Battery with a battery module and method for its operation
12087970 ยท 2024-09-10
Assignee
Inventors
- Michael Hinterberger (Gro?mehring, DE)
- Christoph Terbrack (Ingolstadt, DE)
- Christian Endisch (Geisenfeld, DE)
- Julia St?ttner (Ingolstadt, DE)
Cpc classification
H01M2010/4271
ELECTRICITY
Y02P70/50
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60L58/21
PERFORMING OPERATIONS; TRANSPORTING
H02J1/082
ELECTRICITY
H01M10/425
ELECTRICITY
H01M10/441
ELECTRICITY
Y02T10/70
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y02E60/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H01M2220/20
ELECTRICITY
H01M10/0525
ELECTRICITY
B60L50/64
PERFORMING OPERATIONS; TRANSPORTING
H02J1/109
ELECTRICITY
International classification
H01M50/502
ELECTRICITY
H01M10/42
ELECTRICITY
Abstract
A battery cell having first cell connectors, a galvanic cell and a first switching unit electrically coupled to the first cell connectors and the galvanic cell for electrically coupling the galvanic cell to the first cell connectors depending on a switching state of the first switching unit. The battery cell has second cell connectors electrically separated from the first cell connectors and a second switching unit electrically coupled to the second cell connectors and the galvanic cell for electrically coupling the galvanic cell to the second cell connectors depending on a switching state of the second switching unit.
Claims
1. A battery cell comprising: four first cell connectors configured as main terminals; a galvanic cell; and a first switching unit electrically coupled to the first cell connectors, wherein the galvanic cell is configured to be electrically coupled to the first cell connectors depending on a switching state of the first switching unit; two second cell connectors configured as secondary terminals that are electrically isolated from the four first cell connectors, wherein the second cell connectors are connected to two center taps of the first switching unit; and a second switching unit that is configured to be electrically coupled to the second cell connectors to electrically couple the galvanic cell to the second cell connectors depending on a switching state of the second switching unit.
2. The battery cell of claim 1, wherein the first switching unit and/or the second switching unit comprise at least one bridging switching element.
3. The battery cell according to claim 1, wherein the first switching unit is configured to electrically couple at least two of the first cell connectors to each other depending on one of several switching states of the first switching unit, and/or the second switching unit is configured to electrically couple at least two of the second cell connectors to each other.
4. The battery cell according to claim 1, wherein the first switching unit further comprises: a first switching element configured to electrically couple the second main terminal and the third main terminal, a second switching element configured to electrically couple the first main terminal and the fourth main terminal, a third switching element configured to electrically couple the first main terminal and the second main terminal, and a fourth switching element connected in series with the galvanic cell, wherein the first series circuit is connected between the second main terminal and the fourth main terminal such that a first potential terminal of the galvanic cell is connected to the fourth main terminal, and the second switching unit comprises a series circuit of three switching elements, the second switching element of the series circuit being directly connected to both potential terminals of the galvanic cell.
5. The battery cell according to claim 1, further comprising: a cell housing in which at least the first switching element and the second switching element are arranged which has at least one terminal contact for each of the cell connectors and each of the terminal contacts is configured to be electrically isolated from other terminal contacts.
6. The battery module comprising a first battery cell and a second battery cell formed according to the battery cell of claim 1, wherein pairs of first cell connectors of the first battery cell are electrically connected to pairs the first cell connectors of the second battery cell.
7. The battery module according to claim 6, wherein a second cell connector of the first battery cell is configured to be electrically connected to a second cell connector of the second battery cell.
8. The battery module according to claim 6, wherein the battery module is configured to be connected to at least six connection poles.
9. A motor vehicle with an on-board supply system comprising an electric machine as a drive device with the battery of claim 8 and the electric machine is directly connected to the battery.
10. The battery cell of claim 1, wherein the first switching unit and/or the second switching unit further comprise: at least one bridging switching element.
