AT515676B1 - A rechargeable battery system and method for controlling the charging of a rechargeable battery system - Google Patents

Abstract

A rechargeable battery system (100) is described in which performance consideration is possible to assess when and when a rechargeable battery (32) of the battery system (100) can not be charged. Several such battery systems (100) may preferably be combined in a cascade.

Description

description

RECHARGEABLE BATTERY SYSTEM AND METHOD FOR CONTROLLING THE CHARGING OF A RECHARGEABLE BATTERY SYSTEM

The present invention relates to a rechargeable battery system for supplying electrical consumers of any kind, in particular of mobile electrical consumers, as well as a suitably ausgestaltetes method for controlling the charging of a rechargeable battery system. In particular, the present invention relates to such a rechargeable battery system, which is particularly simple and flexible expandable, so as to be able to provide a variable supply voltage for the respective electrical load depending on the extension of the battery system.

In most conventional rechargeable battery systems for supplying mobile consumers, the respective battery is integrated in the consumer. Some battery systems include an external rechargeable battery, in which battery systems only a single rechargeable battery can be connected simultaneously. The user must choose a certain size of battery, i. in order to achieve a longer operating time of the respective consumer, either a larger battery would have to be selected or the battery would have to be changed after a part of the operating time.

Rechargeable battery modules can also be interconnected by means of a communication bus to control the charging or discharging of the battery modules. However, if the individual battery modules can not communicate with each other or, for example, should not communicate for reasons of cost, there are only a few ways to implement a controller whether to charge or discharge or if there is enough power to simultaneously charge all the battery modules. One known possibility is a control over the voltage; If too many battery modules are connected in parallel and are to be charged at the same time, the voltage of the charge source for the battery modules can go down so low that the battery modules can only charge slower, thus reducing the total power consumption or overloading the charging source.

An object of the present invention is to provide a rechargeable battery system, which is simple and flexible expandable while avoiding the problems described above. In particular, it is an object of the present invention to provide a flexibly expandable rechargeable battery system wherein overloading of a charge source for charging the battery modules is prevented and simultaneous or sequential charging of as many battery modules at maximum speed is possible as the charging power of the existing charging source permits without the need for communication between the battery modules. Furthermore, it is an object of the present invention to propose a correspondingly configured method for controlling the charging of a rechargeable battery system.

These objects are achieved by a rechargeable battery system with the features defined in claim 1 and a method having the features defined in claim 17. The dependent claims define preferred or advantageous embodiments of the invention.

The battery system according to the invention comprises a first terminal or input terminal for receiving an input voltage, a second terminal or output terminal for outputting an output voltage, and a rechargeable battery connected between the input terminal and the output terminal. In addition, a current measuring device is provided for measuring a current flowing from an electrical contact of the input terminal to an electrical contact of the output terminal, wherein a control device controls a charging of the rechargeable battery on the basis of the input voltage depending on the current measured by the measuring device. The control device may include a controller, for example in the form of a microcontroller, which determines depending on the detected current, whether a charging electronics of the battery system can be unlocked to charge the rechargeable battery.

The battery system is preferably capable of supplying or charging an electrical load alone, or interconnected with other identical battery systems in the form of a larger battery assembly to power or charge an electrical load. Charge and supply is also possible at the same time.

The current measuring device may comprise a connected between the electrical contact of the input terminal and the electrical contact of the output terminal measuring resistor, wherein the control device is preferably configured such that it evaluates a voltage drop across the measuring resistor voltage to depend on the charging of the rechargeable battery Taxes.

Preferably, the controller is configured to cause charging of the rechargeable battery if the current measured by the current measuring device is below a threshold. In particular, with sufficient voltage and no or relatively little current flow, the battery is charged as fast as possible, while with a relatively large current flow, i. a current flow that exceeds a corresponding threshold, no charge occurs.

