Civic Hybrid: IMA Electric Motor
Providing a supplemental power boost and giving the Civic Hybrid the capability to cruise on its electric motor alone in certain driving situations, the IMA's new, lighter and more powerful electric motor is designed to provide up to 23 additional horsepower (17 kW) to the Civic Hybrid's engine. Mounted between the engine and the CVT transmission, the IMA motor is an ultra-thin DC brushless design and provides a substantial amount of low-end torque to aid acceleration, while also assisting in steady-state cruising and hill climbing.
In addition to providing supplemental power, the IMA motor acts as a generator during deceleration and braking to recapture kinetic energy and recharge the IMA's battery pack during regenerative braking. For this fifth generation of IMA motor, an 8-pole design (instead of the previous 6-pole design) reduces heat. The new motor also operates in a lower voltage range (108-172V) compared to the previous motor (132-211V).
Civic Hybrid: IMA Intelligent Power Unit (IPU)
Power for the IMA system is controlled through the Civic Hybrid's Intelligent Power Unit. Located directly behind the rear seatback, the IPU consists of the Power Control Unit (PCU)— or the IMA's command center, a rechargeable lithium-ion battery module, and an integrated cooling unit.The Power Control Unit (PCU) electronically controls the flow of energy to and from the IMA's electric motor.
The battery pack stores electricity in a bank of lithium-ion cells. This bank of 40 individual 3.6-volt batteries stores up to 144 volts of electrical energy for the IMA motor. The new lithium-ion battery technology has approximately twice the energy density and about four times the output density of the previous nickel-metal-hydride batteries. Output is increased by 33 percent, volume is reduced by 36 percent, weight drops by 29 percent and the work capacity of the charging and discharging rates is approximately 3 times higher.