Best bang for buck battery

The Watercooler
#1

Right now, the eco flow 12v 100ah battery is selling for $200, it says it has 6000+ cycles to 80%, and can pull 1800 watts, and it says 16 batteries can be used in parallel.

Before inverter or charge controllers, which are extremely cheap, it would cost 2.6c/kwh to store to 6000 cycles. That’s extremely cheap. It’s extremely easy to hook up a charge controller and inverter and a few solar panels. The only thing I am not sure on is the amount you can use with charge controllers, like if you have 16 batteries in parallel, can you have more charge controllers up to the rated combined amps from the charge controller? Hopefully someone can fill in the blanks with that.

Solar panels where I live are 33c a watt that I can get from in store, however the battery at my local eco flow website is double the price compared to the US site (factoring for currency difference) which is a bummer. Really you could get a lifetime price of 5-6c/kw stored and used when you factor in the other cheap parts. Just a thought

#2

The only good batteries like this I can get for the same USD price in my area is the Wattcycle 100ah 12v mini.

I need some for my pumps. So I am going to get 4 and put them in series.

The only thing is I am not sure if I could put 4 X 4 in series like the Ecoflow says they can.

If so, my build for a miner would look like this (Prices in AUD)

32 X wattcycle 100ah 12v mini: $280 each = $8960

2 X 48v 100ah mttp charge controllers: $242 each = $484 DC MONT 100A 12V/24V/36V/48V MPPT Solar Charge Controller - Built-in Bluetooth Backlit LCD Display, Solar Panel Regulator Compatible with Flooded AGM Gel Lithium-ion Battery : Amazon.com.au: Sports, Fitness & Outdoors

16 X greenbanks 550 watt panels: $330 each = $5280

Total: $14,724

USD = $9686

For 8.8kw of solar and 41kw of battery storage. This would suit me well as an example

Edit: this would be good for people who have very cheap off peak rates or an existing solar setup, to keep the batteries charged from the wall and to schedule the charger to turn off at X time based on your solar production or off peak rates

Second edit: if using off peak the batteries generally won’t have to be as big because generally depending on the plan, off peak hours are generally 12am - 6am and then 10am - 2pm, so a 3kw miner would need batteries I mentioned above.

Then, the price per day would be only 42kw discharge from the battery, so say 2.6c X 42 = $1.10 from the battery cost + 72 X your off peak rates. If you’re paying 3c off peak it would be $2.16 + $1.10 would be $3.16 per day for a 3kw miner which is under 4.5c/kw.

I also forgot to price in an inverter, but doing that for 14 hours off grid with off peak and inverter would cost

$400 usd for 2 X 48v to 240v 3000 watt inverters
$4400 for 24 batteries

Also ideal for someone renting

And this is all good as long as there’s no issues with inverters or batteries :rofl:

Last edit: for context, my rates are midnight - 6am 5.5c usd and 10.30am-1.30pm is free.

So pay for 6 hours + 5 hours worth of charge (an extra hour of charge not to flatten batteries) is $1.80 per day before battery cost. Because you’d probably use 2 cycles per day, my battery cost would be $2.20 per day, bringing my total cost to $4 per day, bringing my true price per kw to 5.5c usd

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