Battery pack, system comprising a battery pack and an electrical consumer and / or a charger, and method for operating a battery pack

Abstract

The invention relates to a battery pack (10a; 10b) with at least one connection interface (20a; 20b) for connection to an electrical consumer (14a; 14b), in particular an electric hand tool (16a; 16b), and / or to a charger, with a signal output unit (30a; 30b) which is configured to output at least one analog signal and at least one digital signal via at least one identical signal contact (34a; 34b) of the connection interface (20a; 20b). It is proposed that the signal output unit (30a; 30b) includes at least one electrical circuit (42a; 42b) which is configured to switch between a digital operating mode of the signal output unit (30a; 30b) and an analog operating mode of the signal output unit (30a; 30b).

Description

State of the art

[0001] A battery pack with a signal output unit, which is provided for analog data exchange via a signal contact, has already been proposed. Disclosure of the invention

[0002] The invention is based on a battery pack with at least one connection interface for connection to an electrical consumer, in particular an electric hand tool, and / or to a charger, with a signal output unit which is designed to output at least one analog signal and at least one digital signal via at least one same signal contact of the connection interface.

[0003] It is proposed that the signal output unit has at least one electrical circuit which is configured to switch between a digital operating mode of the signal output unit and an analog operating mode of the signal output unit.

[0004] The inventive design of the battery pack advantageously enables fast data transmission via a sensitive interface that is advantageously robust against electrostatic discharges and / or has high electromagnetic compatibility. This advantageously provides the safest and most efficient operation of the battery pack's energy storage device. Furthermore, a battery pack can advantageously be provided that is designed for both digital data exchange and analog data exchange, in particular via a connection interface.Furthermore, the signal contact can advantageously provide an analog and / or digital interface, which is advantageously backward compatible, in particular with analog electrical loads, preferably with an analog interface, particularly preferably with old electrical loads, and / or forward compatible, in particular with digital electrical loads, preferably with a digital interface, particularly preferably with newly developed electrical loads. In this case, adding a digital switching unit can advantageously ensure that old battery packs remain compatible with new electrical loads and / or chargers, and that old electrical loads and / or chargers remain compatible with new battery packs.

[0005] In particular, the battery pack has at least one energy storage device. The battery pack, in particular the energy storage device, has at least one battery cell, preferably a plurality of battery cells for storing electrical energy. The battery pack, in particular the energy storage device, is not limited to a specific battery cell type; rather, battery cells of the battery pack can be designed, for example, as lithium-ion cells and / or as lithium polymer cells and / or as nickel-cadmium cells and / or the like. Likewise, the battery cells of the battery pack according to the invention are not limited to a specific geometry and / or format, but can have different cell geometries and / or cell formats and be designed, for example, as round cells, flat cells, pouch cells, or the like, without departing from the scope of the present invention.

[0006] In particular, the battery pack is provided for connection to at least the electrical consumer, in particular to the preferably cordless power tool, along the connection direction and in a connected state to a power supply of at least one unit, for example a drive unit and / or a display unit, of the electrical consumer, in particular of the power tool. The battery pack is not limited to use with a specific type of power tool, but can in principle be provided for connection to various power tools of different types. A power tool to which the battery pack can be connected can, for example, be, but is not limited to, a cordless screwdriver and / or a drill and / or a grinder and / or an electric saw, e.g.a jigsaw and / or a router and / or a hot glue gun and / or a blower and / or a multi-function tool and / or a polishing machine and / or a planer and / or a comparable handheld power tool. It is also conceivable that the battery pack is designed for alternating use with various power tools.

[0007] Preferably, the battery pack is provided for connection to at least the charger along the connection direction and, in a connected state, for charging the battery pack by an external power source. The charger preferably has an input terminal connected to the external energy source and an output terminal connected to the battery pack. In particular, the charger has a control and / or regulating unit that controls and / or regulates the charging processes, in particular setting a suitable charging method based on a state of charge, a nominal voltage, and / or a capacity of the battery pack.

[0008] The connection interface preferably serves as an electromechanical interface between the electrical consumer and / or the charger. The connection interface preferably has at least two power contacts configured for electrical connection to the charger and / or the electrical consumer, in particular to a connection interface of the electrical consumer and / or charger, in particular for discharging and / or charging. The connection interface of the battery pack preferably consists of contact tulips, which are inserted into one another as contact blades to connect to the connection interface of the electrical consumer and / or charger.

[0009] The connection interface preferably has at least the signal contact, which is particularly formed separately from the power contacts of the connection interface. The signal contact is preferably provided for signal transmission, in particular of the analog and digital signal, from the battery pack to the electrical consumer and / or charger, preferably to a corresponding signal contact of the electrical consumer and / or charger. Particularly preferably, the connection interface of the electrical consumer and / or charger has at least the signal contact corresponding to the signal contact.

[0010] Preferably, the signal output unit at least partially forms the signal contact or is at least partially built onto the signal contact. In particular, the digital signal is modulated onto an analog line. Preferably, the signal output unit has at least one signal output element, in particular a digital signal output element, which is provided at least for receiving and / or transmitting the digital signal, and an analog signal output element, which is provided for transmitting and / or receiving, in particular for reading out, the analog signal. Preferably, the electrical consumer and / or the charging device has at least one further signal output unit, which is provided for receiving and / or transmitting the analog and / or digital signal.

[0011] The analog signal output element preferably has at least one coding resistor, in particular for battery coding, and / or at least one NTC resistor, in particular as a temperature sensor for measuring a temperature of the battery pack, which can be read via the signal contact, in particular by the signal output unit of the electrical consumer and / or charger, preferably using the control and / or regulating unit of the electrical consumer and / or charger. The analog signal is preferably a signal provided by reading the resistor. In particular, the analog signal is used to read out a performance capacity, a voltage, a configuration and / or temperature of the battery pack, in particular of the battery cell. In particular, the analog signal output element has at least a resistance between 1 kOhm and 1 MOhm as a coding resistor, in particular adapted to the values ​​of the battery cell.In particular, the analog signal output element has an NTC resistor, in particular adapted to the values ​​of the battery cell, preferably temperature-dependent, in particular a resistance between 1 MOhm and 10 Ohm, preferably between 100 kOhm and 100 Ohm, and particularly preferably between 50 kOhm and 1 kOhm.

