Charging device and method for charging an electrical energy store

Abstract

The invention relates to a charging device (1) and a method for charging an electrical energy store (2), wherein the charging device (1) has a control unit (12) and a regulating unit (9), wherein the charging device (1) is set up to charge the electrical energy store (2) to a specified state of charge within a predefined charging time and for this purpose to set a charging current and a side reaction current of the electrical energy store (2).

Description

Technical Field

[0001] This invention relates to a charging device and method for charging an energy storage device. Background Technology

[0002] US 2016 / 0336765 A1 discloses a battery controller that generates a battery model and uses measurement data from a single battery cell for this purpose. Summary of the Invention

[0003] Regarding the charging device for an energy storage device, the core of the present invention is that the charging device has a control unit and an adjustment unit, wherein the charging device is configured to charge the energy storage device to a predetermined state of charge within a predetermined charging time, and to this end, the charging current and the side reaction current of the energy storage device are set.

[0004] The background of this invention is that the control unit and the regulating unit can operate simultaneously. The charging current is controlled by the control unit so that the energy storage device can be charged to a predetermined state of charge within a predetermined charging time. Simultaneously, the regulating unit uses the current state parameters of the energy storage device to regulate the charging current, thereby minimizing the aging of the energy storage device.

[0005] Advantageously, the charging device can quickly adapt the charging current to the dynamic state changes of the energy storage device. Therefore, it can shorten the charging time of the energy storage device or achieve fast charging while reducing aging.

[0006] Further advantageous embodiments of the invention are the subject of the dependent claims.

[0007] According to an advantageous design, the charging device has an analysis unit with at least one connector for a sensor used in the energy storage device. Specifically, the analysis unit includes a state-of-charge analysis device and an aging analysis device. Thus, the operating parameters of the energy storage device can be analyzed by the analysis unit and adjusted by the charging device.

[0008] Advantageously, the connector is suitable for temperature sensors and / or voltage sensors.

[0009] Advantageously, the state of charge (SCC) analyzer is connected to the control unit via a signal transmission line. Therefore, the control unit can analyze the SCC, and the charging current can be adapted to the current SCC.

[0010] Furthermore, it is advantageous that the aging analysis device is connected to the regulating unit via a signal transmission method. Therefore, the aging state can be analyzed by the regulating unit, and the charging current can be adjusted in such a way that further aging of the energy storage device can be minimized.

[0011] Advantageously, the control unit is configured to control the first charging current and the first secondary reaction current such that the energy storage device is charged to a predetermined state of charge within a predetermined charging time.

[0012] Advantageously, the regulating unit is configured to adjust the third charging current in such a way that the second reactive current of the energy storage device is minimized. Therefore, the aging of the energy storage device can be reduced.

[0013] Furthermore, it is advantageous that the charging device has a summing device arranged on one hand between the control unit and the regulating unit, and on the other hand between the control unit and the output connector of the charging device. Specifically, the summing device is configured to add a first or second charging current from the control unit to a third charging current from the regulating unit, and generate a fourth charging current as a sum. Therefore, when only the first or second charging current is available, it can be used for charging. When the third charging current is not equal to zero, the fourth charging current, or the sum of the third and second or first charging currents, can be used for charging.

[0014] Advantageously, the charging device has a low-pass filter arranged between the control unit and the summing device, wherein the low-pass filter is configured to smooth the first charging current into a second charging current.

[0015] Advantageously, the charging device has a comparison device arranged on one hand between the control unit and the aging analysis device, and on the other hand between the control unit and the summing device. Specifically, the comparison device is configured to compare a first secondary reaction current with a second secondary reaction current, and particularly to calculate the difference between the first and second secondary reaction currents. Thus, the secondary reaction current induced by the control unit can be compared with the current secondary reaction current in the energy storage device, and the aging of the energy storage device can be adjusted by the adjustment unit. If the first and second secondary reaction currents are the same magnitude, then no third charging current is determined, or the third charging current is equal to zero.

[0016] The core of this invention lies in the fact that the method has a control method step and an adjustment method step, which operate in parallel in time, wherein the energy storage device is charged to a predetermined state of charge within a predetermined charging time and the charging current and side reaction current of the energy storage device are set for this purpose.

[0017] The background of this invention lies in the simultaneous operation of regulation and control. Therefore, the charging process can be quickly adapted to the dynamic changes in the energy storage device.

