On Saturday, April 8, 2017 at 9:41:17 AM UTC-10, wrote:
> looking to buy my first Smart cell phone
> [currently i just own a simple cell phone, no www]
>
> i don't plan on using it that much,
> and i see a few have replaceable batteries,
> and was wondering if that would come in handy,
> 5 years from now if/when the battery dies
>
> how long do these smart phones batteries last?
> i assume they die eventually
>
> thanks
> marc

If you use it every day, the battery should last 2 years. By that time you might notice that it's not lasting as long. If you don't use it very much and don't charge it every day, it should last longer. If you're like me and tend to discharge the battery fully almost every day, it should last about 18 months or 500 full charge cycles. After that they tend to not take a full charge. When this happens, the battery will charge and discharge faster i..e., the capacity will shrink.

If you aren't going to use it much everyday, I recommend that you keep the battery topped up. Your battery will last considerably longer. All this refers to modern lithium ion batteries with modern charging system. The older batteries do not like to be treated this way. Welcome to the new world.