According to a further preferred embodiment, the battery with a lower power than the maximum charging power, i. at a slower speed, charged if the measured current indicates that the charging source is not yet fully utilized, but there is not enough power left to charge the battery at full speed, i. when the measured current is between a corresponding lower threshold and a corresponding upper threshold.

The rechargeable battery may be coupled via a switching device, which may be realized for example by switches and / or diodes, with the input terminal and / or the output terminal, wherein the switching device is configured such that it depends on the input voltage at the input terminal or optionally depending on the output voltage at the output terminal blocks or passes. In this way it can be ensured that the voltage is maintained by the battery when falling below the voltage at the respective terminal.

The battery system may be configured such that it is irrelevant whether a supply voltage is applied to the first terminal or to the second terminal, since the battery system works in both directions, i. E. both at a current flow from the first terminal to the second terminal and at a current flow from the second terminal to the first terminal. As " input terminal " For the purposes of the present invention, the connection to which the input voltage is applied is thus understood in each case, while the " output connection " denotes that terminal which provides the output voltage.

The battery system can have a communication port for communication with a further battery system, a charging source, which provides the input voltage for the battery system, and / or to be supplied with the output voltage of the battery system to electrical consumers, the communication port are used in particular can tell the battery system, the power of the charging source or the type of Ladeqelle. If the power of the charging source is known, the controller of the battery system can control the charging of the rechargeable battery depending thereon.

Alternatively or additionally, the battery system by means of a voltage measuring device, the respectively applied to the input terminal voltage, i. the charging voltage, capture and depending on the type or the power of the charging source close.

The battery system according to the invention can be cascaded with other battery systems of the same type to form a battery assembly, so that flexible by a user, the capacity of the battery assembly thus formed can be adapted to the particular needs or consumers.

The present invention thus provides a way to cascade several battery systems according to the invention, whereby an overload of a charging source provided for charging the battery systems or the corresponding batteries is prevented and a simultaneous or sequential charging of so many battery systems with full potential Charging speed is possible as this corresponds to the available charging power. In particular, no communication between the individual battery systems is required.

In the context of the present invention, a method for controlling the charging of a rechargeable battery of a battery system, which has a first terminal or input terminal for receiving an input voltage and a second terminal or output terminal for outputting an output voltage, is thus also proposed the steps of measuring a current flowing from an electrical contact of the input terminal to an electrical contact of the output terminal, and controlling the charging of the rechargeable battery based on the input voltage depending on the measured current.

The method is carried out in particular automatically by the control device of the previously described battery system according to the invention.

The invention will be explained below with reference to preferred embodiments with reference to the accompanying drawings.

Figure 1 shows a battery system according to a first embodiment of the inven tion.

FIG. 2 shows a battery system according to a second exemplary embodiment of the invention.

Figure 3 shows a cascade-like interconnection of several battery systems of the present invention to a larger battery system or a battery assembly with a charging source and an electrical load.

Fig. 1 shows a rechargeable battery system 100, which is designed in particular in the form of an integrated circuit in a housing of a battery module or battery pack. The illustrated battery system 100 includes an input terminal having a live input pin 11 and a grounding input pin 12, to which an input or charge voltage of a load source or supply voltage source (not shown) is to be applied to the input terminal.

As shown in Fig. 1, between each pin or contact of the two terminals, in particular between the two live pins 11, 13, a measuring resistor or shunt resistor 21 is connected, which realizes the function of a current measuring device together with a voltage measuring device 22 , The voltage dropping across the measuring resistor 21 is detected by the voltage measuring device 22 and evaluated by a controller 40, which can be realized, for example, by a microcontroller, in order thus to determine the current through the measuring resistor 21.

Between the input terminal and the output terminal, a rechargeable battery or a rechargeable battery is connected, which can optionally be charged or not charged depending on the input voltage applied to the input terminal by means of a charging electronics 31.

