Your batteries are quite new, l would not worry.
lt is a bit annoying that Sony, has no indication on their cameras, about battery health, something else missing from Sony.
Sony batteries should last at least 5 years.
When I saw this thread this was my first thought to ask, what is the lifetime of a Sony battery. I got my camera about 5 years ago, but purchased 2 additional batteries about 3 years ago. My worst worry when traveling is the batteries dying and where I am going there is going to be no store (unless anyone knows of a shop in the middle of the desert or savannah).
You have a good about the camera displaying battery health. I am going to assume that the system should already be able to read something, just not displaying to the user. They must have some sensors or metrics that read everything from battery temp to stuff way beyond my technical understanding (just like some other devices do).
Longevity is measured in how often you cycle them (full discharge to full charge) and the operating temperature, which is the major killer of batteries. I charge my iPhone daily, but won't let it discharge completely, that means that if I charge it from 60 to 100% today, and tomorrow I do the same, I'll be completing one full cycle in 2 days and a half approximately. Li-ion batteries are expected to last 1,000 cycles and doing this routine, it should give me between 5 to 6 years of "expected" life.
I charge my camera batteries way WAY less frequent than my phone. So I believe they can last as much or longer.
When I'm not shooting, but still take my camera with me everywhere, as I usually do, even to work and visit customers, I might let a battery in the camera for the whole week, if I happen to just capture a few snapshots here and there, and still get over 60% by Friday. Then I'll put it in the charger and grab a fresh one.
For my shooting routine today is an example. I'm going to downtown LA in a couple hours, going to visit the Walt Disney concert hall, Union Station, Hollywood Blvd and Rodeo Drive, and I will grab some lunch in between those places. So once I'm sitting I'll swap my battery for a fresh one. The one I was using should have like 70%ish life left, but I won't let it go down completely, so I'll put it back in my Jupio and grab a fresh one.
It might not work for everyone, and also depends on the conditions but in general this is what I do, it works for me and batteries keep its performance longer.
