06-09-2017, 10:57 AM
A lemon battery is a simple battery often made for the purpose of education. Typically, a piece of zinc metal (such as a galvanized nail) and a piece of copper (such as a penny) are inserted into a lemon and connected through the wires. The energy generated by the reaction of the metals is used to power a small device such as a light emitting diode (LED).
The lemon battery is similar to the first electric battery invented in 1800 by Alessandro Volta, who uses brine (salt water) instead of lemon juice. The lemon battery illustrates the type of chemical reaction (oxidation-reduction) that occurs in the batteries. Zinc and copper are called electrodes, and the juice inside the lemon is called the electrolyte. There are many variations of the lemon cell that use different fruits (or liquids) like electrolytes and metals other than zinc and copper as electrodes.
There are numerous sets of instructions for manufacturing lemon batteries and for obtaining components such as LEDs, electric meters (multimeters) and zinc coated (galvanized) nails and screws. Commercial "potato watch" science kits include electrodes and a digital low-voltage clock. After mounting a cell, a multimeter can be used to measure the voltage or electric current of the voltaic cell; a typical voltage is 0.9 V with lemons. The currents are more variable, but vary up to about 1 mA (the larger the electrode surface, the greater the current). For a more visible effect, the lemon cells can be connected in series to power an LED (see illustration) or other devices. The serial connection increases the voltage available for the devices. Swartling and Morgan have published a list of low voltage devices along with the corresponding number of lemon cells that were needed to feed them; included LEDs, piezo buzzers and small digital clocks. With the zinc / copper electrodes, at least two lemon cells were needed for any of these devices. Replacement of a magnesium electrode by the zinc electrode causes a cell to have a higher voltage (1.5-1.6 V), and a single magnesium / copper cell will power some devices. Keep in mind that incandescent flashlight bulbs are not used because the lemon battery is not designed to produce enough electrical current to illuminate them. By multiplying the average current of a lemon (0.001A / 1mA) by the average (lowest potential) voltage of a lemon (0.7V) we can conclude that it would take more than 6 million lemons to give us the power of an average car battery of 4320W.
The lemon battery is similar to the first electric battery invented in 1800 by Alessandro Volta, who uses brine (salt water) instead of lemon juice. The lemon battery illustrates the type of chemical reaction (oxidation-reduction) that occurs in the batteries. Zinc and copper are called electrodes, and the juice inside the lemon is called the electrolyte. There are many variations of the lemon cell that use different fruits (or liquids) like electrolytes and metals other than zinc and copper as electrodes.
There are numerous sets of instructions for manufacturing lemon batteries and for obtaining components such as LEDs, electric meters (multimeters) and zinc coated (galvanized) nails and screws. Commercial "potato watch" science kits include electrodes and a digital low-voltage clock. After mounting a cell, a multimeter can be used to measure the voltage or electric current of the voltaic cell; a typical voltage is 0.9 V with lemons. The currents are more variable, but vary up to about 1 mA (the larger the electrode surface, the greater the current). For a more visible effect, the lemon cells can be connected in series to power an LED (see illustration) or other devices. The serial connection increases the voltage available for the devices. Swartling and Morgan have published a list of low voltage devices along with the corresponding number of lemon cells that were needed to feed them; included LEDs, piezo buzzers and small digital clocks. With the zinc / copper electrodes, at least two lemon cells were needed for any of these devices. Replacement of a magnesium electrode by the zinc electrode causes a cell to have a higher voltage (1.5-1.6 V), and a single magnesium / copper cell will power some devices. Keep in mind that incandescent flashlight bulbs are not used because the lemon battery is not designed to produce enough electrical current to illuminate them. By multiplying the average current of a lemon (0.001A / 1mA) by the average (lowest potential) voltage of a lemon (0.7V) we can conclude that it would take more than 6 million lemons to give us the power of an average car battery of 4320W.