You can play a lot with your lights even at the voltage 3.7v-3.8v.
Keeping your cells at top voltage all the time, how many years does it take within you notice decrease in capacity etc. and it starts to be worn?
To charge LiFePO4 cells. This charger does not support 3.7V or 4.35V chemistries, which most people will never need anyway. Multi-chemistry support is indeed mostly just for feature fluffing.
As others said, 3.7V limit is also useful for storing li-ion cells in their “relaxed” state. Even this is questionable, however, as they will still self-drain and require routine “halving off”. In actual “storage”, this maintenance seems unlikely to happen.
Adjustable voltage limits are useful, regardless. I’m pretty sure that TK charges her cells to 4.15V to avoid 100% top-off. I would do something similar if I could. Yes, this is unnecessary as our cells are quite durable even when kept at 100%, but some of us are geeks in different ways; I’m an optimizer by nature.
Imagine how annoyed I am that I cannot “fix” my smartphones to keep them from killing their own batteries :smiling_imp: . The desire for longer runtime right now means that they sacrifice long-term battery life. If there was just a setting to reduce the max charge to 96% or so like there is on my laptop…