[ELI5] How do “OEM replacement” batteries exist for a device that is several years discontinued? And do they genuinely work better than the battery they are replacing?

Question

I bought a used $20 Samsung Galaxy J7 (2015) since the screen looked to be in perfect condition. I do not know if the seller replaced the battery, but even so, how would a “brand new” battery from 2015 be any better than the current battery inside?

In: Technology

Answer 1

Samsung makes a choice for every part in the J7, “should we make this” or “should we buy this”. Some things are easy buys, nobody makes their own screws. Other things are easy makes, they are the secret sauce that makes the product better than the competition.

Alas, most things are in the middle. Battery is a great example. You can make your own battery, but can you make is better/cheaper than a battery company that makes nothing but batteries? Probably not. So, you buy the battery. That battery maker (the original equipment manufacturer) is in the battery business, they may be making that battery, or selling new batteries from the end of the production run, years later.