Denso Touts Improved Alternator Diode

Denso Corp. and partner Hitachi Power Semiconductor Device Ltd. have developed a new diode technology that they say can improve an alternator’s power generation efficiency by 6%.

Denso will begin producing alternators with the diodes later this year for vehicles sold in Europe. The new diodes can be used in existing alternator designs for gasoline and diesel engines.

Diodes help alternators convert power generated by the engine into electricity stored in a car’s battery and to power auxiliary components. An alternator typically has 12 diodes.

The new system’s improved efficiency is attributed to simplifying control functions and employing advanced manufacturing techniques. Improving the power generation efficiency reduces engine torque load and boosts fuel efficiency, Denso notes.

The supplier estimates that carbon dioxide emissions could be reduced by 30 tons if it used the more efficient diodes in all 25 million alternators that it produces every year.