WO2010040363A2

WO2010040363A2 - Lithium ion battery

Info

Publication number: WO2010040363A2
Application number: PCT/EP2008/008459
Authority: WO
Inventors: Hans Kemper; Thomas HÜLSHORST
Original assignee: Fev Motorentechnik Gmbh
Priority date: 2008-10-07
Filing date: 2008-10-07
Publication date: 2010-04-15
Also published as: WO2010040363A3; WO2010040520A3; WO2010040520A2; DE112009002264T5; DE112008004016A5

Abstract

The invention relates to a vehicle battery (3), for an electric or hybrid vehicle (1), wherein the battery (3) comprises several lithium ion cells (4), arranged together discretely in an outer housing (7) which is placed in a vehicle (1) in an exchangeable manner. A self-securing modular construction of lithium polymer cells is preferably used.

Description

Lithium Ion Battery

The present invention relates to a motor vehicle battery, in particular for a hybrid or electric motor vehicle, wherein the battery comprises a plurality of lithium-ion cells.

WO 2008/083920 discloses an electrochemical cell which forms a battery for use in a vehicle with a large number of other cells as so-called "coffee bag cells". From this document, the basic structure of such a cell system is apparent.

Object of the present invention is to provide a motor vehicle battery that is particularly accident-proof.

This object is achieved with a motor vehicle battery having the features of claim 1, with an arrangement of a motor vehicle battery having the features of claim 23, a use of coffee bag cells with the features of claim 26 and with a method having the features of claim 27 , Further advantageous embodiments can be taken from the respective subclaims. However, the resulting from the respective subclaims individual features are not limited to the embodiments of the individual subclaims. Rather, these individual features can be linked to other features from other subclaims as well as from the description to developments.

It is proposed to provide a motor vehicle battery for a hybrid or an electric motor vehicle, wherein the battery comprises a plurality of lithium-ion cells, which are arranged separably connected to each other in an outer housing, which is used interchangeably in a motor vehicle. Because the lithium-ion cells can be separated from one another, the motor vehicle battery can be adapted to the respective intended use and, in particular, also allow interchangeability of one or more lithium-ion cells without the entire motor vehicle battery being replaced must become. The fact that the motor vehicle battery itself is also used interchangeably in the motor vehicle, results in a particularly advantageous possibility to be able to perform the replacement of one or more lithium-ion cells not on the motor vehicle itself, but in another area. This makes it possible, on the one hand, to maintain the lithium-ion cells present in the motor vehicle battery. On the other hand, necessary work, for example for the replacement of one or more lithium-ion cells, can be carried out in such a way that it does not exist in the must be held in the tightest spaces, but rather the necessary space is provided.

According to a further embodiment, it is provided that the outer housing forms a first structure which acts shock-absorbing in the event of damage, in each case a plurality of lithium-ion cells combined form modules and the modules are arranged next to each other, wherein each module housing of a module forms a second structure, the shock absorbing acts in the event of damage, and a plurality of module housings are fixedly arranged in the outer housing. In this way, it is possible to produce a particularly mechanically stable fuse of the lithium-ion cells. While the outer housing with its first structure preferably in a frame construction is able to absorb smaller impacts such as force and possibly to be able to absorb by deformation, is ensured in a forwarding a force from the outer housing to the respective module housing, that by their second structure also a force absorption takes place or absorbed by a deformation force and thereby remain as unimpaired as possible in the module housing lithium-ion cells. A further development provides that, in the event of damage, first the first structure deforms and transfers force to one or more module housings during the deformation. The power transmission to the respective module housing leads to a deformation preferably a stabilized frame geometry, which is used as a secondary structure. A release of stress is preferably carried out via one or more covers, which has the module housing. These can change their shape to the outside and absorb forces acting here.

Furthermore, it is provided, for example, that an electrically conductive current lead leading out of a module housing is provided with a break-away device which triggers relative to the outer housing when the module housing is displaced and interrupts the current conduction. In this case, the current management can be used for example as a breakage protection. This ensures that in the event of damage the vehicle does not become live and thus one or more persons can be damaged. Damage to the electronic or electrical systems in the motor vehicle is prevented by such a power interruption.

According to a further embodiment, it is provided, for example, that one or more breakages are connected to terminal lugs of the respective lithium-ion cells. For example, it may be provided that terminal lugs are passed through the respective module housing, wherein the terminal lugs are replaced by plastic lugs. Fabric inserts are protected in a wall passage against mechanical displacement. At the same time, the plastic inserts serve to insulate the connection lugs. An implementation of the terminal lugs can be done for example by a cover of the module housing, which may have one or more recesses, in particular slots for this purpose. An electrical contact of the terminal lugs can be done outside of the module housing in the outer housing. For example, this is a terminal block laid in the outer housing to which the terminal lugs are connected when inserting the replaceable module housing in the outer housing. By attaching a breakage protection in this area, it can be ensured that, on the one hand, the power line between the power connection strip and the respective module housing is interrupted. On the other hand, it is ensured in the event of breakage that the hitherto current-carrying lines continue to remain insulated by the surrounding materials and, if necessary, not become current-contacting again as bare lines.

