DE102013014903A1 - Battery with means for removing leaked coolant from the inside of the battery case - Google Patents

Abstract

The present invention relates to a battery comprising a battery case (1) and a single battery cell (2) arranged in the battery case or an assembly of a plurality of battery cells (2), wherein the battery cell (2) or the assembly of a plurality of batteries Single cells (2) can be tempered by a cooling device, in which a liquid coolant flows through a coolant circuit, wherein a liquid coolant can be flowed through by the cooling means (3) of the cooling device for transferring heat from the battery single cell (2) or the arrangement of a plurality of battery-individual cells (2) to the liquid coolant inside the battery case (1) is arranged, wherein the wall of the battery case (1) has a valve (5, 5 '), a predetermined breaking point and / or a breakdown point, the within the wall of the battery case (1) is / are arranged such that in the event of leakage of liquid coolant from d he cooling device inside the battery case (1), this liquid coolant through the valve (5, 5 '), the predetermined breaking point and / or the breakdown point to the outside of the battery case (1) can be discharged.

Description

The present invention relates to a battery having means for removing leaked coolant from inside the battery case.

As a traction storage or energy storage of modern electric vehicles or electric motor driven vehicles (eg hybrid vehicles) currently mainly rechargeable lithium batteries (lithium-ion batteries, lithium-ion polymer batteries) are used due to their relatively high energy and power density , To a lesser extent, other rechargeable battery types are used, such as rechargeable nickel-metal hydride batteries.

In these traction accumulators, rechargeable battery cells are connected in series in order to obtain the required for the traction of an electric motor driven vehicle electrical voltage. Several of the individual battery cells thus obtained can also be connected in parallel with one another in order to ensure a sufficient current intensity. The batteries thus obtained are often referred to as high-voltage batteries (HV batteries).

Rechargeable lithium batteries are characterized in the current state of the art in that their life or their performance (ie, the decline in their performance and capacity) depends essentially on the temperatures at which these batteries are operated, or by the temperatures, which they are exposed during their lifetime. But even with other types of batteries, such as the acid-lead battery or the nickel-metal hydride battery life expectancy decreases when they are operated at higher temperatures or are exposed to higher temperatures.

Against this background, a number of technical solutions for cooling or tempering batteries have been developed. A principle often used here comprises a cooling device which comprises a cooling device through which a liquid, water-containing coolant flows, which is arranged inside the battery housing and here as close as possible to the battery individual cells.

Corresponding cooling devices have the disadvantage that in the event of a leakage inside the battery housing (for example, if the cooling device is damaged and / or the supply lines for the coolant after an accident) an uncontrolled full running of the battery housing with coolant occurs or can occur. The same applies to submersible batteries according to IP69 or IP67 due to openings that are not closed in normal operating condition.

The amount of running in the battery case coolant (cooling water) can in this case be almost the entire amount of coolant in the worst case, which may have a volume of up to several liters. This can lead to internal short circuits or destruction / damage of battery cells.

Internal short circuits can cause rapid local overheating of the battery cells. To prevent excessive pressure rise inside the battery case, it is known to provide predetermined breaking points or pressure relief valves. In order to prevent an uncontrolled leakage of often corrosive electrolytes from the battery case in an internal short circuit, and safety devices are known, as for example in the DE 38 26 423 C1 are described.

According to this document, at least one drain valve is provided in the battery cell and a removal means, preferably in the form of an inert gas stored under pressure in a container, is provided, which is rapidly fed into the coolant line via a conduit and pushes out the remaining coolant, so that it is not emptied into the battery.

However, the penetration of water-containing coolant into the interior of the battery case can not only cause short circuits, but due to the many electrochemical cells and the associated electrical voltage differences, the risk of electrolysis of water to form explosive detonating gas.

Although it would be possible to provide for circumvention of these disadvantages isolation of the electrical system to liquids; However, this is very expensive in practice and even minimal isolation gaps can lead to failure.

Against this background, it is an object of the present invention to provide an advantageous battery in which liquid coolant, which has penetrated into the interior of a battery case due to leakage, can be removed quickly and safely. This object is achieved by the battery according to claim 1. Advantageous developments of the invention are the subject of the dependent claims.

According to the invention, a battery is provided with a battery housing and a battery cell arranged in the battery housing or proposed an arrangement of a plurality of battery-single cells, wherein the battery-single cell or the arrangement of a plurality of battery-individual cells is tempered by a cooling device in which a liquid coolant flows through a coolant circuit, wherein a flow-through of the liquid coolant cooling means of the cooling device for transmission of heat from the battery single cell or the arrangement of a plurality of battery single cells is arranged to the liquid coolant inside the battery case.

