BATTERY HAVING AT LEAST TWO BATTERY CELLS, AND MOTOR VEHICLE

Abstract

A battery with at least two battery cells, which are connected by at least one electric connection element to one another, and a superordinate control device. Each of the battery cells is provided with at least one galvanic element, a battery cell housing for accommodating the galvanic element, at least one sensor device for detecting a physical and/or chemical feature of the battery cell, and a communication device for communicating with the superordinate device. The superordinate device is adapted to control an energy flow in at least one of the battery cells and/or from at least one of the battery cells as a function of the physical and/or chemical features of the battery cell. The invention further also relates to a motor vehicle with such a battery.

Claims

1-10. (canceled)

11. A battery, comprising: at least two battery cells, which are connected to each other by means of an electric connection element, and with a superordinate control device, wherein each of the battery cells is provided with at least one galvanic element, a battery cell housing for accommodating the galvanic element, at least one sensor device for detecting at least one physical and chemical feature of the battery cell and a communication device for communicating with the superordinate control device, wherein the superordinate control device is adapted to control as a function of the physical and chemical features of the battery cells an energy flow in at least one of the battery cells and from at least of the battery cells.

12. The battery according to claim 11, wherein each of the battery cells is provided with a storage device for storing the physical and chemical features of the battery cell and the superordinate cell is adapted to control the energy flow as a function of the stored physical and chemical features of the battery cells.

13. The battery according to claim 11, wherein the electric connection element is provided with at least one sensor device for detecting state variables of the electric connection element and a communication device for communicating with the superordinate control device, and the superordinate control device is adapted to control the energy flow as a function of the detected state variable.

14. The battery according to claim 11, wherein each of the battery cells is provided with at least one switching device by means of which an electrode of the galvanic element and a connection of the respective battery cell are electrically coupled and by means of which a current flow between the galvanic element and the connection of the respective battery cell can be controlled, and the superordinate control device is designed to control as energy flow the current flow between the electrode and the connection of at least one of the battery cells.

15. The battery according to claim 14, wherein at least one sensor device of each of the battery cells is provided with a temperature sensor for detecting a temperature and with a pressure sensor for detecting a pressure of the respective battery cell and the superordinate control device is adapted to control the current flow between the electrode and the connection of the respective battery cells as a function of the temperature and of the pressure of the respective battery cell.

16. The battery according to claim 14, wherein each of the battery cells is respectively provided with an evaluation device, which is adapted as a function of the detected physical and chemical features to determine the extent of the damage of the respective battery cell, wherein the superordinate control device and the evaluation device is adapted to control the current flow between the electrode and the connection of the respective battery cell as a function of the extent of damage to the respective battery cell.

17. The battery according to claim 15, wherein the at least one sensor device of each of the battery cells is designed to detect a charging state of the respective battery cell, wherein the superordinate control device is adapted to compare the charging states of the battery cells to one another and when a predetermined deviation limit for the charging state is exceeded, to control the charging states in order to match them.

18. The battery according to claim 17, wherein each of the battery cells is provided with a resistance element which is in particular thermally coupled to the battery cell housing, and the superordinate control device is adapted to electrically connect at least one battery cell for matching the charging states with the electrodes of the galvanic element of the respective battery cell when the predetermined deviation limit is exceeded.

19. The battery according to claim 17, wherein the at least two battery cells are connected in series by means of the electric connection element and at least one side wall of a first battery cell housing and at least one side wall of a second battery cell housing is provided with an electrically conductive material, and the superordinate control device is designed to control a capacitive energy transmission between the side walls of the battery cell housing when the predetermined deviation limit is exceeded so as to match the charging states.

Description

[0037] The invention will now be described in the following based on a preferred embodiment, as well as with reference to the attached FIGURE.

[0038] The single FIGURE shows a schematic representation of a battery with battery cells.

[0039] The embodiment described in the following is a preferred embodiment of the invention. However, the components of the embodiment that are described in the embodiment represent individual features of the invention which are independent of one another, wherein each of them also further develops the invention independently of each other and thus also individually, or in a combination that is different from the shown combination and that should be seen as a component of the invention. In addition, the described embodiment can be complemented also by other features of the invention that have been already described.

