INTERMEDIATE STORAGE FACILITY FOR BATTERY UNITS

Abstract

The invention relates to an intermediate storage facility for battery units, having a multiplicity of battery units, having an inverter and/or rectifier, a power supply system and a controller, wherein each battery unit has at least one chargeable battery cell and a battery management system for monitoring and regulating the battery cell, at least two battery units are connected electrically in series to form a battery chain, the battery chain is electrically connected to the power supply system via the inverter and/or rectifier, and the controller has a communication connection to all the battery management systems and is configured to bring about charging of the battery cell with electrical energy from the power supply system, to feed electrical energy in to the power supply system by discharging the battery cell and/or to bring about connection and/or disconnection of the battery unit to or from the inverter and/or rectifier.

Claims

1. Method for storing a battery unit in an intermediate storage facility, having a multiplicity of battery units, having an inverter and/or rectifier, a power supply system and a controller, wherein each battery unit has at least one chargeable battery cell and a battery management system for monitoring and regulating the battery cell, at least two battery units are connected electrically in series to form a battery chain, the battery chain is electrically connected to the power supply system via the inverter and/or rectifier, and the controller has a communication connection to all the battery management systems and is configured to bring about charging of the battery cell and/or of the battery unit with electrical energy from the power supply system, to feed electrical energy in to the power supply system by discharging the battery cell and/or the battery unit and/or to bring about connection and/or disconnection of the battery unit to or from the inverter and/or rectifier, and comprising the step: exchanging all the battery units of each battery chain at the latest after 14 days and at the latest after an energy throughput of the battery chain of ≦3000 kWh.

2. Method according to claim 1, having a multiplicity of battery chains which are respectively connected to the inverter and/or rectifier and connected electrically in parallel with one another.

3. Method according to claim 1, having a multiplicity of inverters and/or rectifiers and each having one battery chain which is electrically connected to the power supply system via the respective inverter and rectifier.

4. Method according to claim 1, wherein the controller is designed to select a battery chain so that the selected battery chain is charged with electrical energy from the power supply system within a time period and/or up to a time when it is made available, or feeds electrical energy into the power supply system.

5. Method according to claim 1, having a field bus by which the controller is connected to the battery management systems and/or to the inverter and/or rectifier.

6. Method according to claim 1, wherein 3, 4, 5, 8 or 10 battery units are connected electrically in series in the battery chain.

7. Method according to claim 1, wherein each battery unit has a rated voltage of ≧250V and ≦1 kV.

8. Method according to claim 1, wherein the inverter and/or rectifier has on the battery chain side a rated voltage of ≧1 kV and ≦5 kV.

9. Method according to claim 1, wherein the power supply system side has a rated voltage of ≧10 kV and ≦30 kV.

10. Method according to claim 1, having a shelf system comprising at least two shelves, at least two battery chains and a loading device, wherein each battery chain is arranged on a respective shelf, and the loading device is configured to automatically insert the battery unit into the shelf, or remove said battery unit therefrom, and to electrically disconnect or connect the battery unit to the battery chain and/or lock said battery unit to the shelf.

11. Method according to claim 10, comprising a device configured to perform input control, output control and/or end-of-line testing of the battery unit.

12. Method according to claim 1 and having the step: exchanging all the battery units of each battery chain at the latest after an energy throughput of the battery chain of ≦2000 kWh.

13. Method according to claim 1 and having the step: charging the battery unit during times of favourable electricity costs.

14. Method according to claim 1 and having the step: charging and/or discharging the battery unit in order to compensate for performance system fluctuations of the power supply system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 shows a schematic illustration of the intermediate storage facility according to a preferred exemplary embodiment of the invention, and

[0026] FIG. 2 shows a flow chart relating to the equipment of the intermediate storage facility.

[0027] FIG. 1 shows a schematic illustration of an intermediate storage facility 1, also referred to as a battery production store, with a central controller 2 and a multiplicity of battery chains 6 with a rectifier and/or inverter 11 and battery units 3 with interfaces 9 and 10 for connecting the battery units 3.

