Hitachi Automotive Systems has developed a high-output 48-volt battery pack to improve the fuel efficiency of mild hybrid electric vehicles (mild HEVs) that use a battery and motor to provide power assistance when the vehicle is being driven by its internal combustion engine. A mild HEV is a technology for improving the fuel efficiency of passenger cars by using the power of a battery-driven motor to provide power assistance when the vehicle is being driven by gasoline power. The newly developed 48-volt lithium-ion battery pack is a highly integrated package that in addition to the BMS board and battery cells, includes a relay and fuse.
With excellent low-temperature characteristics and approximately 1.5 times the output density of Hitachi’s previous battery cells, it is a highly reliable battery pack that, with its high-output prismatic lithium-ion cells, when assisting the acceleration of a motor using a 48-volt system, delivers a fully sufficient torque performance for a maximum output of 10 kW or more and maximum input of 13kW or more (for 10 seconds in each case). The compact design of the battery pack helps to increase the degree of installation freedom in the passenger compartment. This summer, Hitachi Automotive Systems will start shipping samples to customer car manufacturers and aims to commence mass-production in fiscal 2018. With the expectation being for rapid future growth, Hitachi estimates that by 2023, HEV unit production will be over 2 million units in Europe and over 4 million units in China.
