solar powered bycycle

7/29/2019 Solar Powered Bycycle

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ABSTRACT

A method of upgrades a conventional electric powered bicycle over to Solar-

Powered Electrical Bicycle that is powered by an electric motor which gets its

supply from photovoltaic (PV) panels. The PV panels must be mounted and

installed at the electric bicycle without compromising riding comfort ability. The

method employs a small electric motor that are easily connected and separated for

ease of transport. A solar collector is connected to the rechargeable batteries for

collecting solar energy and converting such energy to electrical power that is

delivered to the rechargeable batteries for recharging thereof. A rechargeable

battery is operable connected to DC motor for providing electrical power to drive

the motor.


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INTRODUCTION

1. INTRODUCTION:

In many developing countries there is much larger potential for renewable

like wind and solar energy then in industrialized countries. According to the

International energy Agency (IEA), 13.5% of the worlds total primary energy

supply (TPES) is produced by renewable sources of energy. In the case of

traditional biomass, the energy source (in general, this wood) can often not be

classified as renewable, especially in the arid and semi-arid regions of the world.

In the case of large hydropower plants, extensive areas of land often have to be

flooded, destroying biodiversity, habitats and forcing the local population to

resettle. The so-called new renewable energy, geothermal energy, modern

biomass, small hydropower and ocean energy, have a much smaller impact on the

environment and the social structures and can therefore contribute to a largerdegree to a truly sustainable development.

In our project we use solar energy is converted into electrical energy. It is

stored in the lead acid battery and the power supply is supplied to the micro

controller kit. The signal is sent to the ultrasonic sensor from the kit and the fuel

level is detected and displayed in the LCD. Therefore the main theme of the

project is to operate the grinding machine.


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2. LITERARY SURVEY:Man relied mostly on the sun for his energy needs. With the increasing in

population of the world and especially our country, coupled with the desire for

higher standard of living and better quality of life, it is comparative that the basic

energy needs are met.

However, about 250 years ago, the picture changed radically by the

invention of steam engine and the increasing use of fossil fuels for producing

electricity and for industrial purposes. The recent rapid escalation in the cost fossil

fuels, the awareness regarding environmental pollution issues, the finite size of the

fossil resources, and the ever increasing demand to satisfy better standard of living

resulted in harnessing alternate energy source to supplement and eventually replace

fossil fuels. This is a rediscovery of mans old concern. The number of

conceivable ways to collect, store, convert, distribute were carried out and finally

the use of solar energy to immense.

The origin to the solar energy utilization was initiated in the year 1800 by a

scientist Mr. CHARLES FITTIS. The invention of light meter which is used for

determining the intensity of light was the initiative for solar energy utilization.

This meter was used in the field of photo graphics. This was implemented in

practice at the year 1930.

Later in 1954 the bell laboratories of U.S.A. made a research in generation

of electricity without any moving parts by using the principle of light meter. They

were successful in that research and there came the generation of electricity

without any moving parts, where sunlight was the main source for energy for

generation of electricity.


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In order to effectively harness the solar radiation one must know the spectral

distribution of sunlight to evaluate absorbing by the atmosphere and near by terrain

and the types of instruments used to measure different aspects of the solar flux

Direct photo voltaic conversion of sunlight to electricity is a very enticing

prospect for clean production of electric power. This method is based on the use of

solar cell. The transfer of energy from the photons of solar light directly to

electrons in a potential semi conductor barrier layer without an intermediate

thermal step is the photo voltaic effect

The principle of the photo voltaic effect is closely associated with the theory

of diode and an introduction to the essential principle of the elements of

semiconductors physics is helpful in understanding the harnessing of solar energy.

Useful applications vary from production of few watts to several mega watts. It is

successfully exploited both in space and small scale applications on earth.

GLOBAL SOLAR RADIATION:

The performance of any solar system requires information on the availability

of energy in direct beam, diffuse energy from the sky or the reflected energy from

the ground and other objects.

For empirical estimation, solar radiation of possible sun sine and cloud are

used from meteorological exist data, and at location where no measured data a

linear interpolation is made by using total horizontal data from the nearest location.


