I’ve been thinking about it. Battery prices have not gone down in the last few year and have actually risen slightly.
Not sure that that is correct for batteries per se, just for Tesla Powerwalls! A friend has recently ( a year or two ago) set up his autonomous system and it cost him less than $85k ! (It’s.a big system!) His batteries are some new fangled things that are starting to be built in bulk - he’s confident that prices for them are plummeting.
Don’t forget in the tesla increase - you get “more” now!