The circuit depicted should only be used to "equalize" flooded-cell lead-acid batteries; never use it on sealed lead-acid (SLA) or AGM batteries. This is a "constant-current" type of charger; it is not a "voltage limited" charger, which is what should be used for routine recharging and float-charging of lead-acid batteries.
An "equalization" is a controlled-overcharge, during which the electrolyte bubbles and is used up (that's why not to use this on SLAs), The specific gravity of the electrolyte is driven to a higher level than normal, and by overcharging some cells in the battery, the other cells are brought up to higher level of charge to hopefully equalize the state-of-charge in all six cells. It should not be done for more than four hours once per month; it is hard on the battery.
If you insist on using this for "recharging", rather than for equalization, then you will have to monitor the battery closely during charging. Watch for it to begin gassing, heating, or periodically measure the terminal voltage (under charge). Quit when the battery voltage reaches ~14.6V. Do not leave this thing connected to a battery overnight, or it will be toast.