High-voltage battery system

Abstract

The present invention relates to a high-voltage battery system (1) for storing electrical energy in a number of electrically interconnected elementary storage cells (4) that are under monitoring and control by way of a battery management system (7) via an analogue line and / or a data line (6) and, when the interconnected elementary storage cells (4) are electrically connected, via high-voltage paths (5) with circuit breakers (8) in a high-voltage distributor box (9) towards external high-voltage terminals (10). In order to provide a high-voltage battery system that is easier to transport and construct with an adjustable capacity, it is proposed that the high-voltage battery system (1) comprises a base system (2), has in the base system (2) at least one node (3) to an essentially electrically identical subsystem (12), wherein the node (3) is formed as an interface for an analogue line (6) and / or a data line of the subsystem (12) to the battery management system (7) of the base system (2) and as an interface for a high-voltage path (5) of the subsystem (12), and a subsystem (12) itself comprises essentially only one interconnected module (Mod).

Description

[0001] High-voltage battery ©system

[0002] The present invention relates to a high-voltage battery system for storing electrical energy in a number of interconnected elementary storage cells under monitoring and control by a battery management system with electrical connection of the interconnected elementary storage cells via circuit breakers in a high-voltage distribution box to external high-voltage connections.

[0003] Various approaches to constructing a high-voltage battery system of the type mentioned are known from the state of the art, which are listed as stationary systems in the case of very high capacities.

[0004] Most high-voltage battery systems are housed in a container and have a gateway that controls parallel-connected sub-battery systems. This has the disadvantage that conventional high-voltage battery systems are very massive, heavy, and cumbersome to transport and install. However, demand for stationary high-voltage battery storage systems of various sizes and electrical capacities for grid stability or as emergency power generators is constantly increasing. Currently, there are few scalable applications for such stationary high-voltage energy storage systems with high capacities. Without a suitable new development, standard sizes must be used.

[0005] It is the object of the present invention to create a high-voltage battery system which is easier to transport and assemble while having an adaptable capacity. This object is achieved according to the invention by the features of claim 1 in a high-voltage battery system for storing electrical energy in a number of interconnected elementary storage cells which are connected via an analog line and / or a data line under monitoring and control by a battery management system and have an electrical connection of the interconnected elementary storage cells via high-voltage paths with power switches in a high-voltage distribution box to external high-voltage connections, in that the high-voltage battery system comprises a basic system in which at least one node to a substantially electrically similar sub-system is provided,which is designed as an interface for an analog line and / or a data line of the subsystem to the battery management system, as well as as a connection for a high-voltage path of the subsystem, and a subsystem itself essentially comprises only interconnected modules. Thus, the total capacity of a high-voltage battery system can be more easily scaled across a number of subsystems in specified font sizes. This adaptation of the total capacity of a high-voltage battery system according to the invention can be carried out by connecting one or more subsystems to the node in the base system with a reduced number of battery management systems.

[0006] The present invention is based on the finding that, even in high-voltage battery systems, scalability by connecting at least one sub-system also significantly simplifies the mechanical requirements for transport, construction and on-site installation of a high-voltage battery system consisting of several units. The basic system forms a first unit and is capable of operating on its own as a high-voltage battery system with a specific electrical capacity and power. A sub-system which is essentially electrically similar to this basic system, preferably in the form of a standardized module, likewise simplifies the scalability of a high-voltage battery system according to the invention in two respects: systems with essentially similar electrical properties are also essentially the same and require essentially the same space and the same operating conditions.This is a significant advantage when selecting electrical components, but also with regard to mechanical fixing and cooling. At the same time, however, a sub-system also accesses resources of the base system that are not available in the sub-system: The sub-system is connected to the battery management system of the base system via an interface for an analog line and / or a data line. This means that the sub-system does not have its own, separate battery management system, among other things. Due to the electrically configured similarity to the interconnection of elementary storage cells in the base system, the sub-system can also be monitored and controlled by the battery management system of the base system. The sub-system can therefore be regarded as a passive system, at least from a control engineering perspective, while the base system can be regarded as an active system.In this case, the at least one sub-system can be arranged spatially separated from the base system, so that in a preferred embodiment of the invention a distributed structure is obtained from at least one base system and at least one sub-system electrically connected thereto.