[0012] The battery pack preferably has at least one control and / or regulating unit, which is connected, in particular electrically, to the signal output unit at least for transmitting and / or receiving. The control and / or regulating unit is preferably provided for communication with the control and / or regulating unit of the electrical consumer and / or charger. In particular, the control and / or regulating unit at least partially forms the digital signal output element.

[0013] In particular, the digital signal output element for transmitting, in particular sending and / or receiving, the digital signal is at least partially designed as a digital bus system. Various protocols and driver circuits for such digital bus systems are known, including, but not limited to, UART and LIN. Preferably, the digital signal output element, in particular the digital bus system, operates according to a master / slave principle. In particular, the digital signal output element has a transmission element, in particular a bus line, for transmitting the digital signal. Preferably, the digital signal output element has a receiver circuit, in particular a receiver, and a pull-down circuit for receiving and / or transmitting the digital signal. Particularly preferably, the bus line is connected directly to the signal contact, wherein the analog signal and the digital signal can each be transmitted via the bus line.Preferably, the electrical consumer and / or the charger has, as a digital signal output element, the complementary digital bus system with at least one further transmission element, in particular a bus line, a receiver circuit and a pull-down circuit.

[0014] Preferably, the signal output unit, in particular circuit components for transmitting, preferably outputting, the digital signal, preferably at least the digital signal output element, particularly preferably at least the digital bus system of the signal output unit is connected to the signal contact, in particular builds on or supplements the signal contact. In at least one embodiment of the battery pack according to the invention, the signal output unit, preferably the digital signal output element, particularly preferably the digital bus system, is designed to be at least partially separable from the signal contact, in particular the battery pack. This advantageously makes it possible to supplement a battery pack which only has a signal output unit for analog signal transmission with the digital signal output element, particularly preferably the digital bus system.The digital signal is preferably a charge status, a cell voltage, a temperature measurement and / or temperature warning, an error message, an authentication signal, a remaining running time, or another signal deemed appropriate by a person skilled in the art. The digital signal advantageously serves to improve interaction between the electrical load, in particular the power tool, and the user, offers safety features, and contributes to extending the service life of the battery pack. In particular, the digital bus system is designed for a data rate of at least 1 kbaud, preferably at least 10 kbaud, advantageously at least 50 kbaud, and particularly preferably at least 100 kbaud. In particular, slower data rates may also be appropriate depending on the application.

[0015] Preferably, the electrical circuit is configured to switch at least one electrical circuit component when switching between the analog operating mode and the digital operating mode such that the signal output unit outputs only the analog signal or the digital signal, in particular via at least the same signal contact of the connection interface. Preferably, the signal output unit is configured to output the analog signal in the analog operating mode. Particularly preferably, the electrical circuit is configured to provide a readout of the analog signal output element, in particular the coding resistor or the NTC resistor, in the analog operating mode. Preferably, the signal output unit is configured to output the digital signal in the digital operating mode.Particularly preferably, the electrical circuit in the digital operating mode is configured to provide for the transmission and / or reception of the digital signal, preferably during communication between the control and / or regulating unit of the battery pack and the control and / or regulating unit of the electrical consumer and / or the charger. In particular, the electrical circuit at least partially forms the digital bus system.

[0016] It is further proposed that the electrical circuit be configured to electrically separate the analog signal output element of the signal output unit from the signal contact in the digital operating mode of the signal output unit. This advantageously makes it possible to achieve a signal level required for bus communication as easily and stably as possible, despite a range of resistances determined by the analog signal output element. Preferably, the electrical circuit detects when digital communication is to take place, so that the electrical circuit electrically separates the analog signal output element from the signal contact. Particularly preferably, the digital signal output element, in particular the digital bus system, is unaffected by the analog signal output element in the digital operating mode of the signal output unit.The digital signal output element, in particular the digital bus system, preferably has an ESD protection circuit, which is preferably configured, particularly in the digital operating mode, preferably together with the analog signal output element, to reduce the existing capacitance, in particular to a maximum of 100 nF, preferably to a maximum of 10 nF, advantageously to a maximum of 5 nF, and particularly preferably to a maximum of 1 nF. This advantageously allows the switching edges of the bus line to be transmitted immediately. The ESD protection circuit preferably has at least one ESD suppressor diode.

[0017] It is further proposed that the electrical circuit be configured to electrically separate the digital signal output element of the signal output unit from the signal contact in an analog operating mode of the signal output unit. This advantageously enables the output of the analog signal, in particular a readout of the analog signal output element, preferably when the digital signal output element is implemented on the same signal contact. Preferably, the electrical circuit detects when a digital signal output has ended, so that the electrical circuit electrically separates the digital signal output element from the signal contact. Particularly preferably, the analog signal output element is unaffected by the digital signal output element in the analog operating mode of the signal output unit.Preferably, the electrical circuit is configured to prevent a current flowing parallel to the analog signal output element in the analog operating mode. Particularly preferably, the electrical signal output unit is electrically isolated from the signal contact outside of a digital signal transmission in the analog operating state, and in particular, the digital signal output element is electrically isolated from the signal contact.

