MXPA95003678A - Lead acid battery rejuvenator and trickle charger. - Google Patents

Abstract

A combination rejuvenator and trickle charger for lead acid batteries powered by a multi-solar cell unit and/or a rectified a.c. source, the output of which is applied to a capacitor. The output of the capacitor is in turn connected across the primary of an auto transformer. A switching circuit, including a transistor, connects and disconnects the primary coil to and from the capacitor to produce in the secondary coil of the transformer a fast rise time current pulse for application to a battery. A positive temperature coefficient resistor is connected in series with an output terminal of the rejuvenator to protect the rejuvenator components in the event the out, put terminals, through accident or mistake, are connected to battery terminals of opposite polarity.a.

Description

REJUVENATE THE LEAD ACID BATTERY AND SLOW LOAD DEVICE '¡fr * DESCRIPTION OF THE INVENTION 1.- Field of the Invention. This invention relates generally to battery chargers and more particularly to a lead acid rejuvenator with acid that works in both sunlight and dark. 2.- Previous Technique. , ^ j During the use of lead acid batte, P 'the lead sulphate deposits are formed slowly on the plates to partially cover the spongy lead and the plaque surfaces of the lead oxide. Then the sulphates crystallize and offer a high impence to the flow of dashes thus reducing battery efficiency. The recharge with low direct current is ineffective to dislodge the sulphate deposits.

For many years, efforts have been made to dislodge these deposits by a rapid loading technique that it generally overheats and accompanies the batter plates. Although a battery may appear to have taken a charge and an electrolyte may be verified as correct, but the battery does not retain the charge because the plates have been shortened effectively. Efforts have been made using voltage points of rapid rise in time for release the sulfates from the surfaces of the battery plate / j so that the loose sulphate will go to the solution or drop to the bottom of the battery case. Such a technique is described in US Pat. No. 5,084,664 issued to Cari E. Gali and entitled "Lead acid battery rejuvenator and solar powered slow charging device". Although the present invention has some of those characteristics pointed out in the previous patent, this is a more efficient, more flexible and more effective technique for removing the deposits of lead sulfate from the battery plates, in order to increase the service life of the batte. of lead with acid. SUMMARY OF THE INVENTION The present invention provides a combination of rejuvenator and slow charge for lead acid batte comprising in one embodiment, as source of the supply voltage, a unit of multiple solar cells. In another mode, the voltage supply is It provides for a converter that converts alternating current to direct current. In one embodiment using solar cells, four cells are connected in se, each producing approximately half a volt. The energy from the four cells is therefore two volts, the output of the solar cells are applied to a capacitor whose output is connected through the primary of a transformer. In a preferred embodiment the transformer is a self-transformer. A switching circuit including a transistor connects and disconnects the primary coil to and from the capacitor to produce in a secondary coil of the transformer a current pulse of rapid rise in time to be applied to a battery. The operation of the transformer together with the switching circuit is equal to a horizontal output transformer. The Turning or turning ratio of the transformer can have a range of 6 to 18 depending on the functional voltage of the battery to be treated by the rejuvenator and the slow charger, that is if the battery is 12, 24 or 36 volts . The exit of the rejuvenator can be applied to battery terminals by means of an inert plug in a ^. Cigarette lighter located on a vehicle or applied to an extension and plugs to connect directly to the battery terminals. A positive coefficient resistor is connected in se with one of the terminals to protect the rejuvenator in the event that the output terminals due to inadvertence, accident or error are connected to the battery terminals by opposite side.

