Useful table of typical voltages and values for VRLA, NiCd & LiFePO4 cells.

Why lithium iron phosphate (LiFePO4 ) batteries are suitable for industrial and commercial applications.

Why lithium iron phosphate (LiFePO4 ) batteries are suitable for industrial and commercial applications. A few years in the energy sector is usually considered a blink of an eye. This makes the rapid transformation of the battery storage market in recent years even more remarkable. The battery storage landscape in the electricity sector is moving away from NiCd; it has shifted towards lithium-ion batteries, as well as advanced lead-acid. For many applications, lithium-ion has proved preferable to other chemistries with respect to energy and power density, cycle and calendar life, and cost. The lithium-ion deep discharge cycle life, energy and power density, and other attributes have proved preferable over other battery types. In conjunction with rapid cost decreases, this has led to increased deployment of lithium-ion. (IRENA, 2015).

LiFePO4 compared with VRLA batteries

Lithium Iron Phosphate (LiFePO4) compared with Valve Regulated Lead-Acid (VRLA) Batteries

LiFePO4 compared with NiCd batteries

A comparison of Lithium Iron Phosphate (LiFePO4) with Nickel Cadmium (NiCd) batteries LiFePO4 batteries are very stable and safe, emit no flammable or toxic gasses, and contain no toxic or hazardous materials. LiFePO4 safe technology will not catch fire or explode with overcharging - they do not produce any flammable gasses under any circumstances LiFePO4 have almost twice the energy density than NiCad LiFePO4 weigh about one third to half of the weight of a NiCad battery of equivalent power 1000 to 5000 discharge cycles compared with the cycles from NiCad cells. LiFePO4 have relatively low self-discharge; less than half that of NiCad. Left uncharged, LiFePO4 cells can retain their charge for up to ten years. Higher cell voltage of LiFePO4 (3.6V) means fewer cells and associated connections and electronics are needed for high voltage batteries. One LiFePO4 cell can replace three NiCad or NiMH cells, which have a cell voltage of only 1.2 V. (110V NiCad = 87 to 91 links, LiFePO4 will have 33 or 34 links) LiFePO4 contain no liquid electrolyte which means they are immune from leaking. NiCad contain liquid potassium hydroxide which, if leaked, is extremely corrosive and so toxic it is fatal if ingested. NiCad cells contain cadmium which is a known carcinogen In higher discharge rate applications LiFePO4 can produce double the usable capacity of similarly rated NiCad batteries. Flat voltage discharge curve means maximum power available until fully discharged (no "voltage sag" as with NiCad batteries) LiFePO4 cells can deliver a very high discharge rate, 10C continuous, 20C pulse discharge LiFePO4 accept much higher charge rates - up to 3C = much faster recharging possibilities Unlike NiCad batteries, LiFePO4 can be left in a deep discharged state for extended periods without causing permanent reduction of battery capacity. LiFePO4 do not suffer from "thermal runaway" Can be used safely in high ambient temperatures, up to 65 oC without significant performance degradation. NiCad can only operate reliably at up to 35 to 40oC. LiFePO4 are 100% maintenance-free for the life of the battery. NiCad must be maintained (electrolyte checked and topped up) at least once every year, some NiCad manufacturers recommend maintenance once every six months. LiFePO4 can be operated in any orientation, including inverted LiFePO4 do not contain any toxic heavy metals such as lead, cadmium, nor any corrosive acids or alkalis. LiFePO4 batteries are the most environmentally friendly battery chemistry available today.  

LiFePO4 and other battery types compared

LiFePO4 and other industrial battery types compared