Charging the Trident - can it be done via a car charger?

Can the Trident be charged by plugging into a 12v charging outlet, for example on a boat (cigarette lighter)? We will be doing most of our work offshore for extended periods, so will be limited to charging via the available 12v batteries on the vessels. Can the Trident be charged in this way? Only a wall charger is provided with the Trident, can it be plugged into a 12v outlet with an alternative wire?

I just use a inverter on the boat.

Thanks. Have you found a particular watt output that works best?