The information you don't know about the iPhone battery
What we want to know when we find a battery replacement is whether this battery still functions well, how good it is and how many charge life cycles it still has. So actually we test the output current, internal resistance, internal voltage, protective discharge voltage and lifecycle times, and the most importantly: the battery’s capacity. Know more about it here:https://www.etradesupply.com/blog/some-cellphone-battery-information-90-people-dont-know/