Question about cell phone batteries (T-Mobile, iPhone, charging, battery)

[TravelingBoat]

How long do cell phone batteries normally last until they need to be replaced?

I've had my T-Mobile emergency cell phone for over 2 years. Seems like the battery drains faster than normal.

[Mr5150]

Two years is about right for loss of capacity. Just how it is.

[Mr. Lee]

It depends on the size of the battery, what items you keep on all the time, such as data, wifi etc, thus how often it needs to be charged, I get around 2 years with charging every day to 3 days, depending on how heavily I use my phone those days. Just buy a new battery on ebay, search for OEM battery and your make and model number, they are inexpensive to replace. In the old days I used to get a week out of my non smart phones.

Six questions about your phone's battery answered
The lifetime of batteries measure in cycles differs between different devices, but typically have between 300 and 500 full cycles before they reach 70 per cent of their original capacity - equivalent to a couple of years of use, although this graph from Battery University shows that capacity begins to drop fairly quickly:

[Lara S.]

All smartphones have limited numbers of recharge cycles. There are applications that show how many recharge cycles your battery has undergone. This is one of such programmes for iPhone https://imazing.com/ Your 2-year old device probably went through over 600 recharge cycles which is really a lot. My iPhone 7 is much younger, but - oops - I've already got the batteries changed. This repair shop https://misterfix.us/shop/iphone-repair/iphone-7/ took about $70 for services (I was staying in Hampton when all these drain problems started). But they did everything quickly (I waited 15 minutes at the utmost). Maybe I could have replaced it myself… But I didn’t dare to open iPhone.

[Peregrine]

As was said the 18 month - 2 year mark is really when they start to fade.

[Mr_Geek]

2 years is typical for needing replacement.