The lithium iron phosphate (LiFePO4) battery, also called LFP battery (with “LFP” standing for “lithium ferro phosphate”), is a type of rechargeable battery, specifically a lithium-ion battery, using LiFePO4 as the cathode material, and a graphitic carbon electrode with a metallic backing as the anode.
Lithium Ferro Phosphate technology (also known as LFP or LiFePO4), which appeared in 1996, is replacing other battery technologies because of its technical advantages and very high level of safety.
Due to its high power density, this technology is used in medium-power traction applications (robotics, AGV, E-mobility, last mile delivery, etc.) or heavy-duty traction applications (marine traction, industrial vehicles, etc.)
The long service life of the LFP and the possibility of deep cycling make it possible to use LiFePO4 in energy storage applications (stand-alone applications, Off-Grid systems, self-consumption with battery) or stationary storage in general.
Major advantages of Lithium Iron Phosphate LiFePO4:
○ Very safe and secure technology (No Thermal Runaway)
○ Very low toxicity for environment (use of iron, graphite and phosphate)
○ Calendar life > 10 ans +
○ Cycle life : from 2000 to several thousand (see chart below)
○ Operational temperature range :up to 70°C
○ Very low internal resistance. Stability or even decline over the cycles.
○ Constant power throughout the discharge range
○ Ease of recycling
○ Life-cycle of Lithium Iron Phosphate technology (LiFePO4)
The actual number of cycles that can be performed depends on several factors:
○ Level of power in C-Rate
○ Depth of Discharge (DOD)
○ Operational environment: temperature, humidity, etc.
The chart shows the estimated number of cycles for Lithium Iron Phosphate LiFePO4 cells (LFP, LiFePO4) according to the discharge power and DOD figures. The test conditions are those of a laboratory (constant temperature of 25 ° C, constant charging power and discharge).
In standard environment, and for 1C cycles, we can get from the chart the below life cycle estimation for LFP :
○ 2000 cycles at 100% DoD
○ 5000 cycles at 80% DoD
○ 6500 cycles at 55% DoD
It should be noted that following the number of completed cycle, the batteries still have a nominal capacity > 80% of the original capacity.