Plug-in Hybrid Powertrain Technology
Honda strives to electrify two-thirds of global automobile unit sales in 2030.
Our development will put a central focus on hybrid-based models
utilizing a high-efficiency plug-in hybrid system unique to Honda.
Clarity Plug-In Hybrid (PHEV)
Honda's latest Plug-in Hybrid (PHEV) model is Clarity Plug-In Hybrid (PHEV) sold in U.S.A. since December 2017.
The Clarity Plug-In Hybrid utilizes Honda’s innovative two-motor hybrid technology, which consists of (1) an ultra-efficient 1.5-liter DOHC i-VTEC® Atkinson-cycle in-line 4-cylinder engine coupled to a starter/generator motor; (2) an ultra-quiet 181-horsepower AC synchronous traction motor; and (3) a 17-kilowatt hour (kWh), 168-cell lithium-ion battery pack.
The Clarity Plug-In Hybrid runs primarily on its electric motor, using its Atkinson-cycle engine and starter/generator motor to generate electricity that is either supplied directly to the traction motor or used to recharge the 17 kWh lithium-ion battery pack. An electric-servo brake system is deployed for regenerative braking, further improving efficiency by using the energy from deceleration and braking to generate additional electricity.
The Clarity Plug-In operates in three different driving modes, depending on the driving situation, and is able to shift instantly, automatically and seamlessly from one mode to another to optimize overall efficiency:
In EV Drive mode, the Clarity operates like an all-electric vehicle – the engine is off and is decoupled from the drivetrain to reduce friction. Motive power comes from the 181-horsepower traction motor, which draws electricity from the lithium-ion battery pack.
In Hybrid Drive mode, the Clarity functions as a series hybrid. Like EV Drive mode, motive power comes from the electric traction motor. The coupled gasoline engine and generator motor produce electricity, which is sent directly to the traction motor or to the battery pack, depending on the driving situation and the battery’s state of charge.
In Engine Drive mode, which is typically engaged when cruising at medium to high speeds, the Clarity funtions as a parallel hybrid. A lock-up clutch connects the engine (always linked to the generator motor) and the traction motor to send power directly from the engine to the front wheels. Unlike most competing hybrid and plug-in hybrid vehicles, the Clarity does not use a conventional transmission which saves weight and minimizes complexity while improving efficiency.
The Clarity Plug-in Hybrid also features three driver-selectable operating modes – Normal, Econ and Sport – allowing users to customize their driving experience, maximizing efficiency or driving performance. A fourth mode – HV mode – is provided to preserve the battery's state of charge and can be selected in conjunction with Normal, Econ and Sport driving mode.