Apparatus and implementation of a battery in a non volatile memory subsystem
The battery apparatus introduced here provides a tool for reliably measuring the run time to empty of a battery used in a network storage server for protection of data during a failure mode. The battery run time to empty can be determined by a management controller based on battery information generated by a controller and received at the management controller. The information received at the management controller includes run time to empty, voltage, current and current battery capacity.
1. An apparatus comprising:
a battery to power a non-volatile memory in a network storage server;
a first controller coupled to the battery to generate battery information comprising a battery run-time-to-empty parameter, a battery voltage parameter, a battery current parameter, and a battery capacity parameter; and
a management controller coupled to the first controller to read the battery information from the first controller while the battery is under an artificial load, to determine a first remaining useable time of the battery based on the battery information, to determine a second remaining useable time of the battery based on the battery information, and to determine a status of the battery using the first remaining useable time and the second remaining usable time.
2. The apparatus of claim 1 , wherein the management controller calculates the remaining useable time of the battery based on an artificial load that approximates an actual load on the battery expected to occur during a power loss.
3. The apparatus of claim 1 , wherein the first controller is a gas-gauge integrated circuit.
4. The apparatus of claim 1 , wherein the battery is switchable to provide power to the non-volatile memory in the case of a loss of power from a main power supply of the storage server.
5. The apparatus of claim 1 , wherein the non-volatile memory is a non-volatile random access memory (NVRAM).
6. The apparatus of claim 1 , further comprising a protection device configured to provide protection for the battery for conditions of overcharge, overload, short circuit, overvoltage and undervoltage.
7. The apparatus of claim 6 , wherein the protection device is coupled to the first controller via a bus.