11. The battery cell according to claim 1, wherein the first switching unit further comprises: a first switching element configured to electrically couple the second main terminal and the third main terminal, a second switching element configured to electrically couple the first main terminal and the fourth main terminal, a third switching element configured to electrically couple the first main terminal and the second main terminal, and a fourth switching element connected in series with the galvanic cell, wherein the first series circuit is connected between the second main terminal and the fourth main terminal such that a first potential terminal of the galvanic cell is configured to be connected to the fourth main terminal, and the second switching unit comprises a series circuit of three switching elements, the second switching element of the series circuit being directly connected to both potential terminals of the galvanic cell.
12. The battery cell according to claim 2, wherein the first switching unit further comprises: a first switching element configured to electrically couple the second main terminal and the third main terminal, a second switching element configured to electrically couple the first main terminal and the fourth main terminal, a third switching element configured to electrically couple the first main terminal and the second main terminal, and a fourth switching element connected in series with the galvanic cell, wherein the first series circuit is connected between the second main terminal and the fourth main terminal such that a first potential terminal of the galvanic cell is configured to be connected to the fourth main terminal, and the second switching unit comprises a series circuit of three switching elements, the second switching element of the series circuit being directly connected to both potential terminals of the galvanic cell.
13. The battery cell according to claim 3, wherein the first switching unit further comprises: a first switching element configured to electrically couple the second main terminal and the third main terminal, a second switching element configured to electrically couple the first main terminal and the fourth main terminal, a third switching element configured to electrically couple the first main terminal and the second main terminal, and a fourth switching element connected in series with the galvanic cell, wherein the first series circuit is connected between the second main terminal and the fourth main terminal such that a first potential terminal of the galvanic cell is configured to be connected to the fourth main terminal, and the second switching unit comprises a series circuit of three switching elements, the second switching element of the series circuit being directly connected to both potential terminals of the galvanic cell.
14. The battery cell according to claim 1, further comprising: a cell housing in which the first switching element and the second switching element are arranged which has at least one terminal contact for each of the cell connectors and each of the terminal contacts is configured to be electrically isolated from other terminal contacts.
15. The battery cell according to claim 2, further comprising: a cell housing in which the first switching element and the second switching element are arranged which has at least one terminal contact for each of the cell connectors and each of the terminal contacts is configured to be electrically isolated from other terminal contacts.
Description
BRIEF DESCRIPTION OF THE FIGURES
(1) Below are the embodiment examples of the invention shown in the following pictures:
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DETAILED DESCRIPTION
(19) The exemplary embodiments explained in the following are preferred embodiments of the invention. In the exemplary embodiments, the respective components of the embodiments represent individual features of the invention, to be considered independently of one another, which also further develop the invention independently of one another. In addition, the embodiments described can also be supplemented with other previously described features of the invention.
(20) In the figures, the same reference symbols always designate elements with the same function.
(21)
(22) Each of the battery modules 10, 12, 14, 16, 18, 20 has three series circuits 22, 24, 26 of battery cells 46 (
(23) The semiconductor switching elements Se1, Se2, Se3, Se4 as well as the semiconductor switching elements described in the following currently exist as a kind of MOSFET. In alternative embodiments, naturally another kind of semiconductor switching element may be provided, for example an IGBT or the like.
(24) The number of semiconductor switching elements between the battery modules shown in
(25) Depending on the closing of the semiconductor switching elements between the battery modules, various combinations and therefore either series or parallel connections of battery modules can be achieved. If, tor example, in a multi-phase system, all battery modules 10, 12, 14, 16, 18, 20 shown are assigned a single phase potential and only the battery modules 10, 14, 18 or individual battery cells of these battery modules are required for generating this potential phase, for example phase 1, the module matrix offers some advantages.
(26) On one hand, faster bypassing of battery modules that are not currently required, here for example battery modules 16 and 20, is possible by realizing a direct connection between the modules 10 and 18 by closing the intervening semiconductor switching elements. With this, battery modules 16 and 20 need no longer carry additional current. On the other hand, these battery modules, now also including the battery module 12 which is also not required, can be used for potential generation of one or more additional phase potentials.
