The maximum output voltage of the MAX17220 is 5V. The output voltage is determined by the resistance between SEL pin and ground. The table showing the relationship between output voltage and resistor selection is provided on page 14 of the datasheet (Rev 3 7/17) and is also included below. Even when SEL pin is shorted to ground, it can only reach 5V. Therefore, the output voltage of the MAX17220 cannot go above 5V.