According to a further embodiment, it is provided that a first lithium-ion cell arranged in a module housing has a heat balance with a second, adjacently arranged lithium-ion cell, in each case along the extension of the first and the second lithium-ion cells different Heat developments are at least equalized. The first and the second lithium-ion cell can, for example, lie directly on top of one another, in particular as a planar electric current cell. Preferably, two lithium-ion cells lie on each other and can thus ensure a heat exchange with each other. Depending on the arrangement of the lithium-ion cells in their internal structure results in a different Lie heat development on the lithium-ion cell, that is, the lithium-ion cell is not the same temperature in all areas, but hereby differences , These differences can be counteracted by appropriate counter-arrangement of an adjacent lithium-ion cell, so that a temperature compensation takes place. Instead of a direct superimposition of two lithium-ion cells, an intermediate layer can also be arranged. This intermediate layer is preferably thermally conductive. According to one embodiment, it is provided that this intermediate layer is poured. According to another embodiment it can be provided that a thermally conductive foam is used. Another embodiment, in turn, provides that a heat-conducting material is provided between adjacent lithium-ion cells, which allows a heat exchange and in particular also a heat dissipation. A shock-absorbing material, preferably a foam, may be arranged around such cell packs formed from at least two contiguous lithium-ion cells. The shock absorbing material may, but does not have to be thermally conductive. It can also serve as insulating material. Preferably, it has a stability capable of absorbing impact on one or more lithium-ion cells or cell packets. For example, this can be used for this purpose foamed with nitrogen foam. In addition, such a material may be fire-retardant, especially non-burning or even fire-extinguishing. Thus, according to one embodiment, an open-pored foam and, according to another embodiment, a closed-pore foam can be used. If, for example, the closed-cell foam is produced with protective gas, this inert gas can be released during thermal heating of a cell packet, thus providing an extinguishing effect. Preferably, arranged in a module housing, opposing lithium-ion cells are each arranged rotated to each other. Several such lithium ion cells lying opposite one another can in turn have one or more free spaces. Such free spaces can also be filled with a thermally conductive material, for example by means of a flowable heat-conducting material.

According to one embodiment, it is provided that one or more lithium-ion cells, preferably lithium-ion cell packets, are used in a module housing. These are electrically connected to each other and the free space between the lithium-ion cells is filled with a mechanical stability-forming material, for example, shed. As mentioned above, this material can be a foam, be thermally conductive, but also have an insulating effect. In addition, there is the possibility that a heat dissipation is provided in a module housing. It is preferred that a temperature in a module housing does not exceed a predefinable maximum temperature as possible. For this purpose, it may be provided that the module housing itself internally has a cooling, for example. It may also be additionally or alternatively provided that the module housing is cooled from the outside. If, for example, an external cooling of the module housing is provided, a thermally conductive material is preferably used in the module housing in order to stabilize the position of the respective lithium ion cells arranged there, preferably to be able to provide additional shock-absorbing protection for a damage case and heat dissipation to the outside to be able to. If a cooling is provided in the module housing itself, according to one embodiment, a heat removal system is arranged in the module housing, which provides heat dissipation from the respective lithium-ion cells to the outside outside of the module housing. The module housings can be provided, for example, with one or more fans as well as with one or more heat sinks or heat exchangers. The outer housing in turn may have one or more heat dissipating Provide devices. This can be, for example, one or more switchable fans. It is also possible that the outer housing and / or the module housing can be connected to a cooling device of the motor vehicle. It is preferred that such a connection to the outer housing takes place, wherein inside the outer housing a heat dissipating flow is generated, so that a direct individual connection of each individual module housing to a motor vehicle cooling device, for example, is not additionally necessary. However, this is also possible according to another embodiment.

According to a further embodiment, it is provided that lithium ion cells arranged in a module housing have cell monitoring. The cell monitoring can be arranged in particular on the module housing, preferably by an independent module in which the cell monitoring is used circuit technology. The cell monitoring can also be arranged in the module housing and is in this case protected against damage from the outside by the module housing. The cell monitoring provides according to a development at least a cell voltage monitoring and a safety shutdown. For example, cell voltage monitoring may detect a total voltage of an associated module or modules, as well as, preferably, individual lithium ion cells. For example, a safety shutdown makes it possible to interrupt an electrically conductive connection of at least one lithium-ion cell to a current drain. According to one embodiment, it is provided that the safety shutdown can switch off one or more lithium-ion cells or cell packages or modules. According to one embodiment, it is provided that each module housing has a cell monitoring. According to another embodiment, it is provided that different module housings together have a single cell monitoring assigned. A data communication with an example, higher-level control device, preferably a battery control device, can be done by an additional line, in particular an information bus system. According to a further embodiment, it may be provided that for this purpose the current-carrying electrical line of the battery system or the

Motor vehicle is used. According to a further embodiment, it is provided that an information system, in which the motor vehicle battery is integrated with one or more modules, partially utilizes wire-based cable routes, for example with the involvement of a cable harness, but also wirelessly, for example by means of radio transmission. A cell monitoring, for example, be carried out remotely from the motor vehicle battery or a module housing. For this purpose, for example, a motor vehicle battery control unit can be used, which is located away from the actual motor vehicle battery in the vehicle. However, the control unit can also be arranged in or on the outer housing. The actual cell monitoring can then take place via one or more sensors, which are arranged in the outer housing or in a single module housing and are in communication with the control unit. In addition, there is the possibility that each module housing or the outer housing itself is a control unit available. Thus, for example, each individual control unit associated with a module housing can decide on the basis of the superordinate information which measures are to be taken in order to comply with predetermined parameters, for example a predetermined maximum temperature, a voltage to be delivered, a charging voltage or the like. According to one embodiment, it is provided, for example, that modules arranged within the outer housing with lithium-ion cells contained therein are connected as slave modules in a communication network. Due to its setting as the master, a default can be made via the higher-level battery control unit, which can execute the modules connected as slave accordingly. For this purpose, it is provided, for example, that in the individual module housings corresponding activatable devices such as cooling devices, breaker contacts such as relays or the like, information storage or other means are provided, which may alternatively or additionally be provided on the outer housing.