[0007] Advantageous further developments are the subject of the dependent claims. Accordingly, the node is provided in the area of ​​the high-voltage distribution box of the basic system. The high-voltage distribution box can thus be further expanded as a center for various interfaces with little effort. In an advantageous further development of the invention, the interface for the high-voltage path of the sub-system is designed as a parallel circuit. The electrical similarity of the basic system to the at least one sub-system thus lies at least in a common voltage level in the area of ​​the node.

[0008] In a further development of the high-voltage battery system according to the invention, a current measuring point is provided in the high-voltage path of the subsystem, which, in one exemplary embodiment of the invention, is arranged upstream of the node. The current measuring point is preferably designed as a low-loss, compact Hall sensor.

[0009] In an advantageous development of the invention, the interface for the high-voltage path and / or the analog line and / or the data line of the sub-system are designed as a plug in the node.

[0010] The interface for the high-voltage path and / or the analog line and / or the data line of the sub-system in the node are preferably designed as an electro-mechanical connection with a plug.

[0011] In an advantageous further development, the subsystem connector incorporates the interface of the high-voltage path and the low-voltage path in a common housing. This provides a secure and compact design for a reliable electrical connection of the subsystem to the node of the base system.

[0012] In a preferred development, a device according to the invention has an advantageous securing means in that the plug of the sub-system comprises a switch by means of which the plug of the high-voltage path can only be released when the node is mechanically secured in place.

[0013] Preferably, a high-voltage battery system according to the invention comprises a sub-system with a series connection of elementary storage cells, contactors as switches in the high-voltage path, a fuse and preferably an economizer for internal coil current control of the contactors as an alternative to external pulse width modulation or PWM control.

[0014] In a further development of the invention, a low-voltage supply from circuit breakers or contactors of the subsystem is routed via the switch in the connector of the high-voltage path. This ensures that a high-voltage connector remains de-energized and potential-free until a mechanically secure electrical connection of the connectors in the node is established.

[0015] Further features and advantages of embodiments of the invention are explained in more detail below with reference to exemplary embodiments based on the drawings. In these, a schematic representation shows:

[0016] Figure 1: a circuit diagram of a first embodiment of a high-voltage battery system as a basic system with at least one node;

[0017] Figure 2: a circuit diagram of a second embodiment of a high-voltage battery system as a basic system with a node comprising two interfaces;

[0018] Figure 3: a circuit diagram of an embodiment of a sub-system and Figure 4: a block diagram of an embodiment of a scalably expandable high-voltage battery system using basic systems and sub-systems connected to them.

[0019] Throughout the various figures, the same reference numerals are used for the same elements or method steps. Without limiting the invention, only one use of a high-voltage battery system is illustrated and described below, which is particularly designed for stationary use as an emergency power system or compensation storage with large capacity. However, it is obvious to a person skilled in the art that an adaptation to the use of distributed energy storage in a vehicle on land, on water, or in the air is also possible, in particular using a cell-to-chassis approach.

[0020] Figure 1 shows a circuit diagram of a first exemplary embodiment of a high-voltage battery system 1 as a basic system 2 with at least one node 3. The high-voltage battery system 1 is designed to store electrical energy in a number of electrically interconnected elementary electrochemical storage cells 4, preferably lithium-ion cells of a cylindrical design, which in this exemplary embodiment are interconnected in the form of modules Mod. Here, 16 modules Mod are connected to one another in a series circuit. Each of the modules Mod is assigned its own cell monitoring circuit esc, as indicated by the identical counters. The cell monitoring circuit esc continuously monitors the respective module Mod via various sensors in order to create corresponding measurement and status data on this basis.Based on this data from the cell monitoring circuits esc, a higher-level control and regulation of the electro-chemical storage arrangement described so far takes place in a battery management system 7, or BMS for short. The Mod modules have an analog line 5 for transmitting electrical power and a data line 6 for sending data for control and monitoring to the battery management system 7, implemented here as a reversible isoSPI data line. The analog line 5 is designed as an electrical connection of the Mod modules from elementary storage cells 4 interconnected therein as a high-voltage path, which extends via circuit breakers 8 in a high-voltage distribution box 9 to an external high-voltage connection eHV con 10 for both polarities.

[0021] In addition to the battery management system 7, which operates at a low voltage level of 12 V, the high-voltage distribution box 9 includes the circuit breakers 8, which are connected to the battery management system 7 via an analog control line and are provided for each polarity, as well as a fuse F and a current measuring resistor SNT, which in turn is connected to the battery management system 7 via a reversible isoSPI data line 6. From the battery management system 7, the data line 6 runs on the high-voltage distribution box 9 to an external low-voltage connection eLV con 11 of the isoSPI bus.