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SOLAR RADIATION DATA:

Many countries through networks under meteorological organizations record

and maintain solar radiations data mostly in long leys received on a horizontal

surface in different observations centers. Data are available for daily or hourly

solar radiation, wind velocity, temperature and duration of sun shine and

cloudiness for over three decades.

This information are available in different forms and they are to be used

carefully because the records may provide bean, diffuse or total radiation,

instantaneous values integrated over an hour in a day, measurements in incline or

fixed slope or normal, daily measurements averaged by month and hourly average

by month.

Average solar radiation data provide information about general trends.

Based on accurate values of daily means of solar radiation at one location, solar

radiations for every month in different parts of the world are compiled. The daily

average total fluxes for sunlight on a horizontal surface for the month of June, in

various parts of the world are given.

The greatest amount of solar energy is found around the earth between the

15 degree and 35 degree north and south parallels, where there is a minimum

monthly mean radiation of 20 MJ/m2/day. These regions are on the equatorial side

of the worlds and deserts. In some of the areas there is usually over 3000 hrs

sunshine/year, over 90% of which come as direct radiation

The next favorable region for solar energy applications is in the belt between

15 degree north and 15 degree south parallels. The scattered radiation is high with

about 1500 hrs sunshine/year. The influx of solar radiations ranges from 12 to 20

M/J/m2/day. Between 35 degree and 45 degree parallels, at the edge of deserts the


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solar radiation averages 16 to 20 M/J/m2/day. The regions beyond 45 degree north

to 45 degree south are limited in their year-round direct use of solar energy.

More than 80% of the worlds inhabitants live between 40 degree latitude in

about 14 M/J/m2/day. In UK the average daily total solar radiation is about 16

M/J/m2/day, in summer and about 2 M/J/m2/day in winter. The total on a

horizontal surface is about 3500 M/J/m2/year. On the other hand, Australia which

is enjoying quite the opposite weather and vegetation receives about 6500

M/J/m2/year nearly twice as much.

Because of the inclination of the earth axis to the plane of its orbit, the

maximum altitude of the sun and the length of the day vary substantially with

latitude and season. This effect can be seen in the measurements of solar radiation

over the seasons for various latitudes. In summer they are compensating so that

the clear day the total energy falling on a horizontal surface is 30 6500 M/J/m2/day

at all latitudes up to the polar area.

The distribution of the total duration of bright sunshine in India ranges from

2500 to 3600 hrs/day. The global solar radiation of nearly 27 6500 M/J/m2/day is

available on a horizontal surface over arid and semi arid regions. During monsoon

and winter months the global solar radiation falls to 10 to 20 6500 M/J/m2/day.

Nearly 10% of area of the country receives global radiation exceeding

206500 M/J/m2/day and about 70% of the area 17 to 20 6500 M/J/m2/day. These

are favorable regions for harnessing solar radiation.

The desert Zones of the earth are having highest insulation. Arid and semi

arid regions of the country comprise 10% and 30% respectively of the area of the

whole country.


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Component and Description:

ELECTRICAL COMPONENT :

Solar Panel : 5 Watts

D.C. Motor R.P.M 1500

Solar Panel:

A solar cell works on the principle of photo voltaic principle, the photo

voltaic solar energy conversion is one of the most attractive non conventional

energy sources of proven reliability from the micro to the Mega watt level.

Pic. i) SOLAR PANEL

Project Background:

A method of upgrades a conventional electric powered bicycle over to Solar-

Powered Electrical Bicycle that is powered by an electric motor which gets its

supply from photovoltaic (PV) panels. The PV panels must be mounted and

installed at the bicycle without compromising riding comfort ability. The method

employs a small electric motor that are easily connected and separated for ease of

transport. A solar collector is connected to the rechargeable batteries for collecting

solar energy and converting such energy to electrical power that is delivered to the

rechargeable batteries for recharging thereof. A rechargeable battery is operable

connected to DC motor for providing electrical power to drive the motor.


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Problem Statement:

There are several problems that occur during upgrades a conventional

electric powered bicycle to Solar-Powered Electrical Bicycle. The specifications of

photovoltaic (PV) panels must be sufficient to generate the electric motor same as

a conventional electric powered bicycle. The suitable connection of solar cells,

rechargeable battery and DC electric motor with bicycle needed to make sure this

project accomplish with more optimum energy use. The electric motor must to

support the weight and size of the bicycle, size of solar panel and condition of the

road surface.

