Module for a battery, battery comprising the module, device comprising the battery, method for operating the module

Abstract

A module (101) for a battery, wherein the module (101) comprises at least one battery cell (104) in a series connection and a control unit (110) configured to operate the module (101) in a first state to determine the capacity of the module (101) during a discharge-charge cycle of the module (101) and to determine the capacity in the first state as a function of a current measurement in the series connection, and wherein the control unit (110) is configured to operate the module (101) in a second state outside of a discharge-charge cycle of the module (101) and to determine the capacity in the second state as a function of an open-circuit voltage across the series connection, in particular independently of the current measurement in the series connection. A battery comprising the module, a device comprising the battery, and a method for operating the module.

Description

[0001] The invention relates to a module for a battery, a battery comprising the module, a device comprising the battery, and a method for operating the module.

[0002] DE 10 2021 130 314 A1 discloses a method for event-driven initiation of measurements for determining the capacity of a battery. The cumulative current draw from the battery is measured during normal use. A battery module comprises at least one battery cell between two terminals of the module. A control system is configured to operate the module in its first state during a discharge-charge cycle to determine the module's capacity, and to determine the capacity in this first state based on a current measurement in a series circuit.

[0003] US 6 034 506 A discloses a battery for a satellite, comprising several battery cells and a circuit, wherein the circuit can bypass anomalous battery cells and thereby prevent overcharging.

[0004] A module for a battery, in particular a DC battery or a high-voltage battery, provides that the module includes at least one battery cell between two terminals of the module, wherein the module includes a first switch and a second switch, wherein the at least one battery cell and the first switch are arranged in series between the terminals, wherein the second switch is arranged in parallel to the series connection between the terminals, wherein the module includes a control unit configured to establish the electrical connection via the first switch and to disconnect the electrical connection via the second switch in a first state of the module, and to disconnect the electrical connection via the first switch and to establish an electrical connection via the second switch in a second state of the module, wherein the control unit is configuredThe module is designed to operate in the first state to determine the module's capacity during a discharge-charge cycle, determining the capacity in the first state based on a current measurement in the series circuit. The control system is also designed to operate the module in the second state to determine the capacity outside of a discharge-charge cycle, determining the capacity in the second state based on an open-circuit voltage across the series circuit, specifically independent of the current measurement in the series circuit. The module is a battery module that can be individually switched on and off for capacity determination. This makes it possible to determine the actual available capacity of a single module without requiring all battery modules to undergo a discharge-charge cycle simultaneously.

[0005] It is intended that the control system is designed to recognize the second state of the module as the target state depending on at least one of the following characteristics: temperature of the module, state of charge of the module, age of the module, number of cycles of use of the module, number of charging and / or discharging processes of the module, detected defect of the module, voltage to be supplied by the battery, current to be supplied by the battery, and to switch the module into the recognized target state by switching the switches of the module.

[0006] The control system is designed to recognize the second state of the module as the target state if the temperature of the module, and / or the temperature of at least one battery cell of the module, or the age of the module, or the number of cycles of use of the module, or the number of charging and / or discharging operations of the module, is greater than a predetermined threshold, and otherwise to recognize the first state of the module as the target state.

[0007] The control system is designed to recognize the second state of the module as the target state when a defect in the module is detected, and otherwise to recognize the first state of the module as the target state.

[0008] The control system is designed to recognize the second state of the module as the target state if the charge level of the module is lower than the charge level of another module, and otherwise to recognize the first state of the module as the target state.

[0009] Battery, wherein the battery comprises several modules, in particular in a series connection or in a parallel connection of several series connections.

[0010] Device, in particular satellite or vehicle, wherein the device includes the battery.

[0011] A method for operating a battery module, wherein the module comprises at least one battery cell in a series connection, wherein, to determine the module's capacity during a discharge-charge cycle, the module is operated in a first state and, in the first state, the capacity is determined as a function of a current measurement in the series connection, and wherein, to determine the module's capacity outside of a discharge-charge cycle, the module is operated in a second state and, in the second state, the capacity is determined as a function of an open-circuit voltage across the series connection, in particular independently of the current measurement in the series connection. This allows the module's discharge-charge cycle to be performed selectively for the module or the other module.

