Lead Acid Batteries: Advantages and Disadvantages

This article discusses the advantages and disadvantages of lead acid batteries, along with a basic introduction to their construction and function.

What is a Lead Acid Battery?

• A battery is a device that stores electrical power.
• As shown in Figure 1, a lead acid battery typically contains six cells, each producing approximately 2V.
• The materials used in a lead acid battery are lead peroxide (PbO2), sponge lead (Pb), and dilute sulfuric acid (H2SO4).
• The positive plate is made of PbO2, a dark brown, hard, and brittle substance.
• The negative plate is made of pure lead in a soft, sponge-like condition (Pb).
• The electrolyte is H2SO4, with a water to acid ratio of approximately 3:1.

Lead Acid Battery construction

Advantages of Lead Acid Batteries

Here are the benefits of using lead acid batteries:

• Wide Availability: They are available in various shapes and sizes to suit different applications.
• Low Maintenance: They generally don’t require much maintenance.
• Reliable Performance: They are known for their reliability and consistent working capabilities.
• Charge Tolerance: They can withstand slow, fast, and even overcharging to some extent.
• Inactivity Tolerance: They can withstand long periods of inactivity, with or without a solvent.
• Cost-Effective: They offer the best value in terms of power and energy per KWH.
• Long Lifespan: They are known for their long life cycle.
• Recyclable: Approximately 97% of the lead in these batteries can be recycled and reused in new batteries.
• Inexpensive to Manufacture: They are simple and inexpensive to manufacture, resulting in a low cost per watt-hour.
• Low Self-Discharge: They have a low self-discharge rate, which is among the lowest for rechargeable batteries.
• Temperature Performance: They offer good performance at both low and high temperatures.

Disadvantages of Lead Acid Batteries

Here are the drawbacks of using lead acid batteries:

• Heavy Weight: Lead is a relatively heavy element compared to alternatives, making the batteries bulky.
• Low Specific Energy: They have a low specific energy, resulting in a poor weight to energy ratio.
• Slow Charging: They charge relatively slowly; a full charge can take 14 to 16 hours.
• Storage Requirements: They must be stored in a charged condition to prevent sulfation, which can damage the battery.
• Limited Cycle Life: They have a limited cycle life, and repeated deep cycling can significantly reduce battery life.
• Watering (Flooded Batteries): Flooded versions of lead acid batteries require periodic watering to maintain electrolyte levels.
• Environmental Concerns: They are not environmentally friendly due to the lead and sulfuric acid content.
• Transportation Restrictions: There are transportation restrictions on flooded-type lead acid batteries due to the risk of spillage.