[amr ashraf mostafa]

Can i charge my iphone 6s plus with a faster charger than the original one without affecting the battery health as the original one charges the phone in 3 hours?

[Just_Me_D]

Yes. A good deal of people use an iPad charger to charge their iPhones.

[amr ashraf mostafa]

Yes. A good deal of people use an iPad charger to charge their iPhones.

And does this affect badly the battery health of the iphone?

[Just_Me_D]

Not in my experience.

[amr ashraf mostafa]

Yes. A good deal of people use an iPad charger to charge their iPhones.

And which ipad charger compatable with the iphone 6s plus?

[Just_Me_D]

I simply use the charger that came with my iPad.

https://www.apple.com/shop/product/M...apter?fnode=91

[IAmSixNine]

You can use a 10 amp charger if they made one, the phone its self will limit the maximum amount of current input.
However, the more current input you have and use the hotter the battery will potentially get, so if you opt to use this method try to let the phone rest. Using the phone while charging will produce even more heat. Heat = bad for batteries.