METHOD AND TESTING SYSTEM FOR TESTING THE CONDITION OF A BATTERY IN A VEHICLE

Description

[0001] The presented invention relates to a method and testing system for testing the condition of a battery in a vehicle.

[0002] Batteries, especially traction batteries for powering a vehicle's drive system, are of considerable monetary value. Since batteries are subject to varying degrees of wear depending on their usage and application, the condition of different used batteries can differ significantly, even with the same vehicle mileage.

[0003] A user of a vehicle can only gain limited insights into the condition of a vehicle's battery based on the vehicle's operating parameters, such as its mileage.

[0004] Since a battery's condition is not directly perceptible or verifiable by a user, information about its state can easily be falsified. In particular, values ​​stored in memory from a test procedure can easily be overwritten or manipulated.

[0005] To assess the condition of a battery, DE 101 2018 206 414 A1 describes a method for determining a count value to count the battery's effective lifetime to date.

[0006] US 2012 / 0316813 A1 describes a method for assessing the condition of a battery, in which an amount of energy already provided by the battery and / or an estimate of the remaining battery life is determined based on the battery's properties.

[0007] DE 10 2018 201 138 A1 describes a method for determining wear values ​​for electric vehicles, in which a distance traveled since initial commissioning and a number of charging processes are combined to form a wear indicator.

[0008] Furthermore, the following website deals with a similar topic: https: / / www.facebook.com / Aviloobatterydiagnostic / , see e.g. XP093018102, XP055832665.

[0009] Against this background, one of the objectives of the presented invention is to provide a user of a vehicle with a means of reliably and securely checking the condition of a battery in a vehicle.

[0010] The aforementioned problem is solved by a method and a testing system according to the respective independent claims. Preferred embodiments of the invention are described in the description, drawings, and dependent claims. Features disclosed with respect to the individual aspects of the invention can be combined in such a way that the disclosures relating to the aspects of the invention always refer to each other.

[0011] According to a first aspect of the presented invention, a method for testing the condition of a battery in a vehicle is presented to solve the aforementioned problem. The method comprises a discharge step for discharging the battery to a predetermined state of charge, a charging step for charging the battery with a predetermined charging current until the battery is fully charged, a determination step for determining the total capacity of the battery based on a charging time and the charging current, a certification step for creating a signed certificate describing the total capacity, a backup step for saving the certificate in a memory, and an output step for printing the certificate on an output unit.

[0012] In the context of the presented invention, a battery's state is understood to mean its suitability for performing a function of the battery, i.e., for storing and releasing electricity.

[0013] In the context of the presented invention, a certificate is understood to be a digital data set that confirms certain properties of a digital object and whose authenticity and integrity can be verified by cryptographic methods.

[0014] The presented invention is based on a standardized charging process for determining the total capacity of a battery. The standardized charging process comprises a complete discharge, i.e., a discharge to a predetermined state of charge, and a subsequent recharge, so that the total capacity and, consequently, the current state of the battery can be determined based on the duration of the corresponding charging process and the charging current used.

[0015] In order to provide trustworthy and, if possible, falsification-proof information about the determined state of a respective battery, the invention provides that information determined by the presented method about the total capacity or the current state of the battery is incorporated into a digital certificate and stored on a storage device, in particular a centrally managed cloud storage device.

[0016] Accordingly, a user can verify the respective information about the battery's condition based on the certificate itself and, if applicable, on a history of previously stored certificates or determined battery states.

[0017] To increase the accuracy of a given determined characteristic value of a battery's condition, the presented procedure or a discharge and recharge of the battery can be repeated in several cycles.

[0018] It may be provided that the battery is discharged by activating a consumer of the vehicle and / or by bidirectional charging.

[0019] In order to achieve the predetermined state of charge provided for according to the invention or to completely discharge the battery, a corresponding vehicle can be driven as far as possible.

[0020] To reduce the risk of being stranded on the road due to a depleted battery, a non-powered electrical consumer can be used to recharge the battery to the required charge level while the vehicle is stationary. This could include, for example, an air conditioner, an electric heating system, a circulation pump, or any other electrical consumer in the vehicle.

[0021] Alternatively or additionally to activating a vehicle's energy consumer, the vehicle can be configured to feed electrical energy into a power grid or energy storage system via a bidirectional charging system, thereby discharging the battery to the specified state of charge.

[0022] It may also be provided that the procedure is started by a start signal transmitted wirelessly to the vehicle from a computing unit.

