my lappi battery is completely dead..it says consider replacing ur battery

no back up...cn i use lappi as pc means always connected to power supply or is it necessary to buy a battery?? does it alter the performance of lappi by alwayz connecting in AC mains....
Yeah you can use it without a battery and only on the mains but keep in mind that if power failures are common in ur area it can damage ur lappie especially movable parts such as hdd
No loss in performance etc whatsoever but I would recommend getting a battery just in case (original only) and if u have the budget
It's safe to use it on mains 24/7 I do it all the time while gaming or torrenting at night
On the other hand the laptop temperatures can reduce upto 10c (in my case it does)
Hope I helped