need physically Small power supply from high DC voltage

I have experience from 48 volt heavy traction lead battories. 6, 12 and 24 starter battories are also common but battories close to 85 volt is new to me. There are some 120 volt fork lift trucks and some with a voltage lower than 100 due to EU regulations.
What kind of things are You using? Where are they used etc.? Why this 85 volt?