DE102014203506A1 - Battery assembly and vehicle with such - Google Patents

Abstract

The invention relates to a battery arrangement comprising a housing (2) for accommodating a variable number m of battery modules (9), at least one battery module (9) comprising a predetermined number s of battery cells (10) and being configurable in such a way that depending on Number of battery modules m accommodated in the housing results in a different electrical connection of the battery cells (10) in the battery module (9).

Description

The invention relates to a battery assembly and a vehicle, in particular an electrically driven vehicle (electric vehicle) with such a battery assembly.

Many of the electric vehicles known in the prior art are not developed from scratch, but arise based on known, developed for operation with internal combustion engines vehicles. Components that must be accommodated in the vehicle due to the electric drive are usually arranged either in such a way that they take the place of an attributable component or that they occupy a previously unused space. For example, high-voltage batteries (HV batteries) can be arranged to supply energy to an electric drive at the location of the vehicle, where the fuel tank is arranged in the vehicle powered by an internal combustion engine. Furthermore, HV batteries can be mounted in empty spaces, such as under the seats or in the trunk, as well as in flat floor or roof subassemblies.

It is known to use batteries of different capacity for the energy supply in electric vehicles. (The term "capacity" in this context may refer to a capacity with the unit watt-hours (WH) or a nominal charge of the battery with the unit ampere-hour (Ah).) This results in different dimensions of the battery case, which takes into account in the construction of the vehicle Need to become. Furthermore, the operating voltage required to operate the electric vehicle is not always the same. It can be different for different vehicles and / or use cases.

From the international patent application WO 2008035872 A1 a battery module is known, which is composed of several battery cells. The battery cells are sequentially stacked on a bottom plate. A cover plate is connected to the uppermost battery cell. The battery module has a sliding coupling structure by means of which two battery modules can be stacked.

The German patent application DE 10 2011 001 318 A1 discloses an electric vehicle with a modular battery system. By appropriate connection of several batteries the necessary battery capacity can be installed. The battery consists of several series-connected battery blocks, each consisting of twenty series-connected battery cells, two of which are joined together in one unit.

Compared to this prior art, the object is to provide a flexibly configurable battery assembly.

This object is achieved by a battery assembly as defined in claim 1. Advantageous developments emerge from the subclaims and features disclosed below.

The battery arrangement according to the invention comprises a housing for accommodating a variable number m of battery modules, wherein at least one battery module comprises a predetermined number u of battery cells and is configurable such that, depending on the number of battery modules accommodated by the housing m, a different electrical connection of the battery cells in the battery compartment Battery module yields.

The battery arrangement according to the invention or the battery housing according to the invention is suitable for accommodating one or more battery modules, wherein each battery module is set up to accommodate a number of battery cells. This results in a modular design that allows to realize a variety of possible combinations of battery cells and battery modules in the housing.

By battery arrangement is meant here any type of energy storage or energy converter in which storage elements, here called battery modules or battery cells, are interconnected. These include conventional battery cells and also storage elements for fuel fluids such as gasoline or diesel fuels, hydrogen, LNG, LPG. The housing structure can also serve to accommodate fuel cell stacks, which are provided for energy conversion.

Preferably, the battery cells of a battery module each have a cell voltage U_Zelle and it is at least one battery module configured so that p strands of each s battery cells of the battery module can be connected in parallel, where p is a divisor of the number u of battery cells in the battery module, so a battery module voltage of U_module = U_cell · s = U_cell · u / p results.

Preferably, a battery module can be configured alternatively such that for at least two alternative dividers p of the number u of battery cells in the battery module, in each case p strands of respectively s battery cells are connected in parallel.

Particularly preferably, all battery modules of the battery arrangement can be configured in the manner just described.

Advantageously, the configuration of a battery module is adjustable as a function of the number m of battery modules. For example, the interconnection of the battery cells in the battery modules may change if a further battery module is inserted into the battery arrangement or if a battery module is removed from the battery arrangement.