Sulfates form more quickly when the battery is at rest as when a car is I5- parked to a garage or boat this moored in a covered entrance of a dike for a long period of time. In these situations when the incident light is minimal, care must be taken to connect the rejuvenator and the slow charge device to a direct current source that can take the form of a converter fitted to a local source of alternating current. So the rejuvenator and the slow charge device of the present invention works with sunlight as in the dark. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic circuit illustrating the details of the rejuvenator and the slow charge device of the present invention. Figure 2 illustrates the outgoing shape of the current wave of the schematic representation of the X Figure 1. Figure 3 illustrates the outgoing waveform of the schematic circuit voltage of Figure 1. DETAILED DESCRIPTION Referring now to the drawings, a power source for the rejuvenator and the slow charger 10, is shown comprising an array of solar cells 12 including four solar cells 12A, 12B, 12C, and 12D, each cell is capable of producing an output voltage of r ^ approximately 0.5 volts and therefore the output of the bank voltage or array of four solar cells will be 2.0 volts. Another power source 50 is shown to be connected in parallel with the bank of solar cells when the battery is in a dark environment. The current output of solar energy depends on the amount of the last incident on the cell. for ?? a level of incident light given by a solar cell produces 250 milliamps. Above 250 milliamps the voltage produced falls rapidly. Down 250 milliamps the output voltage is fairly constant. The output of the bank of solar cells 12 is applied via the conductors 14 and 16 to a back-off output network comprising the transformer 18 and the switching transistor 20 operating the transistor 20 and conducting, the current flows from the capacitor through the of the primary coil 22 of the transformer 18 to magnetize the transformer core the direct current flowing to the capacitor 18 from the bank of solar cells until the voltage of the capacitor reaches the maximum output voltage of the solar cell bank 12. The voltage across the capacitor 18 is recorded by a network including the switching transistor 24 the switching iod 26 and the resistor 28. The transistor 24 turns on or operates when the measured voltage reaches the value Von. The value of the voltage Von can be expressed as; Von = V e + Vf Ib2R28 where; Vbe; base-emitter voltage of triode 24. Vf, - fallen in front of diode 26 Ib2? the basic driving current of the triode 24 R28? resistor resistor R28 When operating the switching transistor 24 turns on the transistor 20 and these transistors remain working while transferring power from the capacitor 18 to the primary of the transformer 19. When the voltage of the capacitor 18 falls below the value required to sustain a drive of minimum base current for transistor 20, the two »transistors 20 and 24 are turned off. The value of the voltage at which the transistors are turned off, V0 can be expressed as follows; Voff = 2 X Vsat + Ibl R30 where; vsat? saturation voltage of transistor 20 or transistor 24; Ibi; Drive current of bas for the transis tor 30; R30 'resistor resistor 30. When voltage V0 has been achieved, the . switching commutator 20 turns off the voltage ,? flows back to the secondary 32 of the transformer 19 at a value determined in part by the load that includes the battery (not shown) and the diode 34, together with the ratio d twist or turns of the secondary coil of the transformer with respect to the coil primary . By an adequate selection of the proportion d Turning the back-to-back voltage can be used to charge either a 12-volt, a 24-volt or a 36-volt battery. The backward return voltage causes 1 diode 34 to drive forward and the current transferred by the induction on the secondary of the transformer 19 to a battery that will be connected to terminals 36 and 38 of circuit 10. The character of the current produced in the form of high frequency pulses illustrated in Figure 2. The waveforms representative of the current pulses in Figure 2 were obtained through a resistor load of 10 ohms, it will be observed that the current growth time It is quite respectable and then falls on steel in approximately 42 microseconds. The current pulse reaches its maximum at 60 mollia ps and has a rate of repetition of 8,333 kilo hertz. The character of the pulses of voltages produced is illustrated in Figure 3 where '^ * The voltage is shown to rise rapidly when the switching transistor turns off, at a value of approximately 20 volts. The value of the voltage point drops very slowly until the current value reaches 0 where the voltage will drop exponentially and eventually reach 0 in approximately 52 micro seconds. The maximum pulse current produced by the k? J circuit 10 is greater than the leakage discharge current in a car battery. The effect of this is that a small average load current can be effective to reduce or eliminate the sulphate formations. on the lead acid plates with acid over a long period of time. Therefore, the battery will retain its ability to provide start-up current over a long period of time and can be recharged quickly ^ by a high current charger. The gentle detachment of the sulfates on the plates of the battery in use of the present invention will allow the recovery and subsequent recharging of still-old batteries otherwise no longer usable. A visual indication that the circuit 10 is operating is provided by a light emitting diode (LED) 40 connected in series with the positive terminal 36.

The different components of the circuit 10 are protected against an inadvertent connection of the terminals 36 and 38 to the terminals of the battery of opposite polarity. When such erroneous connection arises, a high current draw would occur which would pass through diode 34 damaging the components of the rejuvenator 10. The resistor 42 is provided to protect the components of the rejuvenator 10 from current floods that could result from an error in connecting the terminals 36 and 38 to the battery posts of the battery. # opposite polarity. The resistor 42 is connected in series with the diode 34 and the positive terminal 36. It is a resistor d positive current coefficient whose resistance increases markedly at a rather low temperature. This "change in resistance occurs rapidly and causes the current to drop to a level or levels that can be tolerated by different current components. The components r ^ dominally can tolerate a current of one ampere. The LED 40 protection of the current floods is realized by a plurality of diodes 44 connected in series in turn connected in parallel with the LED 40 these diodes offer a very low impedance to the current flow. In the case of a wrong connection of the terminals most of the current will flow to through the diodes 44 to the resistor 46 of the positive temperature coefficient. In addition protection for the bank 12 of solar cells is provided by the inclusion of a diode 46 to prevent the flow of current to the solar cells when the terminals 36 and 38 are connected to the rear of the battery terminations. The outlet of the rejuvenator 10 can be applied to the terminals of the battery by means of a plug connected to the output terminals 36 and 38 and inserted in the cigar lighter in a vehicle.