(27) In a schematic cutaway view,
(28)
(29) By means of a control unit 60, the battery 48, specifically its semiconductor switching elements, especially comprising its semiconductor switching elements Se1, Se2, Se3, Se4, are operated such that the three phases of the alternating current for the synchronous motor 72 can be supplied appropriately by operating the battery 48 in the manner of a multi-level energy converter.
(30) An exemplary circuitry with assignment of individual battery modules to different phases is, for example: battery modules 10, 14 and 18 to phase 1, battery module 12 to phase 2 and battery module 16 and 20 to phase 3.
(31) In a further schematic representation,
(32) Because of the change in the phase potentials over time compared with
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(35) It is recognizable in
(36) The first and the third module connections 1, 3 can be electrically coupled with one another over the series circuit 22 consisting of four battery cells B1, B2, B3, B4 and two additional semiconductor switching elements S9 and S10. Correspondingly, the module connections 2 and 4 can be electrically coupled with one another over the series circuit 26 consisting of battery cells B9, B10, B11, B12 and semiconductor switching elements S29, S30.
(37) A center connection 28 of the semiconductor switching elements Sb1, Sb2 connected in series can be coupled electrically over the series circuit 24 consisting of battery cells B5, B5, B7, B8 and semiconductor switching elements S19 and S20 with a center connection 30 of the series circuit of the semiconductor switching elements Sb3 and Sb4. The series circuits 22, 24, 26 in this case are of essentially the same construction. This may also be made different if necessary.
(38)
(39) The galvanic cell 12 is designed as an electrochemical cell and has two electrodes, which form a first potential connection 42 and a second potential connection 44. In the present configuration, the galvanic cell 12 is designed as a lithium ion cell. In alternative configurations, another galvanic cell may also be provided here, for example a lead-acid cell or the like.
(40) The battery cell 46 has a first cell connection 34, which is directly electrically coupled with the first potential connection 42 of the galvanic cell 12. In addition, the battery cell 46 has a second cell connection 36, which is electrically coupled over a first semiconductor switching element 50 of the battery cell 46 with a second potential connection 44 of the galvanic cell 12. The first semiconductor switching element 50 in the present case is made of a transistor, namely a field effect transistor of the MOSFET type. Naturally, another transistor, for example an IGBT or the like, may also be used alternatively.
(41) The battery cell 46 also comprises a third cell connection 38, a second semiconductor switching element 32, which may be essentially designed like the first semiconductor switching element 50, and a fourth cell connection 40, which is electrically coupled over the second semiconductor switching element 32 with the first potential connection 42 of the galvanic cell 12. Thus in the present case the battery cell 46 has four cell connections 34, 36, 38, 40. Through this specific circuit structure of the battery cell 46, specific functionalities can be achieved during the operation of a battery module 10 constructed with these battery cells 46.
(42) It is apparent from
(43) Through the battery cells 46 it is possible to make a potential of the respective battery modules 10, 12, 14, 16, 18, 20 variable, even with respect to the potential to be provided at the module connections 1, 2, 3, 4. With the circuit structure of the battery cells 46 it is even possible to achieve alternating currents as needed at the module connections 1, 2, 3, 4. In connection with the circuit structure of the battery 48 according to
(44) As is apparent from
(45) In addition, the battery 48 comprises a control unit 60 to which all the semiconductor switching elements of the battery 48, the battery modules 10, 12, 14, 16, 18, 20 and also all battery cells 46 are connected. By appropriately switching the semiconductor switching elements, not only can the individual battery cells 46 in the battery modules 10, 12, 14, 16, 18, 20 be activated or deactivated as needed, to supply a potential as needed at the module connections 1, 2, 3, 4 according to the respective specified electrical alternating current, but the possibility also exists of further increasing the flexibility by activating respective battery modules. In particular, the possibility exists of completely activating or deactivating individual battery modules or even making them available in normal operation to another potential supply line. In this way it is possible for the battery 48 not only to accomplish the functionality of a three-phase inverter of the multi-level energy converter type, but also to supply a plurality of greatly differing electrical potentials almost simultaneously. In this process, with the circuit structure according to the invention, it is possible to supply both positive and negative electrical potentials against a battery reference potential connection and/or battery reference potential. In addition, it is also possible to vary amplitudes and/or phase shifts in the case of alternating current potentials when, for example, this is desired in normal operation of the synchronous motor 72 or the like.
