You should be able to get by with a much smaller battery. Thales tables are battery powered with a pack that looks like 4 or 5 AA batteries. This is their description: The outstanding feature of the TTT-Slim II is the battery based power supply with Li-Ion
accumulators. The peak capacity is higher than 100 W while using not one single vibrating element. Therefore it is possible to integrate the power-supply into the main chassis, keep the signal-path short and skip any connection to the power plant. The battery service life is 20 hours
accumulators. The peak capacity is higher than 100 W while using not one single vibrating element. Therefore it is possible to integrate the power-supply into the main chassis, keep the signal-path short and skip any connection to the power plant. The battery service life is 20 hours