Bubbling batteries. (1 Viewer)

[simsy56]

I have just fitted a 130w solar panel to my RV, along with an MPPT controller. The 2 x leisure batteries are 'bubbling' as they would if on a trickle charge on the bench. Is this correct?

Craig

 

[DBK]

What's the voltage? What type of batteries have you got?

 

[simsy56]

2 x 12v Trojan lead acid batteries in parallel.

Craig

^{_{Subscribers  do not see these advertisements}}

 

[PhilandMena]

As DBK states above. Check the voltage going into the batteries at the battery terminal with a digital volt meter. Also, check your controller is set for the right type of battery e.g. Lead Acid, AGM or GEl. I'm guessing it's Lead Acid and if so expect between 14.4 V and 13.6 V depending on state of batteries. You might want to check again after a good charge and top up if required. Some batteries are thirsty, Banner being one.

 

[simsy56]

When first connected, 14.5v was the reading, in bright sunlight, the second day, still in bright sunlight the reading was 13.2v. The controller is correctly set up for flooded 12v.

Craig

 

[PhilandMena]

Your good to go !

^{_{Subscribers  do not see these advertisements}}

 

[simsy56]

So, is the 'bubbling' normal?

Craig

 

[PhilandMena]

So, is the 'bubbling' normal?

Craig

It is normal for a flooded lead-acid battery to make a bubbling sound during the charging process and water can be added to replace evaporated fluid. Sealed lead-acid should never be made to bubble since any vented gases cannot be replaced and air pockets form in the battery which ruin its conductivity and lifespan.

With a flooded lead-acid battery the sound will usually become barely audible as battery reads 13.8 on the voltmeter (minimum voltage for charging). As the volts on the voltmeter increase, the bubbling sound will increase in intensity.

In the normal charging range, this bubbling is caused when an electric current from your charger is passing between the positive and negative plates in the battery’s cells and through the electrolyte solution. This results in electrolysis which excites the electrolyte solution and releases hydrogen and oxygen gas from the “water”.

Now, sealed batteries, such as gel or AGM, certainly have the ability to make noise when charging. However, a bubbling or hissing sound is an indication that too much charge is being applied and irreversible damage is occurring. The charging process must be stopped and corrective action needs to be taken to resume charging.

Never allow a sealed lead-acid battery to bubble or hiss when charging!

 

[Armytwowheels]

So, is the 'bubbling' normal?

Craig

Colin says no. Bubbling usually means too fast a charge. Are they actually bubbling or fizzing. Bubbling means hydrogen gas is coming out of the batteries.

^{_{Subscribers  do not see these advertisements}}

 

[simsy56]

Just 'bubbling' as they would on a bench charge. I am just going to check them today, and will report my findings.

Craig

 

[PhilandMena]

Fairly certain your OK ! You have already confirmed the state of charge at 13.2 V down from 14.5 V and this is normal. What your hearing is the electrolysis reaction taking place as stated above. More fizzing than bubbling , which will soon stop.

 

[simsy56]

Just checked the batteries, and the voltage is 13.8, bubbling seems much quieter now, batteries indicated as full. I will keep a close eye on them. Thanks for your replies.

Craig

^{_{Subscribers  do not see these advertisements}}

 

[Flatlander]

Colin says no. Bubbling usually means too fast a charge. Are they actually bubbling or fizzing. Bubbling means hydrogen gas is coming out of the batteries.

Colin (Who's Colin? Any relation to Alice in the song? ) is correct. The charge rate, in terms of amps, is to high.

 

[PhilandMena]

Colin (Who's Colin? Any relation to Alice in the song? ) is correct. The charge rate, in terms of amps, is to high.

Unlikely as charge is coming from solar panel and has dropped from full charge to a float charge.

 

[Flatlander]

Unlikely as charge is coming from solar panel and has dropped from full charge to a float charge.

Even a float charge can be to high in some circumstances.