According to one embodiment, it is provided, for example, that a contacting board is arranged on a module housing. The contacting board is preferably located on a cover of the module housing according to an embodiment. The contacting board carries, for example, contacts for terminal lugs, for a cell compensation electronics, in particular with respect to currents and voltages to be picked up and delivered, a diagnostic electronics, preferably as described in the form of a slave module for a central battery control device and one or several plugs, for example for a positive pole, a negative pole or for a communication line. According to a further development, it is provided that a contacting board is arranged on a module housing, with which the arranged in the module housing lithium-ion cells for current transmission are electrically connected and the contacting board is detachably connected to the module housing, that in a damage, the contacting board at least partially detached, while a current-carrying electrical connection is interrupted. According to a further embodiment, it is provided that within the outer housing a plurality of module housing for lithium-ion cells are arranged, each having a frame and fixedly connected to the frame cover, wherein the lid are each configured as a rupture protection, wherein upon activation of the Berstsicherung is provided that an electrically conductive connection of the lithium-ion cells is interrupted in the module housing to the outside. For example, it can be provided that a cover of the module housing is firmly welded to a frame of the module housing. In this way, a mechanically very stable enclosure of the respective individual lithium-ion cells results, which are preferably secured in their position by corresponding built-in components in the respective module housing. As indicated above, this can be supported by means of a potting compound, a foam or by corresponding inserts or recesses. These measures can also complement each other. Such a cover, in turn, preferably has a shape which, when a force is exerted, leads to a deformation, in particular to a bursting. If an overpressure is generated in the interior of a module housing, this leads to an example, bursting at intended breaking points of the cover. This bursting leads to a stress relief of a housing structure of the module housing. It can be provided that an electronic or electrical connection is interrupted at the same time as part of such a rupture. According to one embodiment, it is provided, for example, that a Kontaktierungspla- tine is at least partially torn off, so that the module housing is then without electrical connection.

According to a further development it can be provided that in the outer housing of the motor vehicle battery, a contacting board is arranged on each module housing containing a number of lithium-ion cells, the contacts for one or more terminal lugs of the lithium-ion cells, a Cell balancing electronics for a voltage and / or an electric current, a diagnostic module in the form of a slave module for a central battery controller and one or more connectors for electronically connecting the lithium-ion cells to a parent power line for both having a communication line. Such a contacting board can be part of a cell monitoring. If there is a rupture of a part of a module housing, for example a cover, it can be provided that at least some of these components present on the contacting board are either interrupted in their respective lines or even destroyed themselves. It is preferably provided that in the case of an interruption, for example due to a fault, an error signal is automatically triggered to the higher-level control unit. This can then automatically ensure that the motor vehicle battery despite failure of one or more module housing supplies the necessary voltage or necessary current. For example, the control unit may also be able to determine a ranking of consumers to be supplied and, according to the actual available energy from the motor vehicle battery in the event of damage, automatically supply those consumers with energy according to a priority list, which are classified accordingly. In particular, this may relate, for example, to an automatic emergency call transmission, preferably with simultaneous automatic GPS location signal delivery, if a specific case of damage has been detected and forwarded.

According to a further embodiment, it is provided that at least one readable information memory is assigned to the outer housing. This information store can be, for example, an EEPROM or else a flash memory. On the one hand, the information store can have one or more maps in order to ensure in this way, in conjunction with a cell monitoring, that predefinable conditions with respect to parameters of one or more modules are met. On the other hand, for example, the information store can also receive information that is received via one or more sensors with respect to one or more modules. This information can be evaluated, for example, by means of a separate computer unit on the outer housing or in the control unit itself. It is preferably provided that a plurality of information stores are arranged in the outer housing, which are respectively assigned to different, arranged on the outer housing modules. In this way, a separate information system of the motor vehicle battery can be created. On the one hand, a redundancy can be generated, so that in case of failure of, for example, a cell monitoring on a module another module can still continue this task. On the other hand, it can be ensured in this way that, in the case of damage, at least with regard to some modules, data for later evaluation and damage processing could still be available. It is preferably provided that an information memory is arranged at least in a module housing, which is read from outside the module housing. The arrangement in the module housing a special damage security for the information storage is ensured. If, for example, an external force is applied to the motor vehicle battery in the event of damage, the probability that such a secured information store would rather cover a damage event is greater. stands. For example, it can also be provided that upon detection of a damage event, for example when a force is detected on the motor vehicle battery and / or on the motor vehicle, a data comparison between different information memories of the motor vehicle battery and / or of the motor vehicle takes place automatically. In this way it can be ensured that the information actually available is available in total independently of the storage location and in this way, on the one hand, a redundant operation is made possible after the damage has occurred and / or the damage data evaluated can be available for a damage assessment.

