user: Question: How many volts has an energy-to-weight ratio of 54 kJ/kg to 2.0V?
Columns: ['Capacity', 'Volts', 'Temp.', 'Energy-to-weight ratio', 'Power-to-weight ratio']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['2000 F', '4.0V', '25°C', '54 kJ/kg to 2.0V', '44.4 W/kg @ 5A']
SQL:

assistant: SELECT "Volts" FROM "Table" WHERE "Energy-to-weight ratio" = '54 kJ/kg to 2.0V';