[0012] It is intended that the first state or the second state of the module is recognized as the target state and the module is switched to the received target state by switching the module's switches.

[0013] It is intended that in the process the second state or the first state of the module is recognized as the target state depending on at least one of the characteristics: temperature of the module, state of charge of the module, age of the module, number of cycles of use of the module, number of charging and / or discharging processes of the module, detected defect of the module, voltage to be supplied by the battery, current to be supplied by the battery.

[0014] The procedure provides that the second state of the module is recognized as the target state if the temperature of the module, or the age of the module, or the number of cycles of use of the module, or the number of charging and / or discharging processes of the module, is greater than a predetermined threshold, and otherwise the first state of the module is recognized as the target state.

[0015] The procedure stipulates that, in the event of a detected defect in the module, the second state of the module is recognized as the target state, and otherwise the first state of the module is recognized as the target state.

[0016] The procedure stipulates that the second state of the module will be recognized as the target state if the module's charge level is lower than that of another module, and otherwise the first state of the module will be recognized as the target state.

[0017] Further advantageous embodiments can be found in the following description and the drawing. The drawing shows: Fig. 1 a schematic representation of a module of a DC battery, Fig. 2 a part of a series circuit of modules, Fig. Figure 3 shows a flowchart with steps of a procedure for operating the DC battery.

[0018] Fig. Figure 1 schematically represents module 101 of a DC battery.

[0019] Module 101 has a terminal 102 for a negative potential and a terminal 103 for a positive potential. Module 101 comprises several battery cells 104, which are connected to terminal 102 for the negative potential via a shunt 105 and to terminal 103 for the positive potential via a fuse 106. The use of a shunt 105 is one exemplary embodiment of a current measuring device. A current measuring device based on Hall effect sensors or another component may also be provided. A fuse 105 is also one exemplary embodiment. Module 101 can also be implemented without the fuse. The components can also be arranged in a series circuit in a different order.

[0020] Between the terminal 103 for the positive potential and the battery cells 104, in particular between the fuse 106 and the battery cells 104, a first switch 107, e.g. a MOSFET, is arranged, which is configured to establish or break an electrical connection between the battery cells 104 and the terminal 103 for the positive potential.

[0021] In the illustrated example with a single MOSFET, interruption is possible for discharge, but charging cannot be interrupted due to the body diode. To also interrupt charging, two MOSFETs can be connected opposite to each other instead of the first switch 107, such that the forward direction of each body diode is directed towards the center of both MOSFETs, or the forward direction of both body diodes is directed outwards.

[0022] A second switch 108, e.g., a MOSFET, is arranged between terminal 103 for the positive potential and terminal 102 for the negative potential. This switch is configured to establish or break an electrical connection between terminal 103 for the positive potential and terminal 102 for the negative potential. In this example, the shunt 105 is arranged between the second switch 108 and the battery cells 104.

[0023] Module 101 includes the first switch 107 and the second switch 108.

[0024] Module 101 includes a controller 110. The controller 110 is configured to detect the potential between the shunt 105 and the second switch 108. The controller 110 is also configured to detect the potential between the individual battery cells 104 and the total potential provided by the battery cells 104. In this example, the total potential provided by the battery cells 104 ranges between 10V and 18V, depending on the cells and their chemistry.

[0025] In this example, one connection for supplying power to the controller 110 is electrically connected to connection 102 for the negative potential. Another connection for supplying power to the controller is connected to connection 111 for a supply voltage, e.g., 12V.

[0026] The controller 110 is configured, for example, to determine the capacity of module 101 based on the detected potentials when module 101 is bypassed (i.e., unloaded) and also contains relaxed battery cells 104. The controller 110 is also configured, for example, to determine the state of charge (SOC) based on the open-circuit voltage (OCV) when module 101 is unloaded (i.e., bypassed) and also contains relaxed battery cells 104. The controller 110 is further configured, for example, to determine the SOC based on the OCV voltage of the lowest cell voltage and the temperature of module 101, in particular the cell temperature of the battery cell 104 with the lowest cell voltage. In the simplest case, this means that the controller 110 is configured to perform an absolute determination of these values ​​at system startup.

