UPS batteries a cautionary tale

[peakbagger]

Many pellet folks appear to back up their power with computer type UPS units. They usually have several sealed batteries that are maintenance free in side the case. The unit I use on my office equipment is one of these style. Last week after coming back home to my house I smelled an odd odor in my home office. I traced it to an APC UPS. It was easy to trace as the unit was beeping and lights were flashing. I went to touch the units case and it was very hot to the touch. I quickly unplugged it and pulled the disconnect jumper from the back. I finally had a chance to open up the UPS this morning . The two battery cases were swelled up on the top and all four sides with the two batteries stuck together. In some spots the case had expanded as much as 1" It took me a bit to pry them out of the frame as they swelled into the gaps in the frame. I had a pair of spare batteries so I installed them and the UPS seems to be working correctly. No trace of battery acid.

There was no damage to the surroundings but I expect there could have been. These batteries were about time for replacement, but the last time I was given some front end warning during the automatic tests and shut it down when it indicated it had lost capacity. I was given no warning this time. It was working properly the day before with no beeps or warnings.

This UPS is known generally quality brand (APC smart UPS 1000).

I would suggest that if you do run a UPS that you probably keep it on a non combustible surface and definitely not cover it with anything.

 

[Wilbur Feral]

Excellent advice.

 

[SXIPro]

I would contact APC. I bet they would replace the entire unit even if it were beyond the warranty period.

 

[bogieb]

Hmm, have to do something with the one for the St. Croix - it's on a hard wood floor because I figured I want to keep it away from the stove. I guess I should be able to place it behind the stove on the hearth pad.

 

[TimfromMA]

Hmm, have to do something with the one for the St. Croix - it's on a hard wood floor because I figured I want to keep it away from the stove. I guess I should be able to place it behind the stove on the hearth pad.

These batteries can produce hydrogen when charging. That aside, It need to be able to keep cool so putting it near the stove may increase the chance of it overheating.

 

[bogieb]

These batteries can produce hydrogen when charging. That aside, It need to be able to keep cool so putting it near the stove may increase the chance of it overheating.

Under the stove stays cool and the OAK probably keeps the back even cooler (will have to check). But yeah - that was the main reason for my placing it away from the stove and on the hardwood to begin with. damned if I do, and damned if I don't I guess.

 

[peakbagger]

Here is a photo of one of the batterys

 

[bobdog2o02]

These types of SLA(Sealed lead acid), and AGM( absorbed glass mat) are heavily used in the alarm and emergency light industries. The suggested life is 4 years, I've seen them fail as early as 2 years when they aren't charged properly. I would recommend pulling the a/c cord at the beggining of the season and midway through for a half hour or so to make sure the batteries are actually in good condition. Most APC units I've had experience with didn't give a battery alarm until the batteries actually ruptured like yours.

FYI that genesis battery is the bottom of the barrel, replace with Eagle Picher if you can find them. They'll last 2-3 times as long.

 

[peakbagger]

Thanks for the info. I actually had two more of the genesis batteries in stock that were never installed so they got installed at least for the short term. The batteries that failed have rode through several power outages in the last few years. If I am in the office and power goes out I usually shut everything down rather then running until the UPS runs out of juice

 

[gfreek]

These batteries can produce hydrogen when charging.

Aren't these sealed batteries thus no hydrogen gas when charged or is there a small vent somewhere ?

 

[bobdog2o02]

Aren't these sealed batteries thus no hydrogen gas when charged or is there a small vent somewhere ?

They are sealed, when they start to fail heat is generated the heat softns the plastic and the gass build up swells the case. If it doesn't tear it will explode. These things should be inspected regularly.

 

[BrotherBart]

Aren't these sealed batteries thus no hydrogen gas when charged or is there a small vent somewhere ?

They are Valve Regulated Lead Acid batteries. They do have a vent if pressure gets high enough. But have also been known to rupture due to overcharging/overheating.

 

[Harvey Schneider]

Many pellet folks appear to back up their power with computer type UPS units. They usually have several sealed batteries that are maintenance free in side the case. The unit I use on my office equipment is one of these style. Last week after coming back home to my house I smelled an odd odor in my home office. I traced it to an APC UPS. It was easy to trace as the unit was beeping and lights were flashing. I went to touch the units case and it was very hot to the touch. I quickly unplugged it and pulled the disconnect jumper from the back. I finally had a chance to open up the UPS this morning . The two battery cases were swelled up on the top and all four sides with the two batteries stuck together. In some spots the case had expanded as much as 1" It took me a bit to pry them out of the frame as they swelled into the gaps in the frame. I had a pair of spare batteries so I installed them and the UPS seems to be working correctly. No trace of battery acid.