OBJECTIVE:

The objectives of this project are:

1. To upgrade a conventional electric powered bicycle to Solar-Powered Electrical

Bicycle that can be used for leisurely rides.

2. To design and develop Solar-Powered Electrical Bicycle which gets its supply

by using solar energy from photovoltaic panels.

3. To study the connection between solar cells, rechargeable battery and DC

electric motor.

4. To compare the characteristics and performance between Solar-Powered

Electrical Bicycle and electric powered bicycle.

Scope of project:

The scope of this project is to design and develop a Solar-Powered Electrical

Bicycle that is powered by an electric motor which gets its supply from


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photovoltaic (PV) panels and partially uses solar energy. This project will focus on

how to apply the photovoltaic (PV) panels on the electric bicycle in term of:

1. Speed of a Solar-Powered Electrical Bicycle compared to electric powered

bicycle.

2. Performance of DC motor Solar-Powered Electrical Bicycle compared to

electric powered bicycle. Because of the high-cost to develop an actual size of

ordinary electric powered bicycle, the size of the electric powered bicycle will be

scale-down to (1: 4). The prototype dimensions of the electric powered bicycle is

about length (0.64 meter) x width (0.33 meter) x height (0.33 meter). The unlade

weight about 2 kg (4.4 lbs) and the load that can be support is about 25 kg (55.11

lbs). Below are the full characteristics and specifications of the Solar-Powered

Electrical Bicycle project.

Theory Specification:

Actual size specification of electric powered bicycle:

Bicycle dimensions: Length 1.7 meter x Height 0.97 meter

Motor type: DC Motor

Calculation Specification:

Scale-down size (Actual size: Project size) = (1: 4)

Scale-down size specification of electric powered bicycle prototype (1: 4):


Motor type: DC Motor.

Prototype specification of electric power red bicycle:


Unlade weight: 2.5 kg (5.51 lbs)

Maximum load: 25 kg (55.11 lbs)

Motor type: DC Motor.


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LITERATURE REVIEW

Introduction:

This chapter will be stressed on the literature review of related system. The

main purpose of this chapter is to analyze, identify and make conclusion based on

the research. A literature review means a collecting related data, analyzed business

process, identify underlying patterns and create the conclusion (Strauss & Corbin

1990). Another description of the literature review is a systematic, explicit and

reproducible method to identifying, evaluating and synthesizing the existing body

of completed and recorded work produced by researcher, scholars and practitioners

(Fink, 2005).

In order to develop a successful project, the current systems are identified. The

system of conventional electric powered bicycle, solar system and its connection

have been analyzed. Studies of these systems are significant to develop a valid,

reliable and efficient upgrade project. The Literature Review part acts as a mean to

d is cover which methodology should be chosen in developing this system.

Facts and Findings:

Facts and findings establishes what the existing system does and what the

problems are, and leads to a definition of a set of options from which users may

choose their required system (Yeats and Wakefield, 2004a).This section will be

discussing about the domain of this project, the existing system and finally the

other techniques that applicable to be used while developing this project. It focused

on the how to design and develop the project systematically according to the

requirement of minimize the functional of conventional project. In the other


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situation, these will be describing any element or method which is useful to be

used for the purpose of searching and gathered useful information in developing

this project.

Domain:

Currently, electric powered bicycle that was studied for this project only

uses a battery to get the electric powered supply by recharge it using conventional

way. Electric powered bicycle only depends on power that charge in battery to

make it functions unless using the manual way to move it. The project is wanted to

change the way a battery charge to get the electric power and generate electricity to

move the bicycle with optimum energy.

Solar Power:

Solar cells (really called photovoltaic or photoelectric cells) that convert

light directly into electricity, bypassing thermodynamic cycles and mechanical

generators. PV stands for photo (light) and voltaic (electricity), whereby sunlight

photons free electrons from common silicon. A photovoltaic module is composed

of individual PV cells.

