Design and Construction of 12v Battery Charger
Chapter One
Aims and Objective
The major aim and objective of this project is to design and construct a battery charger that can be use to charge any kind of 12v rechargeable batteries including alkaline, NiCad or lead acid batteries. With the lack of centralized power grids, car batteries have taken the place of one of the main energy sources available in developing countries. With this in mind, our objective will be to design a cheap, versatile and efficient lead acid car battery charger which will interest and appeal to the “cost-minded” customer. One of our main incentives in developing this project is for a low-cost charger (affordable) to integrate or combine with other device. After carrying out our project research on the targeted users, they have been able to devise a list of particular features that would be essential in the project, like designing battery charger to be universal. Using a standard AC power, ability to charge a typical 12 Volt lead-acid (automotive) battery. We used these requirements as guidelines to implementing our product as well as include additional features that we thought are important to the functionality.
CHAPTER TWO
LITERATURE REVIEW
History of Battery Invention And Development
Our history of batteries begins with the Baghdad battery. Why was a battery required 2000 years ago? In June, 1936, workers constructing a new railway near the city of Baghdad uncovered an ancient tomb. Relics in the tomb allowed archeologists to identify it as belonging to the Parthian Empire. The Parthians, although illiterate and nomadic were the dominating force in the Fertile Crescent area between 190 BC to 224 AD. It is known that in 129 BC they had acquired lands up to the banks of the Tigris River, near Baghdad. Among the relics found in the tomb was a clay jar or vase, sealed with pitch at its top opening. An iron rod protruded from the center, surrounded by a cylindrical tube made of wrapped copper sheet. The height of the jar was about 15 cm, and the copper tube was about 4 cm diameter by 12 cm in length. Tests of replicas, when filled with an acidic liquid such as vinegar, showed it could have produced between 1.5 and 2 volts between the iron and copper. It is suspected that this early battery, or more than one in series, may have been used to electroplate gold onto silver artifacts. A German archeologist, Dr. Wilhelm Konig, identified the clay pot as a possible battery in 1938. While its 2000-year old date would make it the first documented battery invention, there may have been even earlier technology at work. Dr. Konig also found Sumerian vases made of copper, but plated with silver, dating back to 2500 BC. No evidence of Sumerian batteries has been found to date.
principle of battery-powered telegraph discovered.
In 1747, Sir William Watson demonstrated in England that a current could be sent through a long wire, using the conduction through the earth as the other conductor of the circuit. Presumably the current was from an electrostatic discharge, such as from a Leyden jar charged with high voltage. People at that time knew how to generate electrostatic voltages by rubbing dissimilar materials such as glass and fur together. Then in 1753 a certain C.M. in Scotland devised a signaling machine that used an insulated wire for each letter of the alphabet. At the sending end an electrostatic charge was applied to the selected wire, and a pith ball jumped at the receiving end in response to the voltage.
Luigi Galvani Notices The Reaction Of Frog Legs To Voltage
Luigi Galvani (1786) was remarkably close to discovering the principle of the battery, but missed it. He thought the reaction was due to a property of the tissues. He used two dissimilar metals in contact with a moist substance to touch dissected frog legs. The resulting current made the muscles in the frog legs twitch. Luigi Galvani made many more important discoveries later, when the relationship between magnets and currents became known. The galvanometer is named for him. It is a moving coil set in a permanent magnetic field. Current flowing through the coil deflects it and an attached mirror, which reflects a beam of light. It was the first accurate electrical measuring instrument.
Details Of A Battery Published By Volta
1800 — Alessandro Volta publishes details of a battery: That battery was made by piling up layers of silver, paper or cloth soaked in salt, and zinc. Many triple layers were assembled into a tall pile, without paper or cloth between zinc and silver, until the desired voltage was reached. Even today the French word for battery is ‘pile’ (English pronunciation “peel”.) Volta also developed the concept of the electrochemical series, which ranks the potential produced when various metals are in contact with an electrolyte. How handy for us that he was well known for his publications and received recognition for this through the naming of the standard unit of electric potential as the volt. Otherwise, we would have to ask “How many galvans does your battery produce?” instead of asking “how many volts does your battery produce?”
