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Lithium-rich layered oxide, expressed as xLi2MnO3-(1-x) LiMO2 (M = Ni, Co, Mn, etc.), exhibits a high discharge capacity of 200 mAh/g or more and a high discharge voltage at a charge of 4.5 V or more. Some existing reports on cathode materials state that lithium-rich layered oxide is currently the most promising candidate as an active material for high-energy-density lithium-ion cells, but there are few reports on the degradation mechanism. Therefore, this study created a prototype cell using a lithium-rich layered cathode and a graphite anode, and analyzed the degradation mechanism due to charge and discharge. In order to investigate the causes of degradation, changes in the bulk structure and surface structure of the active material were analyzed using high-resolution X-ray diffraction (HRXRD), a transmission electron microscope (TEM), X-ray absorption fine structure (XAFS), and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM-EDX).

A new DC brushless motor, which has an almost equivalent driving performance to a 50 cm₃ scooter engine, has been developed to be used in a new electric motorcycle for business. The traction motor is compact enough to be mounted close to the driveshaft of the transmission, which helps reduce friction in the drive train. Consequently, in the downsized motor, by mounting the drive train unit with the PDU (Power Drive Unit) on the wheel side by applying reduction gears, it enables the reduction of maximum motor torque requirement. It also enables other parts of the drive system to be integrated into one unit. In this motor, IPM (Interior Permanent Magnet) structure has been implemented to cope with the high rotation of the motor, and the concentrated winding stator coil has been implemented for downsizing. As for the rotor, the magnets were placed in sections and the yoke shapes were improved to achieve higher rotation speeds that provide the higher power.

A new electric power steering (EPS) was developed which uses an electric motor to provide assistance. It is a system combinning the latest in power electronics and high power motor technologies. The development was aimed at enhancing the existing hydraulic power steering's energy efficiency, driver comfort as well as increasing active stability. This paper describies the overall concept of EPS and outlines the components and control strategies using electronics. The EPS was tested on a front wheel drive vehicle weighing 1000kg in front axle load. The results showed a 5.5% improvement in fuel economy. The EPS has also achieved returnability that gives the driver more moderate feelings matching the vehicle in action as well as the active stability control strategy for high speed driving.

An Integrated Motor Assist (IMA) system for the 2006 Civic Hybrid has been developed, with the goal of having class leading fuel economy among compact vehicles and enhanced driving performance. The IMA system has been enhanced for greater power and efficiency. Combining the 3-stage i-VTEC engine with a higher power, higher efficiency electric motor assist mechanism enables an increase in deceleration regeneration energy and a drive mode powered by the electric motor alone. The engine is a newly developed 3-stage i-VTEC, based on the 1.3L SOHC i-DSI engine. The new 3-stage i-VTEC engine incorporates both a VTEC mechanism that switches cam profiles in low and high engine speed ranges, and a cylinder deactivation mechanism. The CVT has both an expanded ratio range and a higher final gear ratio. Through these technological enhancements, we have achieved the highest levels of fuel economy in the compact class and enhanced acceleration performance.

A hybrid system combining a 4-stroke, 50cc-gasoline-engine with an electric motor was developed, and the maximum vehicle speed achieved by the electric motor is 30 km/h. Either an electric motor or engine is selected as the power source according to the running condition, and it is switched automatically. A parallel hybrid system, the Modulated Hybrid System (MHS), was adopted. Therefore, the energy source of the electric motor can be charged by an external or an internal power source. The switch mechanism of the driving power source is simple by using a one-way-clutch. The driving force, the vehicle speed, and the remaining battery energy are the parameters for switching control of the driving power sources. In order to achieve smooth switching and quick responses, the electric motor output is controlled by the feedback of the driving torque.

Honda has developed a powertrain for 2013 subcompact class EVs. This powertrain has both high power and low loss in order to provide the EV with better marketability than existing EVs, with the world-best energy efficiency and class-exceeding dynamic performance. To achieve the energy efficiency, this powertrain also has a function of cooperative control with a newly developed electrically operated servo brake system. To achieve the high dynamic performance, a new rotor shape has been introduced to the electric motor, and the power control unit (PCU) is equipped with a high thermal conductivity heat sink. The battery system allows high output power in a compact structure because of a triple parallel module group configuration and an air-cooling system. As a result of these innovations in the powertrain, the vehicle attains 82 miles of driving range while achieving world-leading energy efficiency of 29kWh/100 miles.