Preferably, the battery modules of the battery assembly are electrically connected in series, so that add the voltages U_Modul the individual battery modules to the total voltage U_Batterie the battery assembly.

It is not necessary that the battery modules are in turn designed as a housing. However, this is advantageous, wherein more preferably the battery module housing are constructed substantially the same.

Advantageously, the battery cells used are essentially identical in their nature. In particular, they may have substantially the same dimensions, electrical voltages and capacitances.

Preferably, the battery modules with respect to the number and electrical interconnection of the battery cells are constructed substantially the same.

The battery cells in the battery module are preferably connected in series and / or in parallel in such a way that the battery module has only two electrical connections led to the outside (anode / cathode, plus / minus).

Preferably, a number u = s * p of battery cells is used in a battery module, where s denotes a number of series-connected battery cells (string) and p denotes a number of series circuits connected in series (number of strings).

Preferably, the number u of the battery cells arranged in the battery module is a number with as many dividers as possible. This results in a particularly high flexibility in the use of the battery module.

The housing is preferably suitable for receiving at least two battery modules. By occupying or not occupying the locations provided for the arrangement of the battery modules, the capacity of the battery can be varied.

A minor special case is that only one battery module is used. In this case, the entire battery is constructed as described above for the construction of a single battery module.

In a further embodiment, the unitary battery modules can also consist of nonuniform cells. Thus, by way of example, instead of the series connection of two uniform cells, it is also possible to use a single cell with twice the cell voltage and correspondingly larger dimensions.

An inventive vehicle is equipped with a battery assembly, as described above. The battery assembly may serve, for example, as a traction battery of the vehicle.

Hereinafter, structural features of the case of the energy storage will be described.

The housing structure according to the invention has a first housing component, which is designed in particular as a receptacle and is provided with first cross members. The first cross member are connected to a bottom outer surface with a bottom of the receptacle. They have over a Bodenrandzone protruding ends, which are adapted for attachment to a vehicle assembly, in particular vehicle longitudinal members, so that the container structure is adapted to increase the torsional stiffness of a vehicle assembly, in particular to a vehicle longitudinal axis in the installed state.

The housing structure is provided for energy storage, in particular vehicle energy storage. These include on the one hand battery cells or battery modules but also storage elements for fuel fluids such as gasoline or diesel fuels, hydrogen, LNG, LPG. The housing structure can also be used to hold fuel cell stacks, which are intended for energy conversion.

About the connection of these first cross member with the bottom of the first housing member (the receptacle) on a bottom outer surfaces is a resilient, stabilizing connection, without the interior of the tub, which is to serve as a receiving space for energy storage components or other limited. Is the ground z. B. formed as a flat surface, it is reinforced and stabilized rib-like by the first cross member elements.

The fixation of the ends on a vehicle assembly, in particular on the vehicle longitudinal members of a floor assembly, then stiffens this structure. On the one hand by connection via the first cross member itself, on the other hand, but also in addition to the coupled with the vehicle assembly on the cross member receptacle, which already has a can have considerable inherent stability, which is then further increased by the additional cross member.

According to the invention, the housing has a first housing part or housing component that can be connected to the vehicle body, in particular a receiving trough, wherein the first housing part contributes at least one mechanical property of the vehicle when connected to the vehicle body, eg. B. stiffened a vehicle assembly or the vehicle body.

The at least one mechanical property preferably comprises in particular a lateral and / or a longitudinal torsional rigidity.

Preferably, the first housing part forms a part of the vehicle floor or a part of a vehicle floor structure, in which the first housing part is arranged below the actual vehicle floor.

Preferably, the first housing part is a bottom of the housing or of the housing component designed as a receptacle.

Preferably, the housing comprises at least one further housing part (second housing part). The second housing part may be designed as a cover, so that the housing formed from the first and the second housing part substantially forms a closed space. In one embodiment, the lid contributes to the at least one mechanical property of the vehicle. Alternatively, the lid does not contribute to a mechanical property of the vehicle.

