"I had the laptop on mains without switching to battery all last week as I stayed at home and sleep was never failed once. As soon as I was on the move and started switching supplies again this week sleep instantly failed twice in two days."
Would it be true to say that the problem only occurs when the battery is fitted, and never when the battery is completely removed?
If so, then I would suspect some problem either with the battery itself, or with its connection to the computer.
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