Asus eeePC Charging, Battery and Power-Saving Tips
When you first take your EeePC out of the box, you have two options. First plug in the unit to mains/wall socket.
The orange charging light will come on and you can let it charge fully for about two hours.
You can power on the unit and use it while it is charging. It will take MUCH longer to fully charge. Either way, do not unplug the unit until it is fully charged and the orange charging indicator has turned off.
The EeePC comes with a lithium-ion battery, so there's no need to fully drain the battery while charging. From the "Battery Low" warning, it will take about 2 to 2 1/2 hours to fully charge while plugged in and powered down. You can use it while charging and expect the battery to charge about 10% for every hour it is plugged in and powered on.
If the battery is fully charged you can remove the battery and use the charger as power source as long as there is a power outlet in the near.
Note: This applies to a 4GB unit with the 4 cell battery (5200mAh).
You can expect at least 2 1/2 hours battery life, even with the screen brightness on high and wifi turned on. Being idle you may get 4 hours of battery life.
The Surf models with 4400mAh batteries will be able to get about 2-3,5 hours at most doing the same tasks.
Memory Effect, Weardown, 'Dead' battery
Allthough Li-Ion batteries come with a 'NO-memory-effect' (the effect of losing battery life when not being fully decharged before recharge in the old Cd batteries); they do run out like any other battery out there. The phenomenon 'weardown' applies whenever a battery has been used to the extend that 80% of it's starting capacity is still functional.
The time, before the 'weardown' phenomenon takes place is estimated to be arround 1 year of continuous use (charging/decharging), or 2-2,5 years in normal use (depending on how the battery is been used). Ofcourse Weardown isn't a direct phenomenon, it happens gradually over the course of the battery's life span. Once the 80% mark has been reached, the battery will further lower in life and performance, and it will be apparent to the user that it it's performing less then in the beginning.
When not having used the battery for a long long time, or when the battery is close to being empty it will need a recharge. It is important to recharge the battery before it's completely empty (Dead battery)! If your battery has reached there, it will be very hard to impossible to recharge/recover the battery again, since Li-Ion batteries require a charge voltage to be remnant in order to be charged. Your best bet is to plug in the AC, and try to recharge your battery. Probably the Eeepc won't recognise the battery. If it does recognise, the recharging process could be a long one;[may need days of charging] to get the battery fully functional again; (if it ever could get back that is)
Your battery has an internal cpu(stored in the battery hardware), that will:
* keep track of recharge cycles: which will make sure every cell has been charged equally (so that not one will be continuously balasted and suffer of 'weardown' but a 'rotation cycle' of internal cells will be done). * do voltage measuring: a probe for internal charge load. * contains battery information: like the battery name, ?serial n° and other info? <- not verified
Using External (home-brew or DVD player) Batteries
People have [building] battery packs, but batteries are fickle and there is a real risk of frying your eeepc. Luckily the eeepc shares a battery consumption needs of many portable DVD players, and so [reports of using DVD player batteries] may be more useful, reliable and quicker than following home brew solutions.
* Use the Fn+F3 to reduce screen brightness as low as possible (Use Fn+F4 if you need to increase it). * Use Fn+F2 to turn of the wireless network when you are not using it. * Use Fn+F7 to mute the speakers when you are not using sound. * If you're not using wired LAN, you could disable it in the BIOS. Remember to enable it before plugging in an ethernet cable, or you'll wonder why you can't access the 'net! * If you're not using the webcam, disable it in the BIOS. * Adjust screensaver settings. * close_lid_shutdown * To increase battery life from weardown-effect (see above), when using the EeePc, use the AC(/adaptor) as much as possible! * Refrain from charging the battery when you don't use the Eeepc, unless if you know you'll need the battery soon. Meaning: DON'T keep the Eeepc continuously connected to the AC. * In the case of unplugging and storing the battery away for looong times, first fully charge the battery, and recharge about once or twice a year. If not recharged in a long time, battery might become dead.
http://wiki.eeeuser.com/guidebooks:charging (permission was granted)