[0022] The system described above and known from the prior art is now expanded as a basic system 2 for a scalable expansion of an electrical capacity by means of at least one node 3 on the high-voltage path 5, to which at least one essentially electrically similar sub-system 12 is connected. The node 3 is provided in the area of ​​the high-voltage distribution box 9 and has a connector 13 for a high-voltage path 5 of the sub-system 12 at the low-voltage level and also an interface for the data line 6 of the sub-system 12 to the battery management system 7 of the basic system 2, as described in more detail below.

[0023] In the present exemplary embodiment, the interface for connecting a high-voltage path 6 of the subsystem 12 to the high-voltage path 6 of the base system 2 is connected via a high-voltage connector 13 as a parallel circuit in node 3. Thus, in the present exemplary embodiment, two subsystems 12 can be connected or plugged into the base system 2 in the area of ​​node 3 in parallel.

[0024] Figure 2 shows a circuit diagram of a second exemplary embodiment of a high-voltage battery system as a basic system 2 with a node 3 comprising two interfaces or connectors 13. In an extension of the first exemplary embodiment, a current measuring point 14 is provided in the high-voltage path 5 of the basic system 12. The current measuring point 14 is arranged upstream of the node 3 to measure the individual strand currents and is designed as a Hall sensor. This means that the current flow in each of the up to two sub-systems 12 can be determined separately. This measurement data is transmitted to the battery management system 7 via a CAN, KI 15 or KI 30C data line 6 and is also forwarded to higher instances via a low-voltage connector eLV-con of the high-voltage distribution box 7.Thus, in a manner not further shown, a vehicle control unit VCU communicates with the battery management system 7 of the base system 2 and, via this battery management system 7, also with the sub-systems 12 each connected to the base system 2 via the node 3. The elimination of separate battery management systems 7 in the sub-systems 12 leads to significant cost savings, but limits the number of sub-systems 12 that can be connected to a base system 2 to two in the present embodiment. Therefore, no further connections for further parallel connections can be provided in the node 3 either.

[0025] Figure 3 shows a circuit diagram of an exemplary embodiment of a sub-system 12. The sub-system 12 itself essentially only comprises a series connection of 16 modules and thus corresponds in terms of electrical properties to one of the basic systems 2 described above. In terms of monitoring and control, however, the sub-system 12 is a passive system since it does not comprise its own battery management system BMS, but is instead monitored and regulated by the battery management system BMS of a basic system 2 to which it is connected. The high-voltage paths 5 have only one fuse F and two circuit breakers SW. In this exemplary embodiment, a connector 15 of the sub-system 12 comprises an interface for the high-voltage path 5 and the low-voltage path 6 in a housing.The connector 15 of the sub-system 12 comprises a switch 16 which is designed such that the high-voltage path 5 can only be activated when it is mechanically secured to the connector 13 of the node 3. For protection, a low-voltage supply from contactors SW of the sub-system 12 is led in the connector 15 via the switch 16. Each sub-system 12 therefore essentially only comprises an interconnected module Mod and therefore represents a pure extension of an electrical storage capacity without its own control and monitoring functionalities. With essentially the same size as a basic system 2, sub-systems 12 are therefore also cheaper than basic systems 2.

[0026] Figure 4 shows a block diagram of an exemplary embodiment of a scalable high-voltage battery system 1 that can be flexibly expanded to meet any given requirement. Serial and / or parallel interconnection of parts to the respective extent of several basic systems 2 was previously known. Now, each of the basic systems 2 can be expanded by one or two parallel-connected subsystems 12 using the nodes 3 described above, for the purpose of a gradual and scalable expansion of the electrical capacity of the high-voltage battery system 1. The outlined high-voltage battery system 1 can thus be expanded in partial steps, without additional circuitry and / or adaptation effort, even in the relevant basic systems 2.In this exemplary embodiment, a maximum expansion stage of a high-voltage battery system 1 is achieved with 16 basic systems 2 and two sub-systems 12 connected to each as rows #1 to #16. This allows for an overall system of (1 + 2) * 16 = 48 units with electrically similar storage behavior, each comprising 16 serially connected elementary electrochemical storage cells 4. However, in the maximum expansion stage outlined, this entire arrangement is reliably monitored and controlled by limiting it to 16 battery management systems 7.

