Field tile sump pump


New Member
Other than a small solar panel with charge controller to keep some liquid transfer pump batteries charged I have 0 experience with solar powered anything. That being said, I saw a video on YouTube from a guy setting up an inexpensive solar pump and bilge pump in Africa to supply water to a nearby village. Sparked my interest so here is my setup...

I bought a 12v 18 amp bilge pump and 2 12v 100 watt solar panels that are in parellel. No battery so obviously shuts off when there isn’t sunlight and kicks off and on until there is enough amps to keep the pump rolling (usually by 9:30am). I am willing to bite the bullet on a lithium battery or two so my question is how do I protect them and make them last as long as possible. The pump is large enough to keep up with flow and will probably be off for a few hours every day while reservoir fills with water and reaches the second float of my double float switch. I say that so you don’t think it’s running at 18 amps for 24 hours straight. I found a voltage cutoff switch that I’d set for like 35 percent capacity of the battery and the charge controller would protect from overcharging right? Thanks for any advice I’ll attach pictures of what I have so far and the cutoff switch I’m thinking I need, but you tel me. Thanks!


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making mistakes so you don't have to...
The charge controller will prevent the whole pack from getting overcharged, not the 4 individual cells. You need BMS for this.

I see snow?
LiFePO4 doesn't like sub zero temperature...

You might need to get a DC hatching blanket to prevent the cells from freezing.
(Usually the cheapest solution that works great)