The battery may need replacing as it has either run its life or is faulty. Check the fuse in the plug on the lead that plugs into the laptop, if this does not work there is a fault in the laptop.
The most likely problem with your laptop is the charger has gone bad, and or the port in which the charger inputs has been fried. I suggest you contact the manufacturer for a replacment
Since the laptop will not run without being plugged in to the battery, then you probably have a burned out battery. You can buy a new one. Running it like this for too long, however, can lead to other problems with charging. Good luck.
What is wrong with your laptop if the battery is flickering and it won't run without the battery it is time to replace the battery for your laptop which in most cases shouldn't be too expensive
As batteries age, they eventually fail to be able to hold a charge. What you are seeing is that your battery is charging, then full, then a short time later it is not full, so the charger kicks in again. The battery can't hold energy, so the powerpack must.
Your laptop won't run without the battery, but it should run for a while even if it's not being charged. If you have the battery in, but the battery icon is blinking, you need to charge it. If it won't charge up anymore, you need a replacement.