Default Parasitic loads and "mini cycles" while charging (may) disrupt overcharge protection

So I was reading some articles on smartphone batteries and Li-ion batteries and read about parasitic loads can disrupt overcharge protection. I was wondering if this happens on the xperia z? Because I tend to charge the phone overnight along with "Smart Alarm" app which runs in the background tracking my sleep (it uses sensors such as gyroscope and microphone). Does this affect the overcharge protection? Because I heard if we charge overnight the battery is usually below 100% which is showing that it is preventing overcharge but every time I check its 100%

Info from a battery monitor app

My device is C6603 and on latest stock firmware with no modifications.

What do you guys think? I don't usually charge my device overnight before but since on the xperia z manual said it's okay so I give it a go
Asus TF300T Blue,
Recovery: TWRP

Xperia Z C6603 - Stock

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