The rechargeable battery 32 is coupled via a diode 27 to the live pin 13 of the output terminal, while the charging electronics 31 is coupled via a controllable switch 25 to the live pin 11 of the input terminal. The switch 25 and the diode 27 are merely exemplary of the function of a corresponding switching device, which selectively blocks or directs. Thus, both components 25, 27 can be realized by controllable switches or diodes or by other similarly acting components. In the illustrated embodiment, the controllable switch 25 is used in particular for switching on the charging electronics, while the diode 27 is used to supply the consumer to be coupled to the output terminal.

The operation of the illustrated battery system 100 is as follows.

The controller 40 determines, depending on the measured current through the measuring resistor 21, whether the charging electronics 31 can be unlocked by closing the switch 25 to charge the battery 32.

With sufficient voltage and no or a relatively low current flow through the measuring resistor 21, the controller 40 controls the charging electronics 31 so that the battery 32 is charged. Preferably, the battery is charged as fast as possible in this case. A relatively low current flow in this sense is understood to mean a threshold value at which the power of the respective charging source is sufficient to charge the battery 32 of the battery system 100 in addition to the electrical power that flows through the battery system 10. If a current flows through the measuring resistor 21, which is not consumed by the battery system 100 itself, the controller 40 assumes that either an electrical consumer is connected to the output terminal or at least one further battery system is connected downstream, which is also charged.

If a certain upper threshold in the current flow is reached, the known power of the charging source is no longer sufficient to charge the battery system 100 at all, and it must therefore be no charge. As a result, the controller 40 deactivates the charging electronics 31 by opening the switch 25 when the current through the sensing resistor 21 reaches or exceeds an upper threshold. This threshold may differ from the former threshold, but in principle it is also conceivable to work with only one threshold.

Preferably, however, the two mentioned thresholds are different, wherein at a current through the measuring resistor 21, which is between the two thresholds, the controller 40, the charging electronics 31 controls such that the battery 32 with a lower power or with a lower Speed as the maximum possible power or speed is loaded. This means that the charging electronics 31 is driven to charge the battery 32 with less power than the maximum charging power when the power is in a range in which the charging source is not fully utilized, but also not enough power reserve is available, to charge the battery 32 at full speed.

As shown in Fig. 1, the battery 32 may be connected by means of a controllable switching device or diode with at least one pin of a terminal, that when the voltage falls below the voltage at the respective pin, the voltage is maintained by the battery 32. Thus, if no charge voltage more, the voltage is maintained by the battery 32 on. In Fig. 1, for example, only the diode 27 is shown for the live pin or contact 13 of the output terminal. Of course, however, a corresponding switching device or diode can also be provided for the other pins or for the input connection.

Fig. 2 shows an alternative embodiment of the battery system 100, in which the function of the diode 27 is taken over by a controllable switch 26, wherein the switch 26 is selectively closed or opened depending on the voltage applied to the output terminal voltage.

As shown in FIG. 2, the battery system 100 may additionally be equipped with at least one communication pin 15 or a communication port. According to the invention as described, the current flow is detected by the measuring resistor 21 and determined in dependence on the measured current flow, whether the charging electronics 31 can be unlocked to charge the battery 32. The controller 40 of the battery system 100 must be aware of what power the charging source has available. If the type of charging source is always the same, the charging power of the controller 40 is known. If the charging power is not known, however, the type of charging source or the corresponding charging power of the controller 40 can be communicated via such a communication port. In general, the communication connection 15 can be used for communication of the battery system 100 with other battery systems, with the charging source or with the respectively connected electrical consumer.

To realize a switching between different power levels, both in Fig. 1 and in Fig. 2, a voltage measuring device 23 is provided which detects the voltage applied to the input terminal 11, 12 charging or input voltage and forwards to the controller 40. If the input voltage is below a certain threshold (for example of the order of 20V), the controller 40 assumes that a particular type of charging source with a given charging power (for example of the order of 24W) is present, while if the threshold is exceeded another charging source type is present a correspondingly higher charging power (for example of the order of 75W) is assumed. Depending on the respectively assumed charging power, the charging electronics 31 are controlled accordingly by the controller 40.

