WO2012123178A2 - Safety charging device - Google Patents

Abstract

A charging device for a chargeable electrical energy store comprises a current source having two current terminals for providing a charging current for charging the energy store, a first monitoring device and an assigned interruption device for interrupting the charging current in the case of a charging fault, and a second interruption device in the form of a fusible link for interrupting the charging current in the case where the charging current rises above a predetermined threshold value.

Description

 description

title

 Safety charging device The invention relates to a charging device for a rechargeable electric

Energy storage. Furthermore, the invention relates to an adapter for a charger for charging an energy store.

State of the art

Modern electrical energy storage devices, such as those used for operating small electrical appliances, include a number of battery cells for storing the electrical energy and control electronics for monitoring and controlling an energy exchange of the individual battery cells. Such an electronic control system is particularly suitable for lithium-ion batteries and nickel

Metal hydride batteries usual. When charging the energy storage to a charger, the control electronics, for example, ensures that the energy storage is not too fast and not too charged. As a result, an explosion or fire hazard when charging the energy storage can be minimized. Furthermore, modern energy storage devices include structural devices in the region of the individual battery cells in order to minimize the risk to a user or to an environment of the energy storage device.

In DE 102 03 909 a charging device for an electrical energy storage is shown, in which a redundant protection against a charging error in the energy storage is provided.

Due to the high prevalence of such energy storage devices and a potential hazard posed by such an energy storage device, it is desirable to further minimize a potential hazard during the charging of such an energy storage device. The invention solves this problem by a charging device with the features of claim 1 and by an adapter for a charger with the features of claim 8. Subclaims indicate preferred embodiments.

Disclosure of the invention

A charging device according to the invention for a rechargeable electrical energy store comprises a power source with two power terminals for providing a charging current for charging the energy storage device, a first monitoring device and an associated interruption device for interrupting the charging current in the event of a charging error and a second interrupting device in the form of a fuse for interrupting the charging current in the case of increasing the charging current over a predetermined threshold.

In accordance with the invention, this enables the redundant safety shutdown in the event of a charging error. The arrangement of the redundant safety shutdown in the charger, it is not necessary to differentiate between a charging current and a discharge current, which may exceed the charging current many times. The safety shutdown can be made more robust and reliable. The redundant safety shutdown means that even advanced and far-reaching safety standards can be met. Furthermore, a range of uses of the energy storage can be increased, for example, in sensitive areas such as human and veterinary medicine or in an explosive environment. Due to the design in the form of a fuse, the second interrupting device can be realized simply, inexpensively and functionally reliable.

In one embodiment, the second monitoring device is configured to cause a melting of the fuse in the event of a charging error. As a result, the second interrupting device can also be triggered when the charging current is not increased or only insignificantly above the predetermined threshold value. The firing rate of the fuse can thus be independent of how far and how long the charging current exceeds the predetermined threshold. The response of the melt This can be accelerated and made dependent on any measured values that indicate a loading error.

In one embodiment, the second monitoring device is configured to switch the fuse parallel to a current source to the

To cause melting. This power source may be, in particular, the rechargeable energy store, which can provide a much higher current than the power source, so that the fuse is cut quickly and safely. The existing functionality of the fuse can thus be used advantageously for interrupting the charging current due to any charging error.

Additionally or alternatively, the fuse may include a separate electrical activation element for independently triggering the fuse, wherein the second monitoring device is configured to switch the activation element in parallel with a current source to effect triggering. The triggering or melting of the fuse can thus be effected by means of a current whose potential is separated from the charging current. As a result, tripping safety can be further increased.

As a power source, a further energy storage can be provided. Thereby, the charging current can be interrupted even if the energy storage device does not have sufficient charge to melt the fuse and at the same time the current provided by the power source of the charger is not available or is not available for melting the fuse for other reasons.

The second monitoring device preferably comprises an interface to a third monitoring device arranged in the energy store, wherein the second monitoring device is set up to carry out the melting in response to a signal received via the interface. In a simpler embodiment, the signal may be provided, for example, by a sensor within the energy store. The sensor may be, for example, a temperature, current or voltage sensor. A sensor present in the energy store or an existing monitoring device with "intrinsic Intelligence "can be used in this way to accomplish the redundant shutdown outside of the energy store.