(46) The layout of the battery modules 10, 12, 14, 16, 18, 20 can take the form of a module matrix, wherein the battery modules 10, 12, 14, 16, 18, 20, in contrast to a pure series connection thereof, are connected with more than just two adjacent modules over the semiconductor switching elements designed as circuit breakers, giving the possibility of connecting the battery modules together in any order, separating them galvanically, bypassing individual battery modules or generating individual DC potentials, for example using them for a vehicle electrical system power supply.
(47) The following additional effects can also be achieved with the invention:
(48) For example, utilization of the resources of battery cells temporarily actually switched as inactive can be realized by modularity of the battery cells. In contrast to the case of multi-level energy converters of the prior art, the modularity of the topology according to the invention can be achieved, for example, not by simply connecting battery modules in series, for example within a phase, but to some extent by a module matrix, in which a battery module can be connected with more than two nearby battery modules, for example z nearby battery modules, wherein z corresponds to the number of power switches via which the respective battery module can be electrically connected with other battery modules. Thus z different current paths through one module are possible.
(49) This functionality facilitates or enables the formation of positive and negative initial potential levels; in other words, it thus integrates the ability for polarity reversal of the initial potentials. It is also possible to equip each of the individual battery modules in the battery with a different number of semiconductor switching elements outside of the battery module, for example zi, wherein i corresponds to the i-th battery module, so that the number of module connections can vary. This is advantageous in that the number of nearby battery modules of a battery module located in the interior of a battery can differ from that of a module on the edge of the battery. This modularity need not be limited to one plane of the battery, i.e., to two dimensions, but a three-dimensional structure of a large number of battery modules is also conceivable.
(50) The allocation of the battery modules to the individual phases and the production of the gate signals for the semiconductor switching elements between the individual battery modules can be generated using appropriate modulations/actuation methods. In this process the generation of the switching signals for the semiconductor switching elements between the battery modules can be selected to occur in such a form that ideally these only change at a low frequency, and thus the occurring switching losses are small. This is recognizable, for example, from the allocation of battery module 12 in the previously shown
(51) In view of the existing advantage that individual battery modules with the suggested topology can likewise be used for supplying a constant DC potential, for example, battery module 12 in
(52) As was previously mentioned, the module matrix need not be limited to one plane, but can also be expanded to multiple planes.
(53) Likewise, different connection topologies of the battery cells 46 can be realized within the various battery modules. A large selection of topology variants with p parallel-connected battery cells or sections as well as m series-connected battery cells can be implemented.
(54)
(55) The topology shown allows a polarity reversal, in other words, it has the functionality of producing positive and negative output potential levels. Thus in addition to the individual battery modules it also increases the number of possible potential levels of the multi-level energy converter supplied with the battery 48.
(56) Around the battery module 10 are four external semiconductor switching elements Se1, Se2, Se3, Se4 for combination/connection with other battery modules. The semiconductor switching elements Sb1, Sb2, Sb3, Sb4 within the battery module additionally allow the connection or the uncoupling of individual sections with/from one another as well as the possibility of current conduction starting from any of the external semiconductor switching elements Se1, Se2, Se3, Se4 through the battery module to another arbitrary one of these four semiconductor switching elements.
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(59) It is also apparent from
(60) Terminal line 52 is assigned a zero potential, while the connection lines 54, 56, 58 are assigned to respective phases L3, L2, L1.
(61) According to the number of terminal lines 52, 54, 56, 58, the connection switching elements 62 have switching elements (not shown) which make it possible to individually electrically couple one of the four module connections 1, 2, 3, 4 to one of the battery modules 10, 12, 16, 18 respectively with one of the terminal lines 52, 54, 56, 58. In this way, the battery modules for the potential supply can be arranged in almost any desired way.