Another security results, for example, in that a plurality of housing modules, each with lithium-ion cells therein being exchangeably arranged in the outer housing. Preferably, the lithium-ion cells are packed together as cell packets and form with several cell packets each individual modules that are housed in the respective housing modules. This stability can be increased by virtue of the fact that the outer housing has, for example, a plurality of defined slots, into which housing modules adapted thereto can be inserted, preferably secured and electrically connected. For example, as stated above, the outer housing can have a central busbar, to which each individual housing module can be connected and with respect to which each housing module can also be disconnected in particular. An additional, preferably mechanical, fuse prevents the motor vehicle battery immediately having a total outer housing damage with internal housing module damage upon impact. Rather, can be created by corresponding braces and recordings by the defined slots additional stability in the outer case. According to a further embodiment, it can be provided, for example, that the outer housing has a lid which is non-destructively and repeatably detachable and reusable with a frame of the outer housing, wherein the lid points to a floor below the vehicle in a motor vehicle battery installed in a vehicle. In particular, this cover may also have a bursting protection. If there is a case of damage, the rupture protection can be triggered first, that is, the lid deforms outward. The fact that the cover is directed down to the roadway, an inner passenger cell of the motor vehicle is not destroyed by this deformation. Rather, occurring forces would be distributed over a surface by a corresponding planar geometry of the Innenfahrgastzelle associated outer housing side of the battery, which is remote from the lid. In addition, such a bursting allows that with appropriate deformation either the lid itself dissolves or such an opening is formed in the lid that one or more contained in the outer housing module housing get a free space within which they can then move, provided that their respective brackets are destroyed in the outer housing. In this way, an additional absorption of deformation energy can be provided. In particular, in this way there is the possibility that one or more module housings deform themselves either in the outer housing or can deform outwards, whereby one or more module housings can protrude from the outer housing also at least in part. For example, it is provided that an additional safeguard is provided between the module housing and the outer housing, so that, although module housings emerge from the outer housing, they can not move away from the vehicle beyond this individual fuse and its longitudinal extent. In this way prevents module housing can fly away as individual parts of the vehicle in case of damage.

A further embodiment provides, for example, for stabilization that in the outer housing a plurality of module housing are arranged, which have a subdivision, wherein one or more lithium-ion cells are each arranged in a first space and in a, separated from the first space second Space a Kontaktierungs- board and an information store are arranged. In this way, in the event of damage to a lithium-ion cell, the operation of the module housing can still be maintained in that appropriate information is sent immediately to the higher-level control unit and another cell monitoring and autonomous switching off of this module becomes possible. On the other hand, a special protection for the contacting board and the information memory is provided in this way. According to one embodiment, it is provided that the first or the second space have a lid attached as a boundary wall. This cover can in turn be provided with a bursting protection. A further embodiment provides that in the outer housing a plurality of module housing are arranged, each having a lid having at least one passage through which protrude through one or more terminal lugs of one or more lithium-ion cells. The protruding terminal lugs are electrically insulated, so that in case of damage, although an interruption of the electrical line takes place, the electrical lines themselves but remain isolated. If there is a force acting on the module housing, on the one hand the module housing itself can have a force-absorbing design, on the other hand the cover can be used for this purpose. If this deforms, this can lead to a breakdown of an electrical connection. The damaged module housing then provides no electric power but is in a safe, for a User of the vehicle secured condition. It is preferred if a cover of the module housing is welded to the remaining structure of the module housing.

According to a further aspect of the invention, an arrangement of a motor vehicle battery having a multiplicity of lithium-ion cells in a lower region of a motor vehicle along a subfloor is proposed, wherein the lithium-ion cells are arranged substantially horizontally in the underfloor region are.

A substantially horizontal arrangement of the lithium-ion cells in the underbody area has various advantages. On the one hand, an impact protection of the motor vehicle battery is provided by arrangement on the underbody area. On the other hand, a better accessibility is given for an exchange of lithium-ion cells, since by jacking up on a working platform, the motor vehicle battery is immediately accessible. On the other hand, it can be provided that a protective cover of the motor vehicle battery is provided in the underbody area, which also serves as underbody impact protection. This serves as a further protection against accidents. In particular, a sealed battery cell in the motor vehicle can be produced in this way, so that in case of damage a safety cell for the motor vehicle battery is provided. In addition, it is advantageous for the lithium-ion cells themselves due to the vibrations, shocks and material stresses acting on the motor vehicle when they extend quasi-lying. The forces acting on the motor vehicle and thus also on the lithium-ion cells can be better distributed in this way and also absorbed and absorbed in the cells. The risk of a material break due to stress is thereby reduced. A development provides that the lithium-ion cells are arranged in different module housings, which are secured to an outer housing of the motor vehicle battery and electrically separable connected to each other, and the outer housing has a longitudinal extent, in the installed state substantially horizontally along a Vehicle is running. A further embodiment provides that the motor vehicle is an electric or hybrid vehicle and in its underbody area has a holder which is suitable for the outer housing. Preferably, this is provided with a corresponding additional cover of the motor vehicle battery.