This crystalline-silicon module has an aluminum frame and glass on the

front. In the field of photovoltaic, a photovoltaic module is a packaged

interconnected assembly of photovoltaic cells, also known as solar cells. An

installation of photovoltaic modules or panels is known as a photovoltaic array or a

solar panel. A photovoltaic installation typically includes an array of photovoltaic

modules or panels, an inverter, batteries (for off grid) and interconnection wiring.

Solar energy is the utilization of the radiation energy from the sun.


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Solar power is used interchangeably with solar energy but refers more

specifically to the conversion of sunlight into electricity by photovoltaic and

concentrating solar thermal devices, or by one of several experimental technologies

such as thermoelectric converters, solar chimneys and solar ponds.

Sunlight is composed of photons, or particles of solar energy. These photons

contain various amounts of energy corresponding to the different wavelengths of

the solar spectrum.

When photons strike a photovoltaic cell, they may be reflected, pass right

through, or be absorbed. Only the absorbed photons provide energy to generate

electricity. When enough sunlight (energy) is absorbed by the material (a

semiconductor), electrons are dislodged from the material's atoms. Special

treatment of the material surface during manufacturing makes the front surface of

the cell more receptive to free electrons, so the electrons naturally migrate to the

surface.

When the electrons leave their position, holes are formed. When many electrons,

each carrying a negative charge, travel toward the front surface of the cell, the

resulting imbalance of charge between the cell's front and back surfaces creates a

voltage potential like the negative and positive terminals of a battery. When the

two surfaces are connected through an external load, electricity flows.

Electric Powered Bicycle:

An electric powered bicycle carries batteries or fuel cells that deliver electric

power to a motor that is coupled to either wheel. In most electric bicycles the rider

can choose to use muscle power to deliver all, part, or none of the propulsion

power required to maintain his or her adopted travel speed. Some models even


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sense your pedal pressure and command the motor to deliver more power

whenever you pedal hard.

Many electric powered bicycles are specifically design and build for travel.

Average travel speed, when compared to pedaled-only bicycles, can be increased

by 8 to 10km/h (5 to 6 mph) above the speed an average person could travel by

pedaling.

Previous Project:

Early 2001, David Clay was built a solar-electric bicycle. On this solar and

human powered rig, he rode from San Francisco, California, to Carbondale,

Colorado, arriving just in time to start a summer of classes at Solar Energy

International. In the summer of 2001, he went to China, and continued solar

cycling around the world. [15]

The trip was also the ultimate test for developing the solar cycle. He realized that

the bicycle needed a stronger PV mount after 30 miles traveling. Next, brakes

needed for the trailer after 100 miles and after 1,000 miles the trailer needed with a

spoke wheels. After 1,500 miles, powerful motor need to cover the performance of

bicycle that remains constantly. Performance of the bicycle is produce by a 24V

DC system. 4 to 5 A can be produce in full sun by the array of four Solar ex MSX

Lite modules. His trailer weighs 190 pounds (86kg) empty, and he pulled an

additional 85 to 100 pounds (3945 kg) of gear. He can cruise on the flat ground at

18 mph (29kph) without pedaling, with the motor drawing 13 amps. He then tested

the range of the bike on flat ground, with an unloaded trailer and a 150 pound (68

kg) rider, from full battery to empty battery (100% SOC to 20% SOC). It can

cruise in range of 25 to 30 miles (4050 km) without pedaling and sunshine. The

range is increase to 35 to 40 miles (5565 km) when it cruises with a pedaling and

sunshine. When pedaling, the riders fitness level becomes the only limit.


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Functions of Solar Panel:

The solar cells is divided in to p-type and n-type layers, the top layer which

is exposed to sunlight acts as a p-type layer and the bottom layer which is not

exposed to sunlight acts as a n-type layer.

The two layers are fused together the fused are is known as the junction.

Fusing of two layers is known as the semi conductors. The function of the solar

cell is as similar to a semi conductor. The positive terminal, which is exposed to

sunlight, is p type and the negative terminal is n type. This is known as forward

bias. Holes in P layer are repelled by the positive voltage and the electrons in the

n-layer are repelled by the negative voltage applied. Therefore the holes and

electrons moves towards the junction. Near the junction electron-hole combination

takes place.

The electron is liberated from the p-region and enters the terminal. The

process continues. Thus a large number of electrons will be flowing from negative

to positive terminal. Thus a current is flowing through the junction.