[0023] To avoid requiring a user to directly operate a vehicle to determine its battery status, the process can be initiated remotely by a computing unit located away from the vehicle, such as a smartphone or computer. This could involve, for example, a program on a workshop computer, an application running on a smartphone, or an internet portal where the generation of a corresponding start signal can be purchased. A start signal to initiate the described process can be transmitted directly from the computing unit to the vehicle or, in response to user input on the computing unit, from a central management server to the vehicle.

[0024] In response to receiving a start signal, each vehicle begins to discharge its battery.

[0025] It may also be stipulated that the battery be left in a resting state for at least a specified period of time before charging the battery.

[0026] In order to achieve a defined and correspondingly comparable starting point for charging a respective battery, a rest period can be provided in which the battery returns to a predetermined starting state and relaxes after being discharged.

[0027] It may also be provided that the current state of the battery is determined immediately before charging.

[0028] To accurately determine a battery's initial state and thus infer its total capacity, the initial state can be determined immediately before charging, for example, by measuring the cell voltage. The resulting initial state can then be compared with the final state after charging, and the difference can be used to determine the battery's condition.

[0029] It may also be provided that the certificate is created by a computer connected to the vehicle via a communication interface or by a computing unit of the vehicle.

[0030] To create a certificate that is as forgery-proof as possible, a central and appropriately well-monitored server can be used. Alternatively, a certificate can be generated directly for each vehicle and later validated by a security authority, such as a workshop or a central server, using a cryptographic key.

[0031] It may also be provided that the certificate is issued on an output unit of the vehicle and / or a mobile computing unit.

[0032] To display information about the battery status of a given vehicle to a user, a certificate created according to the invention can be transferred to a mobile computing unit, such as a smartphone, and / or displayed on an output unit of the vehicle, such as an HMI display. The certificate can be loaded from the vehicle's memory or from a central server.

[0033] The following is an exemplary overall sequence of a possible implementation of the presented procedure; 1. A customer activates a "Health Certificate" service, for example, in a workshop, an online store, or an in-car app store. 2. The service is activated on an administration server, and a corresponding vehicle is provided with a start command to perform the described procedure. 3. The vehicle informs the customer about the progress of the procedure, for example, via email or a smartphone app. 4. The customer initiates a test cycle in the vehicle or by sending a control command to the vehicle. 5. The customer receives a notification to discharge the vehicle's battery or to discharge it via bidirectional charging. 6. The vehicle automatically discharges the battery to a predetermined level using non-propulsion-related consumers if the customer has not discharged the battery to the predetermined level. 7.The vehicle enters a defined waiting period to allow the battery to relax and reach a defined state. 8. After the waiting period, the battery is calibrated to its current state of charge by measuring cell voltage or by measuring other physical properties of the battery. 9. The vehicle begins a charging cycle with a predefined charging current, which can be selected based on cell type and / or the battery's chemical structure. 10. The battery is fully charged, ignoring any customer settings. 11. Finally, the battery's total capacity is determined. 12. The determined total capacity is saved and signed on the management server and / or stored in the vehicle's memory. 13. A certificate is issued and displayed to the customer on a display unit. 14. To increase accuracy, the charging cycles can optionally be repeated multiple times.

[0034] In a second aspect, the presented invention relates to a test system for checking the condition of a battery in a vehicle. The test system comprises a processing unit. The processing unit is configured to transmit a discharge command to a vehicle control unit to discharge the battery to a predetermined state of charge, to transmit a charge command to the vehicle control unit to charge the battery with a predetermined charging current until the battery is fully charged, to determine the total capacity of the battery based on a charging time and charging current, to generate a signed certificate describing the total capacity, to store the certificate in a memory, and to output the certificate on an output unit.

[0035] The presented testing system is used in particular for carrying out the presented procedure.

[0036] The computing unit may be a computer connected to the vehicle via a communication interface or a processor located in the vehicle.

[0037] A computing unit connected to each vehicle via a communication interface allows a large number of vehicles to be configured to carry out the presented procedure, requiring only a suitable communication interface, such as a wireless interface, in particular a mobile communication interface, on each vehicle.

[0038] It may also be provided that the computing unit includes a communication interface for communication with a user interface of a user, through which the computing unit can be activated in order to execute a possible embodiment of the presented procedure.

[0039] It may also be provided that the verification system includes a security server configured to verify respective certificates using a cryptographic key.

[0040] A security server allows a user, such as a vehicle buyer, to verify the authenticity of a certificate sent by a seller. The buyer sends the certificate to the security server. The security server compares a cryptographic key contained in the certificate with a local cryptographic key on the security server and generates a validation message. If the cryptographic keys match, the validation message contains an authentication confirmation; if they do not match, the validation message denies the authenticity.

[0041] Further advantages, features and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings.

