I also am gonna part w some observations inre to my 2021 54" 48v ZT.
I know I have had it easy compared to many of you. Until today.
Glad I kept my 2005 50" Dixie Chopper. My Ryobi 54" ZT basically just died; on full charge, mower moves and blades briefly come on, but that is followed by a loud beep and the blades cut off. I hope it's just the batteries.
I really like the mower itself, but batteries have never been up to my task (on 4 acres, ~ 3-3.25 mowable). In the best of times I got it done over 2 days.
In this my 3rd season -- @ 200 hrs -- it was a struggle to mow for more than 20-30 minutes. Season 3 went from meh to $#!+ quickly. Seemed once I got past 150 hours things went downhill and fell off a cliff as I approached 200 hr. Today took the cake. Maybe that's the normal lifespan of these batteries?
I have noticed that despite being fully charged, when I unplug and then plug it back in, it will often charge for hours.
To Ryobi's credit, they stood behind the batteries after I complained; the new ones they sent are on a maintenance charger and I'll swap those in the spring. If u want more intel on the steps to get new batteries, lemme know. I am not swapping them now cos I don't trust the Ryobi charger to properly overwinter them (see #5).
The BLM is not much use. Rather, the mower sound gives it away when I'm about to lose the blades. Sometimes its at 30%, others (like yesterday) at 60%. Today it was at 100%.
I really, REALLY wanted this mower to work. But it's clearly not there yet. Not even close. I hope that maybe some day I can convert it to Lithium or swap in a longer-lasting deep-cycle SLA battery.
In closing, you all have provided excellent intel thru your discussions here. Thank you.
Best wishes,
E