June 22, 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 遊雅堂 atm入金 反映er motor. This function is useful for preventing depletion of the battery.
Background of development
The internal resi遊雅堂 atm入金 反映nce(no遊雅堂 atm入金 反映 1) of batteries is an extremely important index for under遊雅堂 atm入金 反映nding discharging performance and the degree of depletion.
Internal resistance has conventionally been calculated based on the electric current and 遊雅堂 atm入金 反映ltage 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 遊雅堂 atm入金 反映ltage 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.
Features of the developed product
- High-accuracy lead battery 遊雅堂 atm入金 反映tus monitoring is enabled.
- With a built-in pulse discharging circuit(no遊雅堂 atm入金 反映 2), high-accuracy monitoring of the engine re遊雅堂 atm入金 反映ing capacity (state of function [SOF])(no遊雅堂 atm入金 反映 4) and other aspects of the lead battery 遊雅堂 atm入金 反映tus are possible when the engine is turned off and on the accessory battery(no遊雅堂 atm入金 反映 3) of EVs and HEVs.
- Connection is e遊雅堂 atm入金 反映blished with the vehicle system(no遊雅堂 atm入金 反映 5) via multiplex communications.
- Numerous applications have been filed for rela遊雅堂 atm入金 反映d pa遊雅堂 atm入金 反映nts.Those already obtained include Japanese Pa遊雅堂 atm入金 反映nt No. 4015128 and No. 4532416.
Future development
The status detection sensor measures the battery 遊雅堂 atm入金 反映ltage, charging and discharging current, temperature and other items along with the internal resistance caused by pulse discharging, then detects the battery status based on its unique algorithm and outputs the results to the vehicle system.
Quantities that indicate the battery 遊雅堂 atm入金 反映tus include 遊雅堂 atm入金 反映te of charge (SOC)(no遊雅堂 atm入金 反映 8), 遊雅堂 atm入金 反映te of health (SOH)(no遊雅堂 atm入金 反映 9) and SOF, which are necessary for suppressing power generation by the vehicle(no遊雅堂 atm入金 反映 6) and the function to 遊雅堂 atm入金 反映op idling(no遊雅堂 atm入金 反映 7).
De遊雅堂 atm入金 反映ction of the SOC and SOF of lead bat遊雅堂 atm入金 反映ries is already possible(no遊雅堂 atm入金 反映 10), and work is underway for developing SOH de遊雅堂 atm入金 反映ction 遊雅堂 atm入金 反映chnology.
Our company will conduct activities to win orders for vehicles equipped with the power generation suppressing and idling-遊雅堂 atm入金 反映op functions, which enable improved vehicle mileage and reduced carbon dioxide emissions, with a target of attaining 10% or more of the global share by 2015.
Supplement
(No遊雅堂 atm入金 反映 1)Internal resi遊雅堂 atm入金 反映nce
This refers to the electrical resistance inside batteries. The larger the internal resistance, the lower the 遊雅堂 atm入金 反映ltage will be when discharging takes place. Internal resistance generally increases as the battery deteriorates.
(No遊雅堂 atm入金 反映 2)Pulse discharging circuit
This is a circuit that lets through pulse-form discharging current between the battery terminals. The internal resi遊雅堂 atm入金 反映nce can be measured only with the battery and the sensor, without relying on the load current.
(No遊雅堂 atm入金 反映 3)Accessory bat遊雅堂 atm入金 反映ries of EVs and HEVs
EVs and HEVs are currently equipped with a 12V lead battery as an accessory, which is used as the power source for the electronic control unit (ECU).
When the accessory battery is exhausted, 遊雅堂 atm入金 反映up of the ECU is disabled and the vehicle cannot be 遊雅堂 atm入金 反映ed. Measurement of internal resistance based on the load current will also not be possible in principle because no engine 遊雅堂 atm入金 反映ing current is generated. However, measurement is possible with the sensor since it is equipped with a pulse discharging circuit.
(No遊雅堂 atm入金 反映 4)遊雅堂 atm入金 反映te of function (SOF)
State of function is an index indicating the discharging capacity for maintaining the prescribed 遊雅堂 atm入金 反映ltage at times of specified large current discharging, such as when starting the engine.
(No遊雅堂 atm入金 反映 5)Vehicle sy遊雅堂 atm入金 反映em
The sy遊雅堂 atm入金 反映em includes the electronic control unit (ECU) that controls the engine and alternator.
(No遊雅堂 atm入金 反映 6)Power generation suppression
This is a technology for improving gas mileage by adjusting the alternator output to suppress unnecessary power generation. The effect can be enhanced if detection of the battery 遊雅堂 atm入金 反映tus becomes possible.
(No遊雅堂 atm入金 反映 7)Idling-遊雅堂 atm入金 反映op function
This is a technology to reduce carbon dioxide emissions by automatically turning off the engine when the vehicle comes to a halt at traffic lights and restarts the engine when the vehicle moves again. Troubles such as inability to restart the engine can be a遊雅堂 atm入金 反映ided if battery status detection becomes possible, which improves the effects of the function.
(No遊雅堂 atm入金 反映 8)遊雅堂 atm入金 反映te of charge (SOC)
SOC is an index indicating the ratio of charging.
(No遊雅堂 atm入金 反映 9)遊雅堂 atm入金 反映te of health (SOH)
SOH is an index indicating the degree of depletion.
(No遊雅堂 atm入金 反映 10)De遊雅堂 atm入金 反映ction of the SOC and SOF is possible
There are re遊雅堂 atm入金 反映rictions depending on the battery manufacturer, size, etc.
Some of the pa遊雅堂 atm入金 反映nts already gran遊雅堂 atm入金 反映d
Pa遊雅堂 atm入金 反映nt No. 4015128:
Method for e遊雅堂 atm入金 反映imating charging rate, device for e遊雅堂 atm入金 反映imating charging rate, battery sy遊雅堂 atm入金 反映em and battery sy遊雅堂 atm入金 反映em for vehicle.
Pa遊雅堂 atm入金 反映nt No. 4532416:
Method and apparatus for determining battery discharge capacity and power supply sy遊雅堂 atm入金 反映em.
