2. Definition of
Terms
Electrolyte - is a chemical that allows an
electrical charge to pass between the two
terminals.
Anode - where an oxidation reaction occurs.
Cathode- it is said to be the electrode where
reduction occurs.
4. Introduction to
Batteries
Battery
A battery is a device that converts chemical
energy to electrical energy. A batteryâs
chemical reactions involve the flow of
electrons from one material (electrode) to
another via an external circuit. The flow of
electrons generates an electric current, which
can be used to perform work.
5. Introduction to
Batteries
What Is Battery Electrolyte?
The battery electrolyte is a solution inside
batteries. Depending on the type of battery, it
can be a liquid or paste-like substance. However,
no matter the type of battery, the electrolyte
serves the same purpose: it transports positively
charged ions between the cathode and anode
terminals.
Electrolyte serves as catalyst to make a battery
conductive by promoting the movement of ions
from the cathode to the anode on charge and
in reverse on discharge.
6. Introduction to
Batteries
How Does Battery Electrolyte Work?
A battery has three major components â the
cathode, the anode, and an electrolyte that
separates these two terminals. The electrolyte is
a chemical that allows an electrical charge to
pass between the two terminals. The electrolyte
puts the chemicals required for the reaction in
contact with the anode and cathode, therefore
converting stored energy into usable electrical
energy. This reaction provides power to the
connected device, whether itâs a light, a vacuum,
or an electric vehicle.
8. Introduction to
Batteries
Electrodes
The electrode is the place where electron transfer
occurs.
An electrode is classified as either a cathode or
an anode depending on the type of chemical
reaction that occurs. If an oxidation reaction
occurs at an electrode (oxidation being the loss of
electrons), then the electrode is classified as an
anode. If a reduction reaction occurs at an
electrode (reduction being the gain of electrons),
then the electrode is classified as a cathode.
9. How Batteries
Work?
Redox Reaction
Reactions in which electrons are transferred are called
oxidation-reduction (or "redox") reactions. There are
two parts to these changes: one atom must lose
electrons and another atom must gain them. These
two parts are described by the terms "oxidation" and
"reduction".
10. How Batteries
Work?
Oxidation
Originally, a substance was said to be oxidized when it
reacted with oxygen. Today, the word "oxidized" is still
used for those situations, but now we have a much
broader second meaning for these words. Today, the
broader sense of the word oxidation is defined as
losing electrons. When a substance loses electrons, its
charge will increase. This may feel a bit backwards,
but remember that electrons are negative. If an atom
loses electrons, it is losing negative particlesâso its
charge will increase.
11. How Batteries
Work?
Reduction
When an atom or an ion gains electrons, the charge
on the particle goes down. For example, if a sulfur
atom whose charge is zero (0)(0) gains two electrons,
its charge becomes (â2).the charge on the particle is
reduced by the gain of electrons. Remember that
electrons have a negative charge, so gaining electrons
will result in the charge decreasing. The
word reduction is defined to mean gaining electrons
and the reduction of charge.
14. Types of Cells
2 Types of Battery Cells
-Primary Cells â (Non-rechargeable) Once the cell
gives up all its energy, the chemical cannot react
again.
-Secondary Cells - (Rechargeable) Once the cell gives
up all its energy, the chemical reaction that causes it
to lose energy can be reversed by a charger, giving it
more energy to use in circuits.
15. Primary Cells
âą -Primary cells have high density and get
discharged slowly. Since there is no fluid inside
these cells they are also known as dry cells. The
internal resistance is high and the chemical
reaction is irreversible. Its initial cost is cheap and
also primary cells are easy to use.
-Chemical energy is converted to electrical energy,
but electrical energy cannot be converted back
into chemical energy.
16. Secondary Cells
âą -Secondary cells have low energy density
and are made of molten salts and wet cells.
The internal resistance is low and the
chemical reaction is reversible. Its initial cost
is high and is a little complicated to use
when compared to the primary cell.
-Chemical energy is converted to electrical
energy, and electrical energy is converted
back into chemical energy.
17.
18.
19. How Batteries
Work?
Battery Internal Resistance
The internal resistance (IR) of a battery is defined as the opposition to
the flow of current within the battery.
There are two basic components that impact the internal resistance of a
battery; they are electronic resistance and ionic resistance. The
electronic resistance plus the ionic resistance will be referred to as the
total effective resistance.
20. How Batteries
Work?
Basic component that impact the
internal resistance
Electronic resistance - The electronic resistance encompasses the
resistivity of the actual materials such as the metal covers and internal
components; as well as, how well these materials make contact with
each other.
Ionic resistance - is the resistance to current flow within the battery
due to various electrochemical factors such as, electrolyte conductivity,
ion mobility and electrode surface area.
21. Effects of
internal battery
resistance.
âą A battery with low internal
resistance delivers high
current on demand. High
resistance causes the battery
to heat up and the voltage to
drop. The equipment cuts off,
leaving energy behind.
22. Batteries
Common Battery Sizes
AA Batteries - Also known as âdouble Aâ, AA batteries are by far the
most popular battery size. Used in a multitude of applications, these
batteries can be purchased almost anywhere.
AAA Batteries - Also known as âtriple Aâ, AAA batteries are the second
most popular kind of battery. They are used for small toys,
thermometers, and calculators.
AAAA Batteries - These small but powerful batteries are often used in
LED penlights and laser pointers. They are also frequently used in small
devices such as glucose meters, hearing aid remote controls, and
powered computer styluses.
C Batteries - Many automatic hand sanitizer dispensers require the use
of these 1.5V batteries. Perfect for heavy-duty applications where
batteries require frequent use, you can be sure that your device is
operating with safe, reliable power. These batteries are also frequently
used in restrooms that utilize battery powered flush sensors.
23. Batteries
Common Battery Sizes
D Batteries - Powering most automatic paper towel dispensers, D
batteries are essential. These large, bulky batteries provide hours of use
and power a variety of commercial, heavy-use devices, like hands-free
sensor faucets, air freshener systems, and soap dispensers.
9V Batteries - Generally known for its rectangular shape, the 9-Volt
battery is used in devices that require high voltage and lots of power.
CR123A Batteries - Packed with power, this battery is frequently used
for tactical equipment, wireless security, and home automation.
23A Batteries - This small battery is commonly used in small devices
such as garage door openers, specialized medical devices, watches, or
remotes.
CR2032 Batteries - At 3 volts, the CR2032 battery is commonly used in
watches, calculators, toys, and different medical devices. These batteries
provide long-lasting, reliable power and have a very high weight-to-
power ratio.
24. Batteries
Common Battery Sizes
12 Volt Battery - Large, block-shaped, and heavy, this battery provides
hundreds of amps of electrical current and is commonly used in cars and
other industrial equipment. Compared to some of the bigger voltage
batteries, it might not make sense that a car is able to function with only
12 volts while other heavy equipment requires much more than just 12
volts. This is because heavy equipment and cordless power tools all
require a charge after their energy has been depleted. Cars use an
alternator which acts as a generator to keep the car's battery powered,
eliminating the need for an external charger.