Method for charging an electrochemical energy storage device

Description

[0001] The invention is based on a method for charging an electrochemical energy storage device, a device for operating an electrochemical energy storage unit and a use according to the preamble of the independent claims. State of the art

[0002] If an electric truck (e-truck) is parked at a charging station for longer than a rapid charge, the charging station shuts down and no further charge flows into the battery. At the same time, the driver should vacate the charging bay and make it available for other e-trucks, which would mean interrupting their mandatory driving break, which is recorded on the tachograph. After the charging process is complete, the battery will not be charged again until the driver resumes driving.

[0003] According to the current state of the art, fast charging processes for batteries are carried out between 20% state of charge (SOC) and a maximum of 80-85% SOC. The remaining 15-20% SOC cannot be charged during the short break time of 45 minutes, for example, resulting in a significant loss of range.

[0004] When approximately 80% SOC is reached, the fast charging process is usually terminated by the battery management system (BMS). However, the vehicle, such as an electric truck, may still be at the charging station, perhaps due to an extended break from driving, and the vehicle battery could still be charged.

[0005] The document US 2013 / 221918 discloses a method for charging a vehicle.

[0006] The object of the present invention is to further improve the state of the art. This object is achieved by the features of the independent claims. Disclosure of the inventionAdvantages of the invention

[0007] The procedure according to the invention with the characterizing features of the independent claims has the advantage that the method for charging an electrochemical energy storage device comprises the following steps: a) detecting a target charging mode value which represents a target charging mode of the electrochemical energy storage device; b) comparing the detected target charging mode value with a predetermined fast charging mode value, which represents a fast charging mode of the electrochemical energy storage device; c) rapid charging of the electrochemical energy storage device in a first charging phase with a direct current of a predetermined constant current (CC) depending on the comparison; d) Continuously detecting a first state of charge variable of the electrochemical energy storage device, which represents a state of charge (SOC) of the electrochemical energy storage device; e) comparing the detected first state of charge variable with a predetermined first target state of charge variable; g) charging the electrochemical energy storage device in a second charging phase with an alternating current with a predetermined constant current intensity (CC) depending on the comparison, wherein the predetermined current intensity of the alternating current in the second charging phase is substantially lower than the predetermined current intensity of the direct current in the first charging phase.

[0008] Advantageously, after a first charging phase in a fast charging mode, the vehicle immediately switches to a second charging phase, thus enabling a further charging process which not only increases the current charge level of the electrochemical energy storage device, but also counteracts the relaxation which is most pronounced after a fast charge and thus increases the charge level of the electrochemical energy storage device after the relaxation and thus reflects the actual charge level and the available amount of energy or capacity, which is ultimately decisive for the range.

[0009] Further advantageous embodiments are the subject of the subclaims.

[0010] The method according to the invention for charging an electrochemical energy storage device further comprises the following step: f) waiting a predetermined period of time for a cooling phase of the electrochemical energy storage device;

[0011] This reduces the temperature of the electrochemical energy storage device, which advantageously results in a lower aging behavior.

[0012] The method according to the invention for charging an electrochemical energy storage device further comprises the following steps: h) Continuously detecting a second state of charge variable of the electrochemical energy storage device, which represents a second state of charge (SOC) of the electrochemical energy storage device; i) comparing the detected second state of charge variable with a predetermined second target state of charge variable; j) Charging the electrochemical energy storage device in a further charging phase with an alternating voltage with a predetermined constant electrical voltage (constant voltage, CV).

[0013] Advantageously, the relaxation, which is most pronounced after a fast charge, is counteracted and thus the charge state of the electrochemical energy storage device after the relaxation and its available energy quantity or capacity is increased.

[0014] During the first charging phase, charging occurs at a power between 150 kW and 12 MW. Advantageously, today's CCS connectors for direct and alternating current allow high charging powers of up to approximately 375 kW.

[0015] In the second charging phase, charging takes place with a power between 22kW and 160kW.

[0016] The specified first target state of charge corresponds to a state of charge between 75% and 85% and the specified second target state of charge corresponds to a state of charge between 85% and 95% of a maximum state of charge of the electrochemical energy storage device.

