FORM-2
THE PATENTS ACT, 1970
( 39 of 1970 )
PROVISIONAL / COMPLETE
SPECIFICATION
SECTION 10
TITLE
LEAD ACID BATTERY CONDITIONER

APPLICANT

ECOSOLAR SYSTEMS (INDIA) LTD., 117/A/2 Pune-Sinhagad Road, Parvati, Pune 411 030, Maharashtra, India

The following specification particularly describes the nature of the invention and the manner in which it is to be performed

The present invention relates to a lead acid battery conditioner and particularly a pulse charger useful for conditioning lead acid batteries.
Lead acid batteries are well known for its various use in automobiles and in other areas.
Lead acid batteries are the most commonly used batteries. The main reason for this is that the energy storage density is quite large and it is capable of giving large energy pulses for a short time without suffering any damage. The second reason for
popularity is that it can be easily recharged to bring it back to almost in new condition. The lead acid battery has a number of cells made of two different type active materials, namely lead dioxide (PbO ) and sponge lead :ide semiconductor field effect transistor or a insulated gate bipolar transistor.
The invention described herein is about a pulse charger for conditioning of the lead acid batteries- The power sources used are solar cells. These are used to generate pulses. When these pulses are given to the battery, the lead sulphate crystals formed on the plates are broken and dissolved back in the acid.
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The pulse has linearly rising current, followed by its substantially linear decay in the initial stage and an exponential decay later, finally reaching zero. The frequency is variable in steps from about 3 to 6 kHz- A thermister is also provided. Thermister is a positive temperature coefficient resistor which increases the resistance drastically to limit the current and thereby the heating or damage to the battery. The pulse charger would be operative only when the ignition key is off resulting in engine not running. As soon as the key is inserted and engine started, the pulse charger would be

automatical ly turned off.


The present invention provides a lead acid battery conditioner

comprising an el ectronic switching circuit, a source of power supply, said electronic circuit cbrnprises a timer, said battery conditioner further comprises an invertor, one or more capacitors and at least one transistor. The said lead acid battery further comprises a power supply, a pair of transistors, one or more capacitors, an investor, a transformer, a thermistor and a diode.
In the above lead acid battery conditioner, the power supply is a solar cell or any other electrical power supply that generates a pulse train.
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In said lead acid battery, the transistor is selected from a metal oxide semiconductor field effect transistor and an insulated gate by bipolar transistor. The thermistor is a posi tive temperature coefficient resistor capable of increasing the resistance drastica1ly to limit the current and thereby heating or damaging the battery.
In the improved lead acid battery the supply of pwoer is obtained from a grid.
The invention uii 11 now be described in detai 1 with reference to
the drawings accompanying the' provisional'specification.
In the drawings, the lead acid battery conditioner is i1 lustrated
in detail and it comprises a solar cel 1 <1), a pair of transistors (2), a timer <3) one or more capacitors <4> an inverter (5), a transformer (6), a thermister (7), a diode (8) and an interlocking ignition switch (9). The capacitor (4) is charged during one part of the cycle and is discharged through the transformer (6) in the second part of the cycle. The transformer (6) is used to boost up the voltage of the pulse to the desired level required for the battery. Both the timer and the inventer are adapted to ensure alternative operation of switching for charging and discharging circuit. The transistor (2) may be a metal oxide semiconductor field effect or insulated gate bipolar transistor or bipolar junction transistor. The said

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transistor is used to ensure that the power loss in the transistor is low and at the same time the energy used to operate said transister is also very low. The timer (3) is used to give a variable frequency of charging and at the same time reduces the loss of watt in the control circuit. Since the unit is operating on solar power, the thermister (7) is provided to protect the unit and battery if any connection is made wrongly.
The sequence of operation can be described starting from the time the ignition keg is turned off thereby turning on the switch control ling the circuit .This would start the charging of capacitors (1 ) and <2) Once the capacitor., (1) is charged it would give energy to timer and in verteri. This would close

transistor (1 ) and the charging of capacitor (3) would start. Af ter the an time is over, the transition (i) would be switched off and transistor (2) would be switched on. This would short the capacitor (3) through the transformer winding. The transformer would step up the pulse to the required voltage and send it through the diode and thermister to the battery. After the cycle time, transistor (2) would be switched off and transistor (1) would be switched on and the cycle would start again.
The operation would show the di fferences between the new design of the battery charger and the existing design. In the existing design a flyback circuit is used which charges the capacitor to a threshold value. As soon as the threshold value is reached the
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A lead acid battery conditioner uses the pulse train signal that has a substantially linear rise from a zero voltage level as a first step, followed by a substantially linear decay in voltage at a rate much slower than the rate of rise- The current signal follows the pattern of the voltage signal. After linear decay, when the voltage has reacted a certain level, the further decay of the voltage to the base level is exponential. The current waveform follows the voltage waveform.
The base voltage level is zero volt and base current level is
zero amp.

The pulse train is then transformed to the dessired voltage for

the battery and is applied to,the termi-nals of the battery.
The transformer is done using a transformer having a primary coil and a secondary coil- The secondary coil is for delivering the power to the battery at the required voltage.
A lead acid battery conditioner forces a current pulse through the battery. The amplitude and frequency of the pulse is selected so as to introduce dislocation in the lead sulphate crystals. These dislocation lines in the crystal enable the crystals to break into smaller crystals and dissolve in the battery acid. A lead acid battery conditioner includes a positive temperature coefficient resistor connected in series between the terminal of the diode in secondary circuit of the coil and the terminal for
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connecting the positive electrode of the battery. This ensures that the battery does not get discharged and damaged even if connected to the charger in the reverse direction.
It gives the pulse signal at a frequency of 3 to 6 kHz. The variable frequency is useful to dislocate the variety of lead sulphate crystals formed on the lead plate. The frequency can be set at the descired level between the two limits of 3 to 6 kHz by the customer. It is provided with the interlock to ensure that either the signals of pulse charging or the spark-plug firing signals do not work simultaneously to produce any interference in the operation of the other signal.
The lead battery conditioner as a described' herein and as
illustrated in the drawings;, is by way of an example. Any

improvement or obvious modification of such lead acid battery

conditioner will be within the knowledge of a person skilled in
the art and is covered by this invention.

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WE CLAIM:
1. A lead acid battery conditioner comprising an electronic switching circuit, a source of power supply, said electronic circuit comprises a timer, said battery conditioner comprises an inverter, one or more capacitors and at least one transistor, wherein said power supply is preferably a solar cell or any other electrical power supply that generates a pulse train.
2. A lead acid battery conditioner as claimed in Claim 1 which comprises a power supply, a pair of transistors, one or more capacitors, an inverter, a transformer, a thermistor and a diode.
3. A lead acid battery as claimed in any of the preceding claims wherein said transistor is selected from a metal oxide semiconductor field effect transistor and an insulated gate bipolar.
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4. A lead acid battery as claimed in Claim 3 wherein said thermistor is a positive temperature coefficient resistor capable of increasing the resistance drastically to limit the current and thereby heating or damaging the battery.
5. A lead acid battery as claimed in any of the preceding claims wherein the supply of power is obtained from a grid.
6. A lead acid battery substantially as herein described and as illustrated in the drawings accompanying the Provisional Specification.
Dated this 6th day of May 2002.

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