BATTERY BACK-UP FOR 1/3hp SUMP PUMP

I am looking into getting a battery back-up for my existing sump pump (not interested in getting a secondary one put in). The only way is usually using an inverter with automatic transfer switch with battery charger. I would also be using a deep cell marine battery but it looks like to much bulk.

I was told of a new battery back-up system that is compact and all encased. It also uses lithium ion batteries that will last a lifetime. Does anyone know of these or have seen them? The one I was told of was made by Xtreme but not sure. Thanks!

The only lithium ion batteries that will last a lifetime are the ones that have a lifetime warranty.

X-treme does have a lot of batteries and battery related items.

There is another option, as well. That's a city water powered pump. No electricity required. But of course you can't use it if you are on well water.

It's actually an eductor.
Here's a couple of examples of them.
https://www.amazon.com/Liberty-Pump...ocphy=9001930&hvtargid=pla-338104954514&psc=1

https://www.lowes.com/pd/zoeller-ho...BHk4O6FixaLviVZh_SFGF7iVHq_OS-r0aAmMzEALw_wcB

Trouble is, being connected to a city water source requires certain precautions be made to protect the city water from back flow contamination.