I use a small 175w inverter with a USB port. I can charge any of my personal electronics and AA battery charger through the lighter port.

The thing is you do not want to charge anything higher than a laptop through the lighter port because it isn't designed for high current continuous draw. That's why a number of high drain inverters have hard-wire connectors so that you can charge off the alternator. I can't imagine how those electric food coolers or TVs can run for very long off a lighter port unless it has an auto shut-off circuit to prevent damage to the port.

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