Rainy and overcast weather directly impacts the performance of lead-acid batteries in photovoltaic (PV) systems. Since solar panels generate less electricity under low-light conditions, the batteries receive insufficient charge, leading to gradual discharge.
Prolonged undercharging causes sulfation—a buildup of lead sulfate crystals on the battery plates—reducing capacity and lifespan. Additionally, high humidity in rainy seasons can accelerate corrosion on battery terminals, increasing internal resistance.
Mitigation Tips:
- Ensure proper system sizing to account for low solar input days.
- Use charge controllers with temperature compensation to optimize charging.
- Keep terminals clean and apply anti-corrosion grease.