(62) The semiconductor switching elements, especially the semiconductor switching elements SE 1, SE 2, SE 3, SE 4 and the connection switching elements 62, are activated by the control unit 60, depending on the electrical potentials predetermined by the battery 48 in order to supply the specified electrical potentials at the battery terminals.
(63)
(64) It is recognizable that the maximum service capacity has a normalized potential value of 2. An additional curve 90 characterizes the total service capacity available from the battery 48 when all battery modules of the battery 48 are used. The curve 92 characterizes an energy buffer, which corresponds to a difference between the curve 90, which in the present case corresponds to the normalized potential with the value of 3, and the maximum service capacity actually utilized. For normal operation of the battery 48 to supply three-phase alternating current, the battery 48 would only have to be designed for the maximal service capacity actually utilized according to the curve 88. Thus with regard to this application the energy buffer 92 represents a kind of oversizing, which not only can provide flexibility of the battery 48, but also can provide reliability, since it makes it possible to exclude defective battery modules or malfunctioning battery modules from utilization and instead introduce battery modules of the energy buffer corresponding to the utilization.
(65) The essentially comparable situation also arises for multiples of three-phase alternating currents, for example six-phase alternating currents, nine-phase alternating currents or the like. Similar orders of magnitude for the energy buffer result.
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(68) As a result it is possible to use temporarily deactivated battery modules or battery cells for supplying other phase potentials. This is possible, among other things, because the phase potentials, which represent individual alternating currents, are shifted in their phase position relative to one another. The phase shift between the individual phases is preferably the same for all the phase potentials relative to one another, wherein at least one value of the phase shift may be dependent upon the number of phases. Thus in the case of a three-phase alternating current, the phase potentials are usually phase-shifted by about 120? relatively to one another. Corresponding considerations apply for a larger number of phases.
(69) It is also possible to realize a variable neutral point shift if the battery 48 is used to supply the three-phase alternating current as an alternating current based on a neutral point. In this case it is possible for the neutral point of the phase potentials to be propagated through the battery 48 or the battery module. Naturally, the possibility also exists of integrating several neutral points or phase taps that may be activated or deactivated as needed.
(70)
(71) In addition, the battery cell 200 has a second switch unit 216, which electrically couples the galvanic cell 12, depending on a respective switching status, with the second cell connections 212, 214.
(72) For the electrical coupling, the first switch unit 218 comprises two switching elements 30, 32. The switching element 30 is connected between the second and the third cell connection 36, 38, while the switching element 32 is connected between the first and the fourth cell connection 34, 40. The first switch unit 218 also comprises a switching element 202 which, depending on its switching status, electrically couples the first and the second cell connection 34, 36. Finally, the first switch unit 218 comprises a switching element 204, which forms a series circuit with the galvanic cell 212, connected to the second and fourth cell connections 36, 40. In this configuration the potential connection 42 of the galvanic cell 12 is electrically coupled with the cell connection 40 and the switching element 204 is electrically coupled over one of its two connections with the cell connection 36. In this way, fundamentally a functionality can be provided as was already explained based on
(73) Also, the second switch unit 216 is connected directly to the potential terminals 42, 44 of the galvanic cell 12, comprising a series circuit made of three switching elements 206, 208, 210. This series circuit is connected directly to the potential terminals 42, 44. The second cell connections 212, 214 are connected to two center taps of this series circuit. In this way, using the switching element 210, which in the present case represents a bypass switching element, bypassing the battery cell 200 for the second switch unit with regard to the second cell connections 212, 214 can be accomplished.
(74) A bypass functionality can correspondingly also be achieved with the first switch unit 218. Depending on the polarity and switching status, however, the corresponding switching elements are to be activated here. In the case of bypass, in particular the switching element 204 can be in the off switching status.
