Design And Construction Of 12V And 24V Automatic Battery Charger With Full Charge Alarm

INTRODUCTION
Background of the Study
A battery charger is described as is a device that provides electricity to convert into stored chemical energy for storage in an electrochemical cell by running an electric current through it. [Zhang et al, 2013].
A battery charger consists of a rectifier circuit, power circuit, ripple monitoring, control circuit, regulator circuit.
A Battery charger comes in various designs and voltage. The choice of a particular charger depends largely on the size of battery.
The battery charge is built in such a way that it delivers a constant value of d.c current into the battery it is charging in the opposite direction from which current flows on the batteries during discharge one cannot successfully design a battery charge without a fundamental understanding of the accumulator because it also makes up the operation according to [Zhang et al, 2013].
This work is aimed at building a 12 and 24volt automatic battery charger with full charge alarm.

1.2 Problem Statement
There is nothing is as dangerous as when a battery was fully charged and the owner is not aware of the charging state. This study solve problems such as not knowing when it is fully charged which can cause the battery not to charged or to over-charge.

1.3 Hypothesis/Research Questions
H1: There is a significant relationship between charger and rechargeable battery.

1.4 Research Questions
What is the importance of battery charger?
Is there any disadvantage of using this type of battery charger?
What is the operating principle of a battery charger?

1.5 Aim and Objective of Study
The main aim of this work is to build an automatic battery charger of 12 and 24volt with full charge alarm. The objectives are:

• To build the device
• To know when a battery is charging or not
• To know the status of a battery thereby saving the battery from over-charge

1.6 Significance of Study
Carrying this work will go along way teaching students how battery charger is been made and the operation of battery charger. This study will also be of great benefit to all users of charger and rechargeable devices in that it will help them to understand how their battery is been charged and how chargers are operated.

1.7 Scope of Study
The scope of this work focuses on the building of a 12v and 24v battery charger that incorporated an alarm for fully charge alarm indicator. In this work, the selection of charging voltage and voltage monitoring alarm is done using switches.

1.8 Limitations of Study
This charger can only be used for 12 and 24v batteries. The final packaging of the device will compose of two LEDs which includes LED for power and charging output voltage.

1.9 Definitions of terms
Below are terms that are frequently used in this work and their definitions:
Battery: a container consisting of one or more cells, in which chemical energy is converted into electricity and used as a source of power.
Charger: a device for charging a battery or battery-powered equipment.
Capacitor: a charge storage device made up of two metallic plates separated by a dielectric, with equal but opposite charges. The AC impedance of a Capacitor is (1 / jWL) and acts as an open circuit in DC applications.
Circuit: a complete path that allows electrical current from one terminal of a voltage source to the other terminal.
Alternating (AC) Current: currents that have a harmonic time dependence.
Ampere (A): the unit of measurement for electrical current in coulombs per second.