Topic Content:
- Meaning of Lead Acid Accumulator
- Lead Accumulator Discharging
- Lead Accumulator Recharging
- Difference between Primary and Secondary Cell
The lead acid accumulator is used in car batteries. It is also called a storage cell because it must be charged by passing current through it.
In a lead storage battery, the anodeAn anode is an electrode of a polarized electrical device through which conventional current enters the device. It is the positive part of electrolytes where oxidation takes place. More is metallic lead and the cathodeA cathode is the electrode from which a conventional current leaves the electrolyte. It is the negative part of the cell where reduction takes place. More is lead(IV) oxide. The electrolyteAn electrolyte is a substance that dissociates in water into charged particles called ions. Positively charged ions are called cations. Negatively charged ions are called anions. Simply, an electrolyte is a... More is dilute tetraoxosulphate(VI) acid solution. When the two electrodes are connected to an external circuit, it produces electricity by discharging.
Lead Accumulator Discharging:
At the Anode (Discharging):
When in use as a source of direct current the accumulator discharges:- The Lead atoms release two electrons each to be oxidized to Lead(II) ions, Pb2+, which combine with tetraoxosulphate(VI) ions [SO42- ], in the electrolyte to become deposited on the anode as lead(II) tetraoxosulphate (IV), PbSO4
Pb(s) → Pb2+(aq) + 2e–
Pb2+(aq) + SO42–(aq) → PbSO4(s)
The electrons released pass round an external circuit as an electric current and can be used in:
- starting the engine of vehicle,
- lighting up of car lamps before arriving at the cathode.
At the Cathode (Discharging):
The electrons are accepted at the cathode, lead(IV) oxide and the hydrogen ions from the electrolyte undergo redox reaction as follows:
You are viewing an excerpt of this Topic. Subscribe Now to get Full Access to ALL this Subject's Topics and Quizzes for this Term!
Click on the button "Subscribe Now" below for Full Access!
Subscribe Now
Note: If you have Already Subscribed and you are seeing this message, it means you are logged out. Please Log In using the Login Button Below to Carry on Studying!
Responses