# Connecting Batteries in Series

3.0 based on 28 ratings

#### Updated on Sep 30, 2013

##### Type

Physical Science, Electronics

5+

Easy

##### Cost

Minimal, mostly the cost of batteries for the display

##### Safety Issues

Minor risk of too much voltage/amperage, which can make the wires hot enough to melt. Soldering connectors makes the display easier but presents the possibility of burns. Taking a dry cell battery apart means exposure to the caustic electrolyte inside.

Common

##### Approximate Time

1-2 hours, depending on complexity of the display

### Objective

To demonstrate how battery packs work to bring higher voltage, higher amperage, or both.

### Materials

• Several batteries, to be connected in series, parallel, and series-parallel
• Battery holders, or wire and soldering equipment
• Voltmeter also capable of measuring amperage (Radio Shack)
• Optional – a disassembled battery to label the parts

### Introduction

A single battery cell produces low voltage and low amperage. Combining cells in series increases the voltage. Combining them in parallel increases the amperage. Even a 9-volt battery is a “battery pack.” This project will explore how battery cells can be connected in many different configurations to do almost anything needed, depending on the voltage and amperage needed.

### Photos

Students can show diagrams of practical series/parallel circuits. In addition, devices that use multiple batteries can be displayed to demonstrate how, for example, 4 batteries are used to power a device that requires 6-volts.

### Research Questions

• What is a battery cell?
• What is a series circuit?
• What is a parallel circuit?
• Is a 9-volt battery a battery cell, or a battery pack? How and why?
• What is the difference between DC and AC?

### Terms

• Volt: the standard measure of electric pressure
• Ampere: the standard measure of electric quantity
• Series: one after another, like strings tied together
• Parallel: in line, side-by-side, like railroad tracks

### Concepts

Electricity is the movement of electrons in a conductor. Voltage is the pressure, somewhat like the pounds per square inch of water flowing from a pipe. Amperage is the quantity of the electrons, somewhat like the number of gallons flowing from the pipe. Batteries generate electricity by a chemical reaction. They can be connected inline to provide greater voltage, in parallel to provide greater amperage, or in a combination to provide both greater voltage and greater amperage.

Connecting batteries in series involves creating a series circuit, which has the positive post connected to the negative post of another battery with each battery in line. Two 6-volt, 2 amp batteries connected this way will produce 12 volts, 2 amps.

A parallel circuit has the positive post connected to the positive post of another battery, and the negative post connected to the negative post. Two 6-volt, 2 amp batteries connected this way will produce 6 volts, 4 amps.

A series-parallel circuit combines both to produce whatever voltage and/or amperage is needed. For example, if 120 volts is needed, 20 6-volt batteries in series will provide the needed voltage. If each battery has a 1-amp capacity but 50 amps is required, 25 sets of those 20 batteries, the sets connected in parallel, will provide the end result of 120 volts at 50 amps.

### Experimental Procedure

1. Gather the materials.
2. Decide if you will use battery holders or solder.
3. Build a series circuit of batteries, and measure voltage and amperage.
4. Build a parallel circuit of batteries and measure voltage and amperage.
5. Build a battery pack to combine both and measure voltage and amperage.
6. Measure and record voltage and amperage of each.
7. Optional – disassemble a common battery to show the parts. (Adult supervision should be used because the electrolyte inside is caustic.)

### Bibliography

Gene B. Williams is a freelance writer with 54 published books and thousands of stories and articles. He has been a science teacher and assistant headmaster at a private school, then senior editor for three educational publishers. One of his newest projects is "Nicker Stories," a delightful and humorous collection of stories about a young boy and his sea dragon.