[0018] Advantageously, it can shorten the charging time of the energy storage device or enable fast charging while reducing aging.

[0019] According to an advantageous design, the current state of charge and the current aging state and / or the second secondary reaction current are obtained from the sensor data of the energy storage device, wherein a first charging current and a first secondary reaction current are generated by means of the energy storage device model using the current state of charge, the specified state of charge, and the available charging time.

[0020] Advantageously, a third charging current is generated by comparing the first and second auxiliary reaction currents, particularly where the third charging current is zero when the first and second auxiliary reaction currents have the same value, and / or where the first and second auxiliary reaction currents have different values. This determination of the third charging current minimizes the aging of the energy storage device. The third charging current is then added to the second charging current to generate a fourth charging current, particularly where the fourth charging current has the same value as the second charging current when the third charging current is zero. The energy storage device is charged with either the second or fourth charging current, particularly where the second charging current is used when the third charging current is zero. Advantageously, the second charging current is available once the charging process is initiated. The third charging current is available only with a delay because the adjustment method steps are more time-consuming than the control method steps. Once the third charging current is available, the fourth charging current can be generated and the energy storage device charged with the fourth charging current, thereby reducing the aging of the energy storage device.

[0021] Wherever meaningful, the above design and improvement schemes can be arbitrarily combined with each other. Other feasible design schemes, improvements, and implementations of the present invention also include combinations of features not explicitly mentioned above or described below with respect to embodiments. In particular, those skilled in the art will also add various aspects as improvements or supplements to the corresponding basic form of the present invention. Attached Figure Description

[0022] In the following sections, the invention is illustrated by way of embodiments from which further features of the invention can be derived; however, the invention is not limited in scope to these features. These embodiments are shown in the accompanying drawings.

[0023] in:

[0024] Figure 1 A schematic diagram of a method according to the invention is shown, which is used to charge an energy storage device 2 by means of a charging device 1 according to the invention. Detailed Implementation

[0025] exist Figure 1 The diagram schematically illustrates a charging device 1 and an energy storage device 2 according to the present invention.

[0026] Charging device 1 has:

[0027] - Control unit 12, the control unit having a first control device 3 and a second control device 11,

[0028] - Low-pass filter 4,

[0029] - Analysis unit 5, which includes a state of charge analysis device 6 and an aging analysis device 7.

[0030] - Summation apparatus 8,

[0031] - Adjustment device 9, and

[0032] - Comparison device 10.

[0033] Analysis unit 5 is connected to energy storage device 2 via signal transmission and is configured to receive sensor signals from sensors in energy storage device 2, particularly a temperature sensor and at least one single-cell voltage sensor. Analysis unit 5 is configured to analyze the sensor signals from energy storage device 2, particularly the temperature T and at least one single-cell voltage Uc, and thereby determine the state parameters of energy storage device 2 by means of a fourth charging current I4. For this purpose, analysis unit 5 has at least one state-of-charge analysis device 6 and an aging analysis device 7. Preferably, analysis unit 7 is configured to determine the state parameters of energy storage device from the sensor signals by means of at least one energy storage device model.

[0034] The state of charge (SCC) analyzer 6 is configured to determine the current SCC of the energy storage device 2. The SCC analyzer 6 is connected to the control unit 12, particularly the first control unit 3, and the second control unit 11 via signal transmission. The SCC analyzer 6 is configured to send the current SCC to the control unit 12, particularly to the first control unit 3, and to the second control unit 11.

[0035] The aging analysis device 7 is configured to determine the aging state of the energy storage device 2 and the resulting second auxiliary reaction current J2. The aging analysis device 7 is connected to the comparison device 10 in a signal-transmitting manner. The aging analysis device 7 is configured to send the second auxiliary reaction current J2 to the comparison device 10.

[0036] Here, the side reaction current is the current that occurs during charging due to the aging of the single cell caused by side reactions in the single cell of the energy storage device 2, such as dendrite growth on the anode or electrolyte deposition.

[0037] The control unit 12 is configured to control a first charging current I1 for charging the energy storage 2 and the resulting first reactive current J1, by means of the state of charge of the energy storage 2, preferably by means of a model of the energy storage 2. This model of the energy storage 2 allows the first charging current I1 and the first reactive current J1 to be controlled in such a way that the current state of charge, the predetermined state of charge to be achieved, and the available charging time are taken into account, thereby minimizing the aging of the energy storage.

