Help battery.. app limit charge to 90%?

[InGearX]

so apparently to prevent battery degradation for lithium-ion battery (sometimes Li-ion battery or LIB) that most cellphones use ..

it is to charge it to 90%
and discharge it a bit .. but say to 80% and repeat the cycle

The top 90-100% of a battery's capacity is very slightly damaging to the battery, which likes to stay in the 3.7-4.0V range (about 30% to 90%). 4.0v to 4.1v is about 90 to 100%, and 4.1v to 4.2v is "you can cram in about 5% more at your own risk" territory. The charge lingers around the 100% mark to cram more power in without exceeding 4.2v. This is why devices are shipped half-charged, not full-charged: the batteries are manufactured at a stable mid-range voltage and charge level. Then, they're tested and returned to that half-charged state for storage (!) and shipping. They like to stay in the middle, not the extreme ends (and definitely not fully discharged).
Charge algorithms are designed solely with capacity in mind, because not much care is put into "how long" something will last. They'd much rather abuse the battery and have the battery (or the device) replaced, than to put a larger battery in to make up for lost capacity by charging only to 80%.

For some of us, we understand that, and we'd like to limit our battery charge so the life of the battery (the capacity it will hold over time) will stand up to the test of time. If treated right, these batteries could last over 10 years. Charging to 100% each day and staying there all night (most of the time, it charges within an hour, leaving it sitting about a quarter of its life at a full charge) is pretty destructive, compared to using an app that caps it at 80% each night, saving the full cycles for monthly battery-meter refreshes.

Charge/discharge efficiency 80–90%[4]

https://en.m.wikipedia.org/wiki/Lithium-ion_battery

or watch first 2 minutes from this video

well some laptops like screenshot from VAIO have this feature as an option
see this http://images.google.com/images?q=sony+vaio+battery+charge options
(as i have "You may not post attachments")

GOOD info http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries/

more on the topic http://gizmodo.com/you-should-try-to-keep-it-north-of-50-percent-as-much-619313207

more http://android.stackexchange.com/questions/57271/charge-level-control

question:

why don't smartphones have this option - to limit to 80%?

sounds like there should be even a firmware option .. from manufacturers ..

any manufacturer has this?

i assume there is no way to control the hardware .. so no application to do this ..
in one way it is good for manufacturer .. you will buy a new device .. in another way its bad .. they are selling you hardware that is not taken full advantage of .. so manufacturer that will will prevail ..

thank you ..

 

[nik80]

there is 2 reasons
1st - by squeezing the last mAh from the battery they can advertise longer standby/talk time ( who care if that damage the battery )
2nd - actaully somebody do care about damaging the battery - the manufcturer.... programmed dead of electronic devices is well known practice, many devices are designed to fail after certain time, which make the customers to buy new device again and again

some devices have the ability to control their charges, and there is already one app which is preventing overcharge, but it is still at very early stage of development, and working on very limited number of devices
unfortunately my charger is completely out of control, the only I can do is to unplug it early, because it is designed to always overcharge to 4.4 volts. which guarantee that the battery will be useless in less than 2 years. where the need to replace a built in battery will make many customers just to buy a new phone
its all about money