Any added life to an AGM by adding water?

[Gale Hawkins]

Has anyone had any luck getting more life out of a dying AGM battery by removing the caps and adding water?

 

[marimus]

I wouldn't imagine so but worth a try right?

 

[JDgreen227]

Has anyone had any luck getting more life out of a dying AGM battery by removing the caps and adding water?

Have had a bunch of ATV AGM's go bad, and tried one time to drain the fluid inside to possibly replace it. Wouldn't drain ANYTHING. From what I understand the innards are so absorbent you cannot drain or add anything after the initial fill.

But try it. Do you mean adding WATER, or ACID?

 

[Gale Hawkins]

Water.

These are power chair batteries. The 12-55AH batteries are perhaps 10 years old and took a lot of water before the mats stopped sucking it up.

Got one up to 10.5v (dead cell) and so far 12.2v is as high of resting voltage I have gotten it to reach but I am still run Desulf Mode on the B&D charger and charging with another charger. I can see slight gassing in all 6 cells.

The two 12v-12AH batteries (never used power chair) were at 2.6v and 3.3v but would not gain from charging them so I removed the caps and they were very dry too so I added enough water to slightly flood the mats. This morning (second day of conditing) they have recovered to a resting voltage of 121v and 12.5v.

I was just wondering it one had experiences to share. I found some on the web.

adding water to agm battery - Google Search

 

[jonyyuma]

It will be interesting to see how the recovered batteries hold a charge and load testing.?

 

[JDgreen227]

Water.

These are power chair batteries. The 12-55AH batteries are perhaps 10 years old and took a lot of water before the mats stopped sucking it up.

Got one up to 10.5v (dead cell) and so far 12.2v is as high of resting voltage I have gotten it to reach but I am still run Desulf Mode on the B&D charger and charging with another charger. I can see slight gassing in all 6 cells.

The two 12v-12AH batteries (never used power chair) were at 2.6v and 3.3v but would not gain from charging them so I removed the caps and they were very dry too so I added enough water to slightly flood the mats. This morning (second day of conditing) they have recovered to a resting voltage of 121v and 12.5v.

I was just wondering it one had experiences to share. I found some on the web.

adding water to agm battery - Google Search

Thanks for the clarifications, I always think of AGM as being lower amp (like 12A) but those must be good sized batteries. Will be interesting to follow this, keep us posted. Ten years is a LONG time for any battery, especially an AGM, to be discharged.

 

[Mickey_Fx]

Personally, I've never seen an AGM that wasn't sealed. Back in the 80's when this tech was first being developped, they were called starved electrolyte batteries. There was/is no excess electrolyte. They contain just enough electrolyte for the electrochemical process to take place. I would question these batteries as being true starved-electrolyte/AGM batteries if they have removable caps.

As for adding water/electrolyte to a LA battery, acid is most concentrated when battery is full charge and lest concentrated when discharged. Depends on state of charge for acid concentration to be added. You don't want the acid concentration to be above that normally used when battery is fully charged.

The Tech was developed by Gates at their Gates Energy Products Div in Denver. I (through the Co I worked for) was an early adopter of this tech and visited Gated numerous times during that period. Gates has long gone out of the battery business.

 

[JDgreen227]

Personally, I've never seen an AGM that wasn't sealed. Back in the 80's when this tech was first being developped, they were called starved electrolyte batteries. There was/is no excess electrolyte. They contain just enough electrolyte for the electrochemical process to take place. I would question these batteries as being true starved-electrolyte/AGM batteries if they have removable caps.

As for adding water/electrolyte to a LA battery, acid is most concentrated when battery is full charge and lest concentrated when discharged. Depends on state of charge for acid concentration to be added. You don't want the acid concentration to be above that normally used when battery is fully charged.

The Tech was developed by Gates at their Gates Energy Products Div in Denver. I (through the Co I worked for) was an early adopter of this tech and visited Gated numerous times during that period. Gates has long gone out of the battery business.

By sealed, you mean no way for the user to add water or acid? The AGM batteries our ATV's use have openings on the top, they are sold dry and you add a prefilled package of water and acid to the openings, then seal the openings with a plastic strip. These are the only type of AGM battery I have ever seen. The white label on this one says:

"This is a sealed battery. The sealing caps should be considered permanent. The caps should not be removed to add water or charge the battery".

 

[Gale Hawkins]

Personally, I've never seen an AGM that wasn't sealed. Back in the 80's when this tech was first being developped, they were called starved electrolyte batteries. There was/is no excess electrolyte. They contain just enough electrolyte for the electrochemical process to take place. I would question these batteries as being true starved-electrolyte/AGM batteries if they have removable caps.

As for adding water/electrolyte to a LA battery, acid is most concentrated when battery is full charge and lest concentrated when discharged. Depends on state of charge for acid concentration to be added. You don't want the acid concentration to be above that normally used when battery is fully charged.

The Tech was developed by Gates at their Gates Energy Products Div in Denver. I (through the Co I worked for) was an early adopter of this tech and visited Gated numerous times during that period. Gates has long gone out of the battery business.

Mickey they are sealed. You have to pop off the seal to get to the caps/valves. They are just rubber caps that push on. The seal means they can not come off while the seal is in place BUT can vent gas.

Sealed does not mean sealed as in a can of tuna.

Over the years and especially if over charged they loose water like any battery. Both the 12 and 55 ah batteries are gasing when they are start reaching a full charge.

I am not sure the epsom salt (1/2 teaspoon per cell) in the 12 ah ones helped but both are over 12v now and the automatic three stage B&D charger is not longer fighting them by reporting open cells. Even the equalizing feature worked as expect with a lot of gassing which is a good sign. I may keep charging them until there is no water over the plates before I reseal them.

 

[Gale Hawkins]

With my chargers I have not been able to get the resting voltage to be greater than 12.3v in the 12ah batteries. I got one of 55ah batteries to 12.3v and pushed hard a dead cell developed.

Note these power chair batteries had set for years without charging. Making sure a battery NEVER drops below when NOT in use I think is about the only thing that will "SAVE" one. :B

I may try cycle the 12 ah batteries a time or two just for the heck of it.