In short, For 1500 watt inverter you'll need two 12V 100Ah lead-acid batteries connected in series or a single 24V 100Ah lithium battery to run your 1500W inverter at its full capacity. the lead-acid batteries should be two because of their C-ratings. So in this guide, you'll find out what size and voltage battery you should use with your 1500W inverter, How " many" batteries you should use (single or multiple batteries connected to each other), and also what size cable will be suitable for you. Typically, you will need batteries that can provide sufficient amp-hours to meet your power demands.
[PDF Version]