# In alternative the output of rejuvenator 10 can be applied by means of an extension and plugs to connect directly to the battery terminals. In this last alternative the connection would be a mistake in connecting the output of the rejuvenator to the battery will be treated. The identification of some components used in a prototype of the present invention, are the following; Transistor 20 is the power transistor TIP41A from Texas Instruments. Transistor 24 is a PNP 2N4403 transistor from Motorola. Diodes 34, 44, 46 are Motorola's 1N4001 silicon rectifiers.

The diode 26 is a Motorola 1N4148 commutator diode. The resistor 42 is a resistor coefficient d positive temperature 232266111211 of Phillips. The other power source 50, it must be connected when the battery is in a dark place and it is shown that it comprises a direct current alternating current converter 52. The converter 52 can be connected to a local alternating current source usually 115 volts through the middle of the plug 54 to produce a direct current voltage at its output 56. The direct current voltage is received by the rejuvenator and the slow charge 10 by means of a plug 58 connected in parallel with the bank of solar cells by the connectors 60 and 62. The converter 52 is commercially available and is typically of the type used in portable radios by portable calculators and the like. In a constructed prototype of the present invention P1 the converter 52 has an output of 7.5 p ^ volts and 300 amps. While the parameters of the rejuvenator and the slow charge device 10 require a direct current source of 2 volts, the resistor 64 with a value of 18 ohms was added in series with conductor 62 to lower the voltage to two volts at 300 5 milemperes. When the parameters of the rejuvenator and the loading device 10 are changed by the use of Mosfet elements,] the output of the source 50 can be changed. Although the invention has been described as a special embodiment, there are many modifications and changes, for example the number of solar cells in 1 bank 12 could be reduced to one with the use of Mofet transistors that are operable at lower voltage levels. for example half a volt.

Claims (13)

1. NOVELTY OF THE INVENTION Having described the present invention as - foregoing, the content of the following is claimed as property; CLAIMS 1.- "A combination of rejuvenator and slow charged device for lead acid batteries comprising: a first source of direct current voltage, a capacitor connected through the source, a transformer having a first coil connected to the capacitor, and a second coil, a connector circuit that includes a transistor which connects and disconnects the primary coil to and from the capacitor to produce in the second coil a pulse of rapid rise in time to apply
2. . 2. Rejuvenator according to claim 1, to connect the first source in parallel, with a second source of direct current voltage.
3. 3. The rejuvenator according to claim 1, where the transformer is a self-transformer.
4. 4.- 'Rejuvenator according to claim 1 ,? in where the transformation has a plurality of turns with more turns in the secondary coil than in the primary coil in the order of 6 to 18.
5. 5. Rejuvenator according to claim 1, which includes a second transistor that responds to the voltage across the capacitor to change the transistor to first run or non-run.
6. 6. Rejuvenator according to claim 1, which includes output terminals and a resistor of effective temperature coefficient j &_ in series with one of the terminals to protect the rejuvenator in the case that the terminals are connected to terminals of the battery of opposite polyrality.
7. 7. The rejuvenator according to claim 5, wherein a light-emitting globe connected in series with the positive temperature coefficient resistor is included to visualize the operation of the rejuvenator.
8. 8. Rejuvenator according to claim 1, what . £ includes at least four solar cells connected in series.
9. 9. Rejuvenator according to claim e, wherein the second source is a direct current alternating current converter.
10. 10.- A combination with rejuvenating solar energy and slow charge device with batteries of lead comprising; a bank or arrangement of four solar cells' flr connected in series an alternating current to direct converter in parallel with the solar cells; a capacitor connected through the bank of solar cells, and a transformer that has a primary coil connected through the capacitor and the secondary coil; a switching circuit that includes a first tXs;. transistor that connects and disconnects the primary coil to and from the capacitor to produce in the secondary coil a current pulse of rapid rise in time to be applied to a battery, and a second transistor connected to sense the voltage of the capacitor to change to the first transistor a state to the otor; a pair of output terminals to connect to terminals of a battery; a light emitting diode connected in series with ^ * one of the terminals for a visual signal of the functionality of the rejuvenator, and a respective coefficient resistor connected in series with the terminals where the light emitting diode protects the rejuvenator in case of that the output terminals are connected to battery terminals of opposite polarity.
11. 11. Rejuvenator according to claim 10, in where the transformer is a transforming car.
12. 12. Rejuvenator according to claim 10, wherein the transformer has turns with more turns in the secondary coil that the turns of the primary coil in the order of 6 to 18.
13. 13. Rejuvenator according to claim 10, which includes a plurality of diodes connected in seri which are connected in parallel with the light emitting diode to provide a low impedance path V «gs.- to protect the light-emitting diode in the case of the output terminals that connect to battery terminals of opposite polarity. F