The battery according to the invention is characterized in that the wall of the battery housing has a valve, a predetermined breaking point and / or a break-through point which is / are arranged within the wall of the battery housing such that in the event of leakage of liquid coolant from the cooling device inside the Battery housing, this liquid coolant through the valve, the predetermined breaking point and / or the breakdown point can be discharged to the outside of the battery case.

By means of the battery according to the invention, short circuits due to leaking coolant and the associated further dangers and disadvantages can be reliably prevented.

According to a first advantageous embodiment of the invention, the battery is characterized in that one of the valve, the predetermined breaking point or the break-through point is arranged at the bottom of the battery housing in an installed state of the battery.

According to a second advantageous embodiment of the invention, the battery is characterized in that a plurality of valves, predetermined breaking points and / or breakthrough points are provided, which are arranged on at least two different sides of the battery case, which are selectable from side wall / side walls, bottom and top.

According to a third advantageous embodiment of the invention, the battery is characterized in that further at least one moisture sensor in the interior and / or below the battery case, at least one level sensor for the liquid coolant and / or at least one acceleration sensor are provided, wherein the at least one valve in dependence is controllable by at least one signal of the / sensors / sensors.

According to a further advantageous embodiment of the invention, the battery is characterized in that at least one check valve is provided within the coolant circuit, by the subsequent flow and / or backflow of liquid coolant into the interior of the battery case in the event of leakage of liquid coolant from the cooling device in Inside the battery case can be prevented or reduced.

Advantageously, in the battery according to the invention a device for removing liquid coolant from at least the part of the cooling device is provided, which is located inside the battery case, wherein the device comprises a drain valve for the liquid refrigerant in a drain line and a shut-off valve for preventing the afterflow of liquid coolant in the part of the cooling device, which is located inside the battery case.

If a device for removing liquid coolant is provided in the battery according to the invention, advantageously a gas generator device, an accumulator device or a vacuum device can be provided, which can be brought into fluid communication with the coolant circuit and by means of the liquid coolant by positive or negative pressure from at least the part of the cooling device, which is located inside the battery case, can be pushed out or sucked.

If at least one valve of the battery is in response to at least one signal of a sensor associated with the battery (eg a humidity sensor inside and / or below the battery housing, a liquid coolant level sensor, an acceleration sensor on or in the battery housing) and / or or a signal of a peripheral sensor, for example the sensor associated with the vehicle (eg an airbag acceleration sensor), the at least one valve can be opened after evaluation of the signal (s) of the sensor (s) and thus also a proactive one Emptying of the coolant circuit are performed.

The present invention will be explained in more detail with reference to the accompanying drawings.

In each case show purely schematic and not to scale:

1 a first embodiment of the battery according to the invention;

2 a second embodiment of the battery according to the invention;

3 a third embodiment of the battery according to the invention;

4 A fourth embodiment of the battery according to the invention.

The embodiments described in more detail below represent preferred embodiments of the present invention. The present invention is of course not limited to these embodiments.

To avoid internal battery short circuits or destruction of the battery cells by liquid coolant (leakage water) from the battery cooling circuit, z. B. after line damage or deformation in the battery interior after crash events, an immediate discharge or anticipatory emptying of the liquid coolant (cooling water) is carried out from the cooling circuit.

As in 1 is shown, the battery according to the invention to solve this problem in its simplest embodiment, a battery case 1 and a battery cell disposed in the battery case 2 or an array of multiple battery cells 2 (Cell block) on, with the battery single cell 2 or the arrangement of several battery-single cells 2 is temperature controlled by a cooling device in which a liquid coolant flows through a coolant circuit.

A cooling device through which the liquid coolant can flow 3 the cooling device for transferring heat from the battery single cell 2 or the arrangement of a plurality of battery single cells 2 to the liquid coolant is inside the battery case 1 arranged. By way of example, this cooling device may be one or more cooling plates adjacent to one side of the single battery cell 2 or the arrangement of a plurality of battery single cells 2 is / are arranged. By the cooling device 3 can coolant through the coolant connections (pipes, pipes) 4 and 4 ' be added and removed.

The wall of the battery case 1 has a valve 5 , a predetermined breaking point and / or a breakthrough point (the latter are not shown in the figures), which are so within the wall of the battery case 1 is arranged / are that in case of leakage of liquid coolant from the cooling device inside the battery case 1 (eg from the cooling device 3 or one of the lines 4 . 4 ' ), this liquid coolant through the valve 5 , the predetermined breaking point and / or the breakdown point to the outside of the battery case 1 can be discharged.

