I wud say that it wud be cheaper just to buy the higher-voltage LIPO battery

As River Rat has said you need a boost converter. That said the raised voltage will not have a current capacity of 5.5 amps. Just had a quick look on line and there are some that claim 4 amp max but I would not like to try using it at that level. On Amazon "Boost Converter Module XL6009E1 DC to DC 3-32 V to 5-35 V Output Voltage Adjustable Step-up Circuit Board". I would be happy running it at say 2amps for auxiliary items.
dave976

You need a boost converter. A buck converter steps down voltage. 👍