To calculate your total charge time for a battery, a good rule of thumb is to take the amp hour rating of the battery and divide by the charger rating (amps) and then add about 10% for the extra time to totally top off the battery. Some folks wanting quick recharge should look for a charger with more amps.
NOCO Genius G7200 Ultra Safe Battery Charger
NOCO Genius smart battery chargers is one of the most advanced and safest chargers in the market today. This G7200 7.2Amp is specifically for charging from 12V up to 24V lithium-ion batteries and lead-acid batteries up to 230Ah.
30 A 12 V charger can charge a maximum of 360 Watts. This information is intended to be at the battery being charged side, since at the AC mains side you can consider from 20 to 40% more energy being consumed .
If you're fairly average and drive 12,000 miles per year (1000 per month) and get 4 miles per kWh, you'll use an extra 250 kWh per month from the car's battery. Level 1 (120V) charging is about 75–80% efficient, so you'll use around 320 kWh from the wall.
A basic charger usually charges at around 2 amps - and so needs 24 hours to deliver the 48 amps needed to fully charge a flat, 48 amp hour battery. But there is a wide range of chargers with different charge rates on the market - from 2 to 10 amps. The higher the charge output, the faster a flat battery is recharged.