AT&T Inc is replacing 17,000 backup batteries used as backup power sources in its outdoor telecommunications equipment cabinets. They are mostly used in equipment which is part of its U-verse television network. The company has decided to take action after two fires and two explosions which were apparently caused by the Lithium-metal-polymer batteries.

The batteries were allegedly manufactured by Avestor, which used a special metallic Li as the anode in the batteries, thus the Lithium-metal-polymer name for this innovative but less safe technology. However, the Quebec company went bankrupt in October 2006 and has since closed.

"Normally, we would work with a vendor to diagnose problems and develop solutions," AT&T said in a statement. "We can't do that in this case."

This is only a small fraction of AT&T's backup batteries installed in network equipment nationwide. The company said that it has about 400,000 backup batteries.

Following two Houston incidents, AT&T hired a leading scientific consulting firm, Exponent, to investigate the cause of an October 2006 equipment cabinet explosion and another January 2007 equipment fire. Strangely enough, Exponent concluded that the problems were caused by manufacturing defects, that the battery's safety features and overall design were "sound," and "concluded that the risk of hazardous failures with this battery is as low, if not lower, than the risk with alternative batteries."

However, following the report, two more dangerous incidents occurred later in 2007.

AT&T U-verse, the service which was powered up using cabinets containing the dangerous batteries, is the name given by AT&T to a group of services provided through Internet Protocol (IP), including television service, Internet access, and eventually voice telephone service.