| RSS Web Feed for Renewable Energy UK | REUK Shop | Directory | Bookmark Site | About Us  

Lemon Battery



Lemon Battery

Make a battery from a lemon

education | general
Printer Friendly Version Print Article     

Measuring the voltage generated by a lemon battery

It is possible to make a simple battery from a lemon. This is a very simple experiment and requires no expensive or complex equipment. A basic battery consists of two different metals suspended in an acid solution. For our experiment a lemon (citric acid) or vinegar (acetic acid) works well. The lemon juice is the electrolyte through which electrons will travel from one metal to the other.

Electric Potential

All metals have something called electric potential which is basically a measure of how easily they give up electrons (or attract electrons if the value is below zero). For example calcium has a potential of +2.20 volts, whereas gold has a potential of -1.10 volts. Using two metals, the difference between potentials can be used to create a flow of electrons. For example the flow of electrons between calcium and gold equates to a potential difference of 3.30 volts (= +2.2 - -1.1). This would be an expensive battery - therefore look at the potential voltage of some common metals - Aluminium (+1.30), Zinc (+0.758), and copper (-0.345) then we see it is possible to make a cell of around 1 volt very cheaply.

Lemon Battery

Lemon cell (battery) made with aluminium and copper.
A good fresh and juicy lemon works best, but a potato or apple can easily be used. Cut a shallow slit in one side of the lemon and insert either a copper coin (sometimes coins thought to be copper are in fact not pure copper so use copper wire instead if necessary), and in the other side insert a galvanised nail (which is coated with zinc) or metal paperclip. The copper coin/wire is the +ve electrode of the cell, and the galvanised nail is the -ve electrode. The electrons will travel from the -ve electrode through the electrolyte to the +ve electrode - thereby creating an electric current. Below is an illustration of an aluminium-copper lemon cell.

Lemon battery made up of two lemon cells connected in series
If you measure the voltage across the lemon cell then it will be just under 1 volt - not enough to do anything useful. However if you connect a few of these lemon cells together in series (+ve to -ve, +ve to -ve, and so on as shown above) then a higher voltage battery can be built. Once the voltage is over 2-3 volts the battery of lemon cells can be used to light up (not very brightly) an LED. Four lemon cells connected in series will typically generate around 3.5 volts.

Lemon battery used to light up an LED

Vinegar Battery

An alternative to the lemon battery is to use empty film cannisters filled with vinegar, with a zinc nail and some copper wire dangled through holes in the lid into the liquid. Two of these can be wired in series and used to power a small LCD clock or calculator.

Article Last Modified: 15:13, 19th Aug 2008


Recommended Related Articles

People who read this article also enjoyed the following articles:

Make a Shunt Resistor
Make your own rough and ready shunt resistor
Article Last Modified: 12:52, 28th Feb 2007
electric circuit | education

How Do PV Solar Panels Work
Find out how photovoltaic solar cells generate electricity
Article Last Modified: 11:12, 4th Apr 2006
solar | education

Three Phase Basics
Get an understanding of three phase wiring in wind turbine alternators
Article Last Modified: 15:13, 19th Aug 2008
wind | electric circuit | websites

Bwired Energy Usage and Home Automation
Find out more about tracking energy usage and home automation
Article Last Modified: 10:35, 2nd Sep 2008
websites | general | education | energy efficiency

Shed and Garage Solar Lighting
Light your shed or garage with solar powered lighting
Article Last Modified: 16:47, 12th Nov 2008
lighting | solar

Convert Digital Mains Timer To Low Voltage
Convert a cheap digital mains timer into a low voltage programmable timer relay
Article Last Modified: 10:21, 15th Nov 2008
electronics | electric circuit | general

Efergy eLite Wireless Energy Monitor
Find out more about the new Efergy eLite wireless electricity monitor
Article Last Modified: 15:25, 14th Nov 2008
shopping | general | carbon

Smart Electricity Meters
Find out about smart meters and real time electricity pricing
Article Last Modified: 12:31, 3rd Jun 2008
energy efficiency | carbon | general

Free VAWT Wind Turbine Plans
Make your own 250 Watt vertical axis wind turbine (VAWT)
Article Last Modified: 09:31, 28th Dec 2006
wind | education

Save Electricity with a Spin Dryer
Find out more about how a spin dryer could save you money and save electricity
Article Last Modified: 13:05, 27th Jun 2008
energy efficiency | shopping

© 2006-2008 REUK - All Rights Reserved
Page Last Updated on 18th November 2008 at 01:51:59pm

Latest
Articles


REUK Poultry Lighting System
Buy the tried and tested REUK poultry lighting system
solar
10:21, 15th Nov 2008

Solar Powered Poultry Lighting
Put together a solar system to power poultry lighting - increase winter egg production
solar
10:21, 15th Nov 2008

Convert Digital Mains Timer To Low Voltage
Convert a cheap digital mains timer into a low voltage programmable timer relay
electronics
10:21, 15th Nov 2008

Efergy eLite Wireless Energy Monitor
Find out more about the new Efergy eLite wireless electricity monitor
shopping
15:25, 14th Nov 2008

Efergy homeCO2meter
New wireless electricity usage meter - homeCO2meter from Efergy
shopping
15:15, 14th Nov 2008

Efergy homeCO2meter Review
Read an REUK.co.uk review of Efergy's homeCO2meter electricity usage meter
energy efficiency
15:15, 14th Nov 2008

Shed and Garage Solar Lighting
Light your shed or garage with solar powered lighting
lighting
16:47, 12th Nov 2008

12 Volt Deep Cycle Batteries for Solar
Buy deep cycle 12V batteries for small scale solar powered projects
storage
16:27, 12th Nov 2008



REUK Shop

Popular Items


12 VOLT 3 WATT SOLAR PANEL
Waterproof 12 Volt 3 Watt Solar Panel - 199 x 136mm with fitted leads (fiberglass and resin).
£19.99 each.
Solar Power



EFERGY HOMECO2METER
efergy homeCO2meter wireless electricity monitor
£38.99 each.
Energy Saving



6V 250MA SOLAR PANEL
Waterproof 6 Volt 250 milliamp (1.5 Watt) Solar Panel - 130 x 135mm with fitted leads (fiberglass and resin)
£13.99 each.
Solar Power



300 WATT POWER INVERTER
Convert 12V DC battery power into 230 AC to power portable televisions, computers, video recorders etc. 300 Watt power rating - peak power 600 Watts
£29.99 each.
Renewable Energy System Parts



SOLAR PUMP CONTROLLER WITH RELAY
Solar water heating system microprocessor controlled circuit with fitted 10A relay
£25.99 each.
Complete Circuits



SUNSAVER 10A SOLAR CONTROLLER
10 Amp at 12 Volt solar charge controller - epoxy encapsulation, marine rated terminals
£35.99 each.
Solar Controllers