^{_{Subscribers  do not see these advertisements}}

 

[autorouter]

Electrolysis (splitting off hydrogen and oxygen gases) is mostly due to the antimony in the plates. The plates in a lead-acid battery are not made from 100% pure lead, because it is not mechanically strong enough. In classic old-style lead-acid batteries the plates are a lead-antimony alloy, which is stronger.

They can now be made of lead-calcium alloy, sometimes with silver added too. These batteries hardly gas at all, unless they are overcharged. They require very little water topping up in normal use, and are described as 'low-maintenance'.

If your batteries are gassing, check the voltage (13.6 to 13.8 volts or lower), and check the current 200 milliamps (0.2 amps) maximum. For classic lead-acid batteries, a small amount of gassing is normal. Otherwise, maybe your charger or a battery is at fault.

If for example a cell has shorted, then the 13.6 volts is applied to the remaining 5 cells, which will overcharge them and cause gassing.

 

[PhilandMena]

Even a float charge can be to high in some circumstances.

Perhaps! but how do you know this is actually happening in this case ??? I believe your just guessing without any hard facts!

 

[PhilandMena]

Electrolysis (splitting off hydrogen and oxygen gases) is mostly due to the antimony in the plates. The plates in a lead-acid battery are not made from 100% pure lead, because it is not mechanically strong enough. In classic old-style lead-acid batteries the plates are a lead-antimony alloy, which is stronger.

They can now be made of lead-calcium alloy, sometimes with silver added too. These batteries hardly gas at all, unless they are overcharged. They require very little water topping up in normal use, and are described as 'low-maintenance'.

If your batteries are gassing, check the voltage (13.6 to 13.8 volts or lower), and check the current 200 milliamps (0.2 amps) maximum. For classic lead-acid batteries, a small amount of gassing is normal. Otherwise, maybe your charger or a battery is at fault.

If for example a cell has shorted, then the 13.6 volts is applied to the remaining 5 cells, which will overcharge them and cause gassing.

Again! Do you actually know for sure the type of lead acid battery the O.P. has and if there is a fault with one of the cells. I.M.O. the most obvious cause is electrolysis which is normal in Lead Acid batteries and as stated by the O.P. this has reduced now the batteries have reached the float stage. Perhaps the term bubbling is misleading members and they are in fact fizzing which is normal.

^{_{Subscribers  do not see these advertisements}}

 

[simsy56]

I have been and checked again, 13.2v and 0.2a showing on the readout. Only the tiniest bit of 'bubbling'/'fizzing' is happening now.

Thanks for your input guys.

Craig

 

[autorouter]

Do you actually know for sure the type of lead acid battery the O.P. has

No.

the most obvious cause is electrolysis which is normal in Lead Acid batteries

Yes that's the most obvious cause. But gassing is also caused by faults. The charger could be stuck in high voltage mode, and not switching to trickle charge mode. The MPPT controller could be set up for 24 volts not 12 volts. One of the cells of the battery could be shorted.

That's why I suggested checking that the voltage was about 13.6 volts and the current about 0.2amps. If so, and if it's a classic lead-acid battery with lead-antimony plates, then it's just normal gassing.

I have been and checked again, 13.2v and 0.2a showing on the readout. Only the tiniest bit of 'bubbling'/'fizzing' is happening now.

Sounds like normal gassing to me (but that's only a guess of course).

 

[Flatlander]

Perhaps! but how do you know this is actually happening in this case ??? I believe your just guessing without any hard facts!

Not guessing, just using my own experience based on the same available facts as everyone else, including yourself. Therefore, if I dont have enough "hard facts" neither do you!

^{_{Subscribers  do not see these advertisements}}

 

[PhilandMena]

Not guessing, just using my own experience based on the same available facts as everyone else, including yourself. Therefore, if I dont have enough "hard facts" neither do you!

Fair enough. However, the O.P. did say in his opening statement that they were bubbling just like a battery when on a tricklle charge. Which I thought was an important fact!