For how long does the battery work?

We don’t measure the battery capacity by time, but rather by volume of warmed blood / fluids. The Warrior lite battery warms up to 1.3 liters of cold fluids/blood and up to 2.5 liters of room temperature fluids. If greater capacity is needed, consider using the Extra Power battery (3 liters of near-freezing blood / fluids and 5.0 liters of room temperature fluids). Fully charged batteries assumed. The system is optimized for the high-flow and low-input-temperature range.