How Batteries Work!Intro to Ag

Spring 2009

Batteries!- A Battery is a device that stores

chemical energy and converts into electrical form.

- They are an integral part of modern life. Almost everything, from cell phones, beepers, laptops, to medical instruments that restart the human heart get their energy from batteries.

When w

as the first battery invented?

In 1800, Alessandro Volta invented the first modern electric battery. Volta demonstrated that an electrical current is generated when metals and chemicals come into contact.

What are the main components of a battery?

Battery consists of: 1.Electrodes-where the electrochemical reaction

takes place. 2.Electrolyte-medium for the movement of ions

within the cell and actually carry the ionic current inside the battery. This is usually a gel.

3. Separator-a non-woven, fibrous fabric which separates the electrodes and holds the electrolyte between electrodes.

4.Each cell has a positive electrode (cathode), and a negative electrode (anode) .

Batteries!

Biggest Battery -ABB, the global power and automation technology group, built the world’s largest battery energy storage system in Fairbanks Alaska. The battery is a high performance nickel-cadmium storage battery made up of 13,760 energy cells. Each cell measures 16 in. by 21 in. This NiCad battery is approximately 21,520 square feet in size. It provides 40 megawatts of power -enough electricity for 12,000 people -for up to seven minutes.

Smallest Battery-The smallest battery in the world measures 2.9 mm in diameter and 13 mm in length (about the size of a pencil tip). The battery is made of a polysiloxanepolymer, a material that has the highest conductivity . Recharging the battery is done wirelessly by an external electrical field .It is designed to stimulate damaged nerves and muscles inside the human body.

Types of batteries

Primary batteries irreversibly transform chemical energy to electrical energy. Once the initial supply of reactants is exhausted, energy cannot be readily restored to the battery by electrical means.

Secondary(Rechargeable) batteries can have the chemical reactions reversed by supplying electrical energy to the cell, restoring their original composition .

Smart Battery -Intelligent Batteries which convey the charger which algorithm to apply, provide protection from overcharging, under-discharging and short-circuiting. - Smart Batteries are used in MP3 players, Laptops , Cell Phones, DVD players, and other electronic devices.

Rechargeable Batteries

chemical reaction that occurs is reversed while charging.

When connected to an appropriate charger, cells convert electrical energy back into potential chemical energy.

The process is repeated every time the cell is discharged and recharged.

Why Rechargeable Batteries ?

Purchasing rechargeable batteries saves money.

protects the environment. conserves resources. They can be re-used many times,

reducing operating costs.

When NOT to Use Rechargeable Batteries:

They should NOT be used for emergency equipment

Because they lose up to 1% of their power capacity per day.

They are not good choices for the following:

Emergency equipment (flashlights, radios, emergency medical devices, etc…).

Battery Failures

Battery failure

Battery abuse happens in a variety of ways which includes altitude change, shock, external short circuit, impact, overcharge, forced discharge.

Battery misuse is unintentional consumer misuse of a battery.

Improperly selected hardware

Uncontrolled Manufacturing Processes –including badly run production facilities which lead to cell short circuits, leaks, unreliable connections, sealing quality, mechanical weakness and contamination.

Measuring and Calculating Electricity:

Amperes (Amps): the rate of electrical flow

Watts: a measure of electrical power Kilowatt: equal to 1,000 watts Kilowatt Hour (KWH): the measure or

electrical energy used for one hour of time.

Formulas Amps x volts = watts Watts/1,000 = KWH Watts x hrs x days= total watts used

How much would it cost to watch TV for on month if you averaged watching 3 hours a day? The TV is rated at 225 watts and electricity costs $.08/kwh.