WO2002052672A2

WO2002052672A2 - Storage battery with integrated detecton and indicating means

Info

Publication number: WO2002052672A2
Application number: PCT/GB2001/005620
Authority: WO
Inventors: Teng Cheok Khoo
Original assignee: Intelligent Battery Technology Limited
Priority date: 2000-12-26
Filing date: 2001-12-24
Publication date: 2002-07-04
Also published as: AU2002222264A1; WO2002052672A3

Abstract

There is disclosed a storage battery which is capable of self-monitoring by detecting and indicating the actual capacity of the battery, the condition of its charging system and discharge level. The battery is provided with an intregrally assembled detection and indicating means which measure the actual potential across its terminals. The battery is assembled to include a casing (2), a cover (3) and a capacity detection and indicating means. The detection and indicating means consist of an electronic circuit that measures electromotive force available in the battery and indicate the same on a display means (9). The display means is adapted to exhibit whether the battery is in a good working condition or otherwise during engine off or whether the charging system of the vehicle is in good working condition during engine in operation. Further, it could also monitor potential leakage presence in its electrical system.

Description

Storage battery with integrated detection and indicating means

This invention relates generally to an electrical storage battery and more particularly to a storage battery that is provided with a detection and indicating means. This invention also relates to a storage battery having capacity detection and indicating means integrally assembled thereto.

Electrical storage batteries are in widespread use. Such batteries are used in a wide range of applications including but not limited to automotive, powerboat, lighting, un- interruptible power supply (UPS) devices, and so forth. In the case of automotive applications, especially use private vehicles, there are occasions where an operator of the vehicle may encounter the problem of not being able to start the engine as a result of a weak battery. For example, this may be due if essential maintenance of the battery or its charging system has been neglected, or due to a simple error on the part of the operator such as forgetting to turn off the lights. A weak battery may also be caused by electrical leakage occurs in the vehicle's electrical system or within the battery itself that might cause the battery discharge.

Therefore, there may clearly be advantage to a user in providing a battery that has its own built-in capacity detecting and monitoring means. Such feature would allow a user to monitor the actual condition of the battery on a regular basis, and possibly receive advance notice of its imminent failure. Such a feature will also allow the actual capacity of a battery to be determined before it is sold, both to the advantage of a seller, as a form of quality-assurance tool, and to a potential buyer, who can assess the condition of the battery on offer.

The capacity of a storage battery may be determined by evaluating its charge level. Previously, there have been proposals to make such an evaluation by measuring the specific gravity of the electrolyte in the battery or by measuring the electrical potential across the battery terminals. Measurement of such specific gravity is usually done on an unsealed battery by performing measurement directly at the cells of the battery using a float hydrometer. Such a method of measurement cannot be performed on a maintenance-free type battery where the filling caps are sealed. Measurement of the specific gravity of a batter is generally a tedious operation, since the individual cells must be measures one-by-one, and can also be hazardous because of the presence of some potentially dangerous chemicals, including sulphuric acid, within the open battery cells. More importantly, the operator of a modern, low-maintenance vehicle would not normally be disposed to performing such an operation. Therefore, due to these disadvantages, in most cases the operation will simply not be carried out.

There has also been proposed apparatus for measuring capacity of a storage battery that operates by measuring the potential different between the terminals of the battery in a vehicle. The measurement is usually performed when the battery is in an open circuit condition. The result of this measurement can be converted into a battery percentage charge level, which provides an indication of the battery charge condition. There are some foreseeable problems if such testing apparatus and method are used. For example, periodic calibration must be performed to ensure accuracy, lost or misplaced apparatus during measurement and inconvenience because of the requirement of separate measuring device to measure the capacity of the battery. An integrally assembled measuring device would be of convenience.

