https://www.ebay.com/itm/XXX/127522959463?mkevt=1&mkcid=1&mkrid=711-53200-19255-0&campid=53372598 ECO-WORTHY 48V 100Ah Lithium LiFePO4 Stacked Style Battery on sale for $799.99 - $160 when you apply coupon code CYBERWEEK20 at checkout = $639.99. Shipping is free.