How much AC is there in a car battery

[John1397]

I am thinking there is about 1/2 kilowatt hour of usable electricity in an 800 cca 12 volt car battery after conversion is this right?

 

[jedishrfu]

If you look at the specs for these devices they are about 300w

https://www.amazon.com/s/?ie=UTF8&keywords=12v+dc+to+ac+converter&tag=pfamazon01-20

Product description
Size:300WConverts DC 12V to AC 110V

• Dual AC Outlets
• Dual USB Ports
• This product is for DC 12V only, do not apply to DC 24V.

Specification:

• Output voltage: 110V ~ 120V AC
• Input voltage: DC 12V (10 ~ 15V)
• Rated Power: 300W
• Max. Power: 350W
• Peak Power: 600W
• USB Output: 5V/2.1A
• Ambient operating temperature range: 14°F - 140°F(-10°C - 40°C)

Safety Instruction

1. This product is for DC 12V only, do not apply to DC 24V.
2. DO NOT use with any appliance with dangerous voltage warning.
3. Plug the cord into your car AFTER the car starts
4. Do not leave the power inverter in the ON position while your car is off.

Attentions After Use:

1. Turn Off the power of the appliances
2. Pull out the AC/USB plug from the AC/USB sockets
3. Pull out the cigarette lighter after use

 

[russ_watters]

I am thinking there is about 1/2 kilowatt hour of usable electricity in an 800 cca 12 volt car battery after conversion is this right?

According to google, a standard car battery has a capacity of about 45 amp-hours. Not including inefficiency of conversion, that's 45*12/1000=0.5 kWh.

So yeah...

 

[CWatters]

When I started flying electric powered model aircraft I used ordinary car batteries to charge the flight pack. I managed to kill a few car batteries by partly discharging them and forgetting to recharge them for a few days. Used like that they only lasted about a season/year. Even deep discharge batteries weren't much better. Eventually I got a car battery charger with a float setting and got quite religious about putting the car battery back on charge as soon as I got home and leaving on the float until it was needed. Used like that they lasted about three times longer.

In short my advice would be to avoid deep discharging the battery and try and keep it on a float charger when not in use.

 

[sophiecentaur]

In short my advice would be to avoid deep discharging the battery

Alternatively use a different type of battery that is more resistant to abuse and doesn't mind being discharged. Lead acid is excellent in many ways but the deep discharge problem can be a real problem. Once they're dead they're really dead.