There was no damage to the surroundings but I expect there could have been. These batteries were about time for replacement, but the last time I was given some front end warning during the automatic tests and shut it down when it indicated it had lost capacity. I was given no warning this time. It was working properly the day before with no beeps or warnings.

This UPS is known generally quality brand (APC smart UPS 1000).

I would suggest that if you do run a UPS that you probably keep it on a non combustible surface and definitely not cover it with anything.

It sounds as if the battery had a shorted cell and the charger thought it was just a battery in a low charge state. The problem is that many "dumb" battery charging circuits can't tell the difference. That leads to severe overcharging for the remaining cells in the battery. Any battery when overcharged produces hydrogen gas. Sealed batteries have a catalyst in them that recombines the hydrogen with oxygen up to a point. When the gas generation exceeds the capacity of the catalyst, the cell is supposed to vent so that it doesn't rupture.
Since none of these safety features ever gets tested, you don't know that they have failed until they don't provide the funtion they are designed to do.
By the way, charging batteries of any kind should always be on a non flamable surface.

 

[SidecarFlip]

Just get a propane or NG fired standby genny and call it good.

 

[TimfromMA]

Theres no NG on my street.

 

[SidecarFlip]

Theres no NG on my street.

Got propane? Got oil? My next one will be an oil (diesel) fueled standby.

 

[SidecarFlip]

My view is what good is a stove running with nothing else working. You might say warm, but not for long because the UPS won't last very long and then, it's cold and dark too.

Being the good neighbor I am, I have a 50 amp twistlock on the side of the house so the folks across the road can share my standby if necessary.......

 

[TimfromMA]

I got a portable gas generator plus a modified APC that can run my stove for 8 hours.

 

[SidecarFlip]

That works, for you. Myself, I like it to be as close to utility power as possible, I'm old and starting a portable genny ain't in my cards.

 

[Wilbur Feral]

Being the good neighbor I am, I have a 50 amp twistlock on the side of the house so the folks across the road can share my standby if necessary.......

Have to hope that road has a light amount of traffic!

 

[BrotherBart]

That works, for you. Myself, I like it to be as close to utility power as possible, I'm old and starting a portable genny ain't in my cards.

I am old and feeding a whole house unit ain't in my budget. Two portables in the shed corded into the house and 800ah of batteries and inverter power in the basement just has to do. Run the gennies in the daytime and go on battery at night. Year after year after year...

And just run the wood burner when power is out.

 

[bogieb]

My view is what good is a stove running with nothing else working. You might say warm, but not for long because the UPS won't last very long and then, it's cold and dark too.

Being the good neighbor I am, I have a 50 amp twistlock on the side of the house so the folks across the road can share my standby if necessary.......

Don't care if the stove stays running; in fact, the Harman should shut itself down gracefully and it would give me enough time to shut down the St. Croix. Also, a lot of times, the power just goes out for only 5-15 minutes, so the backup would bridge the gap for the Hastings.

Been totally without power several times for 4-7 days. Melt snow for water in the winter, and other times fill 5 gallon jugs with water from streams. Heck, now that I live "in town" I would still have water. My cook stove is propane, and I know it would keep the main rooms warm if I needed it to (been there, done that). Candles and hurricane lanterns do fine for light. Not really tough to do without power for a while when you don't have kids. I do have a small gas generator so I could power up my phone, computer and fridge if I needed to. Of course during winter, all of outdoors is a fridge; had all of a fridge/freezer and 20 cu/ft freezer on a deck for 4 days several years ago staying cold - biggest issue was keeping the milk and mayonnaise from freezing.

 

[TimfromMA]

Shut off the noisy generator at night so you can sleep while the stove runs on battery. Fire up the generator in the morning to charge the batteries and power the house.

Rinse and repeat if necessary.

 

[ironpony]

I am old and feeding a whole house unit ain't in my budget. Two portables in the shed corded into the house and 800ah of batteries and inverter power in the basement just has to do. Run the gennies in the daytime and go on battery at night. Year after year after year...

And just run the wood burner when power is out.

come on man, you know you Need a 40kw "backup" to power the neighborhood. just think you could add meters and charge all the neighbors.