solar controller for 52 v. battery and single pv panel

The closet I can find is this Genesun :https://genasun.com/all-products/solar-charge-controllers/for-lithium/gv-boost-waterproof-105-350w-solar-golf-cart-boost-charge-controller-with-mppt-lithium/ Fine and dandy, perfect with it's ability of jacking the voltage up from a SINGLE panel up higher while also controlling,even IF I had a 48 volt battery. Sure it'd be better then nothing, state of charge wise, and at least get me up to the mid 50's but if I'm going to go to the trouble, weight, and expense of mounting a 120 watt it sure would be nice to fully charge my 52 v. battery. I wonder if that controller can be be somehow fooled to go a bit higher voltage?

I have room on the plane's cockpit roof for one, and one only, 100 to 120 watt panel. Maybe I should look into 3 50 watt panels in series and just hand control it? That would be a bit more problematic in making them fit, but possible with a little extra work. That's also save the weight and expense of a controller. But then, as I want to also use any add on PV to the plane to also serve as a 12 volt battery charger to offset my use of the SIRIUS radio when camped, I'd then have to get a converter to lower the panel's higher voltage.

As to how much power a single, let's call it 100 watts, panel would put into my 52 system, I guesstimate about 1.5 amps at best. 100 watts divided by 56 v. bulk charge rate is the way I arrived at that number. This is not counting any gains by the MPPT thing, I'd probably see more when the battery was deeply discharged and it was cold. But using the 1.5 amp figure, a real low (but safe) charge rate for my 11.5 AH battery, I'd still get (not counting losses but in theory) about 3 or 4 more miles down the rode for every hour charging. 1.5 x 52 = 78 watts, about 20 watts per mile. Feel free anyone to correct my math. My use would be to be able to throw a small, "better then nothing", charge into the battery while I fly along, plus of course while camped out, and to also have a back up charge source for my plane's 12 v system as mentioned.

According to the link you've got there, it will go up to:

8A 56.8V (LiFePO4) MPPT Controller

Click to expand...

Is 52V the max charge voltage for your battery? Or is it 56V? Or something else? (you don't specify in your post).

When charging to 100% with my Luna charger, it goes up to 58.4 or .7. My concern was once getting much over 48 v, the controller would start backing off the charge rate, taking even longer. Maybe it allows full current right up to 56'ish, losing those extra watts by not getting up to 58 + v would bug me, but I guess I could live with it. I may try and get a real live person at Genasun to bounce the idea off.

Purely from a weight and simplicity viewpoint, after some further thought, rather then solar I am again going to play around with one of these DC-DC converters (this one has a digital readout, I'm not sure if it'll show output or input as there are no instructions) to recharge my bike battery while flying. Mounting 3 50 watt flex solar panels to the top of the plane would work, but the weight when not needed would be a "downer", it's not good for any aircraft to have dead weight when not needed. Mounting the panels correctly, to make damn sure they didn't blow off, would pretty much preclude make them quickly removable. Any rack system to possibly do so would, again, add additional weight, drag, and complexity. This (buck converter I think they are called?) is lightweight and I can even make it quickly unpluggable so I don't have to haul it around when not needed.

Last night I was in a motel room in Kalispell Montana, and as I plugged into the room's wall plug, I realized this was the first time in over 500 miles of riding I have NOT used my home solar system to recharge. The plane engine as a recharge source isn't a free ride either, it will be interesting to see, assuming I don't fry this converter like I did the first one, if I can see a hit on the pretty sensitive and accurate fuel flow indicator OR the air speed indicator when I put a 10 amp draw on the engine Today, while flying 100 mph ground speed (in a straight line least we forget) I was burning 3.3 GPH of regular/low octane car gas, E-10. That kind of economy is what makes flying feasible for me, and I don't want to mess with that.

On a side note:flying back this AM through some real inclement weather, scattered thunderstorms etc., it was as always comforting to know that if I had to set down somewhere and wait out weather, having the e bike on board would make a huge difference as in getting to someplace to eat or whatever instead of being stuck out in the boonies somewhere. A major thread drift, but it's my thread, :lol: if I get the buck converter to work out I'll start another thread for it. On a related note, I used my cheap 400 watt 12 volt inverter plugged into my beefed up (to handle the amp draw) dc outlet in my Yaris to recharge the other day while driving across the desert. If I was at idle, my inverter low voltage alarm went off, as soon as I started driving all was well. So, making AC out of DC, and then converting it back to DC via the 3 amp setting with the Luna charger, is a pretty inefficient process, though workable. Better to keep it DC/DC.