What is Sulphation in Batteries and their Types

Batteries are devices that supply electricity to do work by converting the chemical energy to electrical energy. There are many types of batteries like Lead acid batteries, Lithium ion batteries etc. Lead acid batteries are widely used in various applications but it has some problems as well. This happens mostly with the batteries that are used for very high load applications like car batteries or inverter batteries.

What is Sulphation?

When the lead acid battery loses its ability to hold a charge after keeping it in the discharged state for a long time, it results in the formation of lead sulfate crystals on the surface and in the pores of the active material lead plates. Lead acid batteries perform chemical processes through double sulfate chemical reaction. 

The active material of the lead acid battery’s plate is made up of lead and lead oxide which reacts with the sulphuric acid present as electrolyte resulting in the formation of lead sulfate. When it is formed, it is in an amorphous state near the plates. When the battery is recharged, it is converted into the lead, lead oxide and sulphuric acid again.

But over time, after constant charging and discharging of the battery, the lead sulfate is permanently converted into crystallized form over the electrodes (cathode and anode). This form can neither conduct electricity nor it can be converted into lead or lead oxide again. 

Symptoms of Battery Sulfation

Sulfation is caused when a battery is overcharged, undercharged or discharged more frequently. There are symptoms to determine if sulfation is created or not such as:

1.Early gassing

2.Fall in electrolyte density

3.Discolouration of plates

4.Sandy/gritty feel to the touch

5.Higher charging voltage

Causes of Sulfation

All the lead acid batteries suffer the process of sulfation once, depending on the use and maintenance of batteries. It mostly happens when a chemical reaction occurs. Many other factors are there which causes sulfation like:

1.If the battery has a low electrolyte level, it will cause sulfation.

2.If the lead acid batteries are charged excessively or not charged enough or left discharged for a long time, it will cause sulfation over them.

3.If the battery is kept in very high or very low temperatures.

4.Mixing of wrong electrolyte or untimely adding up water or filling water which is not distilled can be a reason for sulfation in batteries.

5.If a battery is not provided with energy and is kept away for a long duration, it will end up forming sulfation on the top of the batteries.

Types of Battery Sulfation

Battery sulfation can be of two types namely:

1.Reversible Sulfation - This kind of sulfation is also known as Soft sulfation. This sulfation refers to the process where the sulfation can be reversed in a battery by overcharging the battery. Although, overcharging has its own cons.

2.Permanent Sulfation - This is also known as hard sulfation. Here the process of sulfation cannot be reversed and it is created permanently. This is known as Permanent sulfation.

It is very important to keep the battery in a properly charged state to avoid the formation of sulfation upon it. Formation of sulfation can lead to the condition of the battery to deteriorate very quickly. To avoid all that, there are certain additives that can be added to increase the life of the battery. 
Ulka being one of the topmost battery additives manufacturers produces various battery chemicals for tubular batteries to enhance their lifespan.