Why Body Battery is draining faster when starting with high level even with low stress?

When i start the day with high body battery level (>75) it always drains quite fast dropping to 60 in the first two hours or so, even with low stress levels. But when I start the day with battery around 50 only, it drains very slowly even with the same activities and stress levels during the day. In both cases and very comparable days I end up around 25-25 in the evening. How comes? Why this faster drain when Body Battery is high?

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Nirtsuk 18 days ago +1

I noticed the same effect. I am curious why there are no official answers to this question. I assume that the reason lies in the algorithm. Probably, the same level of stress depletes the same percentage…

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0 7338931 4 months ago

I have the exact same thing, no idea what causes it. I think its the watch realizing it made a mistake in the sleep scoring and adjusting throughout the day by draining the body battery less until it gets to the level it was supossed to be at with a correct sleep scoring.

0 Nirtsuk 18 days ago

I noticed the same effect. I am curious why there are no official answers to this question. I assume that the reason lies in the algorithm. Probably, the same level of stress depletes the same percentage of current battery level. For example, if battery is 90% full, 10% depletion is 9% but if the battery is 30%, 10% depletion is only 3%. This method slows down the depletion of body battery at low levels and prevents it to reach negative values. Garmin even imposed the limitation of 5% which is the lowest value the battery can have. This is my own reasoning and not necessary true.

0 6699490 18 days ago in reply to Nirtsuk

That makes a lot of sense and sounds reasonable. We still have no official explanation and it's hard to verify when remaining BB in the evening is different from day to day. But for days where the battery hits 5% it would at least align well. I have such days occasionally with basically the same activities of work and training. The biggest difference is the starting BB%. When it reaches 5 in the evening, it does so almost at the same time, no matter if it started at 90% or at 50%.
(if it started at 30% I would skip the training session, which is then not the same anymore).

0 Nirtsuk 7 days ago in reply to Nirtsuk

My observation regarding 5% lowest level limitation for body battery. Although body battery display remains at 5%, the background algorithm seems to keep recording further battery depletion. Why do I think so? Example: Yesterday, my battery level dropped to 5% at 20pm. After that, I was still being active for another two hours. Further battery depletion must have happened before my bed time. After falling asleep, the battery display remained at 5% for two hours before starting to charge again. My guess is that during those two noncharging hours, the battery level was actually recovering from the level which was lower than 5% although the displayed level never dropped below 5%. Any similar observations?