The maximum efficiency of 14% is obtained at a temperature of 28 degrees.

PHOTO VOLATIC EFFECT:

Photo voltaic effect is defined as the generation of an electromotive force as

a result of absorption of the ionizing radiation.


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It is the generation of an electric potential when absorbed radiation ionizes

atoms in the vicinity of an electrical potential battery (P-N junction). If the

radiation level is sufficiently separated electron hole pairs (EHP) are created in

turn crated an emf capable of causing a current flow through an electrical load.

The incident photon energy must equal or exceed the valance to conduction band

gap in order to produce electron hole pairs. In figure, shown how photon of proper

wave length creates EHP. These carries in turn migrates to the respective ohmic

contact in the n-layer, simultaneously the hole created by photon-electron energy

transfer migrates towards the p-layer. A current flow is induced

Photo voltaic effect:

.


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SILICON PHOTO VOLATIC CELL:

Solar cell modules:

In actual usage, solar cells are interconnected in a certain series and parallel

combinations to form modules. These modules are hermetically sealed for

production against corrosion, moisture, pollution and weathering combination of

suitable modules constitutes on array. One square meter of fixed array kept facing

south yields nearly 0.5 kWh of electrical energy on a normal sunny day if the

orientation of the array is adjusted face the suns ray a anytime, the output can

increase by 30% solar PV system can produce on output only if sunlight is present.

If it is required to be used during non-sunshine hours suitable system of storage

batteries will be required.


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There may be tracking arrays or modules or fixed arrays. A tracking array is

defined as one, which is always kept mechanically perpendicular to the sun array

line so that all times it intercepts the maximum insulation. Such arrays must be

physically movable by a suitable prime mover and are generally, considerably

more complex than fixed arrays. So we use fixed arrays which usually oriented

easy west and tilled up angle approximately equal to the latitude of the site. We

kept that 11 degree south facing latitude angle fixed arrays are mechanically

simple than tracking arrays. Thus array designs fall into two board classes and

thus use design as that of flat plate.

Flat plate arrays:

Where in solar cells are attached with a suitable adhesive to some kind to of

substrate structure usually semi rigid to prevent cells being cracked.

This technology springs from the space related photo-voltaic technology,

and, may such arrays have been built in various power sizes.

Concentrating arrays:

Where in suitable optics example Fresnel lenses, parabolic mirrors, and

compound parabolic concentrators (CPC) and others are combined with photo

voltaic cells in an array fusion. This technology is relatively new to photo voltaic

in terms of hardware development, and comparatively fewer such arrays have

actually been built.


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Solar cell connecting arrangement:

Cell may be connected in parallel to achieve the desired voltage. The

optimum operating voltage of a photo voltaic cell is generally about 0.45 V at

normal temperatures, and the current in full sunlight may be taken 0.270

amperes/sq.mm.

If the exposed area of the cell is 40 sq cm (6.2Sq.in) or 40*10^4 sq m., the

current and power are decreased or increased proportionately. By combining

number of solar cells in series that is in a string, the voltage is increased but the

current in unchanged. In this case, of one cell get damaged then the whole string

would become inoperative, similarly by combining number of solar cells in

parallel, the current is increased but the voltage is unchanged, in this change one

cell get damaged than it does not affect the other cell in the string.

To get a voltage of 0 to 6 V we require 12 cells to be connected in series so

that we connected 12 cells in series to a required voltage.

Construction:

The construction of the photo voltaic cell is also known as the barrier layer

or rectified cell as shown. It consists of a base plate made of either steel or

aluminum and carries a layer of metallic selenium, which is light sensitive.

An Electrically conducting layer of cadmium oxide is applied by sputtering

over the selenium layer.


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The layer is sufficiently thin to allow light to reach the silinium and is

electrically continuous as it acts as the negative pole. The negative contact is

formed of a strip of woods metal sprayed on to the edge of the top surface. The

base plate forms the positive contact. A transparent vanish protects the front

surface of the cell.

When light falls on the upper surface of the selenium, electrons are released

from the surface, which maintained a flow of current through the external circuit

connected between the positive and negative contacts.