[0018] It is also proposed that the electrical circuit comprise at least a first switching element for the electrical isolation of the digital signal output element and at least one further switching element for the electrical isolation of the analog signal output element. This advantageously makes it possible to provide switching between the digital operating mode and the electrical operating mode using cost-effective and widely available components. Preferably, the first switching element for the electrical isolation of the digital signal output element and the at least one further switching element for the isolation of the analog signal output element are designed separately from one another. Preferably, the first switching element is configured to prevent current flowing parallel to the analog signal output element in the analog operating mode. Particularly preferably, the first switching element is a semiconductor switch, such as an npn BJT and / or n-type MOSFET.Particularly preferably, the first switching element is arranged in the digital signal output element, in particular in the digital bus system, preferably in an input circuit of the receiver circuit of the digital signal output element. The input circuit is preferably part of the electrical circuit. In particular, the at least one further switching element is arranged directly on the analog signal output element. Preferably, the further switching element is designed as a semiconductor switch, in particular as a MOSFET semiconductor switch. When using an NTC resistor as the analog signal output element, the MOSFET semiconductor switch, which is already established for an NTC resistor, is preferably designed as the further switching element.

[0019] Furthermore, it is proposed that the switching element, in particular the first one, is configured to electrically separate the discharge paths of the digital signal output element from the ground of the battery pack in the analog operating mode of the signal output unit. This advantageously provides a trouble-free analog operating mode, in particular trouble-free readout of the analog signal output element. Preferably, the switching element, in particular the first one, is configured in the analog operating mode to prevent the current flowing parallel to the analog signal output element via the discharge paths to ground. In particular, the switching element is provided to prevent a current flow through the digital bus system. Preferably, a current flow through the analog signal output element is provided in the analog operating mode.

[0020] It is further proposed that the signal output unit have at least one activation unit which is configured to switch from the analog operating mode to the digital operating mode upon detection and / or recognition of an activation signal, in particular a digital one. This advantageously prevents interference with the analog signal output element, in particular in the analog operating mode. Preferably, the switching element, in particular the first switching element, is configured to close the discharge paths of the digital signal output element to ground, in particular based on the activation signal. Particularly preferably, the activation unit is provided for pulse detection. Particularly preferably, the activation signal is a pulse sequence which preferably has signal edges within a defined time period.The activation signal is preferably binary, although any defined binary coding is conceivable, such as "101 0101." The activation unit is preferably configured to at least substantially prevent interference signals from the digital signal output element in the analog operating mode. Particularly preferably, the activation unit comprises at least one high-pass filter, which is at least configured to permanently prevent a current flow in the activation unit, in particular in the analog operating mode. The activation unit preferably comprises at least one transistor, in particular an npn BJT transistor. The high-pass filter is preferably provided to pass a filtered signal, preferably the activation signal, to the transistor.Preferably, the transistor is provided to transmit the signal, preferably the activation signal, to the control and / or regulating unit, which is preferably provided to verify the signal, preferably the activation signal. In particular, the control and / or regulating unit is provided to establish the digital operating mode upon verification of the signal as an activation signal, wherein, in particular, the control and / or regulating unit closes the first switching element to electrically isolate the digital signal output element and opens the further switching element to electrically isolate the analog signal output element.

[0021] Particularly preferably, the activation unit comprises at least one diode configured to decouple a capacitance of the high-pass filter from the transmission element, in particular the bus line. This advantageously reduces interference with the bus line, particularly in the digital operating mode. In particular, the diode is designed as a Schottky diode, preferably due to a lower forward voltage. Preferably, the activation unit comprises a resistor, which is preferably connected in parallel with the high-pass capacitor. In particular, the resistor is provided to ensure a defined discharge of the capacitor.

[0022] In an alternative embodiment of the battery pack according to the invention, the activation unit has an activation switch on a battery pack housing and / or on the electrical consumer and / or charger. In particular, the activation switch is manually operable. The activation switch is preferably designed to switch the signal output unit from the analog operating mode to the digital operating mode.

[0023] It is also proposed that the battery pack comprise at least the energy storage device, which is configured at least to provide usable energy for operating the electrical consumer and a signal voltage of the signal output unit for the digital operating mode. The voltage level of the signal voltage preferably reaches sufficiently high values ​​of preferably at least 5 V, particularly preferably up to the battery voltage itself. This advantageously makes it possible to provide a large voltage swing relative to ground, which advantageously enables steep signal edges. Furthermore, the steep signal edges can advantageously be provided even with large series resistors upstream of the energy storage device. The signal output unit preferably comprises at least one series resistor upstream of the energy storage device, in particular to the digital signal output element.Preferably, the digital signal output element, in particular the digital bus system, is connected to the energy storage device, preferably from the bus master, via a series resistor. Particularly preferably, the series resistor is arranged in the corresponding signal output unit of the electrical consumer and / or charger. The series resistor preferably has a resistance of, in particular, at least 100 ohms, preferably at least 500 ohms, advantageously 1 kOhm, and particularly preferably at least 2 kOhms. In particular, for example, in an energy storage device with 5 Li-ion cells, the signal voltage, in particular as a pull-up voltage, is between 15 V and 21 V.

[0024] It is further proposed that the signal output unit have at least one voltage regulation unit which is configured to stabilize and / or regulate the signal voltage, in particular to regulate it down to a constant value which is lower than an output voltage of the energy storage device. This advantageously makes it possible to achieve a stable voltage across the entire battery voltage range. Furthermore, interference emission can advantageously be improved by limiting maximum voltage swings. Furthermore, a receiver can advantageously be recognized in the digital bus system with a transmitter using the defined voltage level in an optimized manner. The voltage regulation unit preferably has at least one diode, in particular a Zener diode, for example an 8 V Zener diode.In particular, the voltage regulation unit has a series resistor which preferably has a resistance between 50 ohms and 10 kOhms, advantageously between 100 ohms and 1 kOhms, and particularly preferably between 250 ohms and 500 ohms. A series resistor with 330 ohms is particularly suitable. In particular, the voltage regulation unit regulates the output voltage by at least 10%, preferably by at least 25%, advantageously by at least 33%, and particularly preferably by at least 45%. The signal voltage, in particular as a high level, is preferably kept by the voltage regulation unit at a constant value between 30 V and 1 V, preferably between 20 V and 2 V, advantageously between 15 V and 5 V, and particularly preferably between 10 V and 6 V. In particular, with an 8 V Zener diode, the signal voltage is approximately 8 V.In particular, the receiver circuit is configured to convert the signal voltage into a value that can be processed by the control and / or regulating unit, in particular a logic 1, for example by converting it to 3.3 V. Preferably, the conversion of the receiver circuit is provided by a semiconductor switch, for example, an n-type MOSFET semiconductor switch and / or an npn BJT semiconductor switch.

