Electrical Fundamentals - Introduction to Batteries
A. Bhatia, B.E.
Batteries are the power source for millions of consumer, business, medical, military, and industrial appliances worldwide. Since different devices operate at different voltages and power levels, there is not a single battery that suits each application. There are many different types of batteries available in market that provides diverse capacity ratings, voltage levels and the storage capacities. This course will discuss the characteristics and application of different types of batteries in detail.
This 3-hr course
material is based entirely on Naval Education and Training Materials (NAVEDTRA
14173), Electricity and Electronic Training Series; Module-1 "Introduction
to matter, energy and direct current" and covers Chapter 2.
This course includes
a multiple-choice quiz at the end, which is designed to enhance the understanding
of course materials.
At the conclusion of this course, the student will be able to:
This course is aimed at students, professional engineers, service technicians, energy auditors, operational & maintenance personnel, facility engineers and general audience.
A battery is a device that generates an electrical current by chemical reaction. Batteries operate on a simple theory: two dissimilar metals in contact with an electrolyte will produce a flow of electrons (electricity) when all elements are in contact with each other.
Rechargeable batteries used in critical backup power applications varying a lot in chemistry, construction and size. Designs vary according to the usage requirements, such as power draw, form factor, storage capacities and operating temperatures. To fit in a specific application:
In this course, you
are required to study Naval Education and Training Materials (NAVEDTRA 14173),
Electricity and Electronic Training Series; Module-1 "Introduction to Matter,
Energy and Direct Current" Chapter 2:
Please click on the above underlined hypertexts to view, download or print the documents for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader.
A battery is a
portable, backup power device that generates an electrical current by chemical
reaction. There are many different types of batteries but they all store energy
as chemical potential - i.e. two chemicals react in a solution to create a circuit.
There are four basic elements that make up a battery: the anode, the cathode, the electrolyte and the separator. The anode is the negative electrode - or area of the battery - where electrons are lost (oxidation is occurring) and where positive ions are produced. The cathode is the positive electrode where electrons are gained (reduction is occurring) and where negative ions are produced. The electrolyte acts as a bridge between the electrodes, allowing the positive and negative ions to flow back and forth. The separator provides a reservoir for the electrolyte and electrically isolates the anode and the cathode, preventing the chemical reaction from occurring in one fell swoop.
The capacity of a battery is determined by the amount of chemical energy stored inside its housing. It determines - for a given current of a given device - the service life of the battery. There are broadly two different types of batteries: primary and secondary.
Primary batteries cannot be recharged or "brought back to life" once they have used up their power. Examples of primary batteries include alkaline batteries that are commonly used in flashlights, portable radios and miscellaneous consumer electronics devices.
Secondary batteries, also known as storage batteries, are capable of being recharged and reused up to 500 times (charge/discharge cycles). Nickel Cadmium, Nickel-Metal Hydride and Li-Ion batteries (used in many portable electronic devices such as two-way radios and bar code scanners) are examples of this type (belong to this category). The most common type of secondary cell is the "lead-acid" type used to start motor car engines. Taken to the extreme lead-acid batteries can produce a very high output for a short duration. These batteries are the least expensive but have a limited life and store less energy per pound than other types.