In Fig. 3 by way of example a cascade-like interconnection of several battery systems 100, 200, 300 according to the invention is shown in order to realize a battery arrangement with a desired capacity.

The first battery system 100 is connected on the input side to a charge source 1 designed, for example, as a charger, while the output terminal of the first battery system 100 is connected to the input terminal of the second battery system 200. The output terminal of the second battery system 200 is in turn connected to the input terminal of the third battery system 300, which on the output side supplies an electrical load 2 with a desired supply voltage.

The voltage provided by the charging source 1 is passed through the three battery systems 100, 200 and 300 and arrives at the consumer 2. The voltage drop through the measuring resistors 21 is very small. Each battery system 100, 200 and 300 observed the current through its measuring resistor 21. If, for example, the charging source 1 delivered a maximum charging power of 200W, the consumer 2 would only need a power of 50W and each battery system could charge its battery 32 with a maximum of 100W each Thus, the consumer 2 would receive a power of 50W. The last battery system 300 would recognize, by means of its measuring resistor 21 and its voltage measuring device 23, that a power of 50W would be passed through the battery system, and would switch on the charging electronics 31 at full power with a corresponding state of charge of its battery 32. As a result, a power of 200 W would be measured in the battery system 200 by means of its measuring resistor 21 and its voltage measuring device 23. Depending on the ability of the charging electronics 31 now with half power or -the charging electronics 31 would not be able - not charged. Only when the battery system 300 has fully charged its own battery 32 would the battery system 200 be able to charge at full power. The battery system 100 could accordingly charge later at full power, namely, only when the batteries 32 of the battery systems 200 and 300 are fully charged. The chain is loaded, so to speak, from back to front.

Of course, with sufficient power of the charging source 1, all battery systems 100-300 could charge simultaneously at full power. Likewise, no consumer 2 could be connected, so that only the battery systems 100-300 are charged by means of the charging source 1.

It could also be connected to any charging source 1, and all battery systems 100-300 could supply only one or more consumers 2. In this case, in the embodiment with diodes shown in FIG. 1, the battery system with the strongest battery 32 would contribute the most to the supply. For equally charged batteries 32, the last battery system 300 in the chain 300 would contribute slightly more than the front battery systems 100, 200 for supplying the load 2 due to the voltage drops across the measuring resistors 21.

The battery system described above works in both directions. The plugs of the terminals 11,12 and 13, 14 may be made identical, and to both terminals both a charging source and an electrical load can be connected. The controller 40 may consider the amount of current through the sense resistor 21 and take it into account when calculating the power. If a charging source 1 is connected, for example, to the connection 11, 12, then the current consumed by the battery system 100 of the charging electronics 31 does not flow through the measuring resistor 21, but if the charging source 1 were connected to the connection 13, 14.

Claims (19)