[0025] It is further proposed that the signal output unit comprise at least one voltage divider configured to compensate for a ground offset between the battery pack and the electrical load and / or the charger, in particular between the ground of the battery pack and a ground of the electrical load and / or charger. This advantageously provides stable signal transmission, in particular a clear low level, despite a high ground offset, in particular a ground offset of up to 2 V, between the battery pack and the electrical load and / or the charger, in particular between master and slave. Particularly preferably, the voltage divider is connected in the input circuit of the receiver circuit of the digital signal output element. Preferably, the voltage divider is connected upstream of the semiconductor switch for conversion, in particular the n-type MOSFET semiconductor switch and / or the npn BJT semiconductor switch.In particular, the voltage divider has a series resistor and a bleeder resistor. The voltage divider preferably has a voltage divider ratio, in particular between 5% and 50%, preferably between 8% and 30%, advantageously between 10% and 20%, and particularly preferably between 10% and 15%. Particularly preferably, the voltage divider has a voltage divider ratio of approximately 13%, with the series resistor being approximately 10 kOhm and the bleeder resistor being approximately 1.5 kOhm.

[0026] The invention further relates to a system with the battery pack and with an electrical consumer and / or with a charger, each comprising at least the connection interface to the connection with the battery pack and at least the signal output unit, which is configured to at least output the analog signal via the connection interface at least via the signal contact of the battery pack.

[0027] The inventive design of the system enables fast data transmission on a sensitive interface, which is advantageously robust against electrostatic discharges and / or has high electromagnetic compatibility. Furthermore, a system with an electrical load and / or a charger can advantageously be provided, which is designed for both digital data exchange and analog data exchange, in particular via the one connection interface.

[0028] The invention also relates to a method for operating the battery pack, wherein switching takes place between the analogue operating mode and the digital operating mode in at least one method step.

[0029] The method according to the invention advantageously enables fast data transmission on a sensitive interface that is advantageously robust against electrostatic discharges and / or has high electromagnetic compatibility. This advantageously ensures the safest and most efficient operation of the battery pack's energy storage device.

[0030] Preferably, after the activation signal has been detected, the activation unit switches from the analog operating mode to the digital operating mode. Preferably, when switching from the analog operating mode to the digital operating mode, at least the first switching element for electrically isolating the digital signal output element is closed and, in particular, the at least one further switching element for electrically isolating the analog signal output element is opened. Preferably, when switching from the digital operating mode to the analog operating mode, at least the first switching element for electrically isolating the digital signal output element is opened and, in particular, the at least one further switching element for electrically isolating the analog signal output element is closed.

[0031] The battery pack according to the invention, the system according to the invention, and / or the method according to the invention are not intended to be limited to the application and embodiment described above. In particular, the battery pack according to the invention, the system according to the invention, and / or the method according to the invention may, in order to fulfill a functionality described herein, have a number of individual elements, components, units, and method steps that differs from the number stated herein. Furthermore, in the value ranges specified in this disclosure, values ​​within the stated limits are also to be considered disclosed and can be used arbitrarily. drawing

[0032] Further advantages will become apparent from the following description of the drawings. The drawings illustrate two exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0033] They show: Fig. 1 a system according to the invention with a battery pack and with an electrical consumer, in particular an electric hand tool, Fig. 2 a conceptual diagram of a signal output unit of the battery pack and a signal output unit of the electrical load, Fig. 3 a circuit of an input circuit of a receiver circuit of the signal output unit of the battery pack, Fig. 4 a circuit of an activation unit of the signal output unit of the battery pack, Fig. 5 a method for operating the battery pack and Fig. 6 a conceptual representation of an alternative embodiment of a signal output unit of a battery pack according to the invention. Description of the embodiments

[0034] The Fig. Figure 1 schematically shows a system 12a with a battery pack 10a and an electrical load 14a. The electrical load 14a is designed as an electric hand tool 16a, in particular as a battery-operated hammer drill. Alternatively, however, it is also conceivable for the load 14a to be designed as another load 14a that would be deemed appropriate by a person skilled in the art. The battery pack 10a is detachably attached to the load 14a, in particular in a non-destructive manner.

[0035] The battery pack 10a comprises an energy storage device 70a. The energy storage device 70a is configured to at least provide usable energy for operating the electrical consumer 14a. The energy storage device 70a comprises a plurality of battery cells that are connected in series with one another. Alternatively, it is also conceivable for the energy storage device 70a to have only one battery cell. The battery pack 10a is designed as a lithium-ion battery pack 10a. Alternatively, it is also conceivable for the battery pack 10a to be designed as a nickel-cadmium battery pack 10a or as another battery pack 10a that a person skilled in the art would deem appropriate. The energy storage device 70a has, for example, five Li-ion cells. The energy storage device 70a thus provides a pull-up voltage between 15 V and 21 V.

[0036] The battery pack 10a comprises at least one control and / or regulating unit 24a. The control and / or regulating unit 24a comprises at least one processor and one memory element, as well as an operating program stored on the memory element. The memory element is designed as a digital storage medium, for example, as a hard disk or the like. The control and / or regulating unit 24a has at least one protective function for protecting the battery cells. The protective function is dependent, for example, on the at least one operating parameter. The operating parameter can be a voltage parameter, a current parameter, a resistance parameter, a temperature parameter, or the like. The control and / or regulating unit 24a is preferably deactivated when the battery pack 10a is inactive. The control and / or regulating unit 24a is particularly preferably deactivated when the battery pack 10a is inactive, in particular in order to achieve the lowest possible power consumption.