[0040] The FIGURE shows a battery 1, of which only five battery cells 2 are shown. Only the battery cell housings of the battery cells 2 are visible here. Inside the battery cell housing is arranged a respective galvanic element. The battery cells 2 are here connected via a respective electric connection element 3 designed in the form of a current rail to the battery 1. Here, the battery cells 2 are connected via the electric connection element 3 in series, wherein a respective connection 4 of a battery cell 2 is electrically connected to a negative connection 5 of an adjacent battery cell 2. In addition, the battery 1 is provided with a superordinate control device 6.

[0041] Each of the battery cells 1 is provided with at least one of the sensor devices 7, 8, 9 which are used to detect physical and/or chemical properties of the battery cells 2. In this case, the sensor device 7 is designed as a charging state sensor detecting a charging state of the respective battery cell 2, the sensor device 8 is designed as a temperature sensor detecting a temperature in the interior of the battery cell housing of the respective battery cell 2, and the sensor device 9 is designed as a pressure sensor detecting a pressure in the interior of the battery cell housing of the respective battery cell 2. The sensor devices 7, 8, 9 are here arranged within the battery cell housing of each battery cell 2.

[0042] Moreover, each of the battery cells 2 is provided with a communication device 10 in the form of a radio antenna. The battery cells 2 can communicate via the respective communication device 10 with the superordinate control device 6. The communication takes place as wireless communication, for example via WLAN or Bluetooth or the like. However, it can be also provided that each of the battery cells 2 communicates via a line 11 with the superordinate control device 6. For this purpose, the line 11 is connected for example with one of the connections 4, 5 to the battery cells 2. The line 11 can be a so-called Ethernet cable. The data can be thus transmitted in this manner between the superordinate control device 6 and the respective battery cell 2. The line 11 can be also a so called power line, wherein the data is transmitted through the power grid.

[0043] Each of the battery cells 2 is in this case also provided with a security function 19, by means of which it can be for example ensured that the energy storage device has been supplied by a so-called original manufacturer (OEM—original equipment manufacturer). Individual identification numbers, so-called IDs and other information can be electronically stored therein for each battery cell 2.

[0044] It can be also provided that each of the electric connection elements 3 is equipped with a sensor device 18 and with a communication device 12 for communicating with the superordinate control device 6. The data of the sensor device 18 of the electric connection element 3 can be transmitted by means of this communication device 12 to the superordinate control device 6. Such data can for example indicate a current that flows via the electric connection element 3 between the connections 4, 5 of two battery cells 2, or a temperature, or a mechanic deflection of the electric connection element 3.

[0045] The control device 6 is in this case designed to receive the transmitted data, which is to say the data of the sensor devices 7, 8, 9 and/or the data relating to the electric connection elements 3 so as to control as a function of this data the energy flow from at least one of the battery cells and/or in one of the battery cells 2. It can be also provided that the superordinate control device communicates with a battery management system, not shown here, for example via a bus connection 20.

[0046] It can be further also provided that each of the battery cells 2 is equipped with an evaluation device which itself is designed to carry out the evaluation of the data of the sensor devices 7, 8, 9. It can be furthermore also provided that calculations are carried out by the superordinate device 6 and only the results are transmitted to the evaluation device of the respective battery cell 2.

[0047] For example an impedance analysis or an impedance microscopy can be carried out by means of the evaluation device for each of the battery cells 2 and a statement can thus be obtained for example about the internal resistance of each of the battery cells 2. So for example, the energy flow can be adapted to the inner resistance of the respective battery cell 2 in order to ensure in this manner an equal load on all of the battery cells 2 of the battery 1. It is also possible to provide information for a charging column, which is to say a device for providing charging energy, in an active manner about the actual state, for example about the state of health (SoH) of each of the battery cells 2. For example, the charging can be dynamically adapted to the state of the respective battery cell 2 and for example actively switched off in case of a critical state of the battery cell 2.

