So I’ve read that it you’re not going to use the battery for a while it should be kept around 80-86v, is that right?
Is there a battery maintainer that can be purchased to make sure the battery stays at the right voltage for a few months of non-use?
Or is this not really necessary?
No battery maintainer should be necessary for a few months of storage.
Lithium batteries happily hold their charge at half-ish power. I have RC grade LiPos that have sat for a year and perform just fine when I dust them off again if they were first put in storage charge. Never leave lithium batteries fully charged or completely drained.