BATTERY BASICS The Lemon Cell Battery Vex 1

  • Slides: 16
Download presentation
BATTERY BASICS The Lemon Cell (Battery) Vex 1. 0 © 2005 Carnegie Mellon Robotics

BATTERY BASICS The Lemon Cell (Battery) Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

BATTERY BASICS INTRODUCTION • 1800 – Alessandro Volta • • discovered the chemical battery

BATTERY BASICS INTRODUCTION • 1800 – Alessandro Volta • • discovered the chemical battery by creating a portable electricity source known as a “Voltaic Pile”. A Voltaic Pile is a device using pieces of silver and zinc separated by moist cloth soaked in an electrolyte (in Volta’s case, sea water) solution. Humphry Davy later proved that the electricity from voltaic piles was caused by the chemical reaction, and not the different metals, as first assumed. Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

BATTERY BASICS Voltaic Pile • In the lemon experiment, the • lemon juice allows

BATTERY BASICS Voltaic Pile • In the lemon experiment, the • lemon juice allows the metal plates to gain or lose electrons. Then, those electrons travel over to the other plate (via the electrolyte solution, lemon juice), forming a redox reaction. The electrolyte is electrically the same on both sides, but the reaction creates a different electrical potential on the two different plates, so connecting them shows a voltage difference. Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Battery Material List • Figure 1: Alligator clips with wires attached. •

The Lemon Battery Material List • Figure 1: Alligator clips with wires attached. • Figure 2: Copper and Zinc metal strips (Galvanized Sheet Steel will work fine for the Zinc strips) Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Material List • Figure 3: A sharp knife and extra

The Lemon Cell (Battery) Material List • Figure 3: A sharp knife and extra fine steel wool or Scott’s Brite • Figure 4: Galvanometer Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Material List • Figure 5: Multi-Meter • Figure 6: LED’s

The Lemon Cell (Battery) Material List • Figure 5: Multi-Meter • Figure 6: LED’s (1. 8 volt) Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Material List • Figure 7: Thermometer with LCD Digital Display

The Lemon Cell (Battery) Material List • Figure 7: Thermometer with LCD Digital Display • Figure 8: DC Motors and computer fans. Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Material List • Figure 9: Lemons • Figure 10: Egg

The Lemon Cell (Battery) Material List • Figure 9: Lemons • Figure 10: Egg Crate to hold lemons Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Assembly Procedures • Step 1: Obtain a Copper and Zinc

The Lemon Cell (Battery) Assembly Procedures • Step 1: Obtain a Copper and Zinc Strip and clean both sides with steel wool or Scott’s Brite • Step 2: Obtain a Lemon, and roll it on the bench top to break internal fibers in the Lemon. Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Assembly Procedures • Step 3: Using a sharp • •

The Lemon Cell (Battery) Assembly Procedures • Step 3: Using a sharp • • knife, make two slits on one end of the lemon, as SAFETY shown. Be careful not to cut yourself! Step 4: Insert a copper strip into one of the slits and a zinc strip into the other, as shown. Use an egg crate to hold the lemons. Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Experiment Procedures • Step 1: Connect the alligator clips with

The Lemon Cell (Battery) Experiment Procedures • Step 1: Connect the alligator clips with wires to the metal strips, as shown. • Step 2: Connect the wires to the galvanometer on the Go terminal. Note that the needle is pegged. Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Experiment Procedures • Step 3: Connect the • lemon to

The Lemon Cell (Battery) Experiment Procedures • Step 3: Connect the • lemon to the G 1 terminal of the galvanometer. The G 1 terminal has a resistor inline. What happened? Why? Step 4: Now connect the lemon to the multimeter with the range set at DCV 2. How much voltage is the lemon cell producing? Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Experiment Procedures • Step 5: Put 3 lemon • cells

The Lemon Cell (Battery) Experiment Procedures • Step 5: Put 3 lemon • cells in series. Why in series? Note copper is connected to zinc. Why? Connect as shown. Now we have a lemon battery. Why? Step 6: Connect this Lemon battery to the multi-meter that is set to DCV 20. Why DCV 20 and not DCV 2? How much voltage is the battery producing? Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) 1. 8 Volt LED Lemon Powered • Figure 1: LED

The Lemon Cell (Battery) 1. 8 Volt LED Lemon Powered • Figure 1: LED Off • Figure 2: LED On. Using 5 Lemons. What is the voltage of the Lemons? What is the amperage of the 5 Lemons? What is the minimum number of Lemons that will Power the LED? What is the voltage of the minimum number? What is the amperage? Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Powers 3 Volt Digital Electric Thermometer • Figure 1: Thermometer

The Lemon Cell (Battery) Powers 3 Volt Digital Electric Thermometer • Figure 1: Thermometer unplugged. What is the voltage of the 4 lemons? What is the amperage? • Figure 2: Thermometer on. What is the minimum number of lemons needed to power thermometer? What is the voltage and amperage of this minimum number? Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.

The Lemon Cell (Battery) Can the Lemons power a computer fan? • How many

The Lemon Cell (Battery) Can the Lemons power a computer fan? • How many lemons will be needed to power a 12 VDC computer fan? Will this be possible? Vex 1. 0 © 2005 Carnegie Mellon Robotics Academy Inc.