Lithium Iron Phosphate battery:
Lithium Iron Phosphate Battery is a rechargeable types of battery which features lithium ions that moves from the negative electrode to the positive electrode during discharge and comes back to its original points while charging.
Fig: Schematic of working mechanism of Lithium-iron phosphate battery
Advantages of Lithium Iron Phosphate (LiFePO4) battery:
Smaller and lighter: Lithium Iron Phosphate (LiFePO4) battery is lighter than other rechargeable batteries in consideration of battery capacity. This makes it more practical in portable consumer electronic devices in which physical specifications such as weight and form factor are considered important selling points. Generally lithium battery weight is 30% from the lead acid batteries.
High efficiency: Most lithium-ion batteries have more than 95% efficiency (in 1C discharge), meaning that 95 percent or more of the energy stored in a lithium-ion battery is actually able to be used in 1C discharge. Conversely, lead acid batteries see efficiencies closer to 50% in 1C discharge.
Fast charging ability: Lithium batteries have superior fast charging ability over Lead acid batteries. With appropriate battery charger, then can be 90-100% charged within 1-3hours where as general lead acid batteries take more than 10-12 hours to fully charge.
High energy density: This is one of the highlighted advantages of lithium iron phosphate battery technology. With the increased density of energy this battery technology is being used from smart phones to the high end electric vehicles. The theoretical energy density of lead acid is 35-50 Wh/kg where as lithium batteries have usually 120-260Wh/kg.
Depth of discharge: Lead-acid batteries should only be run to 50% depth of discharge. Beyond that point, you risk negatively affecting their lifespan. In contrast, lithium batteries can handle deep discharges of 80% or more. This essentially means they feature a higher usable capacity.
Self-discharge: Other rechargeable batteries are not good with the rate of self-discharge. Due to the existence of Lithium iron cells in the battery the self-discharge rate is quite lower than others. It is around 5% for the first four hours and drops to around 1-2% per month.
Low maintenance: It does not require constant maintenance to continue its flawless performance whereas Lead-acid is a tried-and-true technology that costs less, but requires regular maintenance and doesn’t last as long.
Availability of variety: There are several types of lithium ion cells which can be used accordingly as per the requirement for a particular application.
Zero to low memory effect: Lithium Iron Phosphate (LiFePO4) battery has zero to minimal memory effect. This memory effect is common in nickel-metal hydride rechargeable batteries such as NiCd and NiMH.
High open-circuit voltage: Lithium Iron Phosphate battery has a chemistry that results in higher open-circuit voltage than other aqueous batteries such as lead acid, nickel-metal hydride, and nickel-cadmium.
The Lithium Iron Phosphate Battery have eventually become popular and its demand has drastically grown up to much greater extent in past few years. There are various lithium iron phosphate battery manufacturers who have been producing such batteries to fulfill the needs as per the demand and fill the gap between the demand and supply. But we need to understand the advantages and the limitations of this technology for choosing the right backup battery for us.
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