Li-ion batteries are now widely used as a staple for cell phones

Lithium ion batteries are widely used as a staple for mobile phones, laptops and some other gadgets. Its comfortable, lightweight and rechargeable nature makes it the ideal battery chemistry for these devices. Unfortunately, all these positive capabilities come with some significant drawbacks. The positive electrode or cathode, in these batteries is typically made of lithium cobalt oxide, which is http://d318.blog.com/ expensive and requires electronic circuitry to keep devices from overheating when charged. This also limits the size of the batteries. For these reasons, researchers began experimenting with new materials.

In 1997, researchers at the University of Texas at Austin proposed a new cathode made of lithium iron phosphate (LiFePO4). This material was cheaper and safer than lithium cobalt oxide, however, had a horribly low electronic conductivity.

In response, researchers have found a form of lithium iron phosphate with small amounts of metal plates. This molten material has a conductivity of 10 million times that of natural lithium iron phosphate, putting them on par with conventional cathode materials.

This cathode feed is the key ingredient in lithium phosphate batteries. Although this type of batteries are still in use, its high specifications show that will be very popular once they gain more exposure.
On another note, Lithium Technology Corp. announced in May 2007, the immediate availability of cells large enough for use in hybrid cars, claiming they are "the largest cells of their kind in the world" and that Toyota Prius runs on a battery of 125 MPG +.

This type of battery is also being used in the One Laptop per Child project.
As you can see, this chemical is on track to become an important part of the new technologies these days.

Advantages and disadvantages
Being a lithium ion chemistry resulting from the LiFePO4 chemistry shares many of the advantages and disadvantages of lithium ion laptop charger chemistry. fundamental differences are safety and current rating. Cost is claimed to be a difference but can not be verified until the cells are more widely accepted.

The lithium iron phosphate have some disadvantages. The ability of relationship between the size of LiFePO4 battery is somewhat lower than LiCoO2 battery. battery manufacturers worldwide are working to find a way to get maximum storage performance for smaller size and weight.

Security
LiFePO4 cathode material is inherently safer than LiCoO2 spinel and manganese. The Fe-PO bond is stronger than the Co-O bond so that when abused, (short circuit, overheating, etc) the oxygen atoms are much more difficult to remove. This stabilization of the redox energies also helps fast ion migration. Only under extreme heat (usually over 800 ° C) degradation to occur, which prevents the heat out of control that is prone to LiCoO2.

As lithium migrates out of LiCoO2 cathode in a cell, the CoO2 undergoes nonlinear expansion, which affects the structural integrity of the cell. The fully lithiated state unlithiated of LiFePO4 and are structurally similar, which means that the LiFePO4 cells are more structurally stable than LiCoO2 cells.

No lithium remains in the cathode of a fully charged cell LiFePO4 - in a LiCoO2 cell, approximately 50% remains in the cathode. LiFePO4 is very difficult for the loss of oxygen, which usually results in an exothermic reaction in other lithium cells.

The development of a safer cathode material can solve the problems that researchers have discovered while working for the manufacture of lithium ion batteries large, but this technique still needs more fine tuning chemicals before it can be used for commercial hybrid vehicles for food.