[0027] The controller 110 is configured to account for relative changes when the module 101 is under load, i.e., not bypassed. Under load, i.e., during charging or discharging, the controller 110 is configured, for example, to detect the relative change via current measurement, specifically via Coulomb counting. For Coulomb counting, the current measuring device, e.g., the shunt 106, is used for current measurement.

[0028] Module 101 is cooled by a cooling system 111. For example, module 101 includes part of the cooling system 111, e.g., a cooling channel. For example, the cooling system 111, e.g., the cooling channel, is located outside module 101.

[0029] The control unit 110 is designed to control the first switch 107 and the second switch 108.

[0030] The control unit 110 is configured, for example, to switch module 101 into a first state by switching the switches of module 101. In the first state, the electrical connection is established via the first switch 107 and the electrical connection is broken via the second switch 108.

[0031] The control unit 110 is configured, for example, to switch module 101 into a second state by switching the switches of module 101. In the second state, the electrical connection via the first switch 107 is broken and the electrical connection via the second switch 108 is established.

[0032] The controller 110 is configured to operate module 101 to determine its capacity using the overcurrent protection (OCP) in the first state and to determine its capacity during the discharge-charge cycle in the second state. In the first state, the first switch 107 is conductive. The state of charge (SOC) is determined during operation of module 101 in the first state, e.g., during system startup, via the OCP. In the second state, the second switch 108 is conductive. The SOC is determined during operation of module 101 in the second state, e.g., via colorimetric counting.

[0033] This means that the controller 110 is configured to operate the module 101 in the first state to determine the capacity of the module 101 outside of a discharge-charge cycle of the module 101, and in the first state to determine the capacity depending on the current measurement in the series circuit.

[0034] This means that the controller 110 is configured to operate the module 101 in the second state to determine the capacity of the module 101 in the discharge-charge cycle of the module 101, and in the second state to determine the capacity depending on an open-circuit voltage across the series circuit, in particular independently of the current measurement in the series circuit.

[0035] The controller 110 is configured to operate the module 101 in either the first or second state, depending on a target state. The target state is, for example, the first state or the second state. The controller 110 is configured to recognize the target state.

[0036] The control unit 110 is designed to switch the module 101 into the first state or the second state by switching the switches of the module 101, depending on the desired state.

[0037] In one example, the controller 110 is trained to detect whether the module 101 is overheating or not.

[0038] For example, the controller 110 includes a temperature sensor configured to detect the temperature of module 101. For example, the controller 110 includes a temperature model configured to detect the temperature of module 101. It may be provided that external temperature sensors are connected which measure the cell temperature, e.g., at the surface of the battery cells 104.

[0039] The controller 110 is, for example, designed to receive a signal indicating whether the module 101 is overheating or not.

[0040] Fig. Figure 2 schematically represents part of a series connection of modules 101. In the example, two modules 101 of the series connection are shown.

[0041] The cooling unit 111 is designed to cool the modules 101 in series.

[0042] It is possible to arrange several series-connected modules 101 in parallel. It is possible to provide a cooling system 111 to cool the modules 101 in the parallel connection. It is possible to provide one cooling system 111 for each series-connected module in the parallel connection.

[0043] If temperature fluctuations are expected, the cooling system 111 is configured to meet the maximum cooling requirement. By being able to disable and thus cool individual modules 101 that overheat, the cooling system 111 can be configured for a lower cooling requirement than a conventional, hardwired DC battery.

[0044] Modules 101 can be modules 101 of a high-voltage battery.

[0045] In Fig.Figure 3 shows a flowchart of a procedure for operating the DC battery. The procedure is carried out, for example, for each module 101 of the DC battery.

[0046] The procedure includes a step 301.

[0047] In step 301, the target state for module 101 is specified.

[0048] The first state will be specified as the target state if the module 101 itself is to perform a discharge-charge cycle.

[0049] For example, the second state is specified as the target state when another module 101 of the battery is to perform a discharge-charge cycle.

