Batteries and the charging wires leading to them regulate the amps they can accept. AGM batteries can accept more. The dangerous part is the voltage regulation. If the volts are too high then batteries can accept more amps, and heat up to dangerous temperatures, offgassing. With AGM's there is the threat of thermal runaway with too powerful a charger. With a voltage regulated charger, the amps are going to taper quickly once the voltage gets up in the mid 14 range. With a powerful manual charger, then the volts can climb too high while the charger keeps dumping amps into the battery, heating it up, spewing hydrogen and oxygen.<br /><br />Slow charging batteries is less dangerous of course, but if one is running a generator, get them up to 80% quick as they can take it with an automatic battery charger and that will use less fuel and make less noise and disturb fewer beings in the area. As long as the voltage does not climb above ~14.8 there is little danger. Fast charges are not great for the life of the battery but so is living life chronically undercharged because one does not have a powerful enough charger and enough time to top them off.<br /><br /> Charging from 80 to 100% State Of Charge is going to take longer than from 30 to 80% SOC, as the batteries can only accept a small percentage of their amp hour capacity when above 80% SOC. As long as the voltage does not get too high there is little worry. You can't feed 60 amps into a hundred amp hour battery nearing full charge without the voltage and temperature skyrocketing. Finding a charger on a shelf today which can do this is a challenge.<br /><br />Best to have the genny and a powerful battery charger/ converter get them to near 80% in the morning and have solar to take them the rest of the way, silently, but better to have enough solar to not need the genny. Hard to fit enough solar on a Van roof though. Depends on how much power you use.<br /><br />It is easier to conserve electricity than to create it. I've seen a lot of wishful approaches on this and other forums by those unwilling to compromise electrically. They think they need x amount of power, and that is usually 50% conservative, then look for ways to make and Store that much energy. In many cases it would require a trailer filled with batteries and slathered on four sides with solar panels.<br /><br /> Many times learning to live off battery power requires realizing just how much electricity a stick and brick existence requires. This can be a slap in the face when one realizes a toaster toasting 2 slices of bread might consume a significant portion of that huge heavy battery one spent a hundred dollars for and died prematurely because one does not have the proper means to recharge it, and was not aware the battery was chronically undercharged in the first place.<br /><br /> Then one eventually learns how to fry bread, make coffee with propane, forego the microwave, turn down the screen brightness on the laptop, and learn to like the Blue white light of LED lights. After learning this on can visit friends and cringe when when they leave the fridge door open for 5 minutes while making a meal, fills the sink with water just to drain it all out unused, and leaves every light on in every room, all because grid power electricity is cheap and they never had to conserve electricity before. My friend's wife practically brags how wasteful she can afford to be, I take pride in how little electricity I need. I can't count the times I've gotten up and shut the fridge door and turned off the faucet just left running.<br /><br />The unregulated output of the honda generator is dangerous, because it will just keep forcing more and more into the battery as the voltage keeps rising. Many in the know use this output to equalize the batteries. This is an intentional overcharge to bring all the cells in the battery to the same high level. The batteries need to be monitored closely for temperature rise, and the charge should be terminated before they reach 120f or when the specific Gravity stops rising. Obviously this is not just a set it and forget it setting. Some automatic chargers have an EQ function, but they should still be monitored. <br /><br />Most batteries have a recommended maximum charge rate, like C/5. IE, a 100 amp hour Capacity battery should not be charged above 20 amps to start with.<br /><br />c/10 is safer if you have the time<br />c/50 is a trickle charge for those with too much time<br />c/2 are for those with AGM batteries, and little time.<br /><br />With solar you want 7 to 13 amps of solar panel for each hundred amp hours of battery capacity.