[0037] The battery pack 10a has at least one connection interface 20a. The connection interface 20a is provided for connection to the electrical load 14a. The electrical load 14a has a further connection interface 22a. The further connection interface 22a of the electrical load 14a is provided for connection to the battery pack 10a, in particular the connection interface 20a of the battery pack 10a.

[0038] The battery pack 10a is designed to supply the electrical load 14a with electrical energy via the connection interface 20a. The connection interface 20a serves as an electromechanical interface between the electrical load 14a and / or the charger. The connection interface 20a has at least two power contacts configured for an electrical connection to the electrical load 14a, in particular to two power contacts of the connection interface 22a of the electrical load 14a. The connection interface 20a of the battery pack 10a consists of contact tulips, which are inserted into one another as contact blades to form a connection to the connection interface 22a of the electrical load 14a.

[0039] The connection interface 20a has at least one signal contact 34a (see Fig. 2). The signal contact 34a is provided for signal transmission from the battery pack 10a to the electrical load 14a. The signal contact 34a is formed in the connection interface 20a separately from the power contacts. The signal contact 34a is provided for transmitting an analog signal from the battery pack 10a to the electrical load 14a. The signal contact 34a is provided for transmitting a digital signal from the battery pack 10a to the electrical load 14a. The connection interface 22a of the electrical load 14a has a further signal contact 34a. The further signal contact 34a of the connection interface 22a of the electrical load 14a is provided for transmitting a digital signal from the electrical load 14a to the battery pack 10a.The signal contact 34a of the connection interface 20a of the battery pack 10a is in electrical, in particular electromechanical, contact with the further signal contact 34a of the connection interface 22a of the electrical load 14a. The analog signal is transmitted from the signal contact 34a of the connection interface 20a of the battery pack 10a via the further signal contact 34a of the connection interface 22a of the electrical load 14a. The digital signal is transmitted from the signal contact 34a of the connection interface 20a of the battery pack 10a via the further signal contact 34a of the connection interface 22a of the electrical load 14a.

[0040] The battery pack 10a has at least one signal output unit 30a. The signal output unit 30a is configured to output at least one analog signal and at least one digital signal via at least one same signal contact 34a of the connection interface 20a (see also Fig. 2). The signal output unit 30a at least partially forms the signal contact 34a or is at least partially modulated onto the signal contact 34a. The electrical load 14a has a further signal output unit 32a. The signal output unit 32a of the electrical load 14a is configured to at least output the analog signal at least via the signal contact 34a of the battery pack 10a. The signal output unit 32a of the electrical load 14a is configured to at least output the digital signal at least via the same signal contact 34a of the battery pack 10a.

[0041] The control and / or regulating unit 24a is connected to the signal output unit 30a at least for transmitting and / or receiving the digital signal. The control and / or regulating unit 24a is provided for communication with another control and / or regulating unit 26a of the electrical load 14a, in particular via the signal output unit 30a of the battery pack 10a and the another signal output unit 32a of the electrical load 14a.

[0042] The digital signal is a charge status, a cell voltage, a temperature measurement and / or temperature warning, an error message, an authentication signal, a remaining runtime, or any other signal deemed appropriate by a professional. The digital signal serves to improve the interaction between the electrical load 14a, in particular the power tool 16a, and the user, provides safety features, and contributes to extending the service life of the battery pack 10a.

[0043] The analog signal is provided by at least one coding resistor, in particular for battery coding. Alternatively and / or additionally, the analog signal is provided by at least one NTC resistor, in particular as a temperature sensor for measuring a temperature of the battery pack 10a, which can be read via the signal contact 34a, in particular by the signal output unit 32a of the electrical consumer 14a, preferably by means of the control and / or regulating unit 26a of the electrical consumer 14a. The analog signal is a signal provided by reading a coding resistor or NTC resistor. The analog signal serves to read out a performance, a voltage, a configuration and / or temperature of the battery pack 10a, in particular of the battery cell (see also Fig. 2).

[0044] The battery pack 10a is intended for connection to at least one charger. The charger has at least one connection interface. The charger has at least one signal transmission unit. The charger has an input connection connected to an external energy source and an output connection connected to the battery pack 10a. Within the charger is a control and / or regulating unit that monitors and controls the charging processes. In the further description of the exemplary embodiment, only the connection to the electrical load 14a is described in more detail. However, the description of the electrical load 14a is equally applicable to the charger. The charger has at least approximately the same components as the electrical load 14a. The charger can be used analogously for each described feature of the electrical load 14a.The only difference could be in the power supply of the signal transmission unit, whereby it is conceivable that the charger is supplied with power via an external power supply.

[0045] The Fig. 2 conceptually shows the signal output unit 30a of the battery pack 10a and the signal output unit 32a of the electrical load 14a.

[0046] The signal output unit 30a has an analog signal output element 40a. The analog signal output element 40a is provided for outputting the analog signal. The analog signal is a signal generated by reading the analog signal output element 40a. The analog signal output element 40a is the coding resistor, in particular for battery coding, and / or at least the NTC resistor, in particular as a temperature sensor for measuring a temperature of the battery pack 10a. The resistance of the coding resistor is, for example, between 1 kOhm and 1 MOhm. The coding resistor depends on the values ​​of the energy storage device 70a. The resistance of the NTC resistor is, for example, between 50 kOhm and 1 kOhm, depending on the temperature. The NTC resistor depends on the values ​​of the energy storage device 70a.

