battery routine question - primary and li-ion

Do you have a battery routine? lol or should I saw what is your routine.

i.e.

Only fully charged li-ions go in lights that are to be used. Used batteries get charge up to near 50 percent, then stored. Or you can use the same battery. ^ does that make sense?

Check primary batteries every now and then (two CR123A cell Surefires). Question: should they match on a ZTS meter? Would it be problematic if one was 30 percent and the other 60 percent?

I used to be quite anal about battery management. Now, I try to balance that with practicality.

NiMH Eneloops get charged up fully whenever I use them more than just a little bit. All my AA/AAA lights have fully-charged cells in them. I cycle them out with spares, so I never have to wait to charge them up when I replace them in my lights. The ones in storage are fully-charged, too. Makes things easy, and Eneloops don't suffer much from being 100% charged all the time.

Lithium-ions, I'm a little more conservative. Generally, I keep fully-charged cells in my lights that I used most. They get charged whenever I've used them enough to drain them down to around 75%. That's around 3.9v for most brands of cells. It might be healthier for the cells if I let them drain down to 20% or 30% before recharging, but that makes the light less useful to use if I want to use it for awhile.

Cells in short-term storage, which I use mainly as spares for easy-swapping of batteries, usually get stored at 4.1v, which is about 90% charged. It's a good compromise between health of the cell and usefulness of the cell. They might sit that way for a month or two, depending on how much I'm using my lights. When I swap them into my lights, I won't bother topping them up to 4.2v. 90% is good-enough.

Cells in long-term storage (i.e., a year or more), get stored at 3.75v, which is about 50%. Best for the health of the cell, and I'll charge them up fully before I use them.

Thanks WalkIntoTheLight.