OREANDA-NEWS. July 11, 2012. Furukawa Electric Co., Ltd. and Furukawa Automotive Systems Inc. (Head Office: 1,000 Amago, Koura-cho, Inukami-gun, Shiga Prefecture; President: Michitoyo Kurokawa) have jointly developed the world’s first vehicle-mounted lead battery status detector sensor equipped with a pulse discharging circuit. The sensor enables high-accuracy monitoring of the lead battery status even when the engine is turned off or on vehicles not equipped with a starter motor. This function is useful for preventing depletion of the battery.

Background of development

The internal resistance(note 1) of batteries is an extremely important index for understanding discharging performance and the degree of depletion.

Internal resistance has conventionally been calculated based on the electric current and voltage response when the engine (starter motor) is started, but this method does not allow the internal resistance of lead batteries to be measured when the engine is turned off or on electric vehicles (EVs) and hybrid electric vehicles (HEVs) not equipped with a starter motor.

Our company has developed the technologies to install a discharging circuit in the sensor, make pulse-form discharges at the timing of the sensor control, and calculate the internal resistance based on the electric current and voltage response at that time. The sensor enables, for the first time in the world, monitoring of the lead battery status even when the engine is turned off or on EVs and HEVs not equipped with a starter motor. Electro-chemical expertise on battery phenomena possessed by our group company The Furukawa Battery Co., Ltd. has been utilized for increasing accuracy for battery status monitoring technologies.