[0047] The signal output unit 30a has at least one digital signal output element 36a. The digital signal output element 36a is provided for outputting the digital signal. The digital signal output element 36a is provided for receiving and / or transmitting the digital signal. The digital signal output element 36a at least partially forms a digital bus system 28a. Various protocols and driver circuits are applicable for the digital bus system 28a, including, but not limited to, UART and LIN. The digital signal output element 36a has a transmission element 100a for transmitting the digital signal. The transmission element 100a forms a bus line 104a. The digital signal output element 36a has a receiver circuit 90a, in particular a receiver, for receiving and / or transmitting the digital signal. The digital signal output element 36a has a pull-down circuit 108a for receiving and / or transmitting the digital signal.The signal output unit 30a is connected to a ground 50a.

[0048] The digital signal output element 36a has an ESD protection circuit 96a. The ESD protection circuit 94a has at least one ESD suppressor diode (not shown). The ESD protection circuit 94a is configured to reduce existing capacitance in the digital operating mode, preferably together with the analog signal output element 40a. The ESD protection circuit 94a is configured to reduce the capacitance to a maximum of 100 nF, preferably to a maximum of 10 nF, advantageously to a maximum of 5 nF, and particularly preferably to a maximum of 1 nF. This advantageously allows the switching edges of the bus line 104a to be transmitted immediately.

[0049] The bus line 104a is directly connected to the signal contact 34a. The analog signal and the digital signal can each be transmitted via the bus line 104a. The electrical load 14a has, as a digital signal output element 38a, the complementary digital bus system 28a with at least one further transmission element 102a, in particular a bus line 106a, a receiver circuit 92a, a pull-down circuit 110a, and an ESD protection circuit 98a. The signal output unit 32a of the electrical load 14a is connected to a further ground 52a. The digital signal output element 36a of the battery pack 10a and the digital signal output element 38a form the digital bus system 28a.

[0050] The signal output unit 32a, in particular an electrical circuit 44a of the signal output unit 32a, of the electrical load 14a has at least one series resistor 62a. The digital bus system 28a, in particular the signal output unit 32a of the electrical load 14a and the signal output unit 30a of the battery pack 10a, is connected to the energy storage device 70a via the series resistor 62a. The series resistor 62a has a resistance of in particular at least 100 ohms, preferably at least 500 ohms, advantageously 1 kOhm, and particularly preferably at least 2 kOhm. The energy storage device 70a is configured to provide a signal voltage to the signal output unit 30a for the digital operating mode.

[0051] The digital bus system 28a operates according to a master / slave principle. The master serves as the primary driver, providing a constant pull-up voltage, e.g., 3.3V or 5V. The master switches the digital bus system 28a to 0V (pull-down) to transmit the digital signal. The digital bus system 28a is designed for a data rate of at least 1 kbaud, preferably at least 10 kbaud, advantageously at least 50 kbaud, and particularly preferably at least 100 kbaud. Depending on the application, slower data rates may also be appropriate.

[0052] The signal output unit 30a has at least one electrical circuit 42a. The electrical circuit 42a is configured to switch between a digital operating mode and an analog operating mode. The electrical circuit 42a comprises at least circuit components of the battery pack 10a of the digital bus system 28a. The signal output unit 32a of the electrical load 14a has a further electrical circuit 42a, which comprises the circuit components of the electrical load 14a of the digital bus system 28a. In the analog operating mode, the signal output unit 30a is configured to output the analog signal. In the digital operating mode, the signal output unit 30a is configured to output the digital signal.The electrical circuit 42a is configured to switch at least one electrical circuit component when switching between the analog operating mode and the digital operating mode such that the signal output unit 30a outputs only the analog signal or the digital signal, in particular via at least the same signal contact 34a of the connection interface 20a. The electrical circuit 42a at least partially forms the digital bus system 28a. The electrical circuit 42a is connected to the electrical circuit 44a of the electrical load 14a.

[0053] In the analog operating mode, the electrical circuit 42a is configured to provide a readout of the analog signal output element 40a, in particular the coding resistor or the NTC resistor. In the digital operating mode, the electrical circuit 42a is configured to provide the transmission and / or reception of the digital signal, preferably during communication between the control and / or regulating unit 24a of the battery pack 10a and the control and / or regulating unit 26a of the electrical load 14a.

[0054] The electrical circuit 42a is configured to electrically isolate the analog signal output element 40a of the signal output unit 30a from the signal contact 34a in the digital operating mode of the signal output unit 30a. The electrical circuit 42a comprises at least one switching element 48a for electrically isolating the analog signal output element 40a. The switching element 48a is arranged directly on the analog signal output element 40a. The switching element 48a is designed as a semiconductor switch, in particular as a MOSFET semiconductor switch. When an NTC resistor is used as the analog signal output element 40a, the MOSFET semiconductor switch already established in an NTC resistor is designed as the switching element 48a. In the analog operating mode, the switching element 48a is closed. In the digital operating mode, the switching element 48a is open.The electrical circuit 42a is configured to electrically separate the digital signal output element 36a of the signal output unit 30a from the signal contact 34a in the analog operating mode of the signal output unit 30a (cf. . Fig. 3).

[0055] The Fig. Figure 3 shows an input circuit 112a of the receiver circuit 90a of the signal output unit 30a of the battery pack 10a. The input circuit 112a is part of the electrical circuit 42a of the signal output unit 30a.

[0056] The electrical circuit 42a comprises at least one switching element 46a for electrically isolating the digital signal output element 36a. The switching element 46a for electrically isolating the digital signal output element 36a and the at least one further switching element 48a for isolating the analog signal output element 40a are formed separately from one another. The switching element 46a is configured to prevent the current flowing parallel to the analog signal output element 40a in the analog operating mode. The switching element 46a is a semiconductor switch. The switching element 46a is an n-type MOSFET semiconductor switch. Alternatively, an npn BJT can also be used as a semiconductor switch. The first switching element 46a is arranged in the digital signal output element 36a, in particular in the digital bus system 28a, preferably in the input circuit 112a of the receiver circuit 90a of the digital signal output element 36a.The switching element 46a is configured to electrically isolate the discharge paths of the digital signal output element 36a from a ground 50a of the battery pack 10a in the analog operating mode of the signal output unit 30a. The switching element 46a is configured to prevent the current flowing parallel to the analog signal output element 40a via the discharge paths to ground 50a in the analog operating mode.