[0038] The control unit 12 has a first control device 3 and a second control device 11.

[0039] The first control device 3 has a memory unit in which charging current curves for the energy storage device 2 are stored. The first control device 3 is configured to select a suitable charging current curve depending on the state of charge of the energy storage device 2.

[0040] The first control device 3 is connected to the state of charge analysis device 6 via a signal transmission ground. The first control device 3 is configured to control the first charging current I1 by means of the state of charge, so as to charge the energy storage device 2 to a predetermined state of charge within a charging time. The first control device 3 is electrically connected to the low-pass filter 4. The first control device 3 is configured to direct the first charging current I1 to the low-pass filter 4.

[0041] The low-pass filter 4 electrically connects the first control device 3 and the summing device 8. The low-pass filter 4 is configured to smooth the first charging current I1 and convert it into a second charging current I2, and guide the second charging current I2 to the summing device 8.

[0042] The second control device 11 is connected to the state of charge analysis device 6 via a signal transmission ground. The second control device 11 is configured to control the first secondary reaction current J1 by means of the state of charge and by means of a predetermined state of charge to be achieved through charging within a charging time. The second control device 11 is also connected to the comparison device 10 via a signal transmission ground. The second control device 11 is configured to send the first secondary reaction current J1 to the comparison device 10.

[0043] The comparison device 10 is arranged between the second control device 11 and the adjustment unit 9. The comparison device 10 is also arranged between the aging analysis device 7 and the adjustment unit 9. The comparison device 10 is configured to receive and compare a first sub-reaction current J1 and a second sub-reaction current, particularly a differential sub-reaction current configured as the difference between the first sub-reaction current J1 and the second sub-reaction current J2. The comparison result between the first sub-reaction current J1 and the second sub-reaction current J2 is sent to the adjustment unit 9.

[0044] An adjustment unit 9 is arranged between the summing device 8 and the comparison device 10. The adjustment unit 9 is configured to generate a third charging current I3 for charging the energy storage device 2, which induces a side reaction current in the energy storage device 2 corresponding to a minimum degree of aging of the energy storage device 2. The adjustment unit 9 is electrically connected to the summing device 8 and configured to direct the third charging current I3 to the summing device 8.

[0045] The adjustment unit 9 uses an adjustment method based on frequency and employing the fractional derivative order as a parameter, particularly the CRONE method. Here, a numerical linear model of a nonlinear energy storage model is used.

[0046] The summing device 8 acts as a node between the low-pass filter 4 and the adjustment unit 9 on one side and between the energy storage device 2 and the analysis unit 5 on the other side. The summing device 8 is configured to add the second charging current I2 and the third charging current I3 together, thereby generating a fourth charging current I4, which is used to charge the energy storage device 2. For this purpose, the summing device 8 is electrically connected to the energy storage device 2. Furthermore, the summing device 8 is signal-transmittingly connected to the analysis unit 5 so as to send the fourth charging current I4 to the analysis unit 5.

[0047] The method according to the invention for charging the energy storage device 2 has a control method step and an adjustment method step, which operate simultaneously or in parallel in time.

[0048] In the first method step, the current state of charge and the current aging state of the energy storage 2 are determined, and the current aging state causes the current second secondary reaction current J2 in the energy storage 2.

[0049] In the first control method step, a first charging current I1 and a first auxiliary reaction current J1 are generated using the model of the energy storage 2, taking into account the current state of charge, the predetermined state of charge to be achieved by charging, and the available charging time. Here, the first charging current I1 and the first auxiliary reaction current J1 are selected in such a way that the aging of the energy storage 2 is minimized.

[0050] In the second control method step, the first charging current I1 is smoothed into the second charging current I2.

[0051] In the first adjustment method step, the first auxiliary reaction current J1 is compared with the second auxiliary reaction current J2, and a third charging current I3 is generated. Here, when the first auxiliary reaction current J1 has the same value as the second auxiliary reaction current J2, the third charging current I3 is equal to zero. When the first auxiliary reaction current J1 and the second auxiliary reaction current J2 have different values, the third charging current is determined in such a way that the aging of the energy storage device 2 is minimized.

[0052] In the second adjustment method step, the third charging current I3 and the second charging current I2 are added together and summed to generate a fourth charging current I4. Here, when the third charging current I3 is equal to zero, the fourth charging current I4 has the same value as the second charging current I2.

[0053] In the second method step, the energy storage 2 is charged with a fourth charging current I4.