According to a further aspect of the invention, a use of coffee-bag cells for producing a lithium-ion battery for motor vehicle use in a hybrid or electric vehicle is proposed, wherein a plurality of coffee-bag cells are combined. form a module and several similar modules are housed and connected in a battery case, wherein the battery case is disposed in an underfloor region of the vehicle. The coffee bag cells as well as the modules and the outer housing may be configured as described above with respect to the commonly-considered lithium-ion batteries.

According to another aspect of the invention, it is proposed to provide a method of breaking an electrical connection of a motor vehicle battery comprising a plurality of lithium-ion cells, wherein the lithium-ion cells are arranged in modules and wherein the modules respectively be attached to a module housing before the module housings are housed in an outer housing, which is used interchangeably in the motor vehicle, and in a damage caused by the force on the outer housing and on one or more module housing, the current-conducting connection is interrupted due to the force. Furthermore, it can be provided that the current-conducting connection is interrupted in a region between the module housing and the outer housing. It is preferably provided that the current-conducting connection is interrupted in each case in a region within the module housing. In this way, it is ensured that in the event of damage, no current-conducting parts can come into contact, for example, with a housing.

Further advantageous embodiments and developments will become apparent from the following figures. However, the individual features resulting from the respective figures are not limited to the individual embodiments. Rather, these features can be linked to one or more other features of other figures from the general description described above for further embodiments. Furthermore, the embodiments shown in the figures are to be interpreted as illustrative and not restrictive, as well as the respective features contained therein. Show it:

1: a hybrid or electric vehicle with a motor vehicle battery arranged thereon in a schematic representation,

2 shows a plan view of a motor vehicle battery in a schematic view,

3 shows a preferred arrangement of lithium-ion cells for heat exchange, 4 shows an overview of various damage effects in various motor vehicle batteries,

FIG. 5 shows a proposed motor vehicle battery with outer housing and module housings contained in the outer housing, which can detach from one another upon occurrence of damage, FIG.

6 shows a plan view of a schematic motor vehicle battery with module housings arranged in an outer housing as well as cell monitoring shown by way of example,

Fig. 7: a schematic view of different lithium-ion cells and arranged therebetween material.

1 shows an exemplary schematic embodiment of a hybrid or electric vehicle 1. The hybrid or electric vehicle 1 has a motor vehicle battery 3 arranged in an underbody area 2. The motor vehicle battery 3 is shown schematically by individual lithium-ion cells 4, each having terminal lugs 5. The lithium-ion cells 4 may, for example, have a lithium metal as the anode. However, an embodiment is preferred in which the anode has a carbon as the storage medium and the positive electrode has a lithium transition metal oxide. A further embodiment provides that the lithium-ion Zeiien contain a Lithiuim- polymer cell. Such polymer-ion cells are preferably also referred to as "cofeece-bag cells" and are apparent, for example, from WO 2008/083920 cited above in the prior art and from the publications cited in the prior art thereon is fully referenced. The lithium-ion cells 4 preferably have an elongated extent, as shown in FIG. 1, and are therefore preferably prismatic. As is apparent from Fig. 1, the lithium-ion cells 4 are stacked one above the other, but they only have a certain height. The horizontal arrangement of the lithium-ion cells 4 results in a substantially higher mechanical stability of the respective cells compared to a vibration load, as they are exemplified by the respective arrows and the Cartesian coordinate system. As indicated schematically, typical vibration loads are highest in a vehicle in the z-axis. A standing arrangement of cells, as indicated by dashed lines, is therefore less favorable compared to the lying here by way of example lying arrangement. Damage to the cells as well as the Cell components or the components of the motor vehicle battery 3 are thereby better avoided.

FIG. 2 shows, in an exemplary embodiment, a second motor vehicle battery 6 with an outer housing 7 and a plurality of modules 8 made of further lithium-ion cells 4, wherein the modules 8 are each arranged in module housings 9. As shown, the module housings 9 can be firmly connected to each other. In such a case, the module housings 9 form a single assembled module housing as a second structure 10 of the second motor vehicle battery 6 for receiving forces which can act on the second motor vehicle battery 6 from the outside. The second motor vehicle battery 6, in turn, forms with the outer housing 7 a first structure 11 which is capable of being able to absorb and absorb forces from the outside either by its own deformation or by structural absorption of forces. For this purpose, for example, the outer housing 7 may have one or more struts 12, as indicated by dashed lines. The struts 12 can as cross struts as well as

