Mobile phone replacement battery supplier

[AE-NMidlands]

As above... has anybody got recommendations of good firms or ones to avoid? I'm aware of the risk of buying a dud if I just take the paid-for ad on Google, or get the cheapest from China...
I was recommended IFixit but but it just tells you how to do it (simple on a 6-yr old Alcatel phone) then directs you to a non-existent external site for the sale!
Why are things never straightforward?
Thanks
A

[Thebeeman]

Personally I only use "Original" batteries. If they fail or screw the phone at least you have some comeback.

[Stinsy]

We are an Apple family. Took my son’s 12 pro into the store, for £60 and under 2hrs they fitted a new battery. Genuine Apple repair too. I was quite impressed with that!

[Tay]

As above... has anybody got recommendations of good firms or ones to avoid? I'm aware of the risk of buying a dud if I just take the paid-for ad on Google, or get the cheapest from China...
I was recommended IFixit but but it just tells you how to do it (simple on a 6-yr old Alcatel phone) then directs you to a non-existent external site for the sale!
Why are things never straightforward?
Thanks
A

You pays your money and takes your chances to be honest.

I've paid a lot and the screen cracked within a few days of battery being changed, another one I paid £35 at Timsons and got a new battery that Apple refused to change. I still have the iPhone 6S 3 years later and still working perfectly as a spare, currently updating to its latest supported IOS as I write this.

Take it to Timsons if you have one of those around you, they say soon enough if they can help or not.