In general, a charging error may be present if at least one of a charging current, a temperature of the energy store, a temperature of the charging device and a voltage of the energy store leaves an assigned predetermined value range.

An inventive adapter is provided for charging a rechargeable electric energy storage device to a charger, wherein the charger is a

Power source with two power terminals for providing a charging current for charging the energy storage and a first monitoring device and an associated interruption device for interrupting the charging current in the event of a charging error comprises. The adapter comprises a second interruption device in the form of a fuse for interrupting the charging current in the event of the charging current rising above a predetermined threshold value.

Through the adapter, an existing charger of the type mentioned can be expanded to the charging device described above with redundant shutdown. A cost and resource-saving reuse of an existing charger can be made possible.

In a preferred embodiment, a first mechanical connection between the charger and the adapter and a second mechanical connection between the adapter and the energy store are incompatible with one another. Thereby, an operation of the energy storage can be prevented directly at the charger without the adapter, so that the redundant shutdown function can not be overridden. In addition, it can be prevented that the adapter is arranged against a predetermined orientation between the charger and the energy storage.

Brief description of the figures The invention will now be described in more detail with reference to the attached figures, in which:

1 shows a charging device with redundant shutdown function;

2 shows an embodiment of a fuse; and FIG. 3 shows an adapter on a charger and an energy store.

DETAILED DESCRIPTION OF EMBODIMENTS FIG. 1 shows a charging device 100 with redundant shutdown devices.

The charging device 100 is connected to an energy storage 105.

The charging device 100 includes a current source 110 having a first terminal 115 and a second terminal 120. The current source 110 is configured to provide a predetermined charging current between the first terminal

115 and the second terminal 120 to effect. The current source 110 comprises a first monitoring device 125 with an associated first interrupt device 127, which is set up to interrupt the charging current at the terminals 115, 120 if a charging error was detected by the first monitoring device 125.

For contacting the energy store 105, the charging device comprises a first contact 130, a second contact 135 and a third contact 140. The first contact 130 is connected to the first terminal 115 of the current source 110 by means of a fuse 145. The second contact 135 is directly connected to the second terminal 120 of the power source. A switching device 147 is configured to electrically connect the first terminal 1 15 to the second terminal 120 if a corresponding control signal of the second monitoring device 150 is present. The switching device 147 is controllable and may be constructed, for example, on the basis of a relay or a semiconductor switch. The second monitoring device 150 is set up to determine a charging error and then output a corresponding signal to the switching device 147. The second monitoring device 150 may itself determine the presence of a charging error due to measurements of, for example, a temperature, a current or a voltage. Furthermore, the second monitoring device 150 can be connected by means of a third connection 155 to the first monitoring device 125 in the current source 110 in order to exchange signals unidirectionally or bi-directionally, which indicate the presence of a charging error. In another embodiment, there is none

Connection between the monitoring devices 127 and 150 and the third port 155 may be omitted.

The energy storage 105 comprises at least one battery cell 160 and a third one

Monitoring device 165. The battery cells 160 are connected in series and connected to the first contact 130 and the second contact 135 as long as the energy storage 105 is connected to the charging device 100. The third monitoring device 165 is optionally operated with a voltage which is derived from the battery cells 160 connected in series with each other.

For monitoring individual battery cells 160, for example for determining a cell voltage, the third monitoring device 165 may additionally be connected to a single one of the battery cells 160. In a simple embodiment, the third monitoring device comprises

165 one or more sensors to determine, for example, a temperature or a cell voltage at one of the battery cells 160. In a preferred embodiment, the sensor arrangement 165 comprises a programmable microcomputer for the periodic or continuous monitoring of the Akkuzel- len 160 in different operating states of the energy storage 105th Die

Sensor arrangement 165 is connected to third contact 140 of charging device 100, while energy storage 105 is connected to charging device 100.

