Battery Life - 12V Inverter

[nickelflippr]

For my travel trailer, the house battery on my boat, backup power for my ham station, I use 100Ah Sealed Lead Acid (AGM) batteries designed for UPS service. I happen to have a source of these that are removed from commercial service after they get two years old. They typically have a capacity of about 85Ah when I get them. I use them for about three years and discard them when their capacity goes below ~50Ah. To get three years, I constantly float them per the manufacturer's instructions (13.5V to 13.8V, depending on ambient temperature), other wise, just sitting around, they go dead in six months to a year, and cannot be recovered.

Check with local government or businesses that have standby power systems. For critical applications, they routinely remove from service batteries that still have a lot of useful life for a hobbyist.

Curious as to the manufacturer and model no. of your UPS batteries. If I could be so bold as to ask; are they from a telecom co.? and how much did they cost? Five years of service is very good for deep discharges, more than double probably than a standard flooded lead acid battery.

I have a 100ah Deka AGM battery in the pickup camper and it has a very low discharge rate. It was bought new and cost an arm and a leg. Left the battery in a full charge condition 4mos. ago (about 12.9V). After reconnecting the battery, turned on the hood fan for a couple of minutes. Rechecked the battery voltage and it was 12.6V. Normally, they should have a very good shelf life, or low self discharge rate.

 

[Levi Camias]

Can i have a diagram?

 

[Levi Camias]

is there a cheapest inverter?