Longitudinal struts be arranged. Preferably, these may have a certain extent in the interior of the second motor vehicle battery 6. However, they can also be arranged as a material reinforcement in a respective wall of the second motor vehicle battery 6. Furthermore, schematically indicated in the outer housing 7 a central busbar 13 is present. At this busbar 13, the respective lithium-ion cells 4 can be connected. This takes place, for example, when the module housing 9 is installed in the outer housing 7. According to the configuration of the module housing 9 that results from FIG. 2, a predetermined breaking point 14 is provided between the various modules 8. The predetermined breaking point 14 is indicated schematically as a dot-dash line. If a force effect is so great that the outer housing 7 is destroyed and the force acts directly on the module housing 9, this force effect can lead to the fact that the module housing 9 is separated along the predetermined breaking point 14. By arranging a variety of predetermined breaking points care can be taken that on the one hand, an absorption of the applied forces occurs, on the other hand, the existing in the respective housing parts of the module housing 9 lithium-ion cells 4 continue to be kept leak-proof. At the same time, in such a mechanical break, an electrical connection of the motor vehicle battery 3 can be interrupted in many ways. Thus, according to one embodiment, an electrically conductive current guide 15, which protrudes from the module housing and is connected to the busbar 13, thereby break. Preferably, a breakage fuse 16 is inserted into the electrically conductive current lead 15. The breakage protection 16 is indicated only schematically, it preferably provides a fracture plane, where in the event of breakage, the respective break ends are shielded by the remaining material of the breakage protection 16. An electrically conductive contact is avoided in this way with an outer housing 7, the busbar 13 or other electrically conductive object, preferably prevented. According to a further development, it is provided that a free space 17 between the lithium-ion cells 4 is filled with a material which preferably allows a further structural stability for the lithium-ion cells 4 arranged in the module housing 9. On the other hand, the material can be shock-absorbing. For example, it may be elastic or elastically plastic as well as plastically deformable, preferably for example in the form of a foam. A further embodiment provides that the material in a free space 17 between the lithium-ion cells 4 is thermally conductive. For example, a heat-conductive material can be arranged between the lithium-ion cells 4, as is apparent from EP 1 944 824 A2, to which reference is made in full. In this way, a cooling of a module 8 can be ensured.

FIG. 3 shows a particularly advantageous arrangement of a first lithium-ion cell 18 to a lithium ion cell arranged adjacently. The first and second lithium-ion cells 18, 19 each have a negative pole 20 and a positive pole 21. Dashed lines indicate three different regions in each cell 18, 19, which schematically indicate a different temperature distribution over the respective first or second lithium-ion cell 18, 19. The uneven heat distribution increases when stacked in the same direction of the cells on top of each other. In particular, in the field of contacting the electrical poles creates a high heat development, which increases accordingly in the same direction stacking. This requires a high requirement for a cooling management for such a constructed cell stack. Favor is therefore an opposing arrangement of the first and second lithium-ion cells 18, 19, so that a homogenization of the heat distribution takes place. In this way, the electrical contacts minus pole and positive pole 20, 21 are arranged twisted to each other. However, a heat homogenization can also take place in that a not completely opposite arrangement but at least twisted arrangement exists to each other. An improved heat exchange between the two cells 18, 19 is achieved by arranging a heat-conducting material. In this case, it can be provided, for example, that a targeted thermal bridge is achieved by special design of the material arranged between the cells. A thermally balanced cell packet is preferably the basic component of a module, with preferably only thermally compensating cell packets being arranged in a module. 4 shows in a schematic overview an effect of internal sources of error, for example due to external forces or leaking cells, overheating or the like. The damage event is shown as a jagged event. While on the left side is shown on top of each other, how such a case of damage affects in a conventional motor vehicle battery and finally detected from a local event all cells of the motor vehicle battery, especially in heat damage occurring, a local damage event in the on the the right side of Figure 4 superimposed motor vehicle batteries this remain limited to a single module. If there is a damage event there, the other modules are not affected. Rather, the separation of the individual modules with each other leads to the possibility of further use of the motor vehicle battery.

FIG. 5 shows, in a schematically exemplary embodiment, a multiplicity of mutually detached module housings 29, which were arranged individually in the outer housing 7. If, for example, an accident has occurred, the individual module housings 29 can be separated from one another. One embodiment provides that the module housings 29 already exist as individual housings and are secured together. If, for example, it is determined via a crash sensor that there is damage to the vehicle which is also relevant to the battery, automatic separation of the module housings 29, as shown, can take place. For example, this can also take place in that in such a case, the outer housing 7 releases one or more module housing. If there is a structural damage of the outer housing 7, this can also lead to a release of one or more module housings 29. The module housings 29 themselves may also be able to absorb energy without damaging the envelope of the module housing 29. According to one embodiment is provided in this as well as in the other embodiments described that the outer housing 7 as well as the module housing 29 are each closed, preferably closed fluid-tight. According to a further embodiment it can be provided that the module housing 29 is closed, the outer housing 7, however, at least partially permeable to air, for example by construction in the form of a lattice structure. Furthermore, there is the possibility that the module housings 29 have formed a single housing before an accident, but have separated due to the forces acting on predetermined breaking points. Preferably, the predetermined breaking points are designed so or the individual housing of the module housing 29, that in each of the resulting modules, a total voltage is less than 60 volts. For example, suppose For example, since a single lithium-ion cell applies a maximum voltage of 4.2 volts, a number of 14 cells may be provided in each individual module.