[0057] The signal output unit 30a has at least one voltage divider 80a. The voltage divider 80a is configured to compensate for a ground offset between the battery pack 10a and the electrical load 14a. The voltage divider 80a is configured to compensate for a ground offset between the ground 50a of the battery pack 10a and the ground 52a of the electrical load 14a, in particular of up to 2 V. In the input line 112a of the receiver circuit 90a, the voltage divider 80a is connected upstream of a semiconductor switch 86a. The voltage divider 80a has a series resistor 82a and a bleeder resistor 84a. By implementing a series resistor 82a of, for example, 10 kOhm and a bleeder resistor 84a of 1.5 kOhm, a voltage divider ratio of approximately 13% is achieved. This results in a ground offset influenced “low” level of 2 V being reduced to about 260 mV.This value is significantly below the switching threshold of semiconductor switch 86a. Despite the voltage divider 80a, a "high" level still reaches a value of more than 1 V due to the signal voltage of energy storage device 70a, which is above the switching threshold of the semiconductor switch. Depending on the specific requirements of system 12a, fine adjustment can be made by varying the "high" level on bus line 104, the switching thresholds of semiconductor switch 86a, and the expected ground offsets. Semiconductor switch 86a is an npn BJT semiconductor switch with a switching waveform of approximately 0.7 V.

[0058] The Fig. 4 shows a circuit of an activation unit 60a of the signal output unit 30a of the battery pack 10a. The activation unit 60a is configured to switch from the analog operating mode to the digital operating mode upon detection and / or recognition of an activation signal. The activation signal is a digital signal. The activation unit 60a is configured to switch the at least one first switching element 46a and the at least one further switching element 48a upon detection of the activation signal.

[0059] The activation unit 60a is provided for detecting pulses on the bus line 104. The activation signal is a defined pulse sequence having signal edges within a defined time period. The activation signal is binary, whereby any defined binary coding is conceivable, such as "101 0101." The activation unit 60a is configured to at least substantially prevent interference signals from the digital signal output element 36a in the analog operating mode. The control and / or regulating unit 24a of the battery pack 10a or the control and / or regulating unit 26a of the electrical load 14a is provided for generating the activation signal.

[0060] The activation unit 60a has at least one high-pass filter 62a. The high-pass filter 62a is configured to permanently prevent a current flow in the activation unit 60a, particularly in the analog operating mode. The activation unit 60a has at least one transistor 68a, particularly an npn BJT transistor. The high-pass filter 62a is provided to pass the pulse sequence, preferably the activation signal, in a filtered form to the transistor 62a. The transistor 62a is provided to transmit the pulse sequence, preferably the activation signal, to the control and / or regulating unit 24a. The control and / or regulating unit 24a is provided to check the pulse sequence, preferably of the activation signal.The control and / or regulating unit 24a is provided to set the digital operating mode upon verification of the pulse sequence as an activation signal, wherein in particular the control and / or regulating unit 24a closes the first switching element 46a for the electrical isolation of the digital signal output element 36a and opens the further switching element 48a for the electrical isolation of the analog signal output element 40a.

[0061] The activation unit 60a has at least one diode 66a, which is configured to decouple a capacitance of the high-pass filter 62a from the transmission element 100a, in particular the bus line 102a. The diode 66a is designed as a Schottky diode due to a lower forward voltage. The activation unit 60a has a resistor 64a connected in parallel with a high-pass capacitor. The resistor 64a is provided to ensure a defined discharge of the capacitor. The resistor 64a has a value of 1 MOhm, for example.

[0062] The Fig. 5 shows a method 150a for operating the battery pack 10a. In at least one method step, switching occurs between the analog operating mode and the digital operating mode.

[0063] In a method step 152a, the signal output unit 30a is operated in the analog operating mode. The signal output unit 30a outputs the analog signal via the signal contact 34a.

[0064] In a further method step 154a for initiating a switch to the digital operating mode, the activation signal is generated by the control and / or regulating unit 24a of the battery pack 10a or the control and / or regulating unit 26a of the electrical load 14a. The activation signal is transmitted on the bus line 104a.

[0065] In a further method step 156a, the activation unit 60a detects the pulse. If a positive pulse occurs on the bus line 104a, it is filtered by the high-pass filter 62a and passed to the base of the transistor 68a. The transistor 68a is temporarily turned on and passes the pulse sequence to the control and / or regulating unit 24a.

[0066] In a further method step 158a, after the activation signal has been detected, the activation unit 60a switches from the analog operating mode to the digital operating mode. If the activation signal is detected from the pulse sequence by the control and / or regulating unit 24a, the first switching element 46a and the at least one further switching element 48a are switched by the control and / or regulating unit 24a. During the switch from the analog operating mode to the digital operating mode, at least the first switching element 46a is closed to electrically isolate the digital signal output element 36a, and the at least one further switching element 48a is opened to electrically isolate the analog signal output element 40a.

[0067] In a further method step 160a, the signal output unit 30a is operated in the digital operating mode. The signal output unit 30a is provided for outputting the digital signal via the signal contact 34a.

[0068] If no digital signal is output or received via the signal output unit 30a, the digital operating mode switches to the analog operating mode. In a further method step 162a, at least the first switching element 46a is opened to electrically isolate the digital signal output element 36a, and in particular, the at least one further switching element 48a is closed to electrically isolate the analog signal output element 40a. The discharge paths of the digital signal output element 36a are opened to ground 50a.