The Integrated Motor Assist (IMA) Hybrid Electric Vehicle (HEV) technology used in Civic Hybrid or Insight is developed originally by Honda, and is mounted in a V6 Accord with the aim of enhancing fuel economy of a mid-size passenger car. The development goal was to realize a mid-size passenger car that provides acceleration performance superior to a V6 Accord and the fuel economy of a compact class vehicle. Various means are employed to achieve high torque and high efficiency simultaneously, including an Interior Permanent Magnet (IPM) type rotor, low-loss electrical steel sheets as the stator material, and high maximum energy product magnets. These technologies increase the maximum power of the newly developed motor by approximately 20%, the maximum torque by 26% and motor efficiency over all ranges by approximately 1% to 3% compared to the current Civic Hybrid motor. Consequently, the maximum motor power of 14 kW and maximum motor torque of 136 Nm are achieved.

A motor-assist system has been developed and employed for the "Insight' hybrid car. The system consists of an internal combustion engine as the primary power source, with an electric motor placed around the engine's crankshaft. Such construction reduces the system's volume significantly and offers more flexibility for the power plant layout. The system's functions include regeneration during braking, an idle stop mechanism, driving power assistance, and power supply for the 12V electrical system. A proper energy management method for various driving modes has been established by combining these functions, and fuel economy is significantly improved as a result. As another control feature, an active motor vibration control system compensates the idling vibration that is unique to three-cylinder engines.

In recent years, an increase in vehicle weight due to the electrification of automobiles, specifically EVs, has increased the input loads on anti-vibration rubber parts. Moreover, the characteristics of these loads have also changed due to the rotational drive of electric motors, regenerative braking, and other factors. When designing a vehicle, in advance it is necessary to set specifications that take into account the spring characteristics and durability of the anti-vibration rubber parts in order to meet functional requirements. In this study, the hyperelastic and fatigue characteristics (S-N diagram and Haigh diagram) of Rubbers which is widely used for anti-vibration rubber parts, were experimentally obtained, and structural and fatigue analyses using FEM (Finite Element Method) were conducted in conjunction with spring and fatigue tests of anti-vibration rubber parts to determine the correlation between their spring and fatigue characteristics.

The development of Li-ion battery performance in next ten years will encourage improving a power density of Electric Vehicles (EVs). A higher voltage system with a boost voltage converter is favorable for the EV system if the converter has large power in small size. For increasing the converter power density, interleaved topologies using close-coupled inductors are shown to be superior. The inductor set of 3-phase type is proved to be smaller in size and lose less power in comparison to that of 2-phase type for high powered EV system having a 200∼400 volt battery. The prototype 3- phase converter using IGBT with 15 kHz switching frequency achieved a power density of 21.4 kW/liter at 120 kW output on a boost ratio of 1.38 with 98.0% efficiency, which also achieved more than 97% efficiency in a frequent usage zone.

Compared to conventional hybrid electric vehicles, plug-in hybrid vehicles have a larger-capacity battery and an onboard charger. These devices are mounted in functionally optimal locations, so it is a challenge to provide a thermal management system that achieves a good balance between high cooling performance and low cost. The battery should be operated at required temperature to secure safety and durability at high temperatures, and to mitigate the decrease in output power and capacity. However, setting separate cooling systems suited for each device leads to both an increased cost and weight. Therefore, an integrated water cooling system was devised for the battery, charger, and DC-DC converter, and the cooling performance was verified through simulations and tests. A valve installed before the battery in the cooling circuit allows it to be bypassed when coolant temperature rises due the charger or low-speed engine operation, helping to preserve battery life.

The idea to monitor the combustion in an internal combustion engine and using the obtained data to control combustion in the engine has been around for some time now. There are two well-known methods, although in the capacity of lab experiments, which had been developed under this principle. One features the analysis of combustion pressure and the other features the analysis of ionic currents detected in the combustion gas. Although highly precise analysis can be achieved by the former, there are problems in the installation of sensors for detecting combustion pressure, also in the durability and cost of such sensors. As for the latter, there are also problems in installing sensors for detecting the ionic currents and the reliability of obtained data from such sensors is still questionable.