[0042] The features mentioned in the claims and the description can each be essential to the invention individually or in any combination. This shows: Fig. 1 shows a possible embodiment of the presented method, Fig. 2 shows a possible embodiment of the presented testing system.

[0043] In Fig. 1 A procedure 100 is shown.

[0044] The procedure 100 comprises a discharge step 101 to discharge the battery to a predetermined state of charge, a charging step 103 to charge the battery with a predetermined charging current until the battery is fully charged, a determination step 105 to determine a total capacity of the battery based on a charging time and the charging current, a certification step 107 to create a signed certificate describing the total capacity, a backup step 109 to save the certificate in a memory and an output step 111 to output the certificate on an output unit.

[0045] In Fig. 2 A test system 200 is shown.

[0046] The test system 200 comprises a computing unit 201 and an optional communication interface 203.

[0047] The communication interface 203 can be used to send start signals for initiating a procedure, such as procedure 100 according to Fig. 1can be received. Alternatively or additionally, an output signal, which may include a generated certificate, can be transmitted via the communication interface 203 to an output unit 205, such as a smartphone.

[0048] Accordingly, a seller of a vehicle 207 can access an internet portal via his smartphone 209, purchase an operation there to generate a start command that configures the testing system 200 to carry out the procedure 100 according to Fig. 1 to carry out and to create a certificate 213 about the condition of a battery 211 of the vehicle 207.

[0049] Certificate 213 is issued to a buyer on the output unit 205, in this case the buyer's smartphone.

[0050] Certificate 213 may include a digital signature, which allows the buyer to identify a trusted source for generating the certificate.

[0051] Additionally or alternatively, the buyer can transfer certificate 213 to a security server 215 for verification. The security server can verify or authenticate certificate 213, for example, using a cryptographic key included in certificate 213. Reference symbol list

[0052] 100 Procedure 101 Discharge step 103 Charging step 105 Detection step 107 Certification step 109 Backup step 111 Output step 200 Test system 201 Computing unit 203 Communication interface 205 Output unit 207 Vehicle 209 Smartphone 211 Battery 213 Certificate 215 Security server

Claims

1. Method (100) for testing a state of a battery (211) in a vehicle (207), wherein the method (100) comprises: - discharging (101) the battery (211) up to a predetermined state of charge, - charging (103) the battery (211) using a predetermined charging current until the battery (211) is fully charged, - determining (105) a total capacity of the battery (211) on the basis of a charging time and the charging current, - generating (107) a signed certificate (213) which describes the total capacity, - saving (109) the certificate (213) in a memory, - outputting (111) the certificate (213) on an output unit (205).

2. Method (100) according to claim 1, characterized in that the battery (211) is discharged by activating an energy consumer of the vehicle (207) and / or by bidirectional charging.

3. Method (100) according to claim 1 or claim 2, characterized in that the method (100) is started by a start signal transmitted wirelessly from a computing unit (201) to the vehicle (207).

4. Method (100) according to any of the preceding claims, characterized in that, before charging the battery (211), the battery (211) is left in an idle state for at least a predetermined period of time.

5. Method (100) according to any of the preceding claims, characterized in that a present state of the battery (211) is determined immediately before charging the battery (211).

6. Method (100) according to any of the preceding claims, characterized in that the certificate (213) is created by a computer or a computing unit (201) of the vehicle connected to the vehicle (207) via a communication interface (203).

7. Method (100) according to any of the preceding claims, characterized in that the certificate (213) is output on an output unit of the vehicle (207) and / or a mobile computing unit (205).

8. Test system (200) for testing a state of a battery (211) in a vehicle (207), wherein the testing system (200) comprises a computing unit (201), and wherein the computing unit (201) is configured to transmit a discharge command to a control device of the vehicle (207) in order to discharge the battery (211) up to a predetermined state of charge, transmit a charging command to the control unit of the vehicle (207) in order to charge the battery (211) using a predetermined charging current until the battery (211) is fully charged, determine a total capacity of the battery (211) on the basis of a charging time and the charging current, create a signed certificate (213) which describes the total capacity, save the certificate (213) in a memory, and output the certificate (213) on an output unit (205).

9. Test system (200) according to claim 8, characterized in that the computing unit (201) is a computer connected to the vehicle (207) via a communication interface (203) or is a processor located in the vehicle (207).

10. Test system (200) according to claim 8 or claim 9, characterized in that the computing unit (201) comprises a communication interface (203) for communicating with a user interface of a user, by means of which the computing unit (201) can be activated in order to carry out a method according to any of claims 1 to 7.

11. Test system (200) according to any of claims 8 to 10, characterized in that the test system (200) comprises a security server (215) which is configured to verify the relevant certificates (213) using a cryptographic key.