Preferably, the first housing part comprises at least one longitudinally or transversely reinforced element (longitudinal member, cross member). With further advantage, the first housing part has a ribbed structure. Preferably, all or individual of the longitudinal members, cross member and / or ribs protrude beyond the dimension of the housing are formed in the edge region such that they are suitable for attachment to the vehicle body.

Preferably, the first housing part further comprises at least one releasably or non-releasably connected to the first housing part or connected Kant part for fixing the first housing part to the vehicle body. Additionally or alternatively, the at least one edge part contributes to the at least one mechanical property.

Preferably, the first housing part consists essentially of a material which is suitable for the purpose of contributing to a mechanical property of the vehicle. Preferably, the first housing part consists essentially of steel and / or aluminum and is more preferably manufactured as a deep-drawn part.

In the mentioned embodiment of the second housing part, in which the second housing part contributes to the at least one mechanical property of the vehicle, the second housing part is with further advantage of a solid material which is suitable for the purpose of contributing to a mechanical property of the vehicle , Preferably, the second housing part consists essentially of steel and / or aluminum.

In the alternative embodiment of the second housing part, in which the second housing part does not contribute to a mechanical property of the vehicle, the second housing part advantageously consists essentially of a light material which does not have to be suitable for contributing to a mechanical property of the vehicle. Preferably, the second housing part consists essentially of plastic.

The housing according to the invention is suitable for receiving energy stores, in particular from at least one battery cell existing high-voltage batteries. Furthermore, the housing is suitable for receiving gas tanks (eg natural gas (LPG or CNG), hydrogen bottles for a fuel cell vehicle, etc.), these being preferably fixed in a container (rack) which can be received by the housing. The housing according to the invention is furthermore suitable for accommodating energy converters, in particular one or more fuel cells (fuel cell stack).

Another aspect relates to a high-voltage battery arrangement and a battery housing for this, as well as a method for detecting and storing at least one parameter of a high-voltage battery.

Known high-voltage batteries must be connected to a separate power supply to activate battery management. Among other things, battery management has the task of recording and recording technical parameters of the battery. These parameters may include a temperature, a voltage and / or a state of charge of the battery or individual battery cells. If the battery is not located in the vehicle and connected (for example, during transport or storage of the battery), the battery management can only perform the described task when it is powered by an external power source. For this purpose, external DC-DC converters are used in the prior art.

The high-voltage battery arrangement described here, or the battery housing described here, makes it possible to simplify the monitoring of technical parameters.

For this purpose, a low-voltage battery (NV-battery) and / or a DC-DC converter can be arranged in or on the housing of the high-voltage battery. The term "low-voltage battery" refers to a battery with a voltage of less than 60 V, preferably 12 V to 48 V, particularly preferably 14 V. The term "high-voltage battery", however, refers to a battery with a voltage of more than 60 V, preferably 120 V to 400 V.

The battery management is powered by a low voltage source. To supply the NV-battery or the DC-DC converter can serve. The gelichspannungswandler converts the high voltage of the HV battery in a low voltage to supply the battery management.

The battery management is preferably set up to detect at least one parameter of the HV battery. The at least one parameter may be a parameter from the group comprising a temperature, a voltage, and a state of charge of the battery or individual battery cells.

Preferably, a data storage device connected to the battery management is provided, wherein the battery management is set up to store the at least one parameter by means of the data storage device.

Preferably, the battery management is activated ("woken up") at periodic intervals and performs the detection of the at least one parameter as well as the storage by means of the data storage device.

Preferably, the low-voltage battery is designed such that it is needed only to cover power demand peaks. Average powers are then provided by means of the DC-DC converter. Since this does not need to provide power peaks, it can be made smaller.

Preferably, the data stored in the data storage device may be communicated to an external device via a wired and / or wireless data interface. As wireless interfaces, for example, near-field communication interfaces (NFC), Bluetooth interfaces or WLAN interfaces can be used.

A corresponding method for detecting and storing at least one parameter of a high-voltage battery carries out the steps described for detecting and storing at least one parameter of a high-voltage battery.

