I know Dyson DC 35 uses a battery that converts ac charging source to low v DC power. Am asking about charging ac source of 220 v.

SOURCE: My PC won't run with ac /dc power!

Hello. There is a hardware failure with the laptop not the AC charger. AC chargers have some range of protections of their own. If the power requirements of the laptop are bigger then what the charger can handle, the charger will turn off. Also other parameters can bring the charger offline. In your case, you have a problem with a small chip, the battery charge controller unit, witch regulates the amount of current required to propperly charge the battery. When this thing fails, the charging requirements for the battery are reported rong and the AC charger is forced to give more power then necesary. This results in disconnection of the AC charger ( an internal fail safe of the AC charger) and the laptop to swich back to battery power. When the laptop is turned off, it can charge the battery because the power requirements are low, having all processor, main board, hard disk etc turned off. Therefore the AC charger can handle the load. However you will need to have it checked by a service center as it is a hardware fault. Both AC charger and laptop needs that check. The charge controll circuit needs to be replaced probably. It will be a somewhat expensive repair. Don't buy any other battery untill you have the laptop checked. For more aditional info please post back. PS. Sorry for my bad english, I am from Romania, it is pretty hard for me to explain tehnical stuff in english.

SOURCE: Toshiba Satellite A105

The most common problem on these units is the ac connector solder joints break away from the motherboard. If you're sure the ac adapter is working, and the correct one, and it's not charging the battery (assuming the battery is good), it's most likely the problem. They don't have to appear loose to be loose.
Otherwise, it's motherboard time, or a loose screw, etc has caused a dead short on the board.
Good luck, if you have additional info, let me know.

SOURCE: Toshiba M115 S3094 Battery Probelm

Your battery not able to hold a charge is a bad battery.
Love your precise description & diagnoses. Wish others would describe their troubles as well as you!

Have a great day!

SOURCE: power policy manager unable to set policy

You're going to need to go to the link bellow and download the latest power management driver. If it's just an incompatibility issue, the download will fix it. However, many time it's actually a failed component in the power management system, so, if the download doesn't fix it, then you can assume it's a failed component and you might want to have it professionally traced down to the exact component for repair.

http://www.ibm.com/products/finder/us/finders?pg=ddfinder&Ntt=ThinkPad+T40+&lc=en&sid=298702491219786380769&tmpl=%2Fproducts%2Ffinder%2Fus%2Fen%2Ffinders&Ntk=text_gensearch&cm_re=other-_-suprcn-_-download&N=1000367&collectionN=0&cc=us&finderN=1000188&

SOURCE: Hellow Dear, My acer aspire 4935

First, you need to make sure your power adapter is providing enough power to both run the laptop & charge the battery. A very good way to do this is to compare your laptop voltage & ampere requirements (written on a sticker on the bottom of the laptop) with the voltage & ampere ratings of the power adapter. Voltages should be the same, or the power adapter's voltage about up to 0.5 volts more than the laptop's voltage rating. Amperage of the power adapter should be at least equal to or greater than the laptop's rating. It should never be less than the laptop's rating, or else the power adapter will be providing insufficient amperes to charge the battery. Of course, the power adapter's nominal amperage might be ok, but it degraded on usage. You can verify this by testing using a good or new power adapter.
If the battery did not charge using the new power adapter, take the battery off the laptop, & using a dry tooth brush, scrub in between the fins of the battery connector on the motherboard & on the battery it self, then put the battery back into the laptop & try again.
If this still did not resolve the problem, then the battery itself could be bad. Try it on another laptop, or try a good or new battery in your laptop.
If this did not work, there might be a possibility that the charging circuitry on the laptop's motherboard is defective & needs servicing. In order to do this, the laptop needs to be disassembled & the motherboard checked for defective/burned out components in the area near the DC jack. Any defective/burned out components found should be replaced, or you might need to replace the laptop's motherboard altogether.