Lead Acid Battery Long life question.

[ibrar0]

Hi,

I have a UPS, with AGS Battery of 160 Ampere, But use of UPS is very rare may be 5 minutes a Day, and battery remains always full. My question is that, is it wise to discharge my battery once a month or week, will it have positive or negative effect on my battery life.

Thanks in advance.

 

[tpetar]

No, lead acid dont need to be discharged. You can discharge it 30%-40% one in 6 or 12 month just like some condition test.

Measure and monitor internal resistance from first day, periodically one time per month or on three month.

 

[BradtheRad]

If your UPS keeps it fully charged as much of the time as possible, it will have maximum useful life.

About 12.6 to 12.8 V for a 12V battery.

It should not stay discharged any longer than necessary.

It should not be overcharged...
However due to a battery's tendency to slowly self-discharge, the UPS may feed it a slight trickle current every so often.

 

[ibrar0]

If your UPS keeps it fully charged as much of the time as possible, it will have maximum useful life.

About 12.6 to 12.8 V for a 12V battery.

It should not stay discharged any longer than necessary.

It should not be overcharged...
However due to a battery's tendency to slowly self-discharge, the UPS may feed it a slight trickle current every so often.

Yes, UPS has tickle charging option, and it always keep it fully charge, Battery is always connected with UPS so, there is no point of self-discharging due to internal resistence,

I was wondering if i should use battery backup to discharge it more 50%, i thought may be its better to have discharge cycle , because I don't know chemistery & physics behind lead-acid battery.

So, finally i shouldn't discharge it, and it will have long life by this way.

Here is snap of the battery
**broken link removed**

Thanks
:grin::grin::grin:

 

[tpetar]

there is no point of self-discharging due to internal resistence,

Internal resistance is not linked with self discharging, its showing status and health of battery, this is one of indicators. If IR is high this can be indication of some physical damage inside plates or grids, maybe isolation paste fall down,....


Dont discharge lead acid complete never, specially if it is starter batteries, its also called float batteries. Max go to 11,9V of lower discharge level at 10,5V you can kill bat. For deep cycle type you can discharge it up to 10,5V point, but this type is rated for max current of C/20, its not like as starter for higher starting amperages.

:wink:

 

[BradtheRad]

It is still a good idea to test the system every so often, as tpetar suggests. It's okay to discharge it 30 or 40 percent.

That way you can make sure the battery will have enough power when you need it.

You need to find out if it's still in good condition every so often. Because it will not last forever no matter how well you treat it. That's how batteries are.

 

[tpetar]

Lots of better UPS have self test option one per 24h for several sec on batteries, like small test of system.

:wink:

 

[chuckey]

There is only one test for a UPS - switch off the mains, this way, you can make sure that not only the battery is good but that all the other electronics work as well. Make sure there is some one present who can manually switch the mains back on if it all goes pear shaped. Long yarn :- ( ) We had diesel supported local radio stations, every Wednesday, we would remotely send a controls that was meant to simulate a mains fail. Any faults that were found were then rectified. Eventually it became apparent that when all the mains was lost to the station, the diesel never started. What was happening was in the test situation, the battery charger was left with mains on it which just gave the battery enough voltage to start the diesel. When all the mains was lost, the batteries did not have enough voltage to pull in the fuel solenoid and the starter motor would just run and run until the batteries were flat. We had to rewire the battery to fuel solenoid circuit with a heavier gauge wire to cure the problem.
Frank

 

[tpetar]

For some systems with delicate roles, such this in previous post, battery should be changed periodicaly with new, let say on every 3 year, battery is changed with new, regardless is battery good or not. In any way existing cannot be better then new.

I always talking that monitoring internal resistance of lead acid is very usefull. Start monitoring from first day to see normal value, and periodically one per week/per month monitoring to see progress. This will show even sulphatisation process or any other proces such as braking of grid, plate cracking, isolation paste fall down,...

:wink:

 

[edpalmer42]

Hi,

I have a UPS, with AGS Battery of 160 Ampere, But use of UPS is very rare may be 5 minutes a Day, and battery remains always full. My question is that, is it wise to discharge my battery once a month or week, will it have positive or negative effect on my battery life.

Thanks in advance.

As others have said, routine discharging of a UPS battery doesn't really affect the life of the battery.

Since the battery you show in the picture has removable caps, make sure that you monitor the water level in the cells and add distilled water (NOT TAP WATER!) as necessary. If the charge voltage is slightly high, the water will break down into hydrogen and oxygen so make sure there's enough ventilation. If the charge voltage is too low, the battery will slowly sulfate and the capacity will be reduced. It's a delicate balance.

Ed