Hitachi, Ltd. earlier this week announced that in conjunction with Hitachi Vehicle Energy, Ltd. which develops and manufactures lithium-ion batteries for automotive applications, such as hybrid electric vehicles, it has developed a lithium-ion battery. According to the company the battery has the world's highest power density of 4,500 W/kg, 1.7 times the output of the company's mass-produced, automotive lithium-ion batteries.
Sampling of the new battery by domestic and overseas car manufacturers will start in the fall.
To reduce internal resistance, the battery employs a new manganese cathode and an original Hitachi battery structure, such as thinner electrodes, power collection method and effective configurations.
In recent years, lithium-ion batteries have been used for consumer product applications, including mobile telephones, notebook PCs and digital cameras. For the same energy density, a lithium-ion battery has about half the volume and weight of a nickel hydrogen battery, and about one-third the volume and weight of a lead battery. This makes the lithium-ion battery a small, light, high-energy-density secondary battery that is attracting attention for its applicability to hybrid and electric vehicles.
In 2000, the Hitachi Group used its manufacturing capabilities in fields ranging from materials to battery control systems, to develop and mass-produce the world's first safe, high-performance, long-operating-life lithium-ion battery for automotive applications.
A second-generation lithium-ion battery with an power density of 2,600 W/kg that currently is being delivered for automotive and railway applications. Up to this point, a total of some 600,000 cells have been delivered, mainly to car manufacturers and railway companies.
Moreover, development of a third-generation lithium-ion battery having an even higher power density (3,000 W/kg) has already been completed, and will go into mass-production in 2010, with deliveries scheduled to begin the same year.
Going forward the company says it will providie optimal battery system solutions that include control systems.