most likely they are overused. Lithium batts do not like to be deep-cycled(meaning running them to 3V) unlike NICAD batts, contrary to popular belief.
As a sidenote, NiMH should not be deep-cycled as well. Deep cycling causes substantial capacity drops.
As a sidenote, NiMH should not be deep-cycled as well. Deep cycling causes substantial capacity drops.
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