(75) Because of the circuit structure of the battery cell 200 in the present case it is possible to use the galvanic cell 12 in the simultaneous provision of two potentials electrically separated from one another. Thus the galvanic cell 12 can be used for supplying a first electrical potential in that a potential value can be made available over the first switch unit 218 to the first cell connections 34, 36, 38, 40, or it can be used for supplying a second electrical potential in that a potential value can be made available over the second switch unit 216 at the second cell connections 212, 214. Thus the battery cell 200 can be utilized for providing a respective electrical potential depending on the respective switching status of the first and the second switch units 216, 218.
(76) The switching element 202 of the first switch unit 218 can be used to switch the polarity of the galvanic cell 12 appropriately when an electrical potential is to be provided over the first cell connections 34, 36, 38, 40. As a result of the specific circuit structure, a plurality of very different utilization possibilities can be achieved for the galvanic cell 12 or the battery cell 200.
(77)
(78) At the opposite end of the cascaded or series-connected battery cells 200, the first and the third cell connections 34, 38 of the corresponding battery module 200 are jointly connected to an additional module connection 224. In
(79) Alternatively, the cascade or series circuit can also be executed such that a second cell connection 36 of a respective battery cell 200 is connected to a third cell connection 38 of the respectively immediately following battery cell 200 and a fourth cell connection 40 of the aforementioned battery cell 200 to the first cell connection 34 of the immediately following battery cell 200. The cascade or series connection of the battery cells 200 can also be achieved in this way. Independently of the connection type selected in this regard, however, the same functionality can be achieved, wherein only the first switch unit 218 is to be correspondingly modified with regard to the switching status of its switching elements 30, 32, 202, 204.
(80) Depending on the switching status of the first switch unit 218, the die galvanic cell 12 can be connected at least partially in parallel or at least partially in series to produce an electrical potential at the module connections 222, 224. In this way, particularly great flexibility is achieved with regard to the utilization of the battery cells 200. In particular, the configuration according to
(81) It is also apparent from
(82) In the existing configuration in
(83) If a battery cell 200 is used for supplying the electrical potential to the module connections 226, 228, the first switch unit 218 deactivates the use of the galvanic cell 212, in that at least its switching elements 32, 204 are switched into the off status. Correspondingly, the switching elements 206, 208 of the second switch unit 216 are switched into the on status and the switch unit 210 is switched into the off status. As a result, the electrical potential between the potential terminals 42, 44 of the galvanic cell 12 is also present at the second cell connections 212, 214. Depending on the desired potential at the module connections 226, 228, a corresponding number of battery cells 200 is activated to supply the potential at the module connections 226, 228.
(84) In this operating state it can be provided that the switch unit 30 or the switch unit 202 of the first switch unit 218 is activated in order to simultaneously enable the supply of a potential at the module connections 222, 224 using others of the battery cells 200. For this purpose a corresponding activation is performed on the battery cells 200 that are mpt needed for providing the electrical potential at the module connections 226, 228.
(85) In an additional schematic circuit diagram,
(86) In the configuration of the battery 240 according to
(87) The battery 240 includes further connection poles 242, 244, 246, 248, 252, 254. Thus, the embodiment according to
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(89) A difference between the embodiment according to
(90) In addition, the invention allows a number of further combination possibilities and circuit structures, as shown for example with battery 260 according to
(91) Battery 260 differs from battery 250 as shown in
(92) Battery module 258 differs from battery module 220 according to
(93) A further variant of a battery module is the battery module 256, which is also based on the embodiment of the battery module 220 according to
(94) Of course, almost any other combination of battery cells and battery modules can be provided to achieve combinations that are particularly suitable or adapted for specific applications. All in all, the invention thus allows the creation of a particularly flexible and highly dynamically adaptable battery that can be easily adapted to specific applications. The special design of the battery cells 200 makes this possible. The switching elements in this case are formed by semiconductor switching elements and are preferably connected to the control unit, which ensures a suitable switching operation of the switching elements.
(95) The essential advantage of the presented patent idea is that battery cells, which were originally assigned to the generation of a single phase voltage, but are temporarily unused due to the current voltage value or similar, can be used for the generation of other phase voltages.