An integrally assembled monitoring device to measure the operating condition of a storage battery has also been proposed before. For example, US-A-5 841 357 describes a battery electrolyte monitor that includes a one-piece monitor having a probe housing with its associated circuitry and connecting leads. The connecting leads may be permanently or temporarily attached to the battery electrical output. After removing the battery filler cap, the probe is inserted into the filler cap opening on the battery. The monitor's electrolyte level indicator provides an indication of the electrolyte level. If the indicator does not illuminate, electrolyte must be added to the battery. In another example, US-A- 4 913 987 describes a replacement for a conventional battery filler cap with a cap and a single wire and a sensor probe. Externally mounted circuitry monitors the voltage of the probe when it is immersed in the electrolyte. If the probe voltage drops below a predetermined value, the externally mounted monitor flashes an LED. Limitations on the accuracy and convenience of such known methods are apparent. There may be instances where most of the battery cells are in good working condition and only one or two are not. If it happens that such a measurement and monitoring device operates on a good cell, then the actual working capacity of the battery will be misinterpreted. It is not safe to deduce that the battery is in good working condition through measurement of just one cell; other cells may not be in good working condition, and this will affect the performance of the whole battery. If each of the filler caps were to be mounted with such apparatus, then costs are likely to be prohibitive.

Given the limitations of known devices, there is a need to have an integrally assembled detecting and monitoring device on a storage battery to assist the user in determining the actual electromotive force available or the potential across its terminals, and hence the actual capacity of the battery in an easy and most efficient manner. There is also a demand for an integrally assembled detecting and monitoring device that is also capable of monitoring the condition of the charging system to which a battery is connected.

The present invention seeks to offer a solution to the limitations described above.

It is proposed that a storage battery is to be provided with an integrally assembled detection and indicating means that measure and indicate the actual capacity or potential across its terminals in continuous manner. The indicating means is also of the type that is convenience to refer to, i.e. capable of indicating whether the battery is in good working condition or not during the engine off and whether the charging system of the vehicle is in good working condition or not during the engine in operation. Use of LED's is preferred for the indicating means along with other suitable indicators known in the art. Convenience in usage, accuracy in assessing the actual capacity of the storage battery and the ability to assess the condition of its charging system along with other benefits are some of advantageous that could be acquired through the present invention.

Accordingly, it is the an aim of the invention to provide a storage battery that is provided with an integrated detection and indication means to continuously monitor the actual capacity of the battery. It is another aim of the invention to provide a storage battery having integrated detection and indication means capable of continuously monitor the charging system condition where the battery is connected.

It is yet another aim of this invention to provide a storage battery that is provided with an integrated detection and indication means that also capable of monitoring and indicating its charging pattern in a convenient manner.

It is also an aim of the invention to provide a storage battery with an integrated detection and indication means that able to indicate whether there is a leakage in the electrical system or whether the battery is self-discharging.

These and other aims of the present invention may be accomplished by providing,

A storage battery having detection and indicating means integrally assembled thereto comprising;

a casing having an upper portion and a lower portion, at least a cell defined within the casing;

a cover fittingly enclosing the upper portion of the casing;

a pair of terminals mounted on the cover, each of the terminal is electrically connected to the corresponding anode and cathode of the cell;

characterised in that,

the detection and indicating means includes an electronic circuit, the electronic circuit being adapted to measure the electromotive force between the pair of terminals

(6) and compare the measured electromotive force with a pre-determined value set in the electronic circuit and correspondingly to indicate the condition of the storage battery based on the preset value on a display means (9).

Preferably, the detection and indicating means is configured as an electronic circuit.

Preferably, the electronic circuit is to be assembled and embedded within the cover of the storage battery. Also preferably, an optional communication means is provided to transmit logical signals generated by the electronic circuit to a remote display means. The generated signals may also be used as source for further processing by the engine management system of the vehicle.

It is also preferable that the battery is also provided with a carrying handle.

Yet, it is also preferable that the display means include use of a light emitting diode, a bar display device or a segmented display device.

In preferred embodiments, the detection and indicating means measures the total potential across all cells of the battery.

