Battery Showdown: Lead-Acid vs. Lithium-Ion

Which is the best battery for an off grid energy system?

I have seen so many off grid energy systems with defunct lead-acid batteries. They work as designed for a few years if you are careful, and then they lose their depth of charge. I’ve been working with Lithium-Ion batteries over the past year, and while significantly more complex, they have some amazing advantages. Based on my experience, I predict that in a few years, we’ll move away from lead-acid batteries.

I believe right now we are at a clear crossroads when it comes to choosing a battery type for energy storage for off grid energy systems. We are at the transition between lead-acid batteries, the tried-and-true technology used for decades, and lithium-ion’s promise of higher density, improved resiliency, and longer cycle life.

Recently we’ve seen companies successfully gain traction with cost effective lithium-ion technologies. Li-Ion batteries are selling for as low as $400/kWh. TeslaLG ChemicalSonnenSimpliphi Power, and Lithionics all have reliable products at reasonable prices. And recently the German car manufacturer Mercedes-Benz announced that they are also getting into the stationary storage market with Mercedes-Benz Energy.

Battery Density Comparison
Initial Cost per Battery Capacity
Total Lifecycle Cost Lead Acid and Lithium-Ion