Lead Acid batteries are the most widely used rechargeable battery.You can find this type of battery in your inverter, car, motorcycle, emergency lighting system and in many other places. Usually it has a lifespan of 12 to 48 months but proper maintenance and repairing can extend its lifespan up to 3 to 4 time than its usual.

What is Lead Acid battery?  

Lead Acid battery is a secondary type of battery. It is made up of spongy lead (Pb), lead dioxide (PbO2) and dilute sulfuric acid. Lead dioxide is acts as positive electrode, lead as negative electrode and sulfuric acid as electrolyte. The chemical reaction of lead and lead dioxide with sulfuric acid produce electricity. Lead electrode produce positive ions, this ions is stored on lead dioxide and lead dioxide produce negative ions, this ions is stored on  spongy lead. This chemical reaction makes lead plate to negative and lead dioxide plate to positive.

Construction and working:

  

What are the common problems can be found in a used Lead Acid battery?

After long time use a Lead Acid battery can show lower capacity than its usual. Actually its internal resistance increases due to sulfation and it delivers lower current flaw and some time its voltage decreases.

 What is Sulfation?

When any lead acid battery discharges, soft lead sulfate (PbSO4) crystals formed on positive and negative plates. If a battery is left in a discharged condition, continually undercharged, or the electrolyte level is
below the top of the plates, some of the soft lead sulfate re-crystallizes into hard lead
sulfate. A crystallize lead sulfate is a non-conductive material and it cannot be reversed during normal recharging. This creation of hard crystals is commonly called permanent "sulfation". The longer sulfation causes the thicker and harder the lead sulfate crystals on the plates. These crystals diminish a battery's capacity and ability to be recharged to its full capacity.