[0050] For example, the second state is set as the target state if module 101 overheats. The second or first state is set as the target state depending on the temperature provided by the temperature sensor or the temperature model. For example, the second state is set as the target state if the temperature exceeds a predefined threshold. Otherwise, the first state of module 101 is set as the target state.

[0051] Then, step 302 is executed.

[0052] In step 302, module 101 is switched to the desired state by switching the first switch 107 and the second switch 108.

[0053] For example, the switches are controlled depending on the desired state.

[0054] In the second state, the first switch 107 is activated to interrupt the electrical connection between the battery cells 104 of the module and the terminal 103 for the positive potential, and the second switch 108 is activated to establish an electrical connection between the terminal 102 for the negative potential and the terminal 103 for the positive potential.

[0055] In the first state, the first switch 107 is activated to establish the electrical connection between the battery cells 104 of the module and the terminal 103 for the positive potential, and the second switch 108 is activated to interrupt the electrical connection between the terminal 102 for the negative potential and the terminal 103 for the positive potential.

[0056] This means that, to determine the capacity of module 101 in the discharge-charge cycle of module 101, module 101 is switched to the first state by switching the switches of module 101.

[0057] In the first state, the capacitance is determined depending on the current measurement in the series circuit.

[0058] This means that, in order to determine the capacity of module 101 outside of the discharge-charge cycle of module 101, module 101 is switched to the second state by switching the switches of module 101.

[0059] In the second state, the capacitance is determined depending on the open-circuit voltage across the series circuit, in particular independently of the current measurement in the series circuit.

[0060] This means that if module 101 overheats, the module will be switched to the second state by switching the switches.

[0061] This means that if module 101 is not overheated, module 101 will be switched to the first state by switching the switches.

[0062] This means that module 101 is bypassed, i.e., not used, if another module is supposed to perform the discharge-charge cycle or if module 101 itself is overheating. This means that module 101 is not bypassed, i.e., not used, if module 101 itself is supposed to perform the discharge-charge cycle or if module 101 itself is not overheating.

[0063] Step 301 is then executed.

[0064] For example, the second state or the first state is specified as the target state depending on one or a combination of two or more of the following characteristics: the temperature of module 101 and / or the temperature of at least one battery cell 104 of module 101, the charge level of module 101, the age of module 101, the number of cycles of using module 101, the number of charging and / or discharging cycles of module 101, a detected defect of module 101, voltage to be provided by the DC battery Current to be supplied by the DC battery.

[0065] It may be provided that a series connection comprises more modules 101 than are required to provide the total voltage to be supplied by the series connection. In this series connection, a rotation of the unused module 101, or of the module 101 or modules 101 that are used in place of the unused module 101, may be provided.

[0066] For example, for one module 101 with a lower state of charge than another module 101 in a series connection of the two modules, the second state is determined for module 101 and the first state is determined for the other module 101.

[0067] This ensures that the modules 101 are discharged evenly with regard to their state of charge.

[0068] For example, for module 101 in a series connection of modules for which a defect has been detected, the second state is determined. This allows the series connection to continue to be used without the defective module 101.

[0069] Temperature fluctuations can occur during the operation of the DC battery, e.g., in a satellite or in a non-rail-bound vehicle with rubber tires. If the temperature fluctuations and the requirement for modules 101 to provide the voltage or current to be supplied by the DC battery are predictable, it may be provided that the second state is defined as the target state for a number of modules 101 that are not required for supply.

[0070] The DC battery is designed to be charged and discharged. Charging can be done, for example, using photovoltaics. Charging can also be cyclical, depending particularly on the positions of satellites and the sun.

[0071] The number of charging and / or discharging processes is optimized, for example, by determining a frequency of the second state or the first state as the target state for a single module 101 with regard to the service life of the respective module 101.

[0072] The procedure can provide that the rotation for modules 101 from different series connections is applied accordingly from the parallel connection. This is provided, for example, when the voltages provided by the individual series connections differ by less than a predetermined threshold when one of the modules 101 from one of the series connections is bridged.

[0073] The procedure is carried out accordingly for modules 101 of the high-voltage battery.

