Matsushita Electric Industrial, best known for its Panasonic
brand, announced that one of its battery subsidiaries has established a
mass-production system for a lithium-ion battery that incorporates technologies to ensure safety. The company began shipping the industry’s first
2.9 Ah high capacity batteries for notebooks in April this year and is now ready
to mass production.
Matsushita representatives said the new design improved battery safety by forming a heat
resistance layer (HRL) consisting of an insulating metal oxide on the surface
of the electrodes. Lithium-ion batteries contain a thin plastic separator to
insulate the cathode from the anode. When a separator is pierced by an
electrically conductive material such as a metal particle, a short-circuit
develops, causing the battery to overheat and, in the worst case, catch fire.
The HRL used in the Panasonic battery, however, has better insulating and heat-resistant
characteristics than plastic. Even if a short-circuit occurs, it will cease
without causing the battery to overheat.
Prior to HRL, the company adopted stronger separators and
thermally stable materials to help guard against battery material contamination.
Matsushita said that HRL technology will ease development of lithium-ion batteries
to higher levels of capacity and safety.
Following the Sony laptop battery fiasco
of 2006, intense interest is paid to the safety of the portable energy source.
The IEEE is in the process of updating its standards
for laptop batteries, and some companies are starting to use the more stable lithium polymer battery