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it can give a very large electric current for starting an engine. A lead-acid
storage cell goes flat when sulfuric acid is gradually converted into water and
the electrodes are converted into lead sulfate (PbO4). When the lead-acid
battery is recharged, these chemical reactions are reversed until the chemicals
have been restored to their original condition. A lead-acid battery has a useful
life of about two to three years and they produce about 2V per cell.
Nickel-iron battery
A secondary cell widely used in heavy industry is nickel-iron battery. The
principle of operation is the same as in the lead-acid cell. The only exception is
that the negative electrode consists of iron and the positive electrode is made of
nickel oxide (Ni2O3). The electrolyte is a solution of potassium hydroxide
(KOH). The nickel-iron cell has the disadvantage of emitting hydrogen gas
during charging.
Cadmium battery (nickel-cadmium cell)
This is also very similar to nickel-ion battery. Here negative iron
electrode is replaced by cadmium electrode. The positive electrode is nickel
oxide. Some nickel-cadmium batteries gradually lose their maximum energy
capacity if they are repeatedly recharged after being only partially discharged –
this phenomenon of losing energy capacity is called “memory effect”.
Lithium-ion battery
This is a rechargeable type of battery in which a lithium ion moves
between the anode and the cathode. This type of battery is very commonly
used in consumer electronics, laptop computers, cell phones, video games, etc.
Because of the best energy-to-weight ratios, no memory effect and a slow loss
of charge when not in use, they are one of the most popular types of battery for
portable electronics.
Underline the main information on some necessary characteristics of
batteries with a straight line, secondary information with a wavy line
Match the battery types with their applications
1. Lithium-ion battery …
2. Mercury cell …
3. Alkaline dry cell …
4. Lead-acid battery …
a) is used in vehicles;
b) is used in cell phones and laptop computers;
c) is used in wristwatches and calculators;
d) is used in remote controls and torches.
Find the article on the topic «Battery», make its summary, report on
the article to your groupmates
