A lithium iron battery, also known as a lithium ion batteries, is one that uses iron-phosphate (LiFePO4) for the anode material. First, let's understand what a LiFePo4 is in order to better appreciate the benefits.

Lithium-ion battery (or simply "Lithium batteries") are batteries that contain lithium based material as the cathode, and various other materials (mostly graphite) for the anode. Due to their light weight, small size and long battery life, these batteries are common in portable devices like cellphones and digital cameras.

Lithium is the most easily oxidized element, so lithium batteries are an advantage. It can also give up an electron which is used by the circuit for power. It is known that the battery lasts longer if it has more electrons available. Additionally, lithium is lightest known metal. This allows for portability, and it can be easily shaped.

Since lithium is reactive enough to form a salt in the environment, it can't be used by itself as a cathode. This is evident in the fact that lithium can't be found in either its elemental or native forms in nature. Lithium chloride and other halide salts are more common. Native lithium reacts with water and can even ignite, so its storage needs to be under oil.

In order to make lithium cathode, lithium compounds must also be used. For it to be rechargeable, the compounds must create ions upon decomposition.

One example of a common lithium compound is lithium ironphosphate (LI). LI batteries were invented at the University of Texas as a cheap method to create lithium batteries in 1996. It is affordable because lithium's partner, iron, is more plentiful than other metals that are used to make lithium compounds. It has the advantage that lithium batteries have a slower rate of discharge, which leads to a longer shelf-life.

As you can see, the reaction produces lithiumions and iron phosphates (FePO4). Ferric phosphate, or iron (III), is not toxic. This is in contrast to the iron (II), phosphate (Fe3 (PO4)). Ferric phosphate has been used in iron supplements for humans. It is therefore safe for human consumption.

This is the main reason lithium iron phosphate has been chosen over other lithium-based battery options. Other lithium-ion batteries such as the less common lithium cobalt batteries produce more toxic cobaltoxid compounds.