(96) Consequently, the battery system is optimized in such a way that preferably at all times the entire available battery potential can be used.
(97) This allows the freedom to create a flexible allocation of battery cells and/or battery modules or batteries to different, for example sinusoidal, phase voltages. This means that these contribute their current voltage value to the respectively assigned phase voltage.
(98) Depending on the selected frequency values or optimization algorithms, the allocation can be varied at will over time, for example before and/or during operation. The allocation can be done for time reasons, but can also result from any other criterion. The allocation can be fixed or variable for each individual cell. The allocation can change between fixed and variable once or several times.
(99) Compared to conventional multilevel energy converters, the number of effectively used battery cells or battery modules can be increased. The additional battery cells or battery modules can be used to increase the performance of the battery system or battery. For example, the output voltage of the multilevel energy converter can be increased. With the same current capability of the voltage source, the power can be increased proportionally to each newly added voltage source. On the other hand, if the power requirements remain the same, increasing the voltage level can result in a lower current load. This results, for example, in lower power losses and less aging of the battery cells or battery modules.
(100) The proposed idea allows the design of output voltages with any number of phases m. The individual phase voltages can have any shape, such as sinus wave, triangle, sawtooth, etc., flexible phase shifts to each other, and their amplitudes (V.sub.AC) can be individually adjusted as required.
(101) It should be noted that the values of the actually used voltage/battery potential can change over time based on the respective phase shifts of the output voltages of the multilevel energy converter to be generated. This can be examined and considered depending on the application.
(102) In the case of an equidistant phase shift between the individual phase voltages, which is usually present, especially in an electrical machine, the value of the actually used battery potential and thus also the value of the unused utilization potential is approximately constant.
(103) The described idea also offers the freedom to generate output voltages with a positive and/or negative DC offset. For this purpose, only the number of battery cells or battery modules, which are flown through in such a way that they make a positive voltage contribution to the respective phase voltage, has to differ from the number of battery cells or battery modules, which make a negative voltage contribution to the respective phase voltage within a period.
(104) The selection of the individual battery cells or battery modules for the respective phase voltages, the determination of currently unused battery cells or battery modules, an optimized partitioning of the battery system in this respect as well as maximum efficient control of the built-in power semiconductors is carried out with a control device that can use corresponding control algorithms.
(105) It can be freely decided whether all or only a part of the newly accessible utilization potential is used. For example, only a part of the battery cells or battery modules can be used to ensure the symmetry of the multi-phase system in case of failure of battery cells or battery modules. In another case it is possible to create asymmetrical multi-phase systems, for example to better compensate the load by asymmetrical loads in case of failure.
(106) Furthermore, it is possible to create multi-phase voltage systems with a smaller total number of single voltage sources. For example, the output voltage of a battery system or battery determines how many cells are connected in series in this battery system or battery. If a battery system is to be created with fewer battery cells or battery modules, it is not possible to create it without lowering the desired output voltage specification. With the solution proposed here it is possible to create battery systems or batteries with a smaller number of battery cells or battery modules while maintaining the same output voltage. This becomes possible by temporarily unused battery cells or battery modules of a particular phase being able to deliver their voltage contributions to one or more other phases, for example by allocating battery cells or battery modules to phases in a variable way.
(107) Another advantage resulting from the proposed idea would be the reduction of the volume and weight of the battery system or battery. In case of the actual utilization of the entire utilization potential by allocating temporarily unused battery cells or battery modules to other phase voltages, a significant number of battery cells or battery modules can be saved, which in turn can reduce the installation space or required space of the battery.
(108) It is also possible to use the newly developed potential of battery cells or battery modules to compensate for failed battery cells or battery modules. If a battery cell or a battery module from a string fails, it can be compensated by one or more temporarily battery cells or battery modules.
