OK...Disclaimer: what I'm about to do could be dangerous Don't get any ideas from this unless you know what you're doing (moreso than myself to a high degree) OK, that being out of the way, let me provide a bit of background, and the supplies that I have currently, and why I would want to do something so stupid. I have made a UPS system much like <a href="http://www.dansdata.com/diyups.htm"> The DIY (or, if you must, "Ghetto") UPS</a>. Except that I have used an AGM sealed, closed valve self regulated, deep cycle marine battery. I also have 2 chargers, both of which turn off every X amount of hours. They are both sufficient to charge the battery faster than it is being used, before they shutoff after X amount of time. I want to put them on a timer that will shut them off and turn them back on, effectively resetting them, every Y hours. Upon turning on, they only work at 2 amps, for safety's sake. The load on this battery is somewhere around 4 amps, give or take an amp. So, I would like to hook these chargers up in parallel on the battery - I need have the collective amperage, but keep the voltage low, or I'll boil my battery, or worse... Another catch; it is possible that both of these chargers will vary in voltage slightly (by somewhere around 2 volts), and I'm worried that it might effectively feed backwards into the charger with the lower voltage. How in the world do I go about doing this? Can I just connect the alligator clips from each charger directly to the posts on the battery, or do I need to connect both of the pos. clips to a single wire, and attach that to the pos. terminal, and then do the same for the neg. leads? Will different voltages from each charger be a problem? I imagine that the DC will follow the path of least resistance, so, if the battery and the first charger both have higher voltages than the second charger, it all pushes flat back through the second charger and either blows an internal fuse, or worse. Any ideas?