My 5 year estimate may actually be outdated already fortunately. First article popup about it shows 8 to 12 years now depending on the company and battery type. This is actually fantastic to see that as I was quite worried the tech would stagnate eventually.

https://www.pcmag.com/news/how-long-do-ev-batteries-last-study-says-longer-than-you-think

I have a 2015 leaf and while the estimated battery range has gone from 90’s to 60’s on mileage, it’s still kicking and gets me around the city just fine.