The emptying of the leakage water from the battery can by means of a manually or automatically (active) controlled valve 5 or a predetermined breaking point (this is triggered in a crash, for example, by deformation or by acting on a thin membrane inertial mass) or a breakthrough site.

One of the valve (s) 5 , the predetermined breaking point (s) or the break-through point (s) are advantageously located at the location of the battery closest to the bottom of the battery housing 1 or the circuit arranged.

The drainage function can be carried out according to battery-external areas (eg collecting trough on the vehicle or outdoors).

At the in 1 illustrated embodiment is the valve 5 a manually operable, by an actuation of an actuating element 10 can be opened and closed. This is a feasible manual triggering the emptying of the battery case 1 is for example advantageous for ensuring the recovery of an accident vehicle.

If a rotation of the battery about its axes during operation is possible (eg in the case of a rollover of a vehicle), advantageously several valves, predetermined breaking points and / or breakthrough points can be provided, which are arranged on at least two different sides of the battery housing, which are selectable from side wall / side walls, bottom and top.

It can also valves 5 . 5 ' , Predetermined breaking points and / or breakthrough points in conjunction with all possible battery space layers may be provided so that in any case an emptying of the interior of the battery case 1 Of leaked liquid coolant is possible. An example of a multi-valve battery according to the invention 5 . 5 ' is in the 2 and 3 shown schematically.

To have an automatic active and / or pro-active emptying of the inside of the battery case 1 to allow, as in 2 is shown schematically - in an advantageous manner in the battery according to the invention further at least one humidity sensor 7 . 7 ' in the interior and / or below the battery housing, at least one (not shown in the figures) level sensor for the liquid coolant and / or at least one acceleration sensor 6 be provided, wherein the at least one valve 5 . 5 ' as a function of at least one signal of the / sensors / sensors can be controlled. The signals of the humidity sensor (s), the level sensor (s), and / or the acceleration sensor (s) may be, for example by means of signal lines 8th . 8th' . 8th'' to the valve 5 . 5 ' be transmitted.

The acceleration sensor 6 does not have to be in the area of the battery or the battery case 1 be arranged. It can according to the invention for driving the at least one valve 5 . 5 ' also the signal of a crash sensor of the vehicle (eg signal of deployment of the airbag) are used. The control of the at least one valve 5 . 5 ' via the acceleration sensor 6 is dependent on an external event, such. B. a crash.

The humidity sensor (s) 7 . 7 ' is / are advantageously in the interior of the battery case 1 arranged, whereby he / she the interior of the battery case 1 to monitor for fluid. Regarding the arrangement of the humidity sensor (s) 7 . 7 ' inside the battery case 1 the same applies above with respect to the valve (s) 5 . 5 ' , the predetermined breaking point (s) and the breakdown point (s) was executed. As a result, leaks of the cooling device, as far as they are in the interior of the battery case 1 occur (cooling device 3 and wires 4 . 4 ' ) is detected via the occurrence and / or height of a given liquid level.

The level sensor (s) may for example be arranged in a surge tank of the circuit. In this case, the sensor signal would be triggered by a leak detected by a sinking level in the expansion tank. However, a fill level sensor can also be made passive mechanically, for example in the form of a valve 5 . 5 ' connected float, at a suitable location inside the battery case 1 is arranged. A leakage of cooling water inside the battery case 1 causes an increase in the level of liquid within the battery, which raises the float, which in turn causes the valve 5 . 5 ' is opened (reactive).

But it can also be an emptying of the circuit already in the presence of a signal from at least one of the sensors, without checking whether there is really a damage to the circuit (pro-active).

As in 3 is shown schematically, can / can in the battery according to the invention at least one check valve 9 . 9 ' be provided within the coolant circuit, by the / a subsequent flow and / or backflow of liquid coolant into the interior of the battery case 1 in the event of leakage of liquid coolant from the cooling device inside the battery case 1 can be prevented or reduced.

Check valve (s) 9 . 9 ' can at the coolant outlet 4 ' and / or between one or more cooling plates of the cooling device 3 be provided. This is possible because, as standard, the coolant flow only runs in one direction (inlet / outlet is not changed).

According to another, in 4 schematically illustrated advantageous development can be provided in the battery of the invention, a device for removing liquid coolant from at least the part of the cooling device, which is located in the interior of the battery case 1 is located, wherein the device is a drain valve 11 for the liquid coolant in a drain line 13 and a shut-off valve 12 for preventing the flow of liquid coolant into the part of the cooling device located in the interior of the battery housing 1 located.