Claims 1. A battery system (100) comprising an input terminal (11, 12) for receiving an input voltage, an output terminal (13, 14) for outputting an output voltage, one between the input terminal (11, 12) and the output terminal (13, 14). switched rechargeable battery (32), a current measuring device (21) for measuring a current flowing from an electrical contact of the input terminal (11, 12) to an electrical contact of the output terminal (13, 14) current, and a control device (31, 40) which is configured to control a charging of the rechargeable battery (32) based on the input voltage depending on the current measured by the measuring device (21). 2. Battery system (100) according to claim 1, characterized in that the current measuring device comprises a between the electrical contact of the input terminal (11) and the electrical contact of the output terminal (13, 14) connected measuring resistor (21). 3. Battery system (100) according to claim 2, characterized in that the control device (31, 40) is designed such that it evaluates a voltage drop across the measuring resistor (21) in order to depend on the charging of the rechargeable battery (32) Taxes. 4. Battery system (100) according to any one of the preceding claims, characterized in that the electrical contact of the input terminal (11, 12) and the electrical contact of the output terminal (13, 14) is in each case a live electrical contact. 5. Battery system (100) according to one of the preceding claims, characterized in that the battery system is designed in the form of a unit integrated into a housing of a battery module. 6. Battery system (100) according to any one of the preceding claims, characterized in that the control device (31,40) is designed such that it causes a charging of the rechargeable battery (32), if the current measured by the current measuring device (21) is a threshold. 7. Battery system (100) according to any one of the preceding claims, characterized in that the control device (31, 40) is designed such that it does not charge the rechargeable battery (32), if the measured by the current measuring device (21) current over a Threshold is. 8. Battery system (100) according to any one of the preceding claims, characterized in that the control device (31,40) is designed such that it causes a charging of the rechargeable battery (32), if the current measured by the current measuring device (21) is a first threshold while not charging the rechargeable battery (32) if the current measured by the current measuring device (21) is above a second threshold greater than the first threshold. 9. Battery system (100) according to any one of the preceding claims, characterized in that the control device (31,40) is designed such that it causes a charging of the rechargeable battery (32) at a first charging speed, if the of the current measuring device (21 ) is below a first threshold while causing the rechargeable battery (32) to charge at a second charging rate if the current measured by the current measuring device (21) is between the first threshold and a second threshold greater than the first threshold is, wherein the second charging speed is less than the first charging speed. 10. Battery system (100) according to one of the preceding claims, characterized in that the rechargeable battery (32) via a switching device (27) to the input terminal (11, 12) and / or the output terminal (13, 14) is coupled, wherein the switching device (27) is designed such that it selectively blocks or conducts depending on the input voltage at the input terminal (11, 12) or depending on the output voltage at the output terminal (13, 14). 11. Battery system (100) according to claim 10, characterized in that it comprises switching means (25-27) a controllable switch (26) and / or a diode (27). 12. Battery system (100) according to any one of the preceding claims, characterized in that a communication port (15) for communication with a further battery system (200, 300), a charging source (1), which provides the input voltage for the battery system (100) represents, and / or is provided with the output voltage of the battery system to be supplied electrical load (2). 13. Battery system (100) according to claim 12, characterized in that the communication port (15) is provided for the transmission of information about an available power of the charging source (1) to the battery system (100). 14. Battery system (100) according to one of the preceding claims, characterized in that the battery system (100) comprises a voltage measuring device (23) for measuring the voltage applied to the input terminal (11, 12) input voltage. 15. Battery system (100) according to claim 14, characterized in that the control device (31,40) is configured such that, depending on the voltage measured by the voltage measuring device (23) voltage an available power of a charging source (1), which the input voltage provides and determines depending on the charging of the rechargeable battery (32) controls. 16. A battery assembly comprising a first battery system according to claim 1, and a second battery system according to claim 1, wherein the output terminal of the first battery system is connected to the input terminal. 11, 12) of the second battery system (200) so that the first battery system (100) provides at its output terminal the input voltage to the second battery system (200). 17. A battery assembly according to claim 16, characterized in that the input terminal (11, 12) of the first battery system (100) with a charging source (1) is connected, and that the output terminal (13, 14) of the second battery system (200) with a electrical consumer (2) or the input terminal (11, 12) of a further battery system (300) is connected according to one of claims 1-15. 18. A method of controlling a charging of a rechargeable battery (32) of a battery system (100) having an input terminal (11, 12) for receiving an input voltage and an output terminal (13, 14) for outputting an output voltage, comprising the steps of: measuring a current flowing from an electrical contact of the input terminal (11, 12) to an electrical contact of the output terminal (13, 14), and controlling the charging of the rechargeable battery (32) based on the input voltage depending on the measured current. 19. The method according to claim 18, characterized in that the method is performed automatically by the control device (31, 40) of the battery system (100) according to any one of claims 1-15. For this 3 sheets of drawings