[0027] The above describes a high-voltage battery system which, with its total capacity being adaptable via scaling in the form of subsystems 12, is easier to transport and assemble compared to known devices. Furthermore, according to a form according to the invention, stationary high-voltage energy storage devices with high capacities can be constructed more flexibly with easier handling of subsystems due to their different positioning. At the same time, the subsystems 12 are designed to be reduced in complexity by utilizing the control and monitoring functionalities of a respective base system 2 with secure and reliable interconnection via nodes 3, at least by eliminating the need for separate battery management systems. List of reference symbols: eHV-con external high-voltage connector eLV-con external low-voltage connector

[0028] Mod module esc cell monitoring circuit, each assigned to a module Mod

[0029] CON connector

[0030] F fuse

[0031] SHN current measuring resistor / shunt

[0032] SW switch

[0033] PCR precharge resistor

[0034] 1 high-voltage battery system

[0035] 2 Basic system

[0036] 3 knots

[0037] 4 elementary electro-chemical storage cell or module

[0038] 5 analog line / high-voltage path

[0039] 6 Data line / bus

[0040] 7 Battery Management System / BMS

[0041] 8 circuit breakers

[0042] 9 High-voltage distribution box

[0043] 10 external high-voltage connection

[0044] 11 external low-voltage connection to the isoSPI bus

[0045] 12 sub-systems

[0046] 13 Connector / connection area of ​​a sub-system 12 to the

[0047] Basic System 2

[0048] 14 electricity measuring point

[0049] 15 connectors of the sub-system 12 / CON

[0050] 16 Switch in the plug 15

Claims

Claims High-voltage battery system (1) for storing electrical energy in a number of electrically interconnected elementary storage cells (4), which are connected via an analog line and / or a data line (6) under monitoring and control by a battery management system (7) and have an electrical connection of the interconnected elementary storage cells (4) via high-voltage paths (5) with power switches (8) in a high-voltage distribution box (9) to external high-voltage connections (10), characterized in that the high-voltage battery system (7) comprises a base system (2), in which base system (2) at least one node (3) to a substantially electrically similar sub-system (12) is provided,wherein the node (3) is designed as an interface for an analog line and / or a data line (6) of the subsystem (12) to the battery management system (7) of the base system (2) and as an interface for a high-voltage path (8) of the subsystem (12), and a subsystem (12) itself essentially comprises only one interconnected module (Mod). High-voltage battery system (1) according to the preceding claim, characterized in that the node (3) is provided in the region of the high-voltage distribution box (9). High-voltage battery system (1) according to one of the preceding claims, characterized in that the interface for the high-voltage path (5) of the subsystem (12) is in the, The base system (2) is designed as a parallel circuit. The high-voltage battery system (1) according to one of the preceding claims, characterized in that a current measuring point (14) is provided in the high-voltage path (8) of the base system (2). The high-voltage battery system (1) according to the preceding claim, characterized in that the current measuring point (14) is arranged upstream of the node (3). The high-voltage battery system (1) according to one of the preceding claims, characterized in that the current measuring point (14) is designed as a Hall sensor. The high-voltage battery system (1) according to one of the preceding claims, characterized in that the interface for the high-voltage path (5) and / or the analog line and / or the data line (6) of the subsystem (12) in the node (3) are designed as an electromechanical connection with a plug (15).High-voltage battery system (1) according to the preceding claim, characterized in that the connector (15) of the subsystem (12) comprises a high-voltage path (5) and a low-voltage path for a data line (6) in a common housing. High-voltage battery system (1) according to one of the two preceding claims, characterized in that the connector (15) of the subsystem (12) comprises a switch (16) which is designed such that the connector (15) can only be released when the high-voltage path (5) is mechanically secured to the node (3). High-voltage battery system (1) according to one of the preceding claims, characterized in that a sub-system (12) comprises a series circuit of elementary storage cells (4), contactors as power switches (8) in the high-voltage path (5), and a fuse (F). High-voltage battery system (1) according to the preceding claim, characterized in that a subsystem (12) comprises an economizer. High-voltage battery system (1) according to the preceding claim, characterized in that a low-voltage supply from power switches (8) of the subsystem (12) is routed via the switch (16) in the plug (15) of the high-voltage path.

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