Through this development, a passive or active emptying of coolant from the cooling device can be achieved. When the shut-off valve 12 closed and the drain valve 11 be opened, there is a passive emptying of coolant, ie the coolant runs alone due to gravity and / or the operating pressure through the drain line 13 out.

The device for removing coolant may further comprise a gas generator device 14 (analogous operation such as airbag), a pressure storage device 14 or a vacuum device 14 having, by means of a pressure line 15 can be brought into fluid communication with the coolant circuit and by means of the liquid coolant by generating over or under pressure from at least the part of the cooling device, which is located inside the battery case, pushed out (blown) or can be sucked off. Also, such an active emptying course, regardless of location feasible.

The control of the valves 11 . 12 usually takes place via pressurized (hydraulic, pneumatic) or electrical signal lines 8th''' . 8th'''' , which are in communication with the gas generator device 14 , Pressure accumulator device 14 or vacuum device 14 ,

As a supplement or alternative to the previously described embodiments, a bypass of the coolant flow, not shown in the figures, can be provided according to the invention, so that in the event of leakage inside the battery housing 1 no additional coolant in the interior of the battery case 1 can run after, the remaining coolant circuit, however, remains intact.

The present invention also provides protection of the refrigeration cycle from freezing coolant (eg, in the case of incorrectly refilled refrigerant, water rather than water / glycol). By means of a predetermined breaking point (eg material weakening, such as a membrane) or by another material (eg glass) which breaks in freezing water and allows the water to escape (at least after thawing). It should be noted here a pressure-resistant design of the rest of the system.

In order to avoid damage to the battery caused by escaping coolant due to excessive operating pressure, the use of a predetermined breaking point is possible or a pressure relief valve, which performs a drain function. As a result, the coolant is discharged at a defined location, whereby the "flooding" of the battery is prevented by escaping coolant.

The term "battery" used in the present application encompasses all types of batteries (electrochemical energy stores), ie rechargeable and non-rechargeable batteries, and includes batteries with one or more individual battery cells, wherein one or more cell blocks may be present, each consisting of a plurality of single battery cells are formed. Also, the term "battery" includes all electrochemical energy storage devices regardless of the technology / technology used therein.

The technical teaching disclosed in this application is also applicable to other in an enclosure energy converter, such as. Fuel cells, correspondingly applicable, d. H. the exiting in a housing interior cooling water is discharged with / by the means described above / method or its entry into the housing interior is avoided.

• – Sichere Entleerung des Kühlkreislaufs durch die Batterie mittels Ventil(en), Sollbruchstelle(n) und/oder Durchbruchstelle(n);
• – Verhinderung von Kurzschlüssen durch auslaufendes flüssiges Kühlmittel;
• – Möglichkeit der Kopplung des Signals zur Ventilsteuerung mit einem Crash-Signal (analog Airbag) oder Feuchtigkeitssensor-/Flüssigkeitssensor-Signal zur zeitnahen Öffnung des/der Ventile;
• – Möglichkeit des Einbaus von Rückschlagventilen innerhalb des Batteriesystems, um Nachströmen/Rückströmen von Kühlmittel zu vermeiden;
• – Möglichkeit einer aktiven Kühlkreisentleerung mittels Zuschaltung z. B. einer Druckspeichereinrichtung, einer Gasgeneratoreinrichtung oder eine Unterdruckeinrichtung;
• – Möglichkeit des Einsatzes von mehreren Entleerungsventilen, Sollbruchstellen und/oder Durchbruchstellen, um ein sicheres Entleeren von Leckage-Wasser unabhängig von der Batterie-Endlage zu ermöglichen;
• – Möglichkeit des Vorsehens eines Überdruckventils/einer Sollbruchstelle im Kreislauf, die bei Frost etc. (z. B. wenn Kühlplatten der Kühleinrichtung geborsten sind) Entleerung einleiten oder auch Kühlmittel-Überdruck vor einer Beschädigung des Kühlsystems der Batterie ableiten;
• – Möglichkeit einer manuellen oder automatischen Betätigung des/der Ablassventils/Ablassventile (Entleerungsventils/Entleerungsventile) nach einem Ereignis;
• – Durchführung einer pro-aktiven Kühlkreisentleerung bzw. Absperrung, d. h. vor dem eigentlichen Eintritt des Ereignisses durch Auswerten entsprechender Warnsensorik (ähnlich dem Pre-Safe System).

