An article today said using your phone battery below 20% and charging it routinely above 80% reduces battery life…what causes this and is it the same process at both ends of the range?

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An article today said using your phone battery below 20% and charging it routinely above 80% reduces battery life…what causes this and is it the same process at both ends of the range?

In: Physics

3 Answers

Anonymous 0 Comments

Isn’t the 80/20 thing BS? Or at least the science behind battery technology is too finicky to say?

Anonymous 0 Comments

ELI5: Discharging a battery too deeply causes its structure too break down, increasing the potential for a short circuit. Overcharging has a similar effect, but can also result in the battery catching on fire. Discharging from 80-20 slows the breakdown.

Full Answer:
When discharged below its safe low voltage (exact number different between manufacturers) some of the copper in the anode copper current collector (a part of the battery) can dissolve into the electrolyte. The copper ions then in turn can stick on to the anode during charging by chemical reduction and cause dendrites. The dendrites might cause a short circuit inside the battery. So basically discharging too much is as bad as charging too much. But the dendrites caused by overcharging is formed out of lithium.

Normally the battery pack should have some sort of supervisory circuit that disconnects the cells from the charger or load when the cells are above or below the recommended voltages.

Anonymous 0 Comments

Like your five? So batteries, all batteries work because the world is charged, either positive or negative. Batteries are arrange to store positive charges and “discharge” them to a negative, like a remote without power. Eventually a battery runs out of positive charge and both the battery and remote are negative. Adding positive back to the battery creates heat, mainly because nothing is perfect and some of the positive charge leaks away as heat. This heat slowly reduces a batteries ability to both discharge it’s positivity and receive that positivity until you get mad one day and replace your battery for a new one that isn’t worn out from the heat and the work it has done. So, directly answering your question around range. A battery doesn’t get as warm in the middle of it’s charge as it does when it’s out of positive charge or nearly full. #chemistry (another long explanation)