DETAILED DESCRIPTION OF THE DRAWINGS

[0028] The battery units 3 each have a battery cell 31 and a battery management system 32. In FIG. 1, in each case three battery units 3 are connected electrically in series to form a battery chain 6 via energy transmission interfaces 9 and energy transmission lines 4. The transmission lines 4 of the two battery chains 6 are connected to the inverter and/or rectifier 11, which is in turn connected via further energy transmission lines, indicated in FIG. 1, to a power supply system 14.

[0029] Each battery unit 3 also has a signal interface 10 by means of which the battery management system 32 is connected via a field bus 5 to the controller 2, as is illustrated indicatively in FIG. 1. The battery management system 32 can be used to determine internal operating states of the respective battery unit 3, for example by means of a current sensor, voltage sensor, or temperature sensor, in order to transmit to the controller 2 information about the state of charge of the respective battery cell 31, an identifier of the respective battery unit 3 to a storage location of the battery unit 3 in the intermediate storage facility 1 or fault information about faults which have occurred. Alternatively, instead of a field bus connection 5 a radio link can be provided from each of the battery units 3 to the central controller 2, in order to transmit the corresponding information and to centralize it in the central controller 2.

[0030] A total of 6 shelf locations 36 for respectively accommodating a battery unit 3 are illustrated in FIG. 1. In order to demonstrate the method of functioning, battery units 3 of the battery chain 6, illustrated on the left in FIG. 1, are inserted into the shelf locations 36, but the energy-transmission interfaces 9 and signal interfaces 10 of the battery units 3 are not yet electrically connected to the corresponding energy-transmission interfaces 9 and signal interfaces 10 of the left-hand battery chain 6. In the shelf location 36, illustrated at the bottom in FIG. 1, of the right-hand battery chain 6 the energy-transmission interface 9 and signal interface 10 of the battery unit 3 are connected to the battery chain 6. In the shelf location 36 which is shown at the top in FIG. 1, a battery unit 3 is inserted by means of a loading device 15 which is described in more detail below.

[0031] The central controller 2 has an external communication interface (not shown) for receiving and/or outputting information, which communication interface is connected, for example, to a central control station of a performance system operator of the power supply system 14. The external communication interface can be a wire-bound performance system connection, a radio link and/or a field bus connection. Load requirements and demand figures for battery units 3 from the production facility, as well as control performance requirements and current electricity prices from the control station of the performance system operator. Furthermore, the central controller 2 can also receive and store performance and energy forecasts of the connected battery chains 6. The controller 2 is primarily designed to control the current of the battery chain 6 across the inverters and/or rectifiers 11. The current which is to be adjusted by the controller 2 can be selected and interrupted in accordance with a load curve or by means of electricity price information.

[0032] The inverter and/or rectifier 11 is of bidirectional design, with the result that, on the one hand, electrical energy can be transmitted from the power supply system 14, via a performance system transmission terminal 22, the further transmission line, via a coupling element 18, a fuse device 25 and the energy transmission line 4, to the connected battery unit 3 in order to charge it, and, on the other hand, electrical energy can be transmitted in the opposite direction back into the power supply system 14 from the battery units 3. The central controller 2 also has a microprocessor which is connected to the field bus 5 via a communication interface. The control unit serves to monitor the flow of energy from and to each battery chain 6 via the inverters and/or rectifiers 11 and the battery interfaces 9, and to control the inverters and/or rectifiers 11 in accordance with a storage and energy provision function in such a way that load optimization is carried out.

[0033] The central controller 2 can also detect individual states of the inverter and/or rectifier 11 and detect differences in the loads, overloads and faults in the individual battery chains 6. If the loads of the battery chains 6 and of the battery units 3 are too large, the central controller 2 can decide to carry out compensation of the loads of the battery chains 6 by means of corresponding instruction via the field bus connection.

