Best Battery Type for a Small Off-Grid Homestead?

[lyrawinslow]

Hey Everyone,

I am attempting to completely go off the grid with my little homestead and chicken house since my local power regularly cuts off even to do the smallest things.

I already installed the solar panels, but now I am even stuck with the right kind of batteries. Sellers continue to market AGM batteries, but these are expensive and I doubt they will make a good long-term purchase.

What I actually need to run:
– coop lighting and some fans at night.
– a little water pump to the birds in the daytime.
– a fridge that stays on 24/7
– and sometimes some little furnishings.

Any cheaper and still good alternatives?

 

[Debbie292d]

What we currently use to run our camper furnace, lights, and small DC fridge, etc., is two deep-cycle marine batteries. We got ours at Walmart. They supposedly last 10 years, but we've had them for two.

As for how many you'd need, there's a calculator we found to figure it out, but I'd think two would work for you, too, provided you get ample sun.

 

[Theurbanhomestead]

Hey Everyone,

I am attempting to completely go off the grid with my little homestead and chicken house since my local power regularly cuts off even to do the smallest things.

I already installed the solar panels, but now I am even stuck with the right kind of batteries. Sellers continue to market AGM batteries, but these are expensive and I doubt they will make a good long-term purchase.

What I actually need to run:
– coop lighting and some fans at night.
– a little water pump to the birds in the daytime.
– a fridge that stays on 24/7
– and sometimes some little furnishings.

Any cheaper and still good alternatives?

Just a few things off the top of my head. You really don't need a AGM battery for this because they are not moving a lot. AGM is just a lead acid battery that can be shifted around without the acid sloshing so I would not pay extra for that.

Some things that would help as far as suggestions, are you running an inverter to get to 120v (I'm assuming you are in the US if not then are you using something to get to a higher voltage). What is the voltage/wattage of the solar panels because this will make a difference in the voltage of the battery you need.

You should definitely look at how many amp hours or watt hours you are using depending on how you want to calculate things. This will give you the size of the batteries you need as far as amp hours. This can help you decide if you want multiple batteries or one bigger one.

As for battery chemistry its really up to you. All of them have some advantages.
- Lead acid: good if you get a deep cycle and they are often cheaper. The downside is they are heavy and may no last as long as some other chemistries.
- Li-ion: Prices on these have dropped a lot and they are really energy dense so you get a lot more storage for the size/weight. Most have a built in BMS (Battery management system) that keeps them from discharging to much and messing up the battery.
- LiFePO4: I really like these things. They have a good energy to weight ratio (a little less then Li-ion). They are great for off grid, I have some, and are reliable. They also come with a BMS to keep them from getting easily messed up. Most of them are good for something like a 3000 - 5000 charge/discharge cycles. They are also one of the only batteries that deal with colder temperatures as well.

Anyway I hope that helps some and I can try to answer any other questions. I am by no means an expert so if someone has better advice please correct me, I have just built a few small systems myself.

Quick edit: I am not trying to advertise or anything like that but I have had 2 of these guys for the last 3 years and have been happy with them: DC House 12v LiFePO4