I'm wondering if it is technically possible to track a SIM card inserted in a cell phone with sufficiently charge in the battery.
A SIM card only provides the device with a unique identifier and related information. It does not have any in-built wireless capabilities. In order for a mobile device to be tracked, it needs to be connected (or trying to connect) to a cell tower. Both receiving and transmitting non-negligible amounts of RF requires power to be provided by the battery. If the device is off then so is the transmitter, regardless of whether or not the battery has any remaining charge.