Fig. 6 shows a further exemplary embodiment of a third motor vehicle battery 30. This is also constructed in the form of a self-secured battery modular design, are provided in the self-contained module housing 31. By dividing the lithium-ion cells 4 into such self-secured cell modules, on the one hand, the number of damaged cells in the event of a fault and thus also the amount of potentially released energy can be limited. On the other hand, defective cell modules can be easily exchanged so that the entire battery does not have to be replaced. The protection of the cells against external influences is also improved by the modularization. The resulting from Fig. 6 third motor vehicle battery 30 has schematically indicated an integrated cell monitoring 32. The integrated cell monitoring 32 may be provided with cell voltage monitoring, cell balancing and a safety shutdown. For example, cell monitoring 32 may be connected to a communications network 33. For example, the cell monitoring may be connected to a contacting board 34, in particular, this may also be integrated with the cell monitoring 32. The contacting board 34 may, for example, have the terminal lugs connected, wherein on the contacting board, for example, a cell balancing electronics 35, a diagnostic electronics 36 and one or more plugs 37 may be arranged. For example, in one or more building blocks sitting on the bonding board 34, the corresponding various functions such as cell monitoring, voltage balancing, temperature monitoring and others may be accommodated. Preferably, the contacting board 34 is also connected via the communication network 33, for example with a higher-level control device 38. Preferably, the controller 38 is a motor vehicle battery controller. This can be connected via one or more further lines 39 with other control devices. The control unit 38 can serve, for example, as a master, while the cell monitoring 32 builds up as a slave module and the communication network 33 is connected to this master. On the contacting board 34, for example, an information memory 40 may further be arranged. However, the information storage 40 may also be arranged on the outer housing or each individual module housing may have such an information memory. In addition, dashed lines indicate that the respective module housings are held in place by slots in the outer housing. These inserts are indicated by dashed lines. For example, the modules can be inserted against stops 41 in order to specify the respective position of each individual module housing. A mechanical fuse can for example also be done via a lid which is placed on the outer housing 7. Also, the module housing may each have a cover 42 through which preferably the terminal lugs 5 pass. A module housing may further include a partition in a first and a second space. This is indicated by dashed lines for the module, which has the cell monitoring 32 schematically. This may be a fixed wall through which, for example, the terminal lugs 5 reach through. In this way, the cell monitoring can be secured against damage in case of damage of the lithium-ion cell in the module housing. The third motor vehicle battery 30 may further have a safety shutdown 43. The safety shutdown is, for example, an electronic module, which is preferably assigned to each individual module. Additionally or alternatively, the safety shutdown can also be assigned to the entire motor vehicle battery 30. In this case, the safety shut-off 43 preferably sits in the vicinity of a pole 44 of the third motor vehicle battery 30. In the system shown in FIG. 6, it is thus possible to ensure storage of a cell load via the respective information memory 40 over time , so that at any time the aging state of one of his modules or cells can be queried. By means of the safety shutoff 43, in turn, it can be ensured that the affected module is switched off in the event of a cell load exceeding a limit value or in the event of damage to a cell or, for example, the entire motor vehicle battery can be switched off in the event of damage to the vehicle.

Fig. 7 shows a schematic view of a module which is unfolded. As indicated, various lithium-ion cells 4 are alternately arranged in opposite directions with their respective electrical poles. Between the respective lithium-ion cells 4, a cooling device or a heat-conducting material for heat balance between the cells is arranged so that either a heat dissipated or can be distributed between the cells. If, for example, a heat dissipation between the cells is desired, this can be done with a device as disclosed in the above-mentioned EP 1 994 824 A2. If a heat distribution is desired, for example, a heat conductive, pourable plastic can be used for this purpose. Thermally conductive materials that groove plastics, for example, from WO 2001/096458 or from WO 2008/068274 forth, to which reference in this respect fully in the context of the disclosure reference is made.

Claims

claims

A motor vehicle battery (3) for an electric or hybrid motor vehicle (1), wherein the battery (3) comprises a plurality of lithium-ion cells (4) which are arranged separably connected to one another in an outer housing (7), which can be used interchangeably in a motor vehicle (1).

2. Motor vehicle battery (3) according to claim 1, characterized in that the outer housing (7) forms a first structure (11) which acts shock-absorbing in the event of damage, in each case a plurality of lithium-ion cells (4) summarized in each case modules (8 ) and the modules (8) are arranged next to each other, wherein in each case a module housing (9; 29) of a module (8) forms a second structure (10) which acts shock - absorbing in the event of damage, and a plurality of module housings (9; Outer housing (7) are fixed.

3. Motor vehicle battery (3) according to claim 1 or 2, characterized in that one, from a module housing (9; 29) leading out, electrically conductive current guide (15) with a break protection (16) is provided, which in a displacement of Module housing relative to the outer housing (7) triggers and interrupts the power supply (15).

4. motor vehicle battery (3) according to any one of the preceding claims, characterized in that in a module housing (9; 29) arranged first lithium-ion cell (18) heat balance to a second, adjacent arranged lithium ion cell (19), in which, in each case along the extent of the first and the second lithium-ion cells (18, 19) different heat developments are at least equalized.

5. motor vehicle battery (3) according to any one of the preceding claims, characterized in that in a module housing (9; 29) arranged, opposing lithium-ion cells (18, 19) are arranged in each case rotated to each other.

6. Motor vehicle battery (3) according to any one of the preceding claims, characterized in that a free space (17) between two lithium-ion cells (4) is filled with a preferably heat-conducting material.

7. motor vehicle battery (3) according to any one of the preceding claims, characterized in that in a module housing (9; 29) arranged lithium-ion cells (4) arranged on the module housing (9; 29) cell monitoring (32) ,

8. motor vehicle battery (3) according to claim 7, characterized in that the cell monitoring (32) at least one cell voltage monitoring and a safety shutdown (43) provides.