In the current output of a photocell should be proportional to the

illumination, which is achieved by keeping the external resistance at a low value.

Also if greater accuracy is required then illumination should not be allowed to

exceed 25 lumens/feet^2. The smaller the size of the cell, of course compatible

with obtaining sufficient current to be properly measured the better a linear relation

is obtained between current and illumination. This because, for

Such a cell, the resistance of the electrically conducting film is at minimum, Also,

since the current is small, the voltage drop due to the circuit resistance will be kept

low.

Limitation of the photocell is that if the light is incident at the angels of 60

degree of above the lacquer tends to reflect a significant an amount of light which,

therefore, does not reach the selenium layer.

Thus the current is less that what it should be according to cosine lay of

illumination. Using a matt lacquer can make some compensation for this. A better

method is to omit the lacquer and cove the cell with a hemispherical dome of

transparent plastic. The equivalent circuit of a photo-voltaic is shown. Here


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E is a perfect photo-voltaic generator, which produces a current proportional to the

illumination.

Types of Solar cells:

Apart from the difference in the nature of the semiconductor used, the

following different cell configuration had been used:

1.

p-n homo junction2. p-n hetro junction3. Scotty barrier4. Homo junction hetro structure5. MIS (metal insulator-semi conductor cell)6. SIS (semi-conductor-insulator cell)

Battery:

In isolated systems away form the grid, batteries are used for storage of

excess solar energy converted into electrical energy. The only exceptions are

isolated sunshine load such as irrigation pumps or drinking water supplies for

storage. In fact for small units with output less than one kilowatt. Batteries seem

to be the only technically and economically available storage means. Since both

the photo voltaic system and batteries are high in capital costs, it is necessary that


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the overall system be optimized with respect to available energy and local demand

pattern. To be economically attractive the storage of solar electricity requires a

battery with a particular combination of properties:

1. Low cost2. Long life3. High reliability4. High overall efficiency5. Low discharge6. Minimum maintenance

a. Ampere hour efficiencyb. Watt hour efficiency

We use lead acid battery for storing the electrical energy from the solar panel for

lighting the street and so about the lead acid cells are explained below.


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Lead Acid Wet Cell:

Where high values of load current are necessary, the lead acid cell is the type

most commonly used, the electrolyte is a dilute solution of sulfuric acid (H2SO4).

The application of battery power to start the engine in an automobile, for example

the load current to the starter motor is typically 200 to 400 A. One cell has a

nominal output of 2.1 V, but lead-acid cells are often used in a series combination

of three for a 6 V battery and six for a 12 V battery.

The Lead Acid cell type is a secondary cell or storage cell, which can be

recharged. The charge and discharge cycle can be repeated may times to restore

the output voltage, as long as the cell is in good physical condition, however, heat

with excessive charge and discharge currents shortens the useful life to about 3 to 5

years for an automobile battery. Of the different types of secondary cells, the lead-

acid type has the highest output voltage, which allows fewer cells for a specified

battery.


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Automobile batteries are usually shipped dry from the manufacturer. The

electrode is put in at the time of installation, and then the battery is charged to from

the plates. With maintenance-free batteries, little are sealed, except for a pressure

vent, without provision for adding water.

The construction parts of battery are shown in fig.

Chemical Action:

Sulfuric acid is a combination of hydrogen and sulfate ions. When the cell

discharges, lead peroxide from the positive electrode combines with hydrogen ions

to form water and with sulfate ions to form lead sulfate. Combining lead on the

negative plate with sulfate ions also produces the sulfate. Therefore, the net result


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of discharge is to produce more water, which dilutes the electrolyte, and to form

lead sulfate on the plates.

As the discharge continues, the sulfate fills the pores of the grids, retarding

circulation of acid in the active material. Lead sulfate is the powder often seen on

the outside terminals of old batteries. When the combination of weak electrolyte

and sulfating on the plate lowers the output of the batter, charging is necessary.

On charge, the external D.C. source reverses the current in the battery. The

reversed direction of ions flows in the electrolyte result in a reversal of the

chemical reactions. Now the lead sulfates on the positive plate reactive with the

water and sulfate ions to produce lead peroxide and sulfuric acid. This action re-

forms the positive plates and makes the electrolyte stronger by adding sulfuric

acid.