Embodiments of the invention will now be described in detail, by way of example, and with reference to the accompanying drawings, in which:

Figure 1 is perspective view of a storage battery embodying the invention;

Figure 2 is a perspective view of another storage battery embodying the invention;

Figure 3 is a diagrammatic representation of a storage battery having an integrally assembled capacity detection and indicating means embodying the invention;

Figure 4 shows the characteristic of electromotive force waveform in a vehicle battery during different vehicle engine conditions; and

Figure 5 is another diagrammatic representation of the battery embodying the invention together with its charging system.

Figure 1 shows a perspective view of a storage battery as proposed by the present invention. Generally, the battery (1) comprises of a casing (2) and a cover (3). The casing further comprises of an upper portion (4) and a lower portion (5). An upwardly extending internal wall (not shown) rises from the lower portion (5) to define an adjacently located cell (not shown). A single-cell type battery may also be possible. Normally, for automotive applications, a six-cell battery is common for a normal 12V storage battery. Positive and negative terminals (6) are also disposed on the cover. The terminals are correspondingly connected to each of the cells anode and cathode to provide the required voltage for the battery. The cover (3) may also be provided with a total of six inlet means (not shown), each inlet means correspond to each battery cell and the inlet means is used for filling or topping-up of electrolyte for the battery or, even an integrated unified venting assembly (also not shown) may also be used to provide a substantially maintenance-free battery. A handle (7) is pivotally mounted to the cover and the handle is capable of being folded or un-folded from its resting position. The handle is also capable of being flipped to its either side and to rest on the guide (not shown). Due to the feature of the handle, one hand operation for lifting of the battery is also anticipated.

As shown in Figure 2, the battery terminals (6) are disposed on the lowered section (8) of the cover (3) for a DIN (European) standard type battery. Such arrangement is particularly adapted for providing flush mounted battery terminals, which reduces possibility of a short circuit occurring if it happens that the bonnet of the vehicle comes into contact with the battery, for example, as the result of an accident. Alternatively, the terminals may also be mounted to the cover forming a raised terminal as commonly found on JIS (Japan) compliance battery, as shown in Figure 1. To eliminate the likelihood of a short-circuit, the terminals could also be slightly shortened. A display means (9), is also provided on the cover, such display means is advantageously used to display the actual capacity of the battery. Such a display means (9) would also help to display whether the battery is being charged sufficiently by the vehicle charging system while the engine is running. In effect, the system could also be used to monitor the charging pattern of the charging system during engine operation. Further, it is also able to detect whether there is any leakage is present in the electrical system to indicate that this has occurred. Normally, if the battery were not being charged sufficiently, then it could be presumed that the alternator of the vehicle is at fault or there is a fault in other components within the charging system. An electronic circuit capable of delivering such advantageous features is preferably assembled and embedded within the battery cover (3). The circuit operation will be discussed in detail later. An optional communication port (17), preferably to generate output signals according to the I2C communication protocol, is also provided on the cover (Figure 1, Figure 2). In this Figure 2, the handle for lifting the battery is not shown. Now referring to Figure 3, there is shown the diagrammatic representation (not to scale) of the battery having such an electronic circuit. As indicated earlier, the circuit is preferably embedded within the cover (3), mainly for its space saving and compactness. The display means (9) may includes use of a light emitting diode (LED), segmented display device or even bar display or any other suitable device known to those skilled in the technology. The display means is also preferably flush mounted to the cover so that it is flatly mounted to the same. If an LED is to be used, then preferably, at least three different illumination modes are provided, such as different colours, such as the red, yellow and green LEDs as depicted in Figures 1 and 2. Such three different colours of illumination correspond to three different levels of measured electromotive force available in the battery. While the engine is not running or during a low electrical load, a high potential across the terminals in a good condition battery will illuminate one of the LEDs, usually the yellow LED. Such high potential would be between 12.0 to 13.5 Volts. If the red LED illuminates, then this indicates that the battery is either weak or there is some electrical leakage in the system. Normally, the electromotive force of a weak battery will be at below 12.0 Volts. If the battery is found to be in a good condition and yet the red LED still illuminates, it may mean that leakage in the electrical system causes the battery to be self-discharging. This indicates that remedial action must be taken if problems are to be avoided.

