Diagrams representing voltage and worktime dependly from battery type, quality, temperature and screen brightness.
The cheapest battery found on the market: 0,2 €
Temperature of water: 15 degrees
Brightness level: medium
Battery measured out of computer
min. soft ver: 2.1
Total working time: 15h 15 min
Temperature of water: 22 degrees
Brightness level: high
Battery loaded at the computer
Total working time: 9h 15min
AA rechargable battery BP2700mAh
Total working time: 15h