Methods and systems for auto-calibrated power metering in portable information handling systems

A method for auto-calibrating and determining power usage information for a portable information handling system, comprising:

• providing a portable information handling system with a battery, a charger, and an AC/DC adapter;
• performing a calibration step when the portable information handling system is powered down and the battery is being charged through the AC/DC adapter, wherein the calibration step comprises using a battery charge meter within the battery back to calibrate an input power meter associated with the AC/DC adapter;
• and
• using the calibrated input power meter to determine power usage for the portable information handling system when the portable information handling system is powered on and operating using power provided through the AC/DC adapter.

A portable information handling system having an auto-calibrated power usage meter, comprising:

• an AC/DC adapter;
• a charger coupled to the AC/DC adapter, the charger having an input power meter;
• a battery coupled to the charger, the battery having a battery charge meter;
• and
• control circuitry configured to use measurements from the battery charge meter to calibrate the input power meter when the portable information handling system is powered down and the battery is being charged through the AC/DC adapter.