The present invention offers the following advantages and benefits in particular:

• - Safe drainage of the cooling circuit by the battery by means of valve (s), predetermined breaking point (s) and / or breakthrough point (s);
• - Prevention of short circuits due to leaking liquid coolant;
• - Possibility of coupling the signal to the valve control with a crash signal (analog airbag) or moisture sensor / liquid sensor signal for timely opening of the / the valves;
• Possibility of incorporating check valves within the battery system to prevent backflow / backflow of coolant;
• - Possibility of active Kühlkreisentleerung by switching z. B. a pressure storage device, a gas generator device or a vacuum device;
• - Possibility of using multiple drain valves, break points and / or breakthrough points to allow safe drainage of leakage water regardless of the battery end position;
• - Possibility of providing a pressure relief valve / a predetermined breaking point in the circuit, which in case of frost, etc. (eg., If cooling plates of the cooling device have burst) initiate emptying or even coolant overpressure prevent damage to the cooling system of the battery;
• Possibility of manual or automatic actuation of the drain valve / drain valves (drain valves / drain valves) after an event;
• - Carrying out a proactive cooling circuit drainage or shut-off, ie before the actual occurrence of the event by evaluating corresponding warning sensors (similar to the Pre-Safe System).

LIST OF REFERENCE NUMBERS

1

battery case

2

Single cell battery or cell block

3

cooling element

4, 4 '

Coolant connection

5, 5 ', 5' '

drain valve

6

crash sensor

7, 7 '

humidity sensor

8, 8 ', 8' ', 8' '', 8 '' ''

signal line

9, 9 '

check valve

10

actuator

11

drain valve

12

shut-off valve

13

drain line

14

Gas generator device, pressure storage device or vacuum device

15

pressure line

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3826423 C1 [0008]

Claims (8)

Battery with a battery case ( 1 ) and a battery cell arranged in the battery housing ( 2 ) or an arrangement of several individual battery cells ( 2 ), whereby the battery single cell ( 2 ) or the arrangement of several battery cells ( 2 ) is tempered by a cooling device in which a liquid coolant flows through a coolant circuit, wherein a cooling device through which the liquid coolant can flow ( 3 ) of the cooling device for transferring heat from the battery single cell ( 2 ) or the arrangement of several battery cells ( 2 ) to the liquid coolant inside the battery case ( 1 ), characterized in that the wall of the battery housing ( 1 ) a valve ( 5 . 5 ' ), a predetermined breaking point and / or a break-through point, which in such a way within the wall of the battery case ( 1 ) is arranged such that in case of leakage of liquid coolant from the cooling device inside the battery case ( 1 ), this liquid coolant through the valve ( 5 . 5 ' ), the predetermined breaking point and / or the breakdown point to the outside of the battery housing ( 1 ) can be discharged. Battery according to claim 1, characterized in that one of the valve ( 5 . 5 ' ), the predetermined breaking point or the breakdown point at the bottom of a battery in a state of installation of the battery housing ( 1 ) is arranged. Battery according to claim 1 or 2, characterized in that a plurality of valves ( 5 . 5 ' ), Predetermined breaking points and / or breakthrough points are provided on at least two different sides of the battery case ( 1 ) are arranged, which are selectable from side wall / side walls, bottom and top. Battery according to one of the preceding claims, characterized in that further at least one humidity sensor ( 7 . 7 ' ) inside and / or below the battery case ( 1 ), at least one level sensor for the liquid coolant and / or at least one acceleration sensor ( 6 ) is / are provided, wherein the at least one valve ( 5 . 5 ' ) in response to at least one signal from the sensor (s) ( 6 . 7 . 7 ' ) is controllable. Battery according to one of the preceding claims, characterized in that at least one check valve ( 9 . 9 ' ) is provided within the coolant circuit, by the subsequent flow and / or backflow of liquid coolant into the interior of the battery case ( 1 ) in the event of leakage of liquid coolant from the cooling device inside the battery case ( 1 ) can be prevented or reduced. Battery according to one of the preceding claims, characterized in that a device for removing coolant from at least the part of the cooling device is provided, which is located inside the battery case ( 1 ), the device having a drain valve ( 11 ) for the liquid coolant in a drain line ( 13 ) and a shut-off valve ( 12 ) for preventing the flow of liquid coolant into the part of the cooling device which is located inside the battery housing ( 1 ) is located. Battery according to claim 6, characterized in that further comprises a gas generator device ( 14 ), an accumulator device ( 14 ) or a vacuum device ( 14 ) is provided, which can be brought into fluid communication with the coolant circuit and by means of the liquid coolant by positive or negative pressure from at least the part of the cooling device, which is inside the battery case ( 1 ), can be pushed out or sucked off. Battery according to claim 4, characterized in that a pro-active emptying of the coolant circuit is feasible by the at least one valve ( 5 . 5 ' ) is opened after evaluation of the signal / signals of a sensor associated with the battery and / or a peripheral sensor.

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