Battery replacement for iPhone 5s

I have experienced the dreaded "battery drain from IOS 11 software update" on my iPhone 5s since it came out in 2017. After adjusting every setting imaginable, deleting apps & disabling everything I could live without- via searching for these "answers to fix drain" on Youtube...it's steadily gotten worse & I have to charge at least twice a day with VERY minimal usage, if any in-between. I am willing to invest in a new battery because I do know these tend to wear out over time, but my question is: would a new battery fix this issue?? Or will the software still drain it?

If so, I need to put that hard earned money toward a new phone instead, hate this! It's in otherwise perfect condition & seems like I just got it paid off. arrrghhh 😐

Thanks for any advice! MB