The second monitoring device 150 can be connected to the third monitoring device 165 of the energy store 105 by means of the third contact 140. be to unidirectionally or bidirectionally exchange signals indicative of the presence of a charging error. In another embodiment, there is no connection between the monitoring devices 150 and 165 and the third contact 140 may be omitted.

A further energy store 180, which may comprise, for example, an accumulator or a capacitor, is connected to the contacts 130 and 135 and to the second monitoring device 150. The further energy storage 180 provides energy that is required to actuate the switching device 147 if neither the energy storage 105 nor the power source 110 can perform this task.

In the illustrated embodiment causes the switching device 147, if it is activated, that the fuse 147 is connected in parallel to the energy storage 105, so that the flowing through the energy storage 105

 Short-circuit current brings the fuse 145 to melt, so that the charging current of the power source 110 is interrupted to the energy storage 105. At the same time, the switching device 147 connects the power connections 1 15 and 120 of the current source 110, so that the first monitoring device 125 determines a charging error in the form of an excessively high charging current and by means of the first

Shutdown 127 also shuts off the charging current.

In another, not shown embodiment, the further energy storage 180 can be connected by means of the switching element 147 so parallel to the fuse 145, that the fuse is melted by the electrical energy provided by the further energy storage 180, so that the charging current is turned off by the energy storage 105 ,

Fig. 2 shows an embodiment of the fuse 145 of Fig. 1. There are different fuses known having a fuse wire through which the current to be protected flows. If the current exceeds a predetermined threshold, the fuse is triggered by melting the fuse wire and breaking the current. Preferably, a fuse is used in the charging device of FIG. 1, which additionally includes a possibility of tripping independent thereof, so that the fuse can be triggered if necessary even if only little or no current flows through the fuse wire. For example, the fuse may include a chemical reaction element that is configured to expand upon electrical activation and break the fuse wire. The interruption can also be caused pyrotechnic and the electrical activation can be done by an electric heating element. FIG. 2 shows a further fuse which can also be used in the charging device of FIG. 1 with separate electrical activation.

The fuse 200 comprises a glass tube 205, at the opposite ends of each of which contacts of a first pair of contacts 210 and one of them electrically insulated second contact pair 215 are attached. The first pair of contacts 210 is connected to a fuse wire 220 that extends within the glass tube 205. The safety wire is sized in material, diameter and length so that it melts when it is flowed through by a predetermined current. In this case, a time that is necessary for melting, be determined in the form of inertia.

The fuse wire 220 is in the vicinity of a heating wire 225, wherein preferably there is no electrical contact. Preferably, the fuse wire 220 is wound by the heating wire 225. When a current flows through the heating wire 225, it heats the fuse wire 220 so that the fuse wire 220 melts.

In the charging device 100 of FIG. 1, the fuse 200 shown in FIG. 2 can be used such that with the aid of the switching device 147 of the heating wire 225 with the contacts 130 and 135, with the terminals 1 15 and 120 or with the terminals of the other Energy storage 210 is connected to cause melting of the fuse wire 220 and thus switching off the charging current through the energy storage 105.

FIG. 3 shows a further embodiment 300 of the charging device 100 from FIGS. 1 to 3, the charging device 300 being connected to the energy storage 105 from FIGS. 1 and 2. FIG. 3A shows an embodiment 300 of the charging device 100 in a lateral view. The charging device 300 comprises a charging device 305 and an adapter 310. The adapter 310 is arranged mechanically between the charging device 305 and the energy storage 105. Electrically, the charger 305 corresponds to the power source 110 with the first fuse 125 and the first one

Interrupt device 127 of FIG. 1, and the adapter 310 of the arranged between the terminals 115, 120, 155 and the contacts 130, 135 and 140 elements in Fig. 1. The adapter 310 extends the current source 110 of FIG. 1 to the charger 100 from Fig. 1, so that the charging device 100 according to the invention can be easily and safely created on the basis of the known power source 1 10.

The adapter 310 is configured to enter into a first mechanical connection 315 to the charger 305 and a second mechanical connection 320 to the energy store 105. In this case, the adapter 310 is designed in the region of the connections 315, 320 such that incorrect orientation or omission of the adapter 310 prevents operation of the energy store 105 on the charger 305.