The invention will be further explained with reference to the figures. In this case, the exemplary representation of the figures can not be understood as limiting. Possible embodiments of the invention can be formed from combinations of individual or all of the features illustrated as well as additionally or alternatively from features not shown in the figures. Directional indications such as above, below, longitudinal, transverse, right, left, rear and front refer to a vehicle arranged upright in a driving position, the longitudinal axis of which runs in the direction of travel, and are indicated from the perspective of the driver.

Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings. Showing:

1 a perspective view of a body shell with a highlighted, inventive housing structure;

2 a bottom view of the in 1 illustrated body shell with housing structure;

3 a perspective view of an embodiment of a housing structure according to the invention without body;

4a - 4c the housing structure 3 without lid with differently filled storage compartments; and

5a - 5f by way of example for the configurations p = 1, 2, 3, 4, 6 and 12, in each case the connection of the battery cells in a battery module.

1 shows the essential parts of a vehicle according to the invention 1 , Connected to the vehicle body 4 is the housing according to the invention, consisting of a first housing part 2 and a second housing part 3 , The first housing part 2 forms a housing structure and has a number of arranged in rib structure first cross members 5 on, which protrude beyond the dimensions of the housing and of which in this illustration every second for attachment to the vehicle body 4 serve. The first cross beams 5 Serve to increase the torsional stiffness of the vehicle and the absorption of forces in the y-direction, for example. In a side impact.

Also shown are two longitudinally arranged elements 6 , which also for attachment to the vehicle body 4 serve. The here as carrier brackets 6 trained elements For example, they can also be designed as longitudinal members which extend essentially over the entire length of the housing. In this embodiment, the elements serve 6 both the attachment of the housing to the vehicle body and the improved mechanical stiffness. The elements can also be designed such that they like the carrier brackets shown here 6 mainly serve only for attachment to the vehicle body. In this case they do not extend over a substantial length of the housing but are, for example, attached (eg welded or formed) to the corners of the first housing part. The Elements 6 serve mainly for the derivation of longitudinal forces (in the x direction) from the battery tray (first housing part 2 ) in the vehicle structure (eg during a frontal crash).

Furthermore, in 1 a longitudinal direction with cross members 5 connected, as edge part or profile rail 7 formed trained coupling element, which additionally contributes to the rigidity of the vehicle.

For attachment to the body serve the elements 5 (every second, see figures) and 6 , The crossbeams 5 Serve to increase the torsional stiffness and the derivation of lateral forces in a side crash. The Elements 6 serve mainly for the derivation of longitudinal forces from the battery tray (housing part 2 ) in the vehicle structure (eg during a frontal crash). The element 7 can be designed as a cantilever, but does not serve directly to attach the battery to the body. The part 7 is arranged inside a longitudinal member of the body. The first housing part is connected to the body by means of screw connections of the elements 5 with the depositor 7 in the side member. The inventors provide sketches for this purpose.

The longitudinal member may be made of aluminum, the insert 7 made of high-strength steel. This results in improved crash properties.

2 shows a view of the underbody of the vehicle according to the invention 1 , In this case, the same reference numerals designate substantially the same parts. In 2 is the embodiment of the rib-shaped cross member 5 to recognize.

3 shows a housing 8th consisting of the first housing part forming the housing structure according to the invention 2 and a second housing part 3 , The second housing part 3 is shown transparently, so that the arrangement of battery cells 9 in the case 8th can be seen. The first housing part 2 has a number of first cross beams arranged in rib structure 5 on, which with their ends over the dimensions of the housing 8th protrude and serve for attachment to the vehicle body. Also shown are the longitudinally arranged elements 6 , which also serve for attachment to the vehicle body.

