Slice Battery Capacity Preservation (Z22 and others)

I have a basic but important long term battery care question regarding the slice battery for my Z22, but it likely applies to all of the Sony slice batteries and beyond:

If I usually have this unit plugged in will the slice battery last longer if I leave it off? If the answer is yes, would it make much difference to its longevity if I store the slice battery in the refrigerator? Finally, would the answer change if I used, as I do, the Battery Care function set to 80%, or 50%?

Like most people, I would ideally like 100% of both batteries' reserves to be available whenever I need it, but there is clearly a tradeoff between keeping both batteries fully charged at all times and the long term capacities of the batteries. It's a pretty basic question, but one I expect most people are curious about, and not certain of the answers.

Thanks

 

If you plan to not use the slice for a at least a month, then put it in storage.
If it stays plugged in and you occasionally run on battery so that it discharges a little and u recharge it later, just keep it plugged in.
The battery care function is pretty much irrelevant in this context afaik.

 

Sony claims that stopping the charge at 80% reduces the rate at which the battery wears out; 50% reduces this rate even further, but 80% is a fair compromise. You are right that this is a trade-off, so just factor in how much the cost of a new battery will pinch you - if you are loaded I guess this won't matter a bit.

50% works for me - I seldom take unscheduled trips into the wilderness where I'll be without access to a power outlet. Many of our trains, and even some buses have power outlets for laptop and mobile chargers, so other than having to carry the adapter around, I don't find a downside to this. Whenever I expect to be without power, I turn off the battery care, charge to 100%, then go back to 50% when I get back.

 

It is not just Sony claims about their batteries.
It is the specifications of Li-Ion batteries and its preservation for battery wearing.

 

Thank you all for your input. From all that I'm hearing that my use patterns and need for both batteries to have at least 80% when I go off-AC without notice dictate that I should keep the slice on, charge to 80% and plan on replacing the slice every two years or so - actually, probably be ready to sell when this one goes below 75% or so of original capacity

Interesting thing: I got this battery used - but with 100% capacity. For 4 months I've had it connected almost all the time, set to 80% charge. Current capacity: 100%. Same with the internal battery, also bought used in the same purchase. Seems to me that once a battery starts losing capacity it goes down at a steady pace.