Battery: Description and Operation
Vehicle electrical system / Energy management
AGM (Absorbed Glass Mat) technology
A 12 V 92 Ah 520 A AGM battery is used in the Cayenne; a 12 V 105 Ah 580 A AGM battery is optionally available for colder regions. The battery is located under the left seat in the direction of travel.
The battery is based on AGM (Absorbed Glass Mat) technology. Special micro glass fiber mats lie between the lead plates of the battery and contain all of the battery acid. The absorbing capacity of the glass fiber mats is designed so that although the acid is completely absorbed by the matting, the degree of saturation of the matting is not reached. The sealed system is equipped with a pressure relief valve for the safe discharge of any gases.
The battery remains leak-proof and dry. Expanding liquid due to frost cannot cause any damage. Furthermore, by packaging the plates in micro glass fiber mats there is virtually no further movement of the plates, which means that vibration has no effect on the battery.
The entire electrolyte is bound by the acid in the matting, which means that there is no need for the maintenance tasks of filling with water and inspecting the electrolyte. AGM batteries are designed with an extremely low internal resistance, resulting in a faster reaction between the acid and the plate material. Higher energy quantities can therefore be produced even in demanding situations such as charging in extreme cold.
Battery replacement must be communicated to the gateway using PIWIS Diagnosis Tester II, specifying the (A) serial number/(B) part number/manufacturer and the battery size under Maintenance/Battery replacement. For charging, a charger with at least 40 A should be connected.
For jump-lead starting, a jump lead should only be connected directly to the external power supply connections in the engine compartment, as otherwise the battery sensor could be damaged and incorrect information (battery charging directly at the battery sensor) forwarded to the gateway.
Battery sensor
NOTE: Caution when jump-lead starting: Always connect the charging cable/jump leads directly in the engine compartment as otherwise the battery sensor could be damaged.
The battery sensor is located on the negative terminal of the battery, it is part of the energy management system (battery management). The battery sensor is connected between the negative terminal of the battery and the ground cable.
The purpose of measuring the battery size is to determine the battery condition with sufficient accuracy and to identify closed-circuit current faults in vehicle electrical system diagnosis in production and service.
The following measured variables are measured directly by the sensor
- Battery current
- Battery voltage
- Measurement of the temperature at the negative terminal
The battery current and battery voltage are measured simultaneously.