Introduction: Repair Sealed Lead Acid Batteries

Picture of Repair Sealed Lead Acid Batteries

Has your battery lost some of it's capacity?

It turns out that Sealed Lead Acid (SLA) batteries are not infact all that well sealed. You can perform maintenance on them much the same as you would any other wet cell battery, such as car batteries.

In this instructable I will show you how to do this.

Step 1: This Is How We Do It

What you will need:

-Distilled water

-Small straight screwdriver

-superglue or hot glue

-a syringe or pipette

Safety Considerations:

Wear safety goggles and gloves as the fluid in the battery is generally sulfuric acid

How to go about it:

1/ Remove the cover on the top of the battery using a small straight screwdriver.

2/ You will find little rubber or plastic caps on the individual cells of the battery, remove these.

3/ Using your pipette or syringe, fill the cells of the battery until the lead plates inside the battery are submerged, you will be able to see through the hole.

4/ In a ventilated location, connect a charger for an hour with the caps off. If you have over filled any of the cells any excess acid will bubble out. With your gloves use a bit of paper towel to soak this up and dispose of it in a safe manner.

5/ Replace the caps and then using your adhesive, stick the cover back over the caps.

6/ Give it a good charge and it should have a better current capacity again!


sudhir8014 (author)2016-11-26

Hi...I tried this method with 12v sealed battery and charged it for 12hr with connection source +'ve to battery +'ve and source -ve to battery -ve but it's not charging more than 1V...ways a problem...

demola made it! (author)2016-10-10

pls how do i open this battery it was swollen the next the after charging it an elite 200amps battery

tom_sanremo (author)demola2016-10-10

Be REALLY careful. I'd say it has overheated or the stuff inside has boiled and it hasnt vented. You might get acid everywhere. If it is a gel battery it wont be save able. This only works on the batteries that are a sealed wet cell. I've had this happen to a smaller one from a backup supply and it was just a case of it being too far gone to save.

demola made it! (author)2016-10-10

it realy good but how do yo open mecury elite 200 it was swollen by the side after charging

acheide (author)2016-03-21

This is good to know. Thanks.

About This Instructable




Bio: I need more space for my projects, my garage is packed. I like to make things, I've always got a project on the go.
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