While the engine is running, the system is used to detect and monitor the condition of the charging system. In particular, a fully operational charging system will illuminate the green LED because the illumination of such LED is set at above 13.6 Volts. If for some reason or another, the other LED were illuminated, then it would indicate that the charging system is at fault. It may mean that the alternator is incapable of charging the battery or there is a component fault in the system. As such, the charging pattern of the charging system could also be indicated on the display means. Moreover, a segmented display device capable of exhibiting the actual reading of the measured electromotive force could also be used along with bar display that correspond to the actual measured electromotive force in the battery.

To illustrate how such values are set as references to indicate the actual condition of the battery and its charging system, reference is now made to Figure 4, where the figure shows a characteristic waveform of the electromotive force in a good and fully operational storage battery during different stage of engine operation. For instance, while the ignition key is in the off position (A) or during open circuit or low load conditions, the potential across the terminals would normally be nearly 13.2 Volts, particularly just after the battery had been charged or after engine running. When the ignition is switched on (B), the voltage will drop to about 12.3 Volts, Therefore, a storage battery that is in good condition would normally have between 12.3 to 13.2 Volts of potential across the terminals. In such a situation, the yellow LED will be illuminated, because the yellow LED is set at such voltage range to be energised. During starting of the engine (C), the voltage across the terminals may drop to as low as 9.0 Volts and then rise steadily to about 15.5 Volts once the engine starts, depending on the ambient temperature. It will then slowly drop to about 14.0 Volts (D). It will remain more or less at this level during subsequent engine operation. In such situation, the battery is being charged by the charging system and the green LED will be illuminated to indicate that this is the case.

Referring back to Figure 3, the operation of the electronic circuit will now be explained. The circuit includes a regulated 5 Volts power section (11) to energise the circuit, a voltage and impedance reference section (12), an analogue-to-digital converter (13), a clock signal generator (14), a micro-controller (15), a decoder (16) and the display means (9). A communication protocol stage (17), preferably using I2C bus communication protocol, is also optionally provided to the circuit to transmit the processed signal to a remotely connected display panel or to the engine management system. The micro-controller (15) is used to process measured electromotive force in the battery in digital form and compare it with that of a predetermined values set in the micro-controller so as to provide the previously described details.

The electromotive force available in the battery will be represented as voltage and impedance values across the terminals. It is amplified by the operational amplifiers (18, 19) as analogue signals. The analogue signals from such amplification are then converted into digital signals by the analogue-to-digital converter (13). The micro- controller will compute and process such digital signals to provide an output that selectively energises the corresponding display means, so as to indicate the actual electromotive force available in the battery. As commonly known, a micro-controller normally includes a microprocessor, memory unit and an input/output. The predetermined values of reference voltages discussed earlier are set in the microcontroller itself through its operating software. A clock signal is provided by the clock signal generator (14) which preferably includes of a crystal oscillator for its inherent stability. The decoder (16) is used to decode logical data signals output from the microcontroller (15) to drive the display means (9) such that the illumination of the display means corresponds to the actual condition of the battery and the charging system as discussed above. As also indicated earlier, communication between the electronic circuit of the battery and a remote display panel or engine management unit is made possible via an optional I2C bus communication port which is preferably provided on the side of the storage battery. Such optional communication feature provides further convenience to the user, because the condition of the battery, by way of the display means, may be exhibited on the vehicle dashboard or at any other suitable location.

It will be readily apparent that a storage battery constructed as an embodiment of the present invention is convenient to use and its operational life might even be extended due to the continuous monitoring. This is in particularly the case if a fault were to occur because appropriate rectification measures may be taken promptly before any damage is done to the battery.

