Lead-Acid Batteries

The lead-acid battery is one of the oldest and most widely used types of rechargeable batteries. Due to its simple structure, low cost, and ability to deliver high currents, it is commonly used in vehicles, industrial equipment, and backup power systems.

A lead-acid battery consists of positive and negative plates immersed in an electrolyte solution (usually diluted sulfuric acid). The positive plates are made of lead dioxide (PbO₂), and the negative plates are made of pure lead.

When the battery discharges, a chemical reaction occurs between the plates and the electrolyte, forming lead sulfate (PbSO₄) on both plates and generating electrical energy. During charging, this chemical reaction is reversed, converting the lead sulfate back into its original materials and storing energy in the battery.

Lead-acid batteries are divided into two main categories:

  • Wet Batteries: These contain liquid electrolyte and require regular maintenance.

  • Sealed Batteries: These use gel or absorbed electrolyte and require little to no maintenance. VRLA (Valve Regulated Lead Acid) batteries are safer due to their sealed design and are commonly used in applications such as UPS systems and solar power setups.

Advantages:

  • Low Cost: Lead-acid batteries are cheaper to manufacture compared to other types.

  • High Current Supply: They can deliver high surge currents.

  • Simple Design: Their simple construction keeps manufacturing costs low.

  • Wide Availability: Mass production makes them easily accessible everywhere.

Limitations:

  • Heavy and Bulky: They have a high weight and volume relative to their capacity.

  • Limited Lifespan: Their number of charge and discharge cycles is limited.

  • Sensitivity to Deep Discharge: Complete discharge can damage the plates and shorten battery life.

  • Risk of Acid Leakage: If damaged, sulfuric acid can leak, causing corrosion and environmental harm.

Applications:

  • Automotive Batteries: The most common use of lead-acid batteries is in vehicles.

  • UPS Systems: Used to supply power to critical equipment during outages.

  • Industrial Equipment: Widely used in forklifts, motorcycles, and boats.

  • Energy Storage Systems: Used on a small scale for storing solar and wind energy.