Noted at http://batteryuniversity.com/
About the only bad thing is to drain them. Also, a bad design is a bad design. If the maker cheaped out on the charger and charging circuits, not much can save it from the usual 300 some cycle death.
Bob
I've got a Sony Walkman which of course has a sealed battery and I want to get as many charge cycles out of it as posslble.
My Questions:
Should I recharge it as frequently as possible even if it is still at 75% capacity?
Is charging at a high capacity, e.g. 75%, "wasting" a charge cycle?
Should I instead wait until the battery level is reduced to no greater than 50% or 25% or so before charging?

Chowhound
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