Hitachi Maxell to Introduce Li-ion Battery Using Silicon-based Anode Material

News reports reveal that Hitachi Maxell Ltd. will start shipping its lithium-ion (Li-ion) rechargeable battery using a silicon-based negative-electrode material in June 2010. As a first phase, prismatic cells will be released for smart phones. Hitachi has yet to disclose the names of customers or the capacities of the cells.

Hitachi developed the nano-silicon composite material created by dispersing nanoparticles of silicon grains in amorphous oxide silicon (SiO). The amorphous SiO mitigates the distention and contraction of silicon on charging and discharging. In practice, the SiO grains are coated with carbon to enhance their conductivity, and are also mixed with graphite.

According to Hitachi, the negative-electrode material’s discharge capacity per weight is said to be 20% higher than that of an existing negative-electrode material using only graphite. Furthermore, its charge-discharge properties for large current are high, which is said to reduce the charging time by more than 30%.

The company said it has 55 patent applications on the technology.