Takes 1301 watts, about the same amount as some hair dryers. That would depend how many amps you want to charge it at. Wattage is the overall measurement of power that flows through your charger, so a higher cell phone charger wattage means that your device will charge faster. ... 36V 13.8Ah Rechargeable Lithium-Ion and the battery charger states it has input of 240V ~ 4A and output of 41.8V =-=-= 6A. The battery charger for an electric car isn't powering the motor directly. Reply • June 16, 2014 at 10:29 am BatteryStuff Tech You will not damage anything by running the system this way. The Battery Tender Plus 12V 1.25A Battery Charger is smart charging made easy. Think of it this way – charging at 16 amps vs 40 amps is like trying to fill your pool from a … Given that an average car battery has 48 amps, a 4-amp charger will often take 12 hours while a 2 amp one will have you waiting for the next 24 hours. If you're shopping for a new charger and the wattage isn't listed, you can also calculate it with the formula: watts = volts x amps. By using a 240-volt circuit (such as the outlet for an electric dryer ), the car might be able to receive 240 volts at 30 amps, or 6.6 kilowatt-hours per hour. To determine how long it would take to fully charge a battery with a capacity of 200 amp hours, use this equation: Number of watts ÷ 12 (volts) = amp hours So how do all these things work together to power your device? Use the total wattage, plus 20%, as your minimum power requirement. They are ideal if you’re not in a hurry or if you’re recharging a car you rarely use. Ohm's law says: Amps=Power divided by Voltage So, if you used 12 watts, you would be charging the battery at a 1 amp rate (very slowly.) How Volts, Amps and Watts Charge Batteries. It puts energy into the battery for use later. BatteryStuff Tech Ideal charging amperage for both the charger and the battery is about 10% of the battery’s Amp/Hr rating. An average car battery has a capacity of around 48 amp hours which means that, fully charged, it delivers 1 amp for 48 hours, 2 amps for 24 hours, 8 amps for 6 hours and so on. Note: The wattage's given below are estimates. Allowing for thermal losses it would draw about .200 kilowatts. How Many Watts Do You Need? If the charger was the typical McParts store model it had an out put of approx 10 amps at 13 volts which equals 130 watts, or .130 kilowatts. A standard plug-in battery charger runs at 100 watts. The 12V “car port” outlet on the portable power station can only give you 10 Amps – not sure why it’s limited like that, but this could be an issue (same limitation on their bigger powerpack). 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. For a car battery, if the car battery is over 40AH, then you can use a solar panel up to 10 watts without a controller without any issues. These are basic car chargers and will often take long to recharge your car batteries. To select an inverter from DonRowe.com that has enough power for your application, add the watts for items you may want to run at the same time. This car battery charger is fully automatic and easy to use. This Ford Focus charged 20 hours so that it could achieve it's range of 70 miles on a full battery. With a larger battery such as yours we would recommend a marine 12v 10 amp charger such as the NOCO Genius 12v 10 Amp Marine On-Board Battery Charger, or a USA made Dual Pro 12v 10 Amp Sportsman Series On-Board Charger.Our preference would be the USA made charger … Since the battery pack in Jon's car normally needs 12 to 15 kilowatt-hours for a full recharge, it can take 10 to 12 hours to fully charge the vehicle using this technique. This car battery charger features a quick connect harness and includes ring terminals and alligator clips that are easy to hook up to your battery and get your car going again. The 16 amp circuit you apparently have for the charger you use will fill the battery, so in that sense it is “appropriate,” but it takes much longer to do so than with a 40-amp circuit.