VS - Electrical Systems From Stop-Start to Hybridization

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The battery sensor performs highly accurate synchronized current and voltage measurements, in both the charge and discharge phases, at precisely timed intervals. Battery temperature measurements are also to be recorded. The battery is monitored continually over its operational life including when the vehicle is parked. At the heart of the sensor is a current sensor and a programmable microcontroller that contains the State-of-Charge and State-of-Health algorithms. Since the sensed current can vary over a wide range from μAmps to hundred Amps, a high-resolution analogue to digital conversion circuit is required. Several modes The battery sensor microcontroller manages several working modes: ●● Sleep mode to minimize the drain on the battery when the vehicle is parked for long periods Monitor battery activity

In conventional vehicles, the battery is charged by the alternator, whether the car is on a highway or idling in traffic jams. ●● Battery is basically kept near to full charge in normal conditions ●● Battery can be subjected to high temperatures leading to corrosion ●● Sulfation can appear but it is not the lifetime driver In Stop-Start vehicles, battery is discharged and can be left in a discharged state for a few days ●● Battery state of charge can be dramatically degraded if nothing is done to protect the battery ●● Major Corrosion and sulfation phenomenon can strongly impact the battery lifetime To secure the battery lifetime and thus the board net energy level, the battery activity must be monitored, this feature is not new but it is a mandatory for all Stop-Start system. The battery sensor The battery sensor is an important part of the battery management system; it is mounted directly at the negative pole of the battery and is able to sense battery voltage, battery current and battery internal temperature through the negative pole thermal conduction.

●● Wake-up mode for cranking detection ●● Tracking mode - to evaluate the battery condition ●● Auto wake-up mode to take periodic measurements

The battery sensor generally communicates digitally to ECU’s via a Lin ( L ocal I nterconnect N etwork) communication bus.

The battery sensor monitors the battery state of charge; it integrates a voltage sensor, a current sensor and a temperature probe.

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