[0069] In the Fig. 6 shows a further embodiment of the invention. The following descriptions and the drawings are essentially limited to the differences between the embodiments, whereby with regard to components with the same designation, in particular with regard to components with the same reference numerals, reference is also made to the drawings and / or the description of the other embodiments, in particular to the Fig. 1 to 5. To distinguish the embodiments, the letter a is added to the reference numerals of the embodiment in the Fig. 1 to 5. In the example of the Fig. 6, the letter a is replaced by the letter b.

[0070] The Fig.6 conceptually shows an alternative embodiment of a signal output unit 30b of a battery pack 10b according to the invention. The signal output unit 30b is provided for outputting a digital signal or an analog signal via a signal contact 34b to an electrical load 14b, in particular a signal output unit 32b of the electrical load 14b.

[0071] The signal output unit 30b has at least one voltage regulation unit 120b. The voltage regulation unit 120b is configured to stabilize and / or regulate a signal voltage. The voltage regulation unit 120b is configured to regulate the signal voltage to a constant value, which is significantly lower than an output voltage of an energy storage device 70b of the battery pack 10b.

[0072] The voltage regulation unit 120b has at least one diode, in particular a Zener diode, for example an 8 V Zener diode (not shown). The voltage regulation unit 120b has a series resistor (not shown). A series resistor of 330 ohms is particularly suitable. The voltage regulation unit 120b regulates the output voltage by at least 10%, preferably by at least 25%, advantageously by at least 33%, and particularly preferably by at least 45%. The voltage regulation unit 120b regulates the signal voltage constantly to 8 V. A receiver circuit 90b of the signal output unit 30b is configured to convert the signal voltage into a value that can be processed by a control and / or regulating unit 24b of the battery pack 10b, in particular a "logic 1", for example by converting to 3.3 V. The receiver circuit 90b has a semiconductor switch 86b for the conversion.

[0073] The signal output unit 32b of the electrical load 14b has a switch 122b. The switch 122b is configured to disconnect an energy storage device 70b of the battery pack 10b from at least the signal output unit 32b of the electrical load 14b and the signal output unit 30b of the battery pack 10b.

Claims

[1] Battery pack (10a; 10b) with at least one connection interface (20a; 20b) for connection to an electrical consumer (14a; 14b), in particular an electric hand tool (16a; 16b), and / or to a charger, with a signal output unit (30a; 30b) which is designed to output at least one analogue signal and at least one digital signal via at least one same signal contact (34a; 34b) of the connection interface (20a; 20b), characterized by that the signal output unit (30a; 30b) has at least one electrical circuit (42a; 42b) which is designed to switch between a digital operating mode of the signal output unit (30a; 30b) and an analog operating mode of the signal output unit (30a; 30b). [2] Battery pack (10a; 10b) according to claim 1, characterized bythat the electrical circuit (42a; 42b) is configured to electrically separate the analog signal output element (40a; 40b) of the signal output unit (30a; 30b) from the signal contact (34a; 34b) in the digital operating mode of the signal output unit (30a; 30b). [3] Battery pack (10a; 10b) according to one of the preceding claims, characterized by that the electrical circuit (42a; 42b) is configured to electrically separate the digital signal output element (36a; 36b) of the signal output unit (30a; 30b) from the signal contact (34a; 34b) in the analogue operating mode of the signal output unit (30a; 30b). [4] Battery pack (10a; 10b) according to one of the preceding claims 2 or 3, characterized bythat the electrical circuit (42a; 42b) comprises at least one first switching element (46a; 46b) for the electrical isolation of the digital signal output element (36a; 36b) and at least one further switching element (48a; 48b) for the electrical isolation of the analog signal output element (40a; 40b). [5] Battery pack (10a; 10b) according to claim 4, characterized by in that the switching element (46a; 46b) is configured to electrically separate discharge paths of the digital signal output element (36a; 36b) from a ground (50a; 50b) of the battery pack (10a; 10b) in the analogue operating mode of the signal output unit (30a; 30b). [6] Battery pack (10a; 10b) according to one of the preceding claims, characterized bythat the signal output unit (30a; 30b) has at least one activation unit (60a; 60b) which is designed to switch from the analogue operating mode to the digital operating mode upon detection and / or recognition of an activation signal, in particular a digital one, in particular to switch the at least one first switching element (46a; 46b) and the at least one further switching element (48a; 48b). [7] Battery pack (10a; 10b) according to one of the preceding claims, characterized by at least one energy store (70a; 70b) which is configured at least to provide useful energy for operating the electrical consumer (14a; 14b) and a signal voltage of the signal output unit (30a; 30b) for the digital operating mode. [8] Battery pack (10b) according to claim 7, characterized byin that the signal output unit (30b) has at least one voltage control unit (120b) which is designed to stabilize and / or regulate the signal voltage, in particular to regulate it down to a constant value which is lower than an output voltage of the energy store (70b). [9] Battery pack (10a; 10b) according to one of the preceding claims, characterized by that the signal output unit (30a; 30b) has at least one voltage divider (80a; 80b) which is designed to compensate for a ground offset between the battery pack (10a; 10b) and the electrical consumer (14a; 14b) and / or the charger. [10] System (12a; 12b) with a battery pack (10a; 10b) according to one of claims 1 to 9 and with an electrical consumer (14a; 14b) and / or with a charger, each having at least one connection interface (22a; 22b) for a connection to the battery pack (10a; 10b) and at least one signal output unit (30a; 30b) which is designed to at least output an analog signal via the connection interface (22a; 22b) at least via the signal contact (34a; 34b) of the battery pack (10a; 10b). [11] Method (150a; 150b) for operating a battery pack (10a; 10b) according to one of claims 1 to 9, wherein in at least one method step switching is carried out between an analogue operating mode and a digital operating mode.

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