A flooded battery, also known as a wet cell battery or vented battery, is a type of lead-acid battery. It is called "flooded" because it contains a liquid electrolyte solution that floods the cells within the battery. This electrolyte is typically a mixture of water and sulfuric acid.

Flooded batteries consist of several lead-acid cells connected in series. Each cell contains a series of lead dioxide (PbO2) plates as the positive electrode and sponge lead (Pb) plates as the negative electrode, immersed in the electrolyte solution.

Here are some key characteristics and features of flooded batteries:

  • Maintenance: Flooded batteries require regular maintenance. This includes checking and topping up the electrolyte levels with distilled water, cleaning terminals, and ensuring proper ventilation.
  • Durability: Flooded batteries are known for their durability and longevity when properly maintained. They can endure a large number of charge and discharge cycles.
  • Low Cost: Compared to some other battery technologies, flooded batteries are relatively inexpensive to manufacture and purchase.
  • Deep Discharge: They can handle deep discharge cycles, making them suitable for applications where occasional deep discharges are common.
  • Venting: These batteries are designed with vents to release gases produced during charging. Proper ventilation is essential to prevent the buildup of hydrogen gas, which can be explosive in high concentrations.
  • Applications: Flooded batteries are used in various applications, including automotive starting batteries, backup power systems, uninterruptible power supplies (UPS), and in off-grid renewable energy systems like solar and wind power.

Environmental Considerations: Disposing of flooded batteries requires proper recycling due to the presence of lead and sulfuric acid, both of which can be harmful to the environment if not handled correctly.

While flooded batteries offer certain advantages, such as their low cost and resilience, they also come with the responsibility of regular maintenance and precautions to ensure safe and efficient operation. For applications where maintenance is a concern, GEL or AGM batteries are alternative options that require less maintenance.