I have a 12 volt Rechargeable Sealed Lead Acid Battery type FM1275C (probably Chinese) rated for 12v 7.5Ah and 20 HR charging (written as 12V7.5Ah/20HR on the battery). In my arsenal i've got a voltage regulated non PWM power supply able to supply 17 volts @ open circuit and 11.5 volts @ its peak 3Amp current (so its a 12 volt 3 Amp capacitor smoothed voltage regulated power supply). I took the battery from a portable generator. At the beginning it was able to start the generator's engine but now its not. It is currently charged at 4.7 volts and can supply a maximum of 300mA at this state.
Can you guys tell me how can i charge this battery through the power supply?
Thanks in advance and have a GREAT day