TF700 Battery Charge Cold Boot Question

[loot55]

Hello all I'm trying to get the best outta my battery and I'm thinking on doing it like that.

I'm letting the battery on my TF700 get down to 4% then I want to do a cold reboot. If you're asking why here is why I'm thinking correct me if I'm wrong that if I do a cold reboot that the battery might give me a different reading like lower as if it will correct the battery? After the cold reboot I'm going to power off and charge it for 8 hrs then boot it up normal and use it.

What do you people think about this idea? Does it sound correct, will it not matter, would you do something differently? What % do you let your battery get down to before you charge it? When the green light comes on do you unplug it or let it charge more and if so how long?

P.S No dock, just the wall plug

Thanks

[Ads]

[MikeM]

Welcome to the forum.

It probably will not matter in the long run.

People here have tried all sorts of things and it doesn't seem to make any appreciable difference.

It seems like the biggest culprits are apps that connect on their own and screen brightness.

[loot55]

Thanks Mike

[rootbeerfloat]

To add, lithium ion batteries actually prefer not to go through deep discharge cycles. You can run the battery down pretty low every once in a while to make sure the battery monitoring gets recalibrated, but over the long run, you want to have a more moderate depth of discharge before recharging. See: How to Prolong Lithium-based Batteries - Battery University

[xRevilatioNx]

"Similar to a mechanical device that wears out faster with heavy use, so also does the depth of discharge (DoD) determine the cycle count. The shorter the discharge (low DoD), the longer the battery will last. If at all possible, avoid full discharges and charge the battery more often between

Let’s look at real-life situations and examine what stresses lithium-ion batteries encounter. Most packs last three to five years. Environmental conditions, and not cycling alone, are a key ingredient to longevity, and the worst situation is keeping a fully charged battery at elevated temperatures. This is the case when running a laptop off the power grid. Under these conditions, a battery will typically last for about two years, whether cycled or not. The pack does not die suddenly but will give lower runtimes with aging."

If you do a full discharge and then charge to 100%, you get only 300-500 charges.
If you do a 50% discharge & then charge to 100%, you get 1200-1500 charges

So basically, a full discharge can harm your battery in the long term. If you charge it and continue to charge it while you are on it, allowing the battery to run at high temperature, it can harm the battery. If you charge the battery at 50%,you will get the longest life...

Lastly, why does Asus tell you in the manual to charge up to 8 hours, if charging the battery at high temps -- caused by the power grid, can harm the battery life?

That would be my question......

[rootbeerfloat]

Lastly, why does Asus tell you in the manual to charge up to 8 hours, if charging the battery at high temps -- caused by the power grid, can harm the battery life?

That would be my question......

The "up to 8 hours" is funny to me. I think they just want you to go from shipped charge (10-20%) to 100% the first time around so the tablet calibrates correctly. 8hrs would be a full charging estimate if using a low wattage power supply, like "trickle charging" via computer USB port with tablet shut off (5V @ 500mA = 2.5W/hr) vs the outlet charger that delivers 15V @ 1.2mA = 18W/hr. Of course not all that power makes it to the battery as the charging circuitry uses some and also controls the rate of charge depending on the voltage level. You may notice that when charging with the outlet charger, you see different rates of charging before and after the 90% level.

Indeed it seems like 50% is a good target for recharges if you want to maximize the total number of Watt-hours your battery pack will get over its life.

Also, the high temp comment in the article is more a reference to a battery being in close proximity to hot components, like the CPU or hard drive, which can be 50 C or higher. More than likely, when your lithium ion battery starts to lose capacity, you're probably thinking of upgrading to the next generation device. :-)

[loot55]

Thanks for the info and links I'm going to charge it when it hits 50%. Also do you unplug it when you see the green light or do you turn it on and if it's at 100% you unplug it?

[MikeM]

Also do you unplug it when you see the green light or do you turn it on and if it's at 100% you unplug it?

Either way is fine.

If I'm not going to use it right away I usually leave it plugged in.