Eco-Worthy Li-Fe-PO4 batteries at good prices with coupon code

I saw this on slickdeals and thought others would be interested:

Examples (prices after code SPRINGSAVE20):
12V 10Ah LiFePO4 Battery $28.55
12V 30Ah LiFePO4 Battery for RV / Boat $63.86
12V 50Ah LiFePO4 Battery $95.99
12V 100Ah LiFePO4 Battery $159.99
2-Pack 12V 50Ah LiFePO4 Batteries $191.99
12V 150Ah LiFePO4 Battery w/ Metal Case $239.99
24V 100Ah LiFePO4 Battery $359.99
48V 4-Pack 12V 50Ah LiFePO4 Batteries $383.99
& More

The biggest batteries are pushing 15 cents a watt-hour which is a lot lower than the last time I shopped for LiFePO4s.