[0034] The control unit is also provided with a planning function with permits an availability time of the battery chains 6 to be defined as a function of the instantaneous state of charge of a connected battery chain 6, the time for which the battery unit 3 has been in the battery chain 6, the extracted current and the load request. For this, information about the use profile, the serial numbers and the battery chain membership, storage location and the state of charge of the used battery units 3 for each battery chain 6 is available to the control unit and, stored there. With this information, battery chains 6 with their battery units 3 can be available for as long as possible for optimizing the energy load. In an analogous fashion, if it is known that a specific battery chain 6 with battery units 3 is no longer required for load optimization, information can be made available to the production facility via the central controller 2, so that the corresponding battery units 3 can be picked up for the production facility or for delivery and replaced with new battery units 3.

[0035] Referring to the flowchart in FIG. 2, the functions of the intermediate storage facility 1 will be described in more detail below. The intermediate storage facility 1 is embodied as a shelf system with inserts for battery units 3 and a plurality of energy transmission interfaces 9 and 22 for the serial connection of the battery units 3 to form battery chains 6 and to the power supply system 14 with a plurality of inverters and/or rectifiers 11.

[0036] The connection of the battery units 3 can be carried out manually as well as in an automated or partially automated fashion with the loading device 15, with the result that when the battery units 3 are inserted into the corresponding shelf location 36, the connections 9 and 10 are made automatically. In this way, the intermediate storage facility 1 can be operated not only at reaching height or ladder heights but also in high-rack storage arrangements. In the first step, safety devices such as locks, access locks, states of the battery chains 6 and the inverter and/or rectifier 11 are interrogated. Then, information from unused and released battery chains 6 as well as the battery units 3 contained therein is communicated to the production facility via the communication interface and the field bus 5. The controller 2 receives demand information about required energy and performance from the production facility or the performance system operator and the required number of battery units 3 for the production facility either by inputting at a user interface (not shown) or via the external communication interface and the field bus 5.

[0037] The demand information indicates essentially what performance and energy is required by the production facility or the performance system operator, and how many battery units 3 are required at what times in the production facility. The control unit determines the available and transmissible performance and quantity of energy as a function of the number of connected battery chains 6, performance capability of the inverters and/or rectifiers 11, and the performance information and states of charge of the battery units 3 connected in the battery chain 6. Furthermore, the controller 2 compares the available performance and energy and the number of released battery units 3 and free locations 36 with the requirements of the production facility and of the performance system operator as well as with the electricity price for the charging of the battery units 3.

[0038] The required battery chains 6 which can be connected to the power supply system 14 via the inverter and/or rectifier 11 within a time specified by the demand information are correspondingly selected in the next step in accordance with the demand information, so that the performance and energy requirement can be met. Additionally required battery chains 6 are connected, and battery chains 6 which are not required are disconnected and released. Battery units 3 which are to be made available in accordance with the demand information are selected and released, according to their serial number, storage date and ageing as a result of use. The selection is prioritized in accordance with the period of storage, ageing and the use profile as well as the lowest state of charge. The sequence and therefore the earliest provision period for a battery chain 6 are calculated from the previously described parameters and values.

[0039] For the other battery chains 6 which are connected and selected, the energy and performance is made available in accordance with the demand requirements and fed in to the power supply system 14. As a result of the short storage time, charging and storage which are beneficial for the service life are not necessary, since the battery units 3 are continuously replaced by new ones and are not stored or used for a long time during ongoing production. In the last step, the system waits for new demand information, or new demand information from the history of the load distribution, in particular of the production facility, is automatically also taken into account and stored in the controller. If new demand information is available, this is the case—alternatively: yes, the system jumps back to the step of the interrogation of the states of the battery chain.

LIST OF REFERENCE NUMBERS

[0040] 1 Intermediate storage facility [0041] 2 Central controller [0042] 3 Battery unit [0043] 4 Energy-transmission line [0044] 5 Field bus [0045] 6 Battery chain [0046] 9 Energy transmission interface [0047] 10 Communication unit with interface [0048] 11 Inverter or rectifier [0049] 14 Power supply system [0050] 15 Loading device [0051] 18 Coupling element [0052] 25 Fuse device [0053] 31 Battery cell [0054] 32 Battery management system [0055] 36 Shelf location