the reliability of samsung cell phone batteries are getting better and better by the year as battery technology is improving considerably given you longer talk time and better storage time on your cell phone. Make sure that you do not put your battery into extreme environmental situations like extreme heat or extreme cold is that will shorten the lifespan of your battery in your cell phone will not work at a top level with a battery that is down to so many different situations. Always make sure your batteries charged after a day of use, to avoid any problems in the future