Batteries for 12VDC diaphragm pumps

[Cedar Eater]

I'm wondering what battery to use for my cheap diaphragm pump. The 14ah deep cycle battery that I bought won't run my pump for 24 hours, but I think that two connected in parallel will.

I don't really see any difference between batteries labeled as "deep cycle", "marine", "UPS", "SLA", and "AGM". I can pick up a cheap 26 ah battery to alternate with the paired batteries. It isn't advertised as a deep cycle battery, but it is the same SLA and AGM technology as many that are, and it is intended for wheelchairs and scooters, so I think it should work. Does anyone have any experience with these?

http://www.apexbattery.com/tempest-t...h-battery.html

[madmapler]

There's the option of going with a couple 6 volt golf cart batteries. I was told by a guy who worked at a golf cart shop that they are about the best thing going. Trojan is the name I think. They're about the size of a large car battery.... After looking back at your post, I guess it's too late to go that route.

[Cedar Eater]

The full load Amps of the pump that I'm using is only 3 Amps. That's less than 1/2 the FLA of a Shurflo and I'm certain that it doesn't operate at FLA. The cost of the pumping station is under $50 without batteries. It seems excessive to use two large heavy and expensive batteries to power that pump. Maybe if I wanted a two day run, but I'm only looking for 24 hours. So I guess I should specify that I'm looking for batteries that are under $100.

[1arch]

Some math to figure out the kWh load. P(watts)=E(Volts)xI(Amps).
Watts = 12 volts x 3Amps = 36 watts per hour. 36 x 24 hours = 864/1000 = .864kWh's. If you have access to Trojan they have specs for the 20 hour kWh rates.
Flooded lead acid cost less than a gel or AGM and have more kWh storage. Two in parallel as you mentioned will double available kWh's. Typically... 2- 6 volt batteries in series offers more kWh's than 2 -12 volt batteries in parallel. Buy a large enouph battery so you don't drain them dead or plan to buy replacements more often.