Choosing the Right Battery: Lead Acid vs Lithium
The battery bank is often the most expensive component of an Off-Grid or Hybrid solar system. While the "Ah" rating matters, the chemistry matters more in 2026.
1. Tubular Lead Acid Batteries (C10)
These are the tall, heavy batteries you see in most Indian homes. They are reliable and cheap.
- Life: 3-5 Years (approx 1200 cycles).
- Maintenance: High. Requires distilled water topping every 3-6 months.
- Efficiency: low (70%). You lose energy as heat during charging.
- Depth of Discharge (DoD): Can only use 70% of capacity. If you drain it more, life reduces drastically.
2. Lithium Ferro Phosphate (LFP)
The modern choice. They work like your phone battery but bigger.
- Life: 10-15 Years (4000+ cycles).
- Maintenance: Zero. Sealed unit.
- Efficiency: High (95%). Fast charging (can charge fully in 2 hours vs 10 hours for Lead Acid).
- Depth of Discharge (DoD): Can use 90-95% of capacity.
Sizing for Solar vs Regular Inverter
Solar batteries are rated C10, meaning they are designed to discharge over 10 hours (perfect for night loads). Regular inverter batteries are C20 (discharging over 20 hours). Always insist on C10 Solar Batteries if you are connecting them to panels, as they handle the daily charge-discharge cycle much better.
How long will my battery last?
If you have a 150Ah / 12V battery:
- Load 200 Watts (Fans+Lights): Lasts ~7 hours.
- Load 400 Watts (TV+PC+Fans): Lasts ~3.5 hours.
- Load 800 Watts (Mixer/Iron): Lasts ~1.5 hours.