We would like to find a trickle charger that works with a pig tail and can be left on without over heating the battery or concerns for the electrical system.
Personally I have had great luck with my Battery Tender Jr. I only use it in the winter when my vehicle is in storage, but the batteries have always been ready for the first spring drive.
Here is the one I use- Battery Tender Jr.
I use the same one. Great unit for the price, I’ve had great luck with the ‘Battery Tender’ brand. I keep one on my car and one on my wife’s scooter all winter.
I, too, use the Battery Tender Jr on all my stuff. The only time I’ve had a problem is when one of the clamps touched sheetmetal and left a mark from the arcing. Since then I use the pigtails on everything. On our old comments system, some readers insisted that you remove a battery before hooking up to any trickle charger to reduce the risk of electrical fire. That’s not really practical for applications like a moped (a short trip might not recharge the battery loss from starting), but I’d say whatever you try, read the instructions carefully.
the key is to have the right charger for the battery you are charging. meaning there is a difference in the chargers based on Lead Acid, AGM and Lithium. make sure the charger matches. so for instance a Battery Tender Plus doesn’t work with a Lithium battery. it will charge but will damage the battery (battery turns into a balloon). After that Battery Tender, Associated and Schumacher are all good choices. Avoid the real cheap ones.
I have three different trickle chargers, including the Battery Tender. The one I like best is from Granite Digital. It has an indestructible case, clear readouts and heavy duty cables. It is my pick every time now that I am down to just one old car.
I second all those that use a Battery Tender Jr. Super cheap and effective. I use two all winter.
I will join the Battery Tender chorus. Mine are the Battery Tender Plus. I leave them on my cars whenever they are garaged. Have never had a problem with the units overheating or overcharging. And yes, they do have a pigtail plug.