Hight voltage kill adapters on both of my laptops. I am buy one adapter what is not original but it is universal. My original adapters have 18.5V and 2.7A and this universal I can put on 18V and I think 4.5A. Can this adapter kill my laptops.
The Universal adapter will work with 18V and 4.5A, as long as the amperes is not less than 2.7, it is ok.
Usually the components in the laptop regulate the power and protect it from over voltage, and usually its the second line of failsafe... the first one being the adapter itself, as these are cheaper (sometimes).
I am little bit worry about 2.7<4.5 Amperes and hope with this 1.8 A differences will work well.
if my phone charger is 1A, what will happen if i use 2A charger? will it charge faster? will it damage the phone/battery? or nothing will happen because it will output whatever current draw by my phone/battery?
I don't think so the high voltage can "burn" your laptop. The difference of voltage is too short and you have a good shore of current. If you want to charge faster, use a highter voltage with the battery out from laptop.
Is like car battery charge. Can be slow (better) or fast (don't recomended, but faster).