Thx for the useful info on battery lack-of-fail-warning, a surprise for me.
I checked the owner's manual and only says it is a "maintenance-free" battery (pg.7-34).
Does recommend to "inspect battery condition" every 7,500 mi/6-mo. Probably means just exterior ?
Also, calls out different recharging rates, depending on how it got discharged, AND, to remove battery from car when recharging.
Finally, does describe what to Reset after battery has been disconnected: auto-windows, trip computer, climate, and audio.
I guess i'll get a new battery, after almost 5-years (58-mo.) from date of manuf .
'15 Soul EV+, '10 Prius