On 14:54 28 Apr 2021, Chris Green said:

In uk.d-i-y Pamela wrote:
On 12:55 28 Apr 2021, Theo said:

In uk.d-i-y Chris in Makati wrote:
Phone manufacturers source their batteries from various
third-party suppliers. Each of those suppliers probably sell
their batteries via different channels to any number of other
customers.

So is a battery still "genuine" if it came from the same factory,
but didn't have a particular label on it?

I think the 'made in the same factory as Kelloggs' argument is
overdone. Most top-tier brands (Apple, Samsung, etc) have
agreements with major contract manufacturers (Foxconn, etc).
Foxconn have enough of a reputation to protect that they won't
build knockoff iPhones on the late shift and let them into the
market.

However a manufacturer can run two lines with one producing
batteries of lower spec (and lower cost) than the other.

It's *possible* but if you think about it that's quite difficult to
do. In reality having a single production line producing just one
type of battery would probably make that battery cheaper than both
types being made on two separate production lines.

It doesn't really matter whether a different physical production line
is used for each product or they share the same line but different
materials are used. In the end, a single factory can produce one
battery at one price and another battery at another price.

A factory's purpose is not to product the highest quality fault-free
items possible. It's purpose is to make a profit at any level of
quality and that might mean providing the market with offerings at two
different price points.