The Editorial team

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Actually, it isn't that lightning is captured and trapped in the cell, as children think. And nor it is that a cell supplies current to the circuit, as many grown-ups think. We will see what's in an electric cell which helps power portable appliances.

The Parts
Let's begin with familiarizing ourselves with components of the electric cell. It contains-
- Two electrodes (Zinc and Manganese dioxide)
- An electrolyte
- Two terminals
- A Carbon rod (to collect electrons)


How it Works
One of the electrodes (called the Anode, made up of Zinc) gradually starts dissolving in the electrolyte (ammonium chloride) i.e. its atoms break into positive ions in the electrolyte and the electrons are collected by the carbon rod. The other electrode doesn't dissolve easily in the electrolyte, instead it loses electrons to the positive Zinc ions in the electrolyte and becomes deficient in them. So the electrons absorbed by the carbon rod move through the circuit to fulfil the deficiency at the other (positive) end. Old cells become weak after much use, as hydrogen bubbles start forming on the carbon rod surface, which shrinks the electron absorption.

The Pioneers
The spark for the concept of batteries lit up as soon as electricity itself. A fellow anatomist, Luigi Galvani noticed the twitching of dead frog legs hung on copper hooks on an iron nail. He thought (wrongly) of it's case being ‘animal electricity'. Another professor, Alessandro Volta invented the voltaic cell in 1800 opposing this very idea.

The Mystery
The year 1938. An unusual set of vases have been discovered by a German archaeologist in ancient Baghdad, which are as said to be of the Parthian period of 250BC. The 13 cm tall clay pots contained a copper vessel with and iron rod in it, sealed with asphalt. When an acidic agent such as fruit juice was put in the vessel, the vases functioned as batteries, generating enough current to power a small digital clock. It is still unclear for what purpose it might have been used. Priests are said to have put these inside statues as they could give a slight shock if touched, convincing the devotee about the powers of the god, priest, or (as the priest knew) the cell.
The Greeks used electric eels to numb pain, while the Chinese used acupuncture with small electric currents. Another application could have been to electroplate vessels, coins and jewelry. Copper vessels with thin silver coatings have been excavated from nearby Sumerian sites which researchers have achieved with replicas of the battery. This makes the batteries as old as 2500BC or ,ore than 4500 years old.

The Fun Part
Bizarre as it seems, potatoes can do function as cells since small amounts of salt and phosphoric acid act as the electrolyte. To make one, we require,
- Copper and Zinc Electrodes (copper coin and galvanized nail can be used as alternatives)
- An LED or multimeter
- Copper wire and Alligator clips (for securing the wire to the electrode)

The electrodes are to be inserted deep into the potato keeping at least an inch's distance in between. The copper wire connects the copper electrode to the positive terminal of the LED and the Zinc electrode to the negative terminal. To generate more power, multiple potatoes can be used, with copper electrode of one connected to the galvanised nail of the other. Other fruits and vegetables with salts and acids can also be used.

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