CHEMICAL REACTION IN BATTERIES:


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At the same time, charging enables the lead sulfate on the negative plate to react

with hydrogen ions, this also forms sulfuric acid while reforming lead on the

negative plate to react with hydrogen, this also forms current can restore the cell to

full output, with lead peroxide on the positive plates, spongy lead on the negative

plate, and the required concentration of sulfuring acid in the electrolyte. The

chemical equation for the lead-acid cell is

Charge

Pb + Pbo2 + 2 H2So4 2PbSo4 + 2 H2O

Discharge


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On discharge, the Pb and Pbo2 combine with the So4 ions at the left side of

the equation to form lead sulfate (PbSo4) and water (H2O) at the right side of the

equation.

One battery consists of 6 cells, each have an output voltage of 2.1V, which

are connected in series to get a voltage of 12 V and the same 12V battery is

connected in series to get a 24 V battery. They are placed in the water proof iron

casing box.

Charging for lead Acid batteries:

Always use extreme caution when handling batteries and electrolyte. Wear

gloves, goggles and old clothes. Battery acid will burn skin and eyes and

destroy cotton and wool clothing.

The quickest way of ruin lead-acid batteries is to discharge them deeply andleave them stand dead for an extended change in the positive plates of the

battery. They change from lead oxide when charge out lead sulfate when

discharged. If they remain in the lead sulfate state for few days, some part of the

plate does not returns to lead oxide when the battery is recharged. If the battery

remains discharge longer, a greater amount of the positive plate will remain lead

sulfate. The parts of the plates that become sulfate no longer store energy.

Batteries that are deeply discharged, then charged partially on a regular basis can

fail in less than one year.


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Check your batteries on a regular basis to be sure they are getting

charged. Use a hydrometer to check the specific gravity of your lead acid

batteries. If batteries are cycled very deeply and then recharged quickly, the

specific gravity reading will be lower than it should because the electrolyte at the

top of the battery may not have mixed with the charged electrolyte.

Check the electrolyte level in the wet-cell batteries at the least four times a

year and top each cell of with distilled water. So not add water to discharged

batteries. Electrolyte is absorbed when batteries are much discharged. If you add

water at this time, and then recharge the battery, electrolyte will over flow and

make a mesh.

Keep the top of your batteries clean and check that cables are tight. Do not

tighten or remove cables while charging or discharging. Any spark around

batteries can cause a hydrogen explosion inside, and ruin one of the cells, and you.

On charge, with reverse current through the electrolyte, the chemical action is

reversed. Then the Pb ions from the lead sulfate on the right side of the equation

re-form the lead and lead peroxide electrodes. Also the So4 ions combine with H2

ions from the water to produce more sulfuric acid at the left side of the equation.

3.5. MICROCONTROLLER:

3.5.1. IC 89C51

DESCRIPTION:

IC89C51 will works on 5 Volts. The 89C51RX+ devices contain a non-

volatile FLASH program memory (up to 64 k bytes in the 89C51RD+) that is both

parallel programmable and Serial In-System Programmable. In-System

Programming allows devices to alter their own program memory, in the actual end


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product, under software control. This opens up a range of applications that can

include the ability to field update the application firmware.

A default serial loader (boot loader) program in ROM allows In-System

serial programming of the FLASH memory without the need for a loader in the

FLASH code. User programs may erase and reprogram the FLASH memory at will

through the use of standard routines contained in ROM.

These devices are Single-Chip 8-Bit Microcontrollers manufactured in

advanced CMOS process and are derivatives of the 80C51 Microcontroller family.

All the devices have the same instruction set as the 80C51. See P89C51RX2 data

sheet for devices which do not require a 12 V programming voltage. The devices

also have four 8-bit I/O ports, three 16-bit timer/event counters, a multi-source,

four-priority-level, nested interrupt structure, an enhanced UART and on-chip

oscillator and timing circuits.

For systems that require extra memory capability up to 64 k bytes, each can

be expanded using standard TTL-compatible memories and logic. The added

features of the P89C51RX+ Family makes those even more powerful

Microcontrollers for applications that require pulse width modulation, high-speed

I/O and up/down counting capabilities such as motor control.


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