LFP vs NMC: Choosing a Battery for Solar Storage

Most solar batteries today are lithium-ion, but "lithium-ion" covers several chemistries. For home and business storage, the two you'll meet most are LFP (lithium iron phosphate) and NMC (nickel manganese cobalt). They behave differently in ways that matter for safety, lifespan and cost.

At a glance

Exact numbers depend on the product, so always read the datasheet and warranty.

Why LFP leads in stationary storage

A battery on a wall or in a container doesn't need to be light. What matters is that it's safe, lasts many years and costs little per stored kilowatt-hour over its life. LFP fits that well, which is why most new home batteries use it.

When NMC still makes sense

NMC packs more energy into less space and weight. That helps in vehicles and where space is tight. Some older home batteries use NMC and still perform well.

The numbers that matter

• Usable capacity: the energy you can actually use, often 90 to 100% of the rated capacity for LFP
• Power (kW): how much the battery can deliver at once, which decides whether it can run large loads
• Cycles and warranty: look for a warranty that guarantees remaining capacity (for example 70% after 10 years)
• Round-trip efficiency: how much energy you get back, typically around 90%
• Compatibility: the battery must work with your inverter

Sizing a battery

Start with what you want it to do. To use more of your own solar, size it near your typical evening use. For backup, multiply the power of the essentials you want to keep running by the hours you need. Our solar calculator gives a quick estimate, and our partners can design a storage system for your home or business.