[0017] A device according to the invention for operating an electrochemical energy storage unit comprises an electrochemical energy storage device, a current sensor for detecting an electrical current of the electrochemical energy storage device, a voltage sensor for detecting an electrical voltage of the electrochemical energy storage device, and at least one means, in particular an electronic battery management control device, which are configured to carry out the steps of the method according to the invention for charging an electrochemical energy storage device.

[0018] According to an advantageous embodiment of the invention, a computer program is provided, comprising instructions which cause the device for operating a battery to carry out the method steps according to the invention.

[0019] Furthermore, a machine-readable storage medium is provided on which the computer program is stored.

[0020] A method according to the invention for charging an electrochemical energy storage device and / or a device according to the invention are advantageously used in electrochemical energy storage devices for electric vehicles, fuel cell vehicles, hybrid vehicles, plug-in hybrid vehicles, aircraft, pedelecs or e-bikes. Short description of the characters

[0021] Embodiments of the invention are illustrated in the drawing and explained in more detail in the following description.

[0022] Further advantages and advantageous embodiments of the inventive objects are illustrated by the drawings and explained in the following description. It should be noted that the drawings are for descriptive purposes only and are not intended to limit the invention in any way. Furthermore, the features described below may constitute an object of the invention, individually or in any combination, unless the context explicitly indicates otherwise.

[0023] They show: Fig. 1 a schematic representation of a loading profile according to an embodiment of a method according to the invention; and Fig. 2 a flowchart of an embodiment of a method according to the invention for charging an electrochemical energy storage device. Detailed description of the implementation examples

[0024] The same reference numerals denote the same device components in all figures.

[0025] Fig. Figure 1 shows a schematic representation of a charging profile 100 according to an embodiment of a method according to the invention. Time is plotted on the x-axis, and a current strength or a state of charge of an electrochemical energy storage device is plotted on the y-axis.

[0026] In a first charging phase 101, an electrochemical energy storage device is charged with a direct current with a predetermined constant current intensity 104 and power levels between 150 kW and 12 MW, whereby a state of charge (SOC) 107 of the electrochemical energy storage device increases.

[0027] In a second charging phase 102, the electrochemical energy storage device is charged with an alternating current with a predetermined constant current 105, and power levels between 22 kW and 160 kW are charged. Due to relaxation, the state of charge 108 of the electrochemical energy storage device would decrease. The pure charging process in the second charging phase 102 would increase the state of charge 109 of the electrochemical energy storage device. Due to both effects, the state of charge 110 initially decreases slightly, but then increases due to a superposition of the relaxation and the charging process.

[0028] This creates a significant state of charge delta 111 between the state of charge after the first charging phase 101 and the second charging phase 102 or a further charging phase 103, during which charging takes place with a predetermined constant electrical voltage, i.e. a decreasing current 106.

[0029] Fig.2 shows a flowchart of an embodiment of a method according to the invention for charging an electrochemical energy storage device.

[0030] In step 200, a target charging mode variable is detected, which represents a target charging mode of the electrochemical energy storage device.

[0031] In one embodiment, a selector switch can advantageously be attached to a charging socket, which can be used to select a charging strategy, for example between a fast-charging mode and a regular charging mode. In the regular charging mode, the electrochemical energy storage device can be charged more stress-free, which is reflected in lower aging behavior and a corresponding remaining useful life (RUL). This regular charging mode can be selected, for example, if the e-truck is being charged overnight or on the weekend and sufficient time is available for charging. The fast-charging mode is used to charge the electrochemical energy storage device during short break periods.

[0032] In step 201, the detected target charging mode value is compared with a predetermined fast charging mode value, which represents a fast charging mode of the electrochemical energy storage device.

[0033] If a fast-charging mode is selected, the electrochemical energy storage device is quickly charged in a first charging phase 101 with a direct current at a predetermined constant current (CC) in step 202. Otherwise, the method continues in step 205.

[0034] In step 203, a first state of charge variable of the electrochemical energy storage device, which represents a state of charge (SOC) of the electrochemical energy storage device, is detected.

[0035] In step 204, the detected first state of charge variable is compared with a predetermined first target state of charge variable. If the target state of charge is reached, the method continues in step 205. Otherwise, the method continues in step 202, and the electrochemical energy storage device continues to be rapidly charged.

