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Recent electric vehicles use Li-ion batteries to power the main electric motor. To maintain the safety of the main electric motor battery using Li-ion cells, it is necessary to monitor the voltage of each cell. DENSO has developed a battery Electronic Control Unit (ECU) that contributes greatly to the reduction of the cost and the improvement of the reliability of the system. Each manufacturer has been developing a dedicated IC for monitoring the voltages of each cell of a battery. However, since the number of cells that can be monitored is limited, more than one IC is required to measure the voltages of a large number of cells. The increase in the number of ICs and the amount of insulator leads to the rise in system cost. DENSO has developed a dedicated IC that uses a proprietary high-breakdown voltage process, and which enables monitoring up to 24 cells with a single IC chip.

Experimental investigations of intake and exhaust valve timing effects at part load have been carried out on a 4 cylinder, 1.6 l spark ignition engine. The effects of valve timing on charge dilution by residual gases, and on fuel consumption and emission characteristics, have been explored. The valve timings, and particularly the duration of the valve overlap period, strongly influence levels of charge dilution. The extent to which this accounts for the observed changes in specific fuel consumption and emissions with valve timings is investigated. Residuals gas fraction values have been determined at various steady operating conditions through the analysis of gas samples drawn from the cylinder near the tip of the spark plug. A gasoline direct injection fuel injector operating in reverse flow was used as a high-speed sampling valve. Brake specific values reflect a combination of changes in dilution and, at different brake loads, changes in pumping work.