Claims

[1] A module (101) for a battery, in particular a DC battery or a high-voltage battery, characterized bythat the module (101) comprises at least one battery cell (104) between two terminals (102, 103) of the module (101), wherein the module (101) comprises a first switch (107) and a second switch (108), wherein the at least one battery cell (104) and the first switch (107) are arranged in series between the terminals (102, 103), wherein the second switch (108) is arranged in parallel to the series connection between the terminals (102, 103), wherein the module (101) comprises a control (110) configured to establish the electrical connection via the first switch (107) and to disconnect the electrical connection via the second switch (108) in a first state of the module (101), and to disconnect an electrical connection via the first switch (107) and to establish an electrical connection via the second switch (108) in a second state of the module (101), wherein the control (110) is trained,to operate the module (101) in the first state for determining the capacity of the module (101) in a discharge-charge cycle of the module (101) and to determine the capacity in the first state depending on a current measurement in the series circuit, and wherein the control (110) is configured to operate the module (101) in the second state for determining the capacity of the module (101) outside of a discharge-charge cycle of the module (101) and to determine the capacity in the second state depending on an open-circuit voltage across the series circuit, in particular independently of the current measurement in the series circuit, wherein the control (110) is configured to define the first state or the second state of the module (101) as a target state depending on at least one of the characteristics: temperature of the module (101) and / or the temperature of at least one battery cell (104) of the module (101), state of charge of the module (101), age of the module (101), number of cycles of use of the module (101).The number of charging and / or discharging cycles of the module (101), the detected defect of the module (101), the voltage to be supplied by the battery, the current to be supplied by the battery, and the module (101) is switched into the detected target state by switching the switches of the module (101), wherein the control unit (110) is configured to determine the second state of the module (101). - to recognize as the target state if the temperature of the module (101), or the age of the module (101), or the number of cycles of use of the module (101), or the number of charging and / or discharging processes of the module (101), is greater than a predefined threshold, and otherwise to recognize the first state of the module (101) as the target state, or - to recognize the desired state if a defect of the module (101) is detected, and otherwise to recognize the first state of the module (101) as the desired state, or - to recognize as the target state if the charge state of module (101) is less than the charge state of another module (101), and otherwise to recognize the first state of module (101) as the target state. [2] Battery, characterized by , that the battery comprises several modules (101) according to claim 1, in particular in a series connection or in a parallel connection of several series connections. [3] Device, in particular satellite or vehicle, characterized by that the device comprises the battery according to claim 2. [4] Method for operating a module of a battery, characterized bythat the module (101) comprises at least one battery cell (104) in a series connection, wherein, to determine the capacity of the module (101) in a discharge-charge cycle of the module (101), it is operated in a first state and, in the first state, the capacity is determined as a function of a current measurement in the series connection (302), and wherein, to determine the capacity of the module (101) outside of a discharge-charge cycle of the module (101), the module (101) is operated in a second state and, in the second state, the capacity is determined as a function of an open-circuit voltage across the series connection, in particular independently of the current measurement in the series connection (302), wherein the first state or the second state of the module (101) is recognized as the target state and the module (101) is switched into the received target state by switching the switches of the module (101), and wherein - the second state or the first state of the module (101) depending on at least one of the characteristics: temperature of the module (101), state of charge of the module (101), age of the module (101), number of cycles of use of the module (101), number of charging and / or discharging operations of the module (101), detected defect of the module (101), voltage to be supplied by the battery, current to be supplied by the battery, is recognized as the target state, or - the second state of the module (101) is recognized as the target state if the temperature of the module (101), or the age of the module (101), or the number of cycles of use of the module (101), or the number of charging and / or discharging processes of the module (101), is greater than a predefined threshold, and otherwise the first state of the module (101) is recognized as the target state, or - the second state of the module (101) is recognized as the target state when a defect of the module (101) is detected, and otherwise the first state of the module (101) is recognized as the target state, or - the second state of the module (101) is recognized as the target state if the charge state of the module (101) is less than the charge state of another module (101), and otherwise the first state of the module (101) is recognized as the target state.

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