Seem to need a new one. The last one (GS) was bought from a local garage for convenience and took a long time bench charging after purchase to reach full charge, suggesting to me it had been self discharging on the shelf for a long time.
This might explain why its only lasted a couple of years (and/or or my cheapo Chinese Charger, or topping up with filtered rainwater, killed it)
I’m thinking maybe a dedicated battery outlet might have higher turnover giving longer life. I know of a couple of places in Tainan.
Any experience or suggestions?