(109) Furthermore, the following effects can be achieved with the invention:
(110) The resource utilization of battery cells that are actually inactive at times can be realized, for example, through the modularity of battery cells. In contrast to prior art multi-level energy converters, the modularity of the topology according to the invention is not characterized by a mere series connection of battery modules, for example within a phase, but to a certain extent by a module matrix in which one battery module can be connected to more than two neighboring battery modules, for example z neighboring battery modules, where z corresponds to the number of circuit breakers via which the respective battery module can be electrically connected to other battery modules. Thus, z different current paths through one module are possible.
(111) This functionality facilitates or enables the formation of positive and negative output voltage levels, i.e. it integrates the ability to reverse the polarity of the output voltages. It is also possible to equip individual battery modules in the battery with a different number of semiconductor switching elements outside the battery modules, for example z.sub.i, where i corresponds to the i-th battery module, so that the number of module connections can vary. This is advantageous in that the number of neighboring battery modules of a battery module located inside a battery can differ from that of an edge battery module of the battery. This modularity does not have to be limited to one battery level, e.g. two-dimensional, but a three-dimensional structure of numerous battery modules is also conceivable.
(112) The allocation of the battery modules to the individual phases as well as the generation of gate signals for the semiconductor switching elements between the individual battery modules can be generated using appropriate modulation/control methods. The generation of the switching signals for the semiconductor switching elements between the battery modules can be selected in such a way that in the ideal case the switching signals only change at low frequency and thus cause low switching losses. This can be seen, for example, in the allocation of battery module 12 in the previously shown
(113) In view of the existing advantage that individual battery modules can also be used to provide a constant DC voltage with the proposed topology, battery module 12 in
(114) As mentioned before, the module matrix does not have to be limited to one level, but can be extended to several levels.
(115) Within the different battery modules, different switching topologies of the battery cells 46 can also be realized. A wide variety of topology variants can be implemented with p parallel-connected battery cells or battery strings and m serial-connected battery cells.
(116) Around the battery module 10 there are four external semiconductor switching elements S.sub.e1, S.sub.e2, S.sub.e3, S.sub.e4 for combination/connection with other battery modules. The semiconductor switching elements S.sub.b1, S.sub.b2, S.sub.b3, S.sub.b4 within the battery module additionally allow the connection or disconnection of individual strings from each other as well as the possibility of conducting current from each of the external semiconductor switching elements S.sub.e1, S.sub.e2, S.sub.e3, S.sub.e4 through the battery module to any other of these four semiconductor switching elements.
(117)
(118) The printed circuit board 170 provides contact surfaces 176, 178 as connecting contacts for contacting the potential connections 42, 44 of the galvanic cell 12. Furthermore, the printed circuit board 170 provides further contact surfaces to which the cell connectors 34, 36, 38, 40, 212, 214 are connected. The cell connectors 34, 36, 38, 40, 212, 214 are located on the housing cover 174, so that the battery cell 200 can be electrically contacted in the intended way.
(119) In the present case, it is provided that the potential connections 42, 44 of the galvanic cell 12 are pressed against the contact surfaces 176, 178 of the printed circuit board 170 by a spring force in order to establish the electrical contact. In alternative embodiments, another electrical connection can of course be provided here, for example by means of a screw or plug connection or the like. In this embodiment, the galvanic cell 12 is integrated with the circuit board 170 and arranged in the cell housing 180 of the battery cell 200.
(120)
(121) In principle, it can naturally also be provided in an alternative embodiment that a cell housing is provided, which covers at least the printed circuit board 170 and provides the cell connectors 34, 36, 38, 40, 212, 214. Furthermore, in a further alternative embodiment, the cell housing can also provide the connection contacts for the galvanic cell 12 as well as fastening elements, so that the galvanic cell 12 can be connected to the cell housing. For this purpose, the connecting contacts can be designed as screw terminals, for example, by means of which the potential connections 42, 44 of galvanic cell 12 can be electrically contacted. At the same time, a mechanical connection can also be achieved in this way. In addition, a mechanical connection can also be provided in the form of a clip connection, a clamping yoke and/or the like. Of course, these embodiments can also be combined with each other in almost any combination.
(122) The embodiments serve exclusively to explain the invention and are not intended to limit it.