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What is battery sulfation?

How does battery sulfation occur?

Battery sulfation occurs when a battery is undercharged or deprived of a full charge. Every time that a battery doesn’t complete a full charge it build-up a sulfate. A sulfation is normal on a battery, where small sulfate crystals build up during use of it. It’s normals and not harmful for the battery.However, if the battery is regularly not being fully charged , the amorphous lead sulfate converts to a crystalline that’s more stable and deposits itself on the negative plate. This tends to grow like all salt crystals and hinders the negative active material from taking part in the battery reactions completely.

What is the sulfation of a battery?

Sulfation of batteries, especially at the cathode, is a major cause of battery failure. Lead sulphate is sparingly soluble in water (5 mg/liter) and the solubility decreases as the acid concentration increases above 1.05 Lead sulphate continuously dissolves and reprecipitates in dynamic equilibrium with the solutes. For extended periods of time, when batteries are stored inactive, at high temperatures, this can lead to the formation of fine powdered lead sulfate into hard crystals.

This lead sulphate also increases the internal resistance of the battery.

Signs of battery being sulphated? Battery sulfation symptoms

  • Reduced battery capacity

  • Reduced specific gravity of electrolyte

  • Higher charging voltage and poor charge reception

  • Early aeration

  • Swelling of active material and loss of large masses

  • Patches that change color and feel gritty to the touch

What is the effect of battery sulfation?

There are two types of sulphide batteries, reversible and irreversible sulphide. If the battery is serviced immediately, the reversible sulphation can be corrected by over-discharging the fully charged battery to break up the crystals.

Permanent battery sulphation occurs when a battery is discharged unattended for weeks or months. Under this condition, the crystals reach such a size that the cathode plates are white. It is very difficult to restore such sulphated batteries.

What causes battery sulphide? Battery Sulfation Explained!

There are many possible causes of battery sulphide. Below are the main factors that cause sulfation of a battery

  • causing the battery to discharge for a long time

  • Batteries are often fully charged

  • Low electrolyte level or electrolyte level drops below the top of the plate

  • Battery storage at high temperature

  • Lack of action fix on lagging cells.

  • Improper filling with acidic electrolyte instead of deionized water

  • High temperature operation

  • Frequent undercharge or low float voltage

  • Electrolyte stratification.

  • left to sit in the hot climate accelerates the process

How to avoid battery sulfation?

If you need to store the battery for a long time, fully charge it first. Then plug it into a smart charger to keep the battery low or charge afloat. This will ensure that the battery will not be sulphated.

What is the blue powder on my battery terminals?

Battery Treatment Chemical for Sulfate, The white powder you see around the battery terminals is lead sulfate. When the terminals have copper inserts for better electrical conductivity, the copper will react with sulfuric acid to form copper sulfate. Anhydrous copper sulphate glows green. This can be simply washed away once a year with baking soda & water. Always keep the battery terminals clean & coated with a thin layer of petroleum jelly, not grease.

How to get rid of battery sulfation?

long downloads with small current: This method is recommended for low or soon. Sulfate cells are covered with distilled water. Download to normal line to remarkable gas stage. Rest in half an hour and recharge until one-tenth of normal charging current until abundance is observed. Rest for another 30 minutes. Deposit with the low rate above. This is repeated several times until the specific gravity and charge voltage of the cell remain constant near normal values. A slight adjustment to the required density level can be made.

How to avoid battery sulfation?

Proper battery charging ensures a long life for your investment. Batteries are now an indispensable part of our lives. It is also the most expensive item to replace every 3 years, depending on design needs. Care should be taken to properly charge the battery regularly to avoid premature failure. The sulfation of the battery can be easily avoided.


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