing and / or that the energy storage housing is perforated.

26. Protective device according to one of the preceding claims, characterized in that at least a first and a second sensor are arranged in or on the protective container, that the evaluation device activates a pre-alarm depending on at least a first sensor signal of the first sensor and that the evaluation device activates an alarm depending on a second sensor signal of the second sensor which is different from the first sensor signal. TI . Protective device according to one of the preceding claims, characterized in that that in the event of a pre-alarm, the control device opens a valve on the exhaust duct and / or closes a valve on the supply air opening and a valve on the exhaust air opening.

28. Protective device according to one of the preceding claims, characterized in that the control device opens a valve on the connecting line and / or closes a valve on the supply air opening and a valve on the exhaust air opening in the event of an alarm.

29. Method for operating a protective device for an energy storage device according to claim 1, in which, depending on at least one temperature and / or a gas concentration, in particular a gas concentration of venting gases of the battery cells and / or smoke within the protective container, a valve on the connecting line is moved substantially simultaneously from a first position to a second position and at least one of a valve on the exhaust duct and / or a valve on at least one ventilation opening of the protective container is moved from a first position to a second position.

Images