As my laptop battery cannot be removed I thought of this....
Recently I heard a scientist working on lithium ion battery technology describe how a rechargeable battery functions.
Think of it as a sandwich with a covering layer of chemicals with other chemicals in the center. When recharging the center goes through chemical changes to recharge. During this process the chemicals jiggle about so that the outer layer and the middle layer get disturbed and gradually get mixed which decreases the recharging capability. So the greater number of recharges the great mixing of the the chemicals reducing the recharging life.
Although this wasn't mentioned I thought that if one had the battery charge always at 100% or near ( if at a mains supply mostly) then the constant repetitive charging would not always do that destructive 'jiggling' mixing of the chemicals so prolonging battery life.
This is so obvious if true that as it has not been widely known I must be wrong - can anyone put me right please?