AGM battery squeaking while charging?

[Red Squirrel]

I tend to only deal with flooded batteries as I like that I can just add water and if cared for well they last long. Gel/AGM you can't. Gels don't tend to last long at all and not sure about AGM as it's my first time having one.

It's a 79ah 12v battery for a portable solar setup that will be on wheels and need to be able to tilt and go on various terrain so did not want to use flooded.

I am not in a position to build this system yet but wanted to test the inverter and have it hooked up. I had a 7 amp charger on it set to AGM mode and noticed it was bringing the voltage to 14v which seems high for an AGM. Noticed a small squeaking sound coming from the battery. Does it mean it's venting? This is bad for an AGM right? Or is it normal for a new one, and will that stabilize after a while?

I'm hoping that once my charge controller arrives it has a setting to set a max voltage then this won't be an issue. I can set it to like 13.5. But just wondering if I'm worrying for nothing about the noise.

At some point I do want to play with Lithium batteries but I'm not quite there yet as far as electronics knowledge goes. I have a rough idea for how to do the balance charging but I have not breadboarded anything yet.

 

[sunshine_eggo]

I tend to only deal with flooded batteries as I like that I can just add water and if cared for well they last long. Gel/AGM you can't. Gels don't tend to last long at all

Usually because of improper charging. When treated within their ratings, they tend to outlast AGM.

and not sure about AGM as it's my first time having one.

AGM tend to last 1/2 as long as well maintained flooded lead acid and about 3-4X as long as poorly maintained flooded lead-acid.

It's a 79ah 12v battery for a portable solar setup that will be on wheels and need to be able to tilt and go on various terrain so did not want to use flooded.

I am not in a position to build this system yet but wanted to test the inverter and have it hooked up. I had a 7 amp charger on it set to AGM mode and noticed it was bringing the voltage to 14v which seems high for an AGM.

Not at all, but it depends on the AGM. Many AGM charge in the 14.4-14.8V range.

Noticed a small squeaking sound coming from the battery. Does it mean it's venting? This is bad for an AGM right? Or is it normal for a new one, and will that stabilize after a while?

AGM are VRLA batteries - Valve Regulated Lead Acid. The squeaking might be a sign that one of the valves is not holding pressure, or that one of the cells is exceeding allowed pressure and forcing the valve to open.

I'm hoping that once my charge controller arrives it has a setting to set a max voltage then this won't be an issue. I can set it to like 13.5. But just wondering if I'm worrying for nothing about the noise.

At 13.5V, the battery may never get fully charged. AGM/GEL typically need 13.6-13.8V in "standby" mode to achieve full charge after a very long absorption period - something approaching 24 hours.

At some point I do want to play with Lithium batteries but I'm not quite there yet as far as electronics knowledge goes. I have a rough idea for how to do the balance charging but I have not breadboarded anything yet.

No breadboarding is necessary even for DIY. There are several inexpensive 12V LFP batteries that Will has tested that require no breadboarding or special knowledge - simply the ability to read and follow a few sentences of directions.

 

[Red Squirrel]

So does this mean the battery might be defective then? 7a is also not a lot of charge at all so I fear this will only be worse once it's on solar and in a heated environment.

 

[sunshine_eggo]

That would be my concern.

 

[Red Squirrel]

Going to cycle it a few times while it's within warranty period and see how it goes...

I put clear plastic tape over the cell caps, if there is any leakage it should cause a bulge in the tape or something visible at least. Also been measuring temp of cells to see if any are warmer than others but don't see anything that stands out.

I'm hoping that maybe this is normal as maybe they are slightly under pressure at factory and it just needs to relief a bit of pressure?