Control Unit and Method for Conditioning an Energy Store of a Vehicle

Abstract

A control unit for a vehicle includes an electric energy store for storing electric energy for an electric drive machine. The control unit is designed to determine that the vehicle is driving to a charging station in order to charge the energy store. In response to the determination, the control unit is additionally designed to initiate one or more usage-neutral or usage-reducing measures while the vehicle is traveling in order to reduce the temperature of the energy store in preparation for the charging process of the energy store.

Claims

1.-11. (canceled)

12. A control unit for a vehicle comprising: an electrical energy store for storing electrical energy for an electric drive machine, wherein the control unit is designed to: determine that the vehicle is driving to a charging station for charging the energy store; and respond to the determination by initiating one or more consumption-neutral or consumption-reducing measures during the journey of the vehicle in order to reduce the temperature of the energy store in preparation for the charging of the energy store.

13. The control unit according to claim 12, wherein the one or more measures comprise: activating an energy-saving mode of an electrical consumer of the vehicle; and deactivating the electrical consumer.

14. The control unit according to claim 12, wherein the one or more measures comprise reducing a vehicle speed of the vehicle via the electric drive machine.

15. The control unit according to claim 14, wherein the control unit is further designed to: ascertain time information with respect to a reduction of a required charging time for charging the energy store on account of reducing the vehicle speed; and ascertain the vehicle speed in dependence on the time information so that an overall expenditure of time for the journey to the charging station and for the charging of the energy store is reduced.

16. The control unit according to claim 12, wherein the control unit is further designed to: determine the charging power with which the energy store is to be charged; and only initiate the one or more measures when the charging power is equal to or greater than a power threshold value.

17. The control unit according to claim 12, wherein the one or more measures are aimed to reduce the temperature of the energy store at the beginning of charging in comparison with a temperature that would occur if the one or more measures were not carried out.

18. The control unit according to claim 12, wherein the control unit is further designed to: ascertain navigation data with respect to a planned travel route of the vehicle; or ascertain input data with respect to an input by a user via a user interface of the vehicle; and determine, on the basis of the navigation data or the input data, that the vehicle is driving to a charging station for charging the energy store.

19. The control unit according to claim 12, wherein the control unit is further designed to: produce an optical or acoustic or haptic output to a user of the vehicle in order to indicate that the one or more measures for reducing the temperature of the energy store should be carried out; and initiate the one or more measures in dependence on an input by the user.

20. The control unit according to claim 12, wherein the one or more measures comprise increasing an air stream for cooling the electrical energy store.

21. The control unit according to claim 12, wherein the control unit is further designed to: inform the charging station in advance via a wireless communication link that the vehicle is driving to the charging station to charge the energy store; or reserve the charging station for charging the energy store.

22. A method for operating a vehicle comprising an electrical energy store for storing electrical energy for an electric drive machine, the method comprising: determining that the vehicle is driving to a charging station for charging the energy store; and responding to the determination by carrying out one or more consumption-neutral or consumption-reducing measures during the journey of the vehicle in order to reduce the temperature of the energy store in preparation for the charging of the energy store.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 shows components that may be given by way of example of a vehicle.

[0028] FIG. 2 shows a flow diagram of a method that may be given by way of example for preparing a vehicle for a charging process.

DETAILED DESCRIPTION OF THE DRAWINGS

[0029] As explained at the beginning, the present document is concerned with increasing the energy efficiency of an at least partially electrically driven vehicle and in particular with increasing the energy efficiency of a (rapid) charging process for charging the energy store of a vehicle.

[0030] The electrical energy store of a vehicle should typically not exceed a certain maximum temperature, in particular during a charging process. However, in the course of a charging process, thermal power is produced as a result of the flowing charging current in the energy store of the vehicle and causes the temperature of the energy store to increase. The thermal power depends in this case on the charging power, and typically increases with increasing charging power. During a charging process, the energy store may be cooled actively (by operation of a cooling system of the vehicle) and/or passively (by convection with the ambient air), in order to dissipate at least part of the thermal power.

[0031] The cooling power required for cooling the energy store may be reduced by reducing the temperature of the energy store at the beginning of a charging process. In particular, reducing the initial temperature of the energy store at the beginning of a charging process allows the amount of thermal energy that can be taken up by the energy store until the maximum temperature is reached, and consequently does not have to be used up in the form of cooling power to be increased.

[0032] FIG. 1 shows a block diagram with components that may be given by way of example of a vehicle 100. The vehicle 100 comprises a control unit 101, which is designed to determine that the vehicle 100 is being driven to a charging station for charging the electrical energy store 103. This may be ascertained for example on the basis of input data from a user interface 102 of the vehicle 100. Alternatively or in addition, this may be ascertained on the basis of the navigation data of a navigation system (for example on the basis of route planning of the navigation system).

[0033] The control unit 101 may also be designed to respond to the determination that the vehicle 100 is on its way to a charging station by initiating one or more measures to lower the temperature of the energy store 103. In particular, one or more measures by which the temperature of the energy store 103 when reaching the charging station is lowered (in comparison with the temperature that the energy store 103 would have when reaching the charging station without carrying out the one or more measures) may be initiated.

