11.1 Cells and Batteries(Page 437-444)

Learning Goals

• I can describe the components of electric circuits.

• I can explain how voltaic cells work.• I can explain how electrical cells are

classified.• I can contrast electric and hybrid vehicles

with regular, gas burning vehicles.

KEY CONCEPTS:

In a voltaic cell, chemical reactions involve two different metals or metals compounds (called electrodes), and a conducting solution or a paste (called an electrolyte).

• A battery is a connection of two or more cells.

A dry cell contains an electrolyte that is a paste, whereas a wet cell contains an electrolyte that is a liquid solution.

• A primary cell can be used only once, and then it is discarded, whereas a secondary cell can be recharged many times.

A fuel cell generates electricity using chemical reactions of fuel stored outside the cell.

A solar cell converts sunlight, a renewable energy source, into electrical energy.

Electric and Hybrid Vehicles• Regular gas-burning cars use fuel and release carbon

dioxide at all times, even when stuck in traffic• Electric cars charged by the power generated at oil

burning generating plants convert twice as much energy to making the cars move

• Hybrids save on fuel by converting braking energy into electrical energy which can later be used to move the car

• Hybrids and electric cars, waste less fuel and produce less CO2 than regular gas cars

Electric Circuits

• Electric circuit: a closed path along which electrons that are powered by an energy source can flow

Electrical Cell Terminology

• Electrical cell: a device that is used to generate electricity

• Terminal: the point at which a conductor comes to an end

• Battery: a connection of two or more cells• Electrode: one of two metal terminals in a cell or

battery• Electrolyte: a solution or paste that conducts

charge

Voltaic Cells• Voltaic cell: a source of energy that

generates an electric current by chemical reactions involving two different metals or metal compounds separated by a solution that is a conductor

• The solution is an electrolyte• Electrons flow from one electrode to the

other outside of the battery, while inside the battery the circuit is closed by the electrolyte's ions

Voltaic Cells• Video: How voltaic cells work

Voltaic Cells

Types of Cells

• Dry cell• Wet cell• Primary cell• Secondary cell• Fuel cell• Solar cell

Types of Cells and Examples of Each OneType of Cell Description Examples

Dry Cell A cell that contains an electrolyte that is a paste.

Zinc-carbon cellsAlkaline cells

Wet Cell A cell that contains an electrolyte that is a liquid.

Lead acid batteries

Type of Cell Description Examples

Primary Cell A cell that can be used only once.

Zinc-carbon cells

Secondary Cell A cell that can be recharged.

Nickel-metal hydride cells

Type of Cell Description Examples

Fuel Cell A cell that generates electricity through the chemical reactions of fuel that is stored outside the cell.

Hydrogen fuel cell

Solar Cell A cell that converts sunlight into electrical energy.

Solar panels

Practice

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