[0048] In order to control the flow of energy, each of the battery cells 2 may be provided with a switching device 13. The switching device 13 can have an electronic switching element and/or a relay. A current flow is controlled by means of the switching device, in particular between the galvanic element in the battery cell housing and the connections 4, 5 of the same battery cell 2, wherein a control signal is provided for instance by the superordinate control device 6, for instance a control voltage. In particular, a current flow can be limited or interrupted by means of the switching device 13 between the galvanic element and the connections 4, 5. The switching device 13 can therefore fulfill the function of a fuse that is per se known.

[0049] The superordinate control device 6 is preferably designed to control a current flow as the energy flow between the galvanic element and the connections 4, 5 of at least one of the battery cells 2 by means of a switching device 13. The current flow can then be interrupted or blocked, for example by the switching device 13 that is controlled by the superordinate control device 6, when a current load of this battery cell 2 appears to be dangerous. This can occur, for example, when it was detected by the sensor device 9 that the pressure in the battery cell housing has exceeded a threshold value predetermined for a pressure and this increased pressure value was communicated to the superordinate control device 6, for example via the communication device 10 of the battery cell 2. After that, the superordinate control device 6 can control the switching device 13 in order to block the current flow. The current flow of a battery cell 2 can be also limited if the battery cell 2 for example displays a state of health (SoH) which indicates aging or damage of the battery cell 2.

[0050] The switching device 13 can be switched on by the evaluation device of each of the respective battery cells 2, in particular depending on the data sensor devices 7, 8, 9 of the respective battery cells 2.

[0051] In the case of the battery 1, several battery cells 2 can be also connected to one battery module and multiple battery modules can be connected together. According to an embodiment of the switching device 13 which is realized as a power semiconductor element, with this embodiment it can be in addition ensured that the battery 1 can compensate for a resulting total resistance, which is dependent on the respective length and on the linking of the current rail to the respective connection 4, 5, as well as on the transition between the battery modules. In other words, this means that an internal resistance of each of the battery cells 2 can be dynamically adjusted by means of the switching device 13. The battery cells are thus subjected to an equal load as a result of a total resistance compensation and they will thus also age equally in the long term.

[0052] An energy flow between the battery cells 2 can be also controlled to create an equal charging state of the battery cells 2. When for example a first charging state of one of the battery cells 2 was detected by one of the sensor devices 7 and another charging state of another of the battery cells 2 was detected by the sensor device 7 which is greater compared to the first charging state, the superordinate control device 6 can determine a deviation between the first and the second charging state. When this deviation exceeds a predetermined threshold value of the deviation, the superordinate control device 6 can carry out a balancing or a compensation of the charging state.

[0053] For this purpose, the battery cells can be discharged with the second charging state, for example via a resistance element, not shown here. The superordinate device 6 can for this purpose connect the resistance element, for example by means of a switching element, so that the electrodes of the galvanic element of the battery cell 2 are connected with the second charging state until the second charging state is matched to the first charging state. This is referred to as passive or dissipative balancing.

[0054] The superordinate control device 6 can also carry out active balancing, so that it controls the energy flow from the battery cell 2 occurring with the second charging state with the first charging state. Here, the electric energy is capacitively transmitted from the battery cell 2 with the second charging state to the battery cell 2 with the first charging state. For this purpose, the side walls 14 of the battery cell housing of the battery cells 2 are provided with an electrically conductive material 15. It can be also provided that the battery cell housing is already manufactured from the electrically conductive material 15, for example aluminum. In this manner, the electrodes of the plate capacitor are formed by means of two side walls 14 which are facing each other. In this case, the side walls 13 form the electrodes of the plate capacitor and a an insulating material 16 arranged between the side walls 14 forms a dielectric of the plate capacitor. A capacitive energy transmission 17 can thus be obtained by means of this plate capacitor between two adjacent battery cells 2. In this case, the capacitive energy of the battery cells can also occur via a plurality of the battery cells 2. With the energy transfer from a battery cell 2 to an adjacent battery cells 2, it is therefore not required to first store the energy to be distributed in the respective battery cell 2 and then to remove it again and thus possibly to operate the battery cell 2 outside of the limits set by the chemistry of the battery cell. As a result of the interlinked plate capacitor arrangement, there is the option to transmit the energy amount to be distributed directly to the next battery cell 2 in a dynamic and targeted manner, which is to say without storing it in a battery cell 2.