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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).

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.

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.

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.