Hitachi Automotive Systems supplying 5 kW/kg high power density prismatic Li-ion cells for MY 2016 Malibu Hybrid
Hitachi Automotive Systems, Ltd. will supply 5,000 W/kg high power density prismatic lithium-ion battery cells for the new MY 2016 Chevrolet Malibu Hybrid (earlier post). Featuring a new full-hybrid powertrain which leverages technology from the Chevrolet Volt, the 2016 Malibu Hybrid will offer an estimated combined fuel economy rating exceeding 45 mpg (5.22 l/100 km).
The Hitachi Li-ion cells employ heat resistant separators to ensure the ionic conductivity between the electrodes, achieving not only a high output power density of 5,000W/kg, but also a high level of safety. In addition to this, the battery’s ability to maintain its high output power density in GM evaluations, even under extremely low temperatures such as the -30 ˚C cold region test, led to its adoption.
Hitachi uses an NMC cathode paired with a hard carbon anode.
|Average Voltage (V)||3.7|
|Output Density (W/kg)||5,000|
|Energy Density (Wh/kg)||80|
The new cell is a modification of Hitachi’s 5.3 Ah prismatic cell, which featured a specific power of 3,400 W/kg and specific energy of 76 Wh/kg.
GM had earlier used Hitachi’s cylindrical 4.4 Ah Li-ion cell—a downsized and lightweighted version of the 5.5 Ah cylindrical cell in use in hybrid-electric trucks, buses and trains—in hybrid products. Those 4.4 Ah cylindrical cells had a specific power of 3,000 W/kg and specific energy of 61 Wh/kg.
Hitachi’s lithium-ion battery operations for vehicles began in 1999. To date, a total of more than 5 million lithium-ion batteries have been introduced into the market for commercial hybrid buses and trucks, as well as hybrid passenger cars.
Last year, Hitachi Automotive Systems integrated the lithium-ion battery manufacturer Hitachi Vehicle Energy’s design and R&D departments, advancing lithium-ion batteries by using the electronic, control, and software technology the company possessed toward battery control system development. (Earlier post.)