3B shows in a first section AA of the charging device 300 from FIG. 3A a surface of the adapter 310 in the region of the second mechanical connection 320. FIG. 3C shows in a second section BB of the charging device 300 from FIG. 3A an opposite surface of the adapter 310 in the region of the second mechanical connection 315. Corresponding contacts or connections of the energy store 105 and the charging device 305 each have corresponding arrangements. Other embodiments of the adapter 310, not shown, may include other arrangements of the contacts or connections and / or other mechanical coupling elements that fulfill the purpose of the polarity reversal protection described below.

The illustrated arrangements of the contacts 15, 120, 130, 135, 140 and 155 ensure that the energy store 105 can only be charged on the charger 305 if the adapter 310 is arranged in the correct orientation between the energy store 105 and the charger 305 is. An internal distance between the first contact 130 and the second contact 135 of the adapter 310 in the region of the second mechanical connection 320 is large. than the outer spacing of the first and second contacts 115 and 120 arranged in the region of the first mechanical connection 315. The relative positions of the third contact 140 and the third connection 155 are far enough different in the vertical direction of the adapter 310 to ensure here as well. that the contact to the charger 305 or the energy storage 105 is only made when the adapter 310 is disposed in the manner provided between the energy storage 105 and the charger 305.

If the adapter 310 is placed on the charger 305 in the wrong direction, then the contacts 130, 135, 155 on the adapter 310 do not find electrical connection to the terminals 115, 120, 155 of the charger 305. In a corresponding manner, the contacts 130, 135, 155 of the energy storage 105, when it is placed on the wrong way around the charger 305 placed adapter, no electrical connection to the terminals 115, 120, 155 of the adapter 310th Wrd the energy storage 105 with the omission of the adapter 310 placed on the charger 305, Thus, for the same reasons also no electrical contact, so that the energy storage 105 can not be charged directly to the charger 305.

Claims

claims Charging device (100) for a rechargeable electrical energy store (105), comprising:  a power source (110) having two power terminals (115, 120) for providing a charging current for charging the energy storage device (105);  a first monitoring device (125) and an associated first interrupting device (127) for interrupting the charging current in the event of a charging error;  marked by  a second interruption means in the form of a fuse (145) for interrupting the charging current in the event of increase of the charging current over a predetermined threshold value. Charging device (100) according to claim 1, characterized by a second monitoring device (150), which is adapted to cause a melting of the fuse (145) in the event of a charging error. Charging device (100) according to claim 2, characterized in that the second monitoring device (150) is adapted to switch the fuse (145) in parallel with a current source (110) to effect the melting. Charging device (100) according to claim 2 or 3, characterized in that the fuse (145, 200) comprises a separate electrical activation element (225) for independently triggering the fuse (145, 200) and the second monitoring device (150) is adapted to the activation element (225) in parallel with a current source (1 10) to switch to cause the triggering. Charging device (100) according to claim 3 or 4, characterized in that a further energy store (180) as a current source (110) is provided is Charging device (100) according to one of Claims 2 to 5, characterized in that the second monitoring device (150) comprises an interface (140) to a third monitoring device (165) arranged in the energy store (105), the second monitoring device (150) thereto is arranged to cause the melting on the basis of a signal received via the interface (140). Charging device (100) according to one of the preceding claims, wherein a charging error is present when one of the following values leaves an assigned value range: the charging current, a temperature of the energy store (105), a temperature of the charging device (100) or a voltage of the energy store (105 ). Adapter (310) for charging a rechargeable electric energy storage (105) on a charger (100),  the charging device (100) having a current source (110) with two current connections (115, 120) for providing a charging current for charging the energy store (105) and a first monitoring device (125) and an associated first interrupting device (127) for interrupting the charging current Case of a loading error includes; and the adapter (310) comprises a second interruption means in the form of a fuse (145) for interrupting the charging current in the event of the charging current rising above a predetermined threshold. An adapter (310) according to claim 8, wherein a first mechanical connection (315) between the power source (110) and the adapter (310) and a second mechanical connection (320) between the adapter (310) and the energy storage (105) to each other incompatible.