Telecom UPS Batteries for Solar (Deka Fahrenheit)

[Komrade]

Does anybody have any opinions for using UPS solar in Solar ?

The batteries in setups with auto-generator start (e.g. Sol-Ark) never really get drained beyond a point determined by owner (e.g. 80%)

 

[Komrade]

found an opinion in older thread

Deka AGM Batteries - Will they work?

Hello all and thank you for taking the time to read this post. Looking into building an off grid DIY solar set up and I ran across these batteries. Was wondering if they would be suitable for solar usage. Deka 12avr100et They are new but a few years old.

diysolarforum.com

Those are telecommunications "telco" batteries. Even if they are in great condition, they're not designed for frequent cycling. They are meant to spend their life sitting at float voltage with a load and charger connected...only to come in to play when there is a power outage. And even then as a UPS to keep the site up and running for a minute until the generator starts. I've worked with this type of battery for years at radio towers.

 

[Komrade]

So basically, they're good for a few minutes until generator starts if that's what I want.
and if that's what I want, I just need to make sure they can support the typical draw.

 

[v_green57]

So basically, they're good for a few minutes until generator starts if that's what I want.
and if that's what I want, I just need to make sure they can support the typical draw.

I have several in use:

Narada 12NDT190, Deka 12AVR145ET, some 130aH I don't have the model numbers handy for.

All bought by a friend of mine from these guys:

Overstock Batteries - Deep Cycle Battery Store

Inventory Updated for Overstock Batteries Here you will find all overstock batteries at a discounted price. Overstock batteries for sale are batteries removed from telecom towers and have been tested before offered for sale.The quantities available are listed and once they are gone, they are gone –

deepcyclebatterystore.com

(since he lives in S.D.) and brought up to our off-grid neighborhood.

They were all used when bought, are going strong several years later.

The 12NDT190 and 12AVR145ET are paralleled (I know, I know, not matched) and connected to a Freedom Marine 2Kw inverter in a 28' travel trailer. I daily run a 1kW hot pot (coffee!) and Samsung microwave now and then. Plus all the usual 12V trailer stuff.

I see no indication whatsoever of this:

"Even if they are in great condition, they're not designed for frequent cycling."

They have all been cycled at various loads for years.

 

[Vigo]

I suspect that in general they are tighter quality control than most lead acid of any other kind.

 

[sunshine_eggo]

The lack of an absorption voltage or cyclic application charge voltage (only float is listed), these are standby batteries. They are not designed for long cycle life. I would not expect them to work any better than automotive-type batteries in cycling applications.

They are designed to sit fully charged for very long periods of time. When called into service, they can discharge at high current, and in most cases can charge at up to 0.3C to the float voltage.

I would only consider them for a cyclic application if I got a smoking deal - 25-33% the cost of a true deep cycle battery designed for cycle life.

 

[Zwy]

Does anybody have any opinions for using UPS solar in Solar ?

The batteries in setups with auto-generator start (e.g. Sol-Ark) never really get drained beyond a point determined by owner (e.g. 80%)


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If the batteries are free, then sure.

If you are purchasing the batteries, consider moving to LFP especially if long term usage.

The biggest problem with any lead acid chemistry battery is absorption charging and inability to reach full charge to prevent sulfation. LFP is perfectly suited for a solar system, lead acid is perfectly suited for things other than solar.