9. motor vehicle battery (3) according to any one of the preceding claims, character- ized in that within the outer housing (7) arranged modules (8) with lithium-ion cells contained therein (7) as slave modules in a communication network ( 33) are switched.

10. motor vehicle battery (3) according to one of the preceding claims, character- ized in that the outer housing (7) is assigned at least one readable information memory (40).

11. motor vehicle battery (3) according to any one of the preceding claims, characterized in that in the outer housing (7) a plurality of information storage (40) are arranged, which are each associated with different, in the outer housing (7) arranged modules (8) ,

12. motor vehicle battery (3) according to claim 11, characterized in that at least in a module housing (9; 29) an information memory (40) is arranged, which is read from outside the module housing (9; 29).

13. motor vehicle battery (3) according to one of the preceding claims, characterized in that a plurality of housing modules (); 29), each with lithium-ion cells (4) contained interchangeably arranged in the outer housing (7).

14. motor vehicle battery (3) according to any one of the preceding claims, characterized in that the outer housing (7) has a plurality of defined slots, in the adapted thereto housing modules (9; 29) can be used, secured and electrically connected.

15. Motor vehicle battery (3) according to one of the preceding claims, characterized in that the outer housing (7) has a frame with attached lid, wherein the lid is used as a rupture protection.

16. Motor vehicle battery (3) according to any one of the preceding claims, characterized in that the outer housing (7) has a lid which is non-destructively and repeatably detachable and reconnectable with a frame of the outer housing, wherein the cover with built-in motor vehicle battery ( 3) to a floor below the vehicle indicates.

17. motor vehicle battery (3) according to any one of the preceding claims, characterized in that within the outer housing (7) a plurality of module housing (9; 29) for lithium-ion cells (4) are arranged, each having a frame and fixed Having the lid associated with the frame, wherein the lid are each designed as Berstsicherung-, is provided upon activation of the bursting that an electrically conductive connection of the lithium-ion cells (4) in the module housing (9; outside is interrupted.

18. motor vehicle battery (3) according to one of the preceding claims, characterized in that on a module housing (9; 29) a contacting board (34) is arranged, with which in the module housing (9; Ion cells (4) are electrically connected to the current forwarding and the contacting board (34) so releasably connected to the module housing (9; 29), that in a damage, the contacting board (34) at least partially peels off and thereby a current-carrying e- lectric Connection is interrupted.

19. motor vehicle battery (3) according to any one of the preceding claims, characterized in that in the outer housing (7) to a respective module housing (9; 29) containing a number of lithium-ion cells (4) has a contacting board (34) is arranged, the contacts for one or more terminal lugs of the lithium-ion cells (4), a cell compensation electronics (35), a diagnostic electronics (36), preferably in the form of a slave module for a central battery control unit (38) and one or more plugs (37) for an electrical connection of the lithium-ion cells (4) to a higher-level power line and for a communication line.

20. Motor vehicle battery (3) according to any one of the preceding claims, characterized in that in the outer housing (7) a plurality of module housing (9; 29) arranged are, which have a subdivision, wherein in each case in a first space one or more lithium-ion cells (4) are arranged and arranged in a, separated from the first space second space a contacting board (34) and / or an information memory (40) are.

21. Motor vehicle battery (3) according to claim 20, characterized in that the first or the second space as a boundary wall having an attached cover.

22. motor vehicle battery (3) according to one of the preceding claims, character- ized in that in the outer housing (7) a plurality of module housing (9; 29) are arranged, each having a lid having at least one passage through which one or more terminal lugs (5) of one or more lithium-ion cells (4) protrude.

23. Arrangement of a motor vehicle battery (3) comprising a multiplicity of lithium-ion cells (4) in a lower region of a motor vehicle (1) as an underbody installation, wherein the lithium-ion cells (4) extend substantially horizontally in the Underbody area (2) are arranged.

24. The arrangement according to claim 23, characterized in that the lithium-ion cells (4) in different module housings (29) are arranged, which are secured in an outer housing (7) of the motor vehicle battery (3) and electrically connected with each other separable , And the outer housing (7) has a longitudinal extent, which extends in the installed state substantially horizontally.

25. Arrangement according to claim 23 or 24, characterized in that the motor vehicle is an electric or hybrid vehicle (1) and in its underbody area (2) has a holder for the outer housing (7).

26. Use of coffee bag cells for producing a lithium-ion battery for automotive use in a hybrid or electric vehicle (1), wherein a plurality of coffee bag cells combined form a module (8) and a plurality of similar modules (8 ) are housed and connected in a battery case, wherein the battery case is disposed in an underfloor region (2) of the vehicle.

27. A method for interrupting a current-conducting connection of a motor vehicle battery (3) comprising a multiplicity of lithium-ion cells (4) which are connected in modules (8). The modules (8) are each fastened in a module housing (9, 29) before the module housings (9, 29) are accommodated in an outer housing (7), which is used interchangeably in the motor vehicle, and in the event of damage Force acting on the outer housing (7) and one or more module housing (9; 29), the current-conducting connection is interrupted due to the force.

28. The method according to claim 27, characterized in that the current-conducting connection in a region between the module housings (9, 29) and the outer housing (7) is interrupted.

29. The method according to claim 27 or 28, characterized in that the current-conducting connection in each case in an area within the module housing (9, 29) is interrupted.