Best AGM battery for deep cycling?

I was recently out on a job at a site and the customer had several battery backup UPS units which I highly suggest. Most of these come from the factory with a small AGM battery installed inside. Some of the higher end ones use lithium these days as well. Anyway, the internal battery had died so the customer removed it and connected a large AGM battery externally for extra reserve capacity. I thought this was a great idea and want to do it myself.

The battery he used was just a basic starting AGM battery from a parts store or Wal-Mart and not a marine or deep cycle unit. I see some AGM batteries designed for deep cycle and starting which I assume are somewhat of a compromise battery. I also see them for deep cycling although the cranking amps are lower which I assume is the type I would want for a power backup unit.

Of course these UPS units are specified for AGM so the charging profile will be the same although it will take them quite a while to charge a much larger battery than what came in the unit. I would also not want to use a flooded deep cycle indoors as they release small amounts of acid in the vapor.

Any opinions on the battery type of brand? Bigger is better as this thing will be stationary. It also looks like this will need to come from a sporting goods store more like Bass Pro or a medical supplies place (wheelchair/scooter batteries) rather than a normal parts store that sells starting batteries.

Interesting thought, My preference would be to buy a bigger ups rather than spend money on an external battery, if only for aesthetic purposes. We had a company we bought ours in bulk from, 70 or so at a time, I don’t recall the brand.

I have a closet I can put this in so it will be out of sight, out of mind. I can’t imagine how long this thing could run with a battery that large. I could probably put two UPS units in parallel off a battery this large as well.

Buy a deep cycle AGM battery. No spill, no gas, totally sealed. I like Optima, their Blue Tops are deep cycle marine.

If you want better life, choose LiPo deep cycle batteries. More expensive but they don’t lose charge like an AGM just sitting around… and that is what a UPS battery does, right?

UPS batteries are maintained by ac voltage. (converted to dc of course)

They may be maintained by AC supply but they still degrade faster than lithium based battieries.

We changed our ups batteries every 3 years or so. Internet says Lithium batteries have 3x lifetime expectancy over other batteries. Do they make lithium batteries for cars?

They do make lithium batteries for cars. They are expensive.

But this thread is about UPS batteries, isn’t it?

The op was talking about using a car battery to power the UPS.

You can buy deep cycle batteries in the same physical size as car batteries. Bigger and smaller, too. Boat batteries, trolling motors, RV batteries are all deep cycle. You can get them at AutoZone or WalMart or Rural King or Batteries Plus.

I put three in a couple years ago or so. One at the router and wifi, one at my computer, and one for the wife’s. I think they recommended changing the batteries every 3 years. I don’t expect them to last long in a power failure, but I like the idea of clean power in addition.

Way back the IT folks were complaining about having computer problems and whatever they claimed was the reason made no sense. We said they needed a UPS and they said they didn’t. We put a huge one in as big as a refrigerator anyway to run all their computer systems. Problem solved. In true jerk fashion, they never said another word. If I remember right, we traced it to when a building pump came on, created enough of a power spike to cause problems.

So I’m a fan of them and if you would check the voltage fluctuations in normal house current, I think you’d be surprised how much variation there is. OK for coffee pots but not computers.

I hear you, our new refrigerator is a computer in itself, wifi, cell app, screen display etc. no ups but definately a surge protector added. Think I’ll add one for the washer and dryer, many electric push buttons and circuit boards I am sure!
I hope in the future a 3k refridge will have a surge protector built in, called support our LG does not.

UPS batteries are constantly maintained at full charge so discharge isn’t an issue unless the power goes off. LiPo, or LiPoFe, or whatever charge differently so I would need a UPS designed around that battery chemistry and its charging characteristics.

I will look at the blue tops. I know these things are not cheap but if they last longer, I am all for it.

It looks like BLUE TOPS come in two different flavors. There is a dark gray case and a light gray. Light gray is what I would want.

UPS units really work wonders for cleaning up dirty power from brownouts and surges. Pumps kicking on create nasty brownouts. I tell people a UPS is worth its weight in lead since most of the batteries are lead-based like the AGM in question.

I want to stick with AGM as the UPS units in question are built around that type of battery. Some of the newer lithium stuff is really good as well.

All the electronics in appliances drive me nuts. Working with computers, I realize that this stuff seems to experience a much greater failure rate after 3-5 years of service life. I have seen so many appliances scrapped because of a board failure, not an actual failure of the compressor, motor, heating element, or whatever really does the heavy lifting inside the unit. The parts are either not available or cost nearly as much as a new unit.

The same applies to cars. I know a lot of horror stories about dashes going completely out when these newer electronics became common for everything being built in but it seems like these have been perfected. I don’t hear near the complaints about them in more recent models so that is a good thing as they are so common.

A lot of the car shortages are related to chips for the dash, etc., not engine and transmission management, etc. Why not just make a basic model car without all this stuff if they can get the parts that allow it to go down the road? Another option would be to sell a model with a basic dash or some features completely missing with a guarantee that eventually a dash could be swapped in with all the features people want for free or a guaranteed price of some kind? If the dash costs $1200 to install or whatever, just knock $1200 off the car. People can either drive it the way it comes forever or get in line and get the dash they really want for $1200 down the road. Of course that price is probably low but I threw it out.

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Be aware though that all UPSs are not equal.

I always suggest line-interactive types unless the equipment is really mission critical. I don’t think you can even get the most basic standby only ones anymore.

Still around. And the next step up from line-interactive starts at a bout a grand. So line-interactive would be most folks best choice.

I have heard that cars used to succumb to static electricity (old Mosfets I think) I gather that is less of a problem now.