[FAQ] The definitive thread to battery related matters on the Asus range of tablets

[cngalore]

Hi, I'm curious to know if using the combo on AC power when the tab and dock are at 100% is doing any harm especially for prolonged usage.

Id be interested to hear anyone's thoughts on this.

Thanks.

[Ads]

[eejit]

Welcome cngalore-it's not a recommended practice, leaving them plugged in alla time. (Though my dock is probably on %85 of the day. ) I believe the stats show ideal battery life is attained when the tablet is drained about half way, then recharged. Why? Well it's got something to do with bananas, not plantains, bananas... actually I don't know the reason why that's the number, somehing to do with the cycling(?)

[Swipe]

I believe the recharging advice as well as not always running through the AC adapter are related to heat. I find that charging my tablet via the adapter while docked results in less heat generated. There are links in this thread to articles on optimizing battery life.

[cngalore]

Eejit and Swype,

Thanks for the thoughts! Yeah, I'm familiar with the cycling/maintenance aspect of battery management but I suppose I was asking if the charging mechanism is smart enough to shut off the charge when both Keyboard and Pad are at 100% and switch to AC power supply only - to prevent 'overcharging' ?

Like they say just take basic precautions and enjoy your toy rather than worry about it!!! Im still trying to adjust to this concept after so many years!!!!

[eejit]

^^^^^^^
Good question actually. Unfortunately, good questions usually stump me.
I don't think I've read anything mentioning overcharging, is it possible to even over charge this battery type?
Um, not sure. I have seen both my tablet and dock 'sit' at %97-%98, still plugged ino the charger...I don't think
they charge before a certain level...but dock my tablet when it hits low 90's, charges all the way to full.

Yeah, probably not the answer you were after.
I've had my tablet coming up on a year, dock is usually charging and has no issues .
Tablet rarely get's below half charge & hardly ever gets turned completely 'off, and has no issues.
Don't worry too much over it, in Latin---> seize the fish.

[janner43]

@cngalore

The reasons not to leave the mains charger plugged in permanently, seem to me to be these...
1. Asus don't recommend it
2. The alternating cycle wave form of a/c passing through the circuitry of the very dedicated and fairly expensive Asus power adapter will cause premature failure of the expected life cycle of the charger which was not designed to be left connected all the time ( entropy increases over time)
3. It poses an increased fire risk
4. Opinions vary as to whether permanent connection to a charging circuit can damage a battery - I take the view that it does.

But, then again, I do,leave one particular phone charger plugged in most of the time because it is awkward to get to the switch, but that is an inexpensive and easily replaceable 5v/1a charger.

I don't think anyone knows for certain if the TF range are wired in such a way that means a/c is used from the charger if the battery is charged but the device is still connected to a/c.

One of our Forum Admins works at a senior level in the electrical generation business & in his very educated opinion, the TF would still work from a/c even if the battery was completely duff, but even then that is only an educated opinion, rather than a clear fact. So at the end of the day, I guess the only thing left to say is this...

Your kit, your choice

[awkwardchris]

I'm having trouble with my TF300t. It seems that when the tablet is docked and the dock is plugged into AC outlet that both batteries are supposed to charge, but this is not happening. Only the dock is being recharged, while the tablet battery continues to drain. The dock is now at 100% but the tablet has been discharging and is now down to 53%. Even if I unplug the AC power from the dock the tablet does not start to charge. It seems that the only way for me to charge the tablet now is by plugging it in directly, so I have to charge the dock and tablet separately. The LED which shows that the device is charging will come on on the dock, but not on the tablet while it is docked. If I plug the tablet in without the dock then everything seems to work (charging and LED). Another thing slightly disconcerting is that if I apply just the slightest pressure to the back of the tablet while it is docked the LED does come on, but it does not show that the device is charging (not in the widget, statusbar, or battery part of the settings menu). If I put a light weight book or my cell phone on top of the tablet and closed dock, and leave it for a few hours and it seems that both actually charged some when I do. What gives? Is this a problem with the tablet or the dock? I think and hope that it is just a poor connector on the dock.

Sent from my ASUS Transformer Pad TF300T using Tapatalk HD

[TheFoxMan]

janner43 - thanks for the detailed guide. Sorry if this was covered and missed by me, but will the Dock battery charge when connected to the PC via USB, with or without the tablet docked and off or sleeping? I'm thinking no, but wanted to confirm.

[wombat7]

New to TF300. When looking at battery status I can see when 100 persent charged etc. but wonder what the entry llm47s on battery means.The battery is charged to 97% presently.

[misko288]

Hi
my tablet was working normally... usualy i had charged it about 3 hour...
yesterday i wanted to charge my tablet but when i plug in the charger tablet just wake up but charge indicator is not showing !!!!!! i tried alot of adapter and same
its charging but veeeeeeeeeery slow like 90ˇ% at 16 hours . but indicator isnt showing that the tablet is charging but its charging but very slow someone please help me please