[0034] One possible measure would in this case be the activation of a cooling system 104 of the energy store 103. However, the operation of a cooling system 104 typically leads to an increased (electrical) energy consumption of the vehicle 100, and consequently to an additional lowering of the state of charge of the energy store 103. As a consequence of this, the amount of electrical energy that can be taken up by the energy store 103 during the charging process is increased, whereby in turn the amount of thermal energy produced is increased. With the preparation operation of a cooling system 104, it is consequently indeed possible for the temperature of an energy store 103 when reaching a charging station to be reduced (in order to provide a greater temperature buffer for the charging process). On the other hand, the reduced state of charge of the energy store 103 when reaching the charging station would have the effect that the amount of electrical energy to be charged is increased, so that the temperature buffer is at least partially diminished again.

[0035] The one or more measures therefore preferably comprise one or more measures that are at least neutral, and preferably reducing, with respect to the electrical consumption of the vehicle 100. In particular, in preparation for the charging process during the journey of the vehicle 100, one or more electrical consumers 105 of the vehicle 100 may be deactivated or set to an energy-saving mode, in order to lower the electrical consumption of the vehicle 100 and consequently the loading of the energy store 103 and thus the temperature of the energy store 103 (or to reduce the increase in the temperature of the energy store 103). Alternatively or in addition, one or more (consumption-neutral) measures may be initiated, in order to increase the cooling power for cooling the energy store 103 during the journey of the vehicle 100.

[0036] Measures that may be given by way of example are: [0037] Reducing the vehicle speed, whereby the required drive power and the electrical power consumption of the vehicle 100 are reduced. This results in a reduction of the heating up or a cooling down of the energy store 103. [0038] An increased flow can be directed onto the energy store 103 during the journey of the vehicle 100 by fins at the front of the vehicle or by one or more corresponding devices, which improves the cooling of the energy store 103. In this case, the energy store 103 may possibly have cooling ribs, in order to make improved heat exchange possible. Alternatively or in addition, the vehicle speed of the vehicle 100 may be adapted in order to improve the conditions for the flow directed onto the energy store 103 in relation to the heat dissipated. [0039] Switching off or reducing one or more electrical consumers for comfort functions, such as seat heating or an air-conditioning system.

[0040] The lowering of the vehicle speed may be performed in such a way that the sum of the travel time to the charging station and the charging time for charging the energy store 103 is improved, in particular minimized. The reduction of the initial temperature of the energy store 103 at the beginning of a charging process typically makes it possible to increase the charging power of the charging process, and consequently to speed up the charging process. Furthermore, lowering the vehicle speed typically leads to reduced energy consumption, and consequently to a higher state of charge of the energy store 103 when reaching the charging station, which likewise has positive effects on the required charging time. Consequently, even with a reduced vehicle speed (and the associated prolongment of the travel time to the charging station), the sum of the travel time and the charging time can be reduced.

[0041] The one or more measures for reducing the temperature of the energy store 103 in preparation for a charging process may be combined in a driving mode of the vehicle 100 (for example a charging-preparation driving mode). The control unit 101 may be designed to issue via the user interface 102 of the vehicle 100 an output to a user, in particular a driver, of the vehicle 100 that indicates that the charging-preparation driving mode should be activated in preparation for the charging process. The charging-preparation driving mode may then be activated or not, in dependence on a detected user input.

[0042] FIG. 2 shows a flow diagram of a method 200 that may be given by way of example for operating a vehicle 100. The vehicle 100 comprises an electrical energy store 103 for storing electrical energy for an electric drive machine. The method 200 may be performed by a control unit 101 of the vehicle 100. The method 200 comprises the determination 201 that the vehicle 100 is driving to a charging station for charging the energy store 103. This may be ascertained or determined for example on the basis of a planned travel route of the vehicle 100 and/or on the basis of an input by a user of the vehicle 100.

[0043] The method 200 also comprises responding to the determination that the vehicle 100 is on its way to a charging station for charging the vehicle 100 by carrying out 202 one or more consumption-neutral or consumption-reducing measures during the journey of the vehicle 100 in order to reduce the temperature of the energy store 103 in preparation for the charging of the energy store 103. In particular, the one or more measures can bring about the effect that the energy store 103 has a reduced initial temperature at the beginning of the charging process at the charging station. Thus, the charging power of the charging process can be increased, and consequently the charging time can be shortened. Furthermore, the restriction to carrying out consumption-neutral or consumption-reducing measures has the effect that the energy store 103 has a relatively increased state of charge at the beginning of the charging process, so that the required charging time for reaching a certain target state of charge (for example of almost 100%) can be shortened further.

[0044] The measures described in this document make it possible to prepare the energy store 103 of a vehicle 100 for a (rapid) charging process in an energy-efficient way. Thus, the energy efficiency of a vehicle 100 can be increased. Furthermore, the charging time for a charging operation can thus be reduced.

[0045] The present subject matter is not restricted to the exemplary embodiments shown. In particular, it should be noted that the description and the figures are only intended to illustrate the principle of the proposed methods, devices and systems.