[0036] In step 205, the electrochemical energy storage device is charged in a second charging phase 102 with an alternating current having a predetermined constant current intensity (CC), wherein the predetermined current intensity of the alternating current in the second charging phase 102 is substantially lower than the predetermined current intensity of the direct current in the first charging phase 101.

[0037] In step 206, a second state of charge variable of the electrochemical energy storage device is detected, which represents a second state of charge (SOC) of the electrochemical energy storage device.

[0038] In step 207, the detected second state of charge variable is compared with a predefined second target state of charge variable. If the target state of charge is reached, the method is terminated in step 209. Otherwise, the method continues in step 208.

[0039] In step 208, the electrochemical energy storage device is charged in a further charging phase 103 with an alternating voltage with a predetermined constant electrical voltage (constant voltage, CV).

[0040] In step 209, the method is terminated if, for example, the target charge level has been reached or the charging process is terminated manually. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 2013 / 221918

[0005]

Claims

[1] Method for charging an electrochemical energy storage device, comprising the following steps: a) (200) detecting a target charging mode variable which represents a target charging mode of the electrochemical energy storage device; b) (201) comparing the detected target charging mode value with a predetermined fast charging mode value representing a fast charging mode of the electrochemical energy storage device; c) (202) rapid charging of the electrochemical energy storage device in a first charging phase (101) with a direct current with a predetermined constant current (CC) (104) depending on the comparison; d) (203) Continuously detecting a first state of charge variable of the electrochemical energy storage device, which represents a state of charge (SOC) of the electrochemical energy storage device; e) (204) comparing the detected first state of charge variable with a predetermined first target state of charge variable; g) (205) charging the electrochemical energy store in a second charging phase (102) with an alternating current with a predetermined constant current intensity (CC) (105) depending on the comparison, wherein the predetermined current intensity (105) of the alternating current in the second charging phase (102) is substantially lower than the predetermined current intensity (104) of the direct current in the first charging phase (101). [2] Method for charging an electrochemical energy storage device according to claim 1, further comprising the following step: f) waiting a predetermined period of time for a cooling phase of the electrochemical energy storage device; [3] Method for charging an electrochemical energy storage device according to one of the preceding claims, further comprising the following steps: h) (206) Continuously detecting a second state of charge variable of the electrochemical energy storage device, which represents a second state of charge (SOC) of the electrochemical energy storage device; i) (207) comparing the detected second state of charge variable with a predetermined second target state of charge variable; j) (208) Charging the electrochemical energy storage device in a further charging phase (103) with an alternating voltage with a predetermined constant electrical voltage (constant voltage, CV). [4] Method for charging an electrochemical energy storage device according to one of the preceding claims, characterized by that in the first charging phase (101) charging takes place with a power between 150kW and 12MW. [5] Method for charging an electrochemical energy storage device according to one of the preceding claims, characterized by that in the second charging phase (102) charging takes place with a power between 22kW and 160kW. [6] Method for charging an electrochemical energy storage device according to one of the preceding claims, characterized by that the predetermined first target state of charge value corresponds to a state of charge between 75% and 85% and the predetermined second target state of charge value corresponds to a state of charge between 85% and 95% of a maximum state of charge of the electrochemical energy storage device. [7] Device for operating an electrochemical energy storage unit, comprising an electrochemical energy store, a current sensor for detecting an electrical current of the electrochemical energy store, a voltage sensor for detecting an electrical voltage of the electrochemical energy store, and at least one means, in particular an electronic battery management control unit, which are configured to carry out the steps of the method for charging an electrochemical energy store according to one of claims 1 to 6. [8] A computer program comprising instructions causing the apparatus of claim 7 to perform the method steps of any one of claims 1 to 6. [9] A machine-readable storage medium on which the computer program according to claim 8 is stored. [10] Use of a method for charging an electrochemical energy storage device according to one of claims 1 to 6 and / or a device according to claim 7 in electrochemical energy storage devices for electric vehicles, fuel cell vehicles, hybrid vehicles, plug-in hybrid vehicles, aircraft, pedelecs or e-bikes.

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