Trojan T-105

I used four Sams 12 volt rv / marine batteries in series to Power a 48 volt Ray outboard motor. I used an Lester industrial charger which finished at 61 volts on every charge. I bought them in 2008 and one failed in 2009 under warr then I replaced one in 2016 and 2017. I sold it last summer with 2008, 2009, 2016, 2017 batteries and they served the new owner all summer. These had also been run down very low a few times when visitors left an inverter on. They were never low on electrolyte.
More batteries die of under charging vs over charging