The 4a to 4c show a battery assembly according to the invention or battery housing with a different number of battery cells. In 4a are m = 16 battery modules 9 arranged, each battery module consists of a number u = 12 of battery cells. For example, it could be an expansion stage with a capacity of 20 kWh, a range of 96 km and a weight of 270 kg. The places provided for the arrangement of further battery modules are in 4a not occupied, in 4b partially occupied and in 4c completely occupied. Here are in 4b m = 24 battery modules arranged. This results in a comparison with the embodiment of 4a capacity increased by 50%. For example, it could be an expansion stage with 30 kWh capacity, a range of 144 km and a weight of 364 kg. In 4c m = 32 battery modules are arranged. This results in a comparison with the embodiment of 4a 100% increased capacity. For example, it could be a further expansion stage with a capacity of 40 kWh, a range of 192 km and a weight of 452 kg. For example, the nominal voltage of the battery assembly could be 354V.

The battery modules are each electrically connected in series, so that add the voltages of the battery modules to the total voltage of the battery assembly.

In the embodiment described here, the number u of the battery cells arranged in a battery module is a number with as many dividers as possible. This results in a particularly high flexibility in the use of the battery module.

• • p = 1 Reihenschaltungen von s = 12 Batteriezellen; U_Modul = 12·U_Zelle
• • p = 2 Reihenschaltungen von je s = 6 Batteriezellen; parallele Verschaltung der 2 Reihenschaltungen; U_Modul = 6·U_Zelle
• • p = 3 Reihenschaltungen von je s = 4 Batteriezellen; parallele Verschaltung der 3 Reihenschaltungen; U_Modul = 4·U_Zelle
• • p = 4 Reihenschaltungen von je s = 3 Batteriezellen; parallele Verschaltung der 4 Reihenschaltungen; U_Modul = 3·U_Zelle
• • p = 6 Reihenschaltungen von je s = 2 Batteriezellen; parallele Verschaltung der 6 Reihenschaltungen; U_Modul = 2·U_Zelle
• • p = 12 Parallele Verschaltung von p = 12 Batteriezellen; U_Modul = U_Zelle

As an example, consider the case where u = 12 battery cells are used in a battery module. The voltage of a battery cell is called U_cell. The voltage at the electrical connections of the battery module is called U_Modul. The number u = 12 has the possible divisors p = 1, 2, 3, 4, 6 and 12. This results in the following possibilities for interconnecting the battery cells:

• • p = 1 series connections of s = 12 battery cells; U_module = 12 · U_cell
• • p = 2 series connections of s = 6 battery cells each; parallel connection of the 2 series circuits; U_module = 6 · U_cell
• • p = 3 series connections of s = 4 battery cells each; parallel connection of the 3 series circuits; U_module = 4 · U_cell
• • p = 4 series connections of s = 3 battery cells each; parallel connection of the 4 series connections; U_module = 3 · U_cell
• • p = 6 series connections of s = 2 battery cells each; parallel connection of the 6 series circuits; U_module = 2 · U_cell
• • p = 12 Parallel connection of p = 12 battery cells; U_module = U_cell

The 5a - 5f show exemplary of the possible configurations p = 1, 2, 3, 4, 6 and 12 of a battery module 9 with u = 12 battery cells each the interconnection of the battery cells 10 in the battery module 9 ,

Are in a battery arrangement of 4a For example, m = 16 battery modules installed, each having u = 12 battery cells and these are configured according to the above example to p = 2, the battery assembly has a total voltage U_Batterie = m · U_Modul = 16 · 6 · U_Zelle = 96 U_Zelle on. If the battery assembly now 8 more battery modules added, so that the configuration of the 4b with m = 24, the individual battery modules are reconfigured to p = 3. The result is a total voltage U_battery = m · U_module = 24 · 4 · U_cell = 96 U_cell. Due to the reconfiguration of the individual battery modules to p = 3, the total voltage of the battery arrangement has not changed despite serial addition of further battery modules. If the battery assembly in turn added 8 more battery modules, so that the configuration of the 4c with m = 32, the individual battery modules are reconfigured to p = 4. In this case, a total voltage U_battery = m · U_module = 32 · 3 · U_cell = 96 U_cell results. Due to the reconfiguration of the individual battery modules to p = 4, the total voltage of the battery arrangement has not changed despite serial addition of further battery modules.

