Tools that convert chemical energy and convert it into electrical energy and store it to convert electrical energy into chemical energy are called accumulators.
When electrical energy is taken from an accumulator, there are some chemical changes in the electrolyte and electrodes, and after a while, Emk drops. When a reverse current is passed through this accumulator, chemical changes occur in the electrolyte and electrodes and the Emk of the battery increases.
The active substance of a negative battery of a charged battery is spongy (porous) lead (Pb), dark brown color lead (Pb O2) of the positive plate, and aqueous sulfuric acid with a density of 1.27.
The amount of electrical energy drawn from an accumulator depends on the amount of substance entering the chemical change. It is desirable that the amount of active substance in the plates in contact with the electrolyte is as high as possible. There are many positive and negative plates in a battery for this. The positive plates were connected by a bridge and the two ends were removed. The positive end is called the positive pole of the battery and the negative end is called the negative pole of the battery.
The negative structure of a battery and placement of the plates can be seen in the battery section. The negative structure and placement of the plates in an accumulator is seen in the battery section. The number of negative plates in an accumulator is one more than the number of positive plates. Placement of plates is shown with separators. The active substance in the plates is filled into grid-shaped cages made of lead-antimony alloy.
(2) Chemical Events in the Discharge of a Leaded Battery:
Let’s start discharging the charged battery by closing its switches. Aqueous sulfuric acid consists of positively charged hydrogen (H2 +) and negatively charged sulfate (So4-) ions. By giving the sulfate ion negative charge to the lead plate, it combines with lead and lead sulfate (PbSo4) is formed. The sulfate ion combines with lead by giving its negative charge to the lead plate and goes to the lead sulfate plate, after giving its charge to this plate, the lead peroxide combines with the oxygen of the plate to form water (H2O). The hydrogen ion of sulfuric acid in contact with the lead peroxide plate combines with the oxygen of the lead peroxide to form lead sulfate (PbSo4). Thus, in both plates, lead turns into sulphate. The battery continues to supply current to the external circuit until both boards turn into lead sulphate. Because when two boards in electronics are of the same type, the potential difference between the boards becomes zero.
Three changes occur at the time of battery discharge:
1. The acid density in the electrolyte is weakened. This lowers Emk.
2. The active ingredients of the plates turn into lead peroxide and lead to lead sulphate.
3. The internal resistance of the battery grows, Emk drops.