It’s 61Wh when you need it.
And its lifespan is fine if you’re not abusing the hell out of it. Sorry, but holding li-ions at 100% 24/7, day after day, is very hard on them. And that’s how all li-ions are.
I limit charge when plugged in for an extended time on all my devices.
For android, there is Advanced Charging Controller App (AccA) which offers options to dial back the charging rate as well, when you don’t need fast-charging, or optionally when battery temperature is over a configurable threshold.
It has schedule options too. For example, if you plug in your phone before going to sleep, as most do, you can create profiles to have it at 100% right when you wake, without the normal fast-charging & holding at 100% all night. Avoiding all that unnecessary battery stress. Instead it can slow-charge to a limit you set, holding that during the night. Then, shortly before morning, contiune charging right up to 100%, just in time for you to wake & take it off the charger. You have both 100% and you’ve prolonged the useful life of your battery. No downside.