CHAPTER THREE
DESIGN METHODOLOGY AND SYSTEM ANALYSIS
Design Methodology
The design approach to this project was realized through the implementation of its input subsystem, control unit and output subsystem. A computer aided design software known as Proteus ISIS Professional was used for the design and simulation of the battery charger paper design before the hardware was actualized using the block diagram methodology shown in figure 3.1 below.
This architectural design method is used in this project work to minimize cost and as well actualize the quoted system design specification. There are three key functions in battery charger methodology (Fig 3.2 circuit diagram), which involves getting the charge into the battery, optimizing the charging rate and knowing when to stop charging the battery.
CHAPTER FOUR
SYSTEM IMPLEMENTATION
HARDWARE DESIGN
The final hardware design of this project was done on a veroboard. The veroboard was inspected of wrong linkages in its line which may be a mistake from the producers. The holes of the board were checked to be through for passing the terminals of the components for soldering. An abrasive paper was used on the soldering section of the board for easy binding of the terminals on the board.
CHAPTER FIVE
SYSTEM TESTING
TESTING
After the design and implementation phase, the system built has to be tested for durability, efficiency, and effectiveness and also to ascertain if there is need to modify the design. The system was first assembled using a breadboard. All components were properly inserted into the breadboard from whence some tests were carried out at various stages. To ensure proper functioning of components’ expected data, the components were tested using a digital multimeter (DMM). Resistors were tested to ensure that they were within the tolerance value. Faulty resistors were discarded. The DC voltage regulator was also tested; the resulting output was 12.02v which is just a deviation of 0.20v from the expected result of 12.00v. The battery charger was tested to ensure that they were all working properly.
CHAPTER SIX
SUMMARY, RECOMMENDATIONS AND CONCLUSION
SUMMARY
This section of this project report forms the concluding part of the write up and takes a look at some of the problems encountered during the progressive job on the system and also brings in suggestions for further improvement and/or enhancement for the system design. The design and development of this project has really been challenging, as I have been faced with choices far beyond what I expected. But in the long run the result paid off. After the complete design of the system, the deviation between the expected result and the actual result was very close. The performance and efficiency was beyond expectation and from every ramification, the design of the project was a success.
During the course of the design of this system, there were series of problems, most of which where over come via share troubleshooting, in some cases some parts require redesigning and the software design also created a bit of a problem. One major setback of this project is the availability of components required to build the hardware of the system. In most cases I had to look through electrical catalogs to obtain replacements of some of the components which are not available in the market. After designing the paper design of the project, it was very difficult to find a firm/individual to help me on the simulation software for the design. This posed serious problem as it brought about delay in the design time and it was also costly, this also affected the overall cost of the system. The final packaging of the design was also another trouble, as this actually caused problems on the circuit board. Such problems include partial contact within the circuit board, between components and also with the wiring. This was actually one of the most challenging aspects of the circuit implementation phase. Due to this fact, there was a lot of soldering and de-soldering to ensure that the circuit was well implemented and seated.
RECOMMENDATIONS
Though this project is still a prototype, I recommend it to offices and institution of higher learning to use it for battery charging. No need of searching or visiting a battery charger electrician to refill your batteries when it runs down.
CONCLUSION
Going through the planning, flow process, design and software implementation the system had really been a tough one; but on the whole it has been a chance to show case a little bit of craftsmanship.
REFERENCES
- A Guide to Understanding Battery Specifications, MIT Electric Vehicle Team, December 2008
- http://en.wikipedia.org/wiki/Battery_eliminator
- Effects of AC Ripple Current on VRLA Battery Life”by Emerson Network Power
- Dave Etchells. “The Great Battery Shootout”.
- “AN913: Switch-Mode, Linear, and Pulse Charging Techniques for Li+ Battery in Mobile Phones and PDAs”. Maxim. 2001.
- “Lead–acid battery sulfation”. Archived from the originalon 2007-04-02.
- “”fast pulse battery charger” patent”. 2003.
- “Battery charger with current pulse regulation” patented 1981 United States Patent 4355275
- Pulse-charge battery charger” patented 1997 United States Patent 5633574
- http://www.dallas.net/~jvpoll/Battery/aaPictures.htmlPulse charger/desulfator circuit schematic
- The pulse power(tm) battery charging system”
- ^“Negative Pulse Charge, or “Burp” Charging: Fact or Fiction?”