Figure 5 shows yet another diagrammatic representation of a battery that is connected to its charging system and in particular, the charging system of the vehicle where such battery is used. Further, as it can be seen in the drawing, a switch (20) is also included in the circuit to allow selective actuation of the detection and indicating means. Preferably, the switch is only actuated once the battery has been installed on the vehicle. This is in particular to reduce the possibility of energy being drained from the battery during its transport or storage. During engine operation, the charging system that normally includes an alternator (21), a full-wave rectifier (22) and voltage regulator (not shown) would generate at least 13.6 Volts across the battery terminals. In this situation, the green LED is illuminated to indicate that the charging system is fully-operational as indicated earlier. Any lower potential from the charging system would be detected by the system and indicated as a fault by illumination of one of the LEDs as discussed above.

While the preferred embodiments of the present invention have been described, it should be understood that various changes, adaptations and modifications may be made thereto within the scope of the claims.

Claims

1. A storage battery (1) having detection and indicating means integrally assembled on it, comprising;

a casing (2) having an upper portion (4) and a lower portion (5), at least a cell defined within the casing (2);

a cover (3) enclosing the upper portion (4) of the casing (2);

a pair of terminals (6) mounted on the cover, each terminal is electrically connected to the corresponding anode and cathode of the cell;

characterised in that,

the detection and indicating means includes an electronic circuit, the electronic circuit being adapted to measure the electromotive force between the pair of terminals (6) and compare the measured electromotive force with a pre- determined value set in the electronic circuit and correspondingly to indicate the condition of the storage battery based on the preset value on a display means (9).

2. A storage battery according to claim 1, further characterised in that the electronic circuit is also adapted to compare the measured electromotive force to the pre-determined value thereby indicating the condition of a charging system where the battery is connected.

3. A storage battery according to claim 1 or claim 2, further characterised in that the electronic circuit is adapted to process the measured electromotive force and on the display means (9), indicate at least, whether the battery is in good working condition or, the battery is not in good working condition or, whether the battery is being charged sufficiently by the charging system.

4. A storage battery according to claim 3, further characterised in that the electronic circuit includes use of a micro-controller (15) to process the measured electromotive force.

5. A storage battery according to claim 4, further characterised in that the electronic circuit also includes use of a regulated power source (11), a reference voltage and impedance (12), an analogue-to-digital converter (13), a clock signal generator (14), a decoder (16) and the display means (9).

6. A storage battery according to claim 5, further characterised in that the electronic circuit further includes a communication means (17) to transmit the processed signal to other display means remotely position from the storage battery.

7. A storage battery according to claim 5 or claim 6, further characterised in that the display means (9) includes a light emitting diode.

8. A storage battery according to claim 7, further characterised in that the light emitting diode is mounted flush with the cover (3).

9. A storage battery according to any one of claims 5 to 8, further characterised in that the display means (9) includes an electronic displaying device.

10. A storage battery according to any one of claims 5 to 9, further characterised in that the display means (9) includes a segmented display device for exhibiting measured value.

11. A storage battery according to any preceding claim, further characterised in that the electronic circuit is assembled and embedded within the cover (3).

12. A storage battery according to any preceding claim, further characterised in that a handle (7) is pivotally mounted and positioned substantially at the centre of the cover (3) for assisting lifting of the battery.

13. A storage battery according to any preceding claim, further characterised in that the storage battery is used in a motor vehicle, and the display means is adapted to indicate the condition of the battery during the engine off and indicate the condition of the charging system of the motor vehicle when the engine is in operation.

14. A storage battery according to claim 13, further characterised in that the electronic circuit also capable of detecting leakage of energy from the battery and indicating the same on the display means while the engine is not running.

15. A storage battery according to any preceding claim in which the detection and indicating means measures the total potential across all cells of the battery.