How long does a lithium battery last?

The storage capacity of lithium (LFP) battery systems is typically measured in kWh (Kilowatt hours), while the most common metric used to determine battery lifespan is the number of charge cycles until a certain amount of energy is lost. This generally ranges from 3000 to 5000 cycles over a battery life of 10 to 15 years.

What degradation mechanisms shorten battery life in stationary storage applications?

As detailed below, there are several well-studied degradation mechanisms that shorten battery life in stationary storage applications, including electrode degradation, where lithium plating on the anode and graphite structure breakdown occur under low state of charge (SoC) conditions.

What happens if a lithium battery goes bad?

The increased cycling range increases the chance that some lithium ions will not return to the electrolyte, resulting in a gradual loss of capacity (often called capacity fade). The loss of active lithium ions reduces the overall energy that the battery can store, leading to a shorter lifespan and lower performance.

Why is a lithium battery not discharged below 20% SoC?

In general, most lithium battery systems are not discharged below 20% SOC to ensure some capacity is left for emergency situations and, in some instances, to ensure the battery is operated within the manufacturer’s warranty specifications. State of health (SOH) is a percentage of how much battery capacity is remaining.

Does a high lithium iron phosphate battery cause battery wear?

In addition to some manufacturers’ warranty limits regarding DOD, research shows that high DOD cycling lithium iron phosphate (LFP) batteries, such as discharging down to 5 or 10% SOC daily, accelerate battery wear significantly compared to discharging down to 20 or 25% SOC.

What are the risks of deep discharging lithium iron phosphate batteries?

In addition to reduced lifespan, deep discharging lithium iron phosphate (LFP) batteries pose several risks due to the nature of their voltage curves and the sensitivity of inverters and battery management systems (BMS) to low voltage conditions. Here are the main issues encountered when discharging lithium batteries to very low levels: