Comparison of lead-acid and lithium batteries
Lead-acid batteries have a lower initial cost, but have a shorter lifespan and require regular maintenance to keep them working properly. Lithium batteries have a much higher initial cost, but are maintenance free and last longer to match their higher price. This article provides a side by side comparison of the two options.
Lithium
The best lithium battery chemistry for solar applications is lithium iron phosphate, short for LiFePO4 or LFP cells. This new technology lasts longer and can go through deeper cycles. They also do not require maintenance or ventilation, unlike lead-acid batteries.
Lithium batteries have a higher initial cost, but the higher efficiency means you can lower your cost per kWh of capacity over the life of the battery.
Lead Acid vs. Lithium Batteries: Price Breakdown
Let's see how much it costs to build a battery pack using all three options.
We are not only interested in the initial cost, but also the cost of ownership over the life of the system. As an example, we'll look at the cost of the batteries to power this 5.13 kW off-grid system, which sold for $12,899 at launch.
In an off-grid environment, you'll want to see the estimated cycle life because you're cycling the battery every day. It is estimated that the system will generate 23.08 kWh per day in summer and 11.54 kWh per day in winter.