Setting the individual battery modules to the desired configuration can be done manually on each battery module or automatically controlled.

For this purpose, corresponding switches could be provided on each battery module, which implement one of the configurations p depending on the switch position. Depending on the position of the switches, the battery cells in the battery module are switched in parallel or in series according to the set configuration p.

The switches can also be electronic switches in the form of semiconductor components, for example switching transistors or switching diodes, in which field-effect transistors (FET), bipolar transistors, diodes are used. Thyristors can also be used as electronic switches. The use of electronic switches has the advantage that they can be controlled by a control system, for example a battery management system. Thus, the configuration of the individual battery modules could be done automatically by a battery management. In battery management, information about the number m of battery modules inserted in the battery housing is present in this case. The number m of the battery modules can be programmed when inserting the battery modules, for example, in the battery management, or automatically determined by the battery management by appropriate sensors. Based on this information, the battery management can automatically configure the battery modules to the appropriate configuration p. A transmission of corresponding control signals and sensor signals can take place in a known manner, for example via corresponding signal lines, via a vehicle bus system, or also by radio.

It should be noted that the reference number 9 In all figures, instead of modules from battery cells, the alternative modules described above (eg energy storage and / or energy conversion modules such as pressure vessels, fuel tanks or fuel cell stacks) may also be different.

LIST OF REFERENCE NUMBERS

1

vehicle

2

first housing part (housing structure)

3

second housing part (cover)

4a

vehicle body

5

first cross member

6

Side members (carrier brackets)

7

Edge part (profile rail)

8th

casing

9

battery module

10

battery cell

11

Low-voltage battery

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

• WO 2008035872 A1 [0004]
• DE 102011001318 A1 [0005]

Claims (10)

Battery assembly comprising a housing ( 2 ) for receiving a variable number m of battery modules ( 9 ), wherein at least one battery module ( 9 ) a predetermined number u of battery cells ( 10 ) and configurable so that, depending on the number of housing ( 2 ) received battery modules m a different electrical interconnection of the battery cells ( 10 ) in the battery module ( 9 ). Battery assembly according to claim 1, wherein the battery cells ( 10 ) of a battery module ( 9 ) have a cell voltage U_Zelle and at least one battery module ( 9 ) is configurable such that p strands of each of s battery cells ( 10 ) of the battery module ( 9 ) can be connected in parallel to each other, where p is a divisor of the number u of battery cells ( 10 ) in the battery module ( 9 ), so that a battery module voltage of U_module = U_cell · s = U_cell · u / p results. Battery assembly according to claim 2, wherein at least one battery module ( 9 ) is alternatively configurable such that for at least two alternative dividers p of the number u of battery cells ( 10 ) in the battery module ( 9 ) each p strands of each s battery cells ( 10 ) can be switched parallel to each other. Battery assembly according to one of the preceding claims, wherein the configuration of the battery module ( 9 ) as a function of the number m of battery modules ( 9 ) is adjustable. Battery assembly according to one of the preceding claims, in which the battery modules ( 9 ) of the battery assembly are electrically connected in series, so that the voltages U_Modul the individual battery modules ( 9 ) to the total voltage U_Batterie of the battery assembly. Battery assembly according to one of the preceding claims, in which the battery cells ( 10 ) are substantially the same in their nature, in particular substantially the same dimensions, have electrical voltages and capacitances. Battery assembly according to one of the preceding claims, in which the battery modules ( 9 ) with regard to the number and electrical interconnection of the battery cells ( 10 ) are constructed substantially the same. Battery arrangement according to one of the preceding claims, in which the number u in a battery module ( 9 ) arranged battery cells ( 10 ) is a number with as many dividers as possible. Battery assembly according to one of the preceding claims, in which the housing ( 2 ) for receiving at least two battery modules ( 9 ) is designed. A vehicle comprising a battery assembly according to any one of the preceding claims.

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