For all you electrical geniuses out there…If I am running two 55 watt 12 volt lamps on a Optima car battery (900 cold cranking amps. 800 amp reserve)
How long will my lights last?
Is there a better, lighter battery out there?
Not enough info
Is there an Amp-hour or Ah rating shown on the battery?
looks like it’s 44 amp hours nm
Ok
110 watts / 12 volts = 9.1 amps.
44 amp-hours / 9.1 amps = 4.8 hours
In reality, you’ll get less than that.
car battery
Car batteries are not designed to be repeatedly charged and fully discharged. A car battery won’t survive may full discharge cycles.
You want a deep discharge battery, like those used for trolling motors.