18V ONE+ 2AH LITHIUM HIGH PERFORMANCE BATTERY - RYOBI Tools
If you use Ryobi 18V tools, this is an incredible deal. Six 2Ah batteries and charger for $129. Could be useful with the 18V inverter for small device backup power. Found at
RYOBI ONE+ 18V Lithium-Ion 2.0 Ah Compact Battery and Charger Starter Kit PSK005 - The Home Depot
USB LITHIUM 2AH LITHIUM RECHARGEABLE BATTERY - RYOBI Tools