It's getting to be that time of year again. What do like? There must 50 different ones on Amazon. There seems to be new more advanced models every year. Are any of their claims valid Or just snake oil advertising hype? Are they really any better than any old 2 amp charger? If you have 2 or more batteries in a vehicle does each one need a dedicated trickle charger or can they be charged in parallel?
Thanks.

In theory, there is no difference between theory and practice. In practice, there is.