[0054] Thereafter, the method continues with the first method steps.

[0055] Here, energy storage is understood as a rechargeable energy storage device, particularly an electrochemical energy storage single cell and / or an energy storage module and / or an energy storage group having at least one electrochemical energy storage single cell. The energy storage single cell can be designed as a lithium-based battery single cell, particularly a lithium-ion battery single cell. Alternatively, the energy storage single cell can be designed as a lithium polymer battery single cell, a nickel-metal hydride battery single cell, a lead-acid battery single cell, a lithium-air battery single cell, or a lithium-sulfur battery single cell.

Claims

1. A charging device (1) for an energy storage device (2), Its features are, The charging device (1) has a control unit (12) and an adjustment unit (9). The charging device (1) is configured to charge the energy storage device (2) to a predetermined state of charge within a pre-given charging time, and for this purpose, the charging current and the side reaction current of the energy storage device (2) are configured. The charging device (1) has an analysis unit (5) with at least one connector for a sensor for the energy storage device (2). The analysis unit (5) has a state of charge analysis device (6) and an aging analysis device (7). The state of charge analysis device (6) is configured to send the current state of charge to a control unit (12). The control unit (12) is configured to control a first charging current (I1) for charging the energy storage device (2) and a first secondary reaction current (J1) resulting therefrom, by means of the state of charge of the energy storage device (2) and by means of a model of the energy storage device (2).

2. The charging device (1) according to claim 1. Its features are, The state of charge analysis device (6) is connected to the control unit (12) via a signal transmission.

3. The charging device (1) according to claim 1 or 2. Its features are, The aging analysis device (7) is connected to the adjustment unit (9) via a signal transmission method.

4. The charging device (1) according to claim 1 or 2. Its features are, The control unit (12) is configured to control the first charging current (I1) and the first secondary reaction current (J1) so that the energy storage (2) is charged to a predetermined state of charge within a predetermined charging time.

5. The charging device (1) according to claim 1 or 2. Its features are, The regulating unit (9) is configured to regulate the third charging current (I3) in such a way that the second secondary reaction current (J2) of the energy storage (2) is minimized.

6. The charging device (1) according to claim 5. Its features are, The charging device (1) has a summing device (8) arranged between the control unit (12) and the adjustment unit (9) on one side and the output connector (13) of the charging device (1) on the other side. The summing device (8) is configured to add the first charging current (I1) or the second charging current (I2) from the control unit (12) together with the third charging current (I3) from the adjustment unit (9) to generate a fourth charging current (I4).

7. The charging device (1) according to claim 6. Its features are, The charging device (1) has a low-pass filter (4) arranged between the control unit (12) and the summing device (8), wherein the low-pass filter (4) is configured to smooth the first charging current (I1) into a second charging current (I2).

8. The charging device (1) according to any one of claims 6 or 7. Its features are, The charging device (1) has a comparison device (10) arranged between the control unit (12) and the aging analysis device (7) on one side and the summing device (8) on the other side, wherein the comparison device (10) is configured to compare the first sub-reaction current (J1) with the second sub-reaction current (J2).

9. A method for charging an energy storage device (2) using a charging device (1) according to any one of claims 1 to 8, in, The method includes control method steps and adjustment method steps, which operate simultaneously. The energy storage device (2) is charged to a predetermined state of charge within a pre-given charging time, and the charging current and side reaction current of the energy storage device (2) are set for this purpose.

10. The method (100) according to claim 9. Its features are, The current state of charge and current aging state and / or the second secondary reaction current (J2) are obtained from the sensor data of the energy storage (2). In this process, the first charging current (I1) and the first secondary reaction current (J1) are generated by means of the model of the energy storage (2) using the current state of charge, the specified state of charge and the available charging time.

11. The method (100) according to claim 10. Its features are, The first secondary reaction current (J1) is compared with the second secondary reaction current (J2) to generate a third charging current (I3), wherein the third charging current (I3) is equal to zero when the first secondary reaction current (J1) has the same value as the second secondary reaction current (J2), and / or the third charging current (I3) is determined such that the aging of the energy storage device (2) is minimized. The third charging current (I3) is added together with the second charging current (I2) from the control unit (12) to generate a fourth charging current (I4), wherein when the third charging current (I3) is equal to zero, the fourth charging current (I4) has the same value as the second charging current (I2). The energy storage device (2) is charged with the fourth charging current (I4).

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