*Testing and Cleaning your Batteries*
By: Eli
12 April 2003

This goes along with Warlordís Adding Water to Your Storage Batteries article only Iím concentrating more on the testing & cleaning portion. I suggest that you read that article also.

The other night I was having one of my sleepless nights so at about 0030 I started cleaning the battery bank.

Items you will need:

The baking soda/water mix is for neutralizing and removing acid from the batteries and your hands.

Squirt bottleÖDUH!

Find a squirt bottle and dump some baking soda into it. I didnít measure it, but Iíll guess that I have about 3-5 tablespoons in this bottle. Then fill it up with water and shake it up. Just like a Vodka Martini "Shaken, not stirred." Actually it doesnít matter as long as it gets mixed, but I wanted to see how many of you 007 fans caught onto it.

Now itís time to test and clean the bank.

I let my batteries go through a charge cycle and then float. I have mine set to float at 13.0 volts and bulk at 13.8 volts. After they floated for about an hour I started. The reasoning is if I had hydro tested them during a charge or immediately after charging they would have excellent readings. By letting them sit and drop to a float voltage I would get a more accurate reading.

The first order of business is wear crappy clothes that you donít care about. I promise you that YOU WILL get battery acid on them regardless of how careful you are. Also ALWAYS wear safety goggles!!!!

The second order of business was testing. It wouldnít make much sense to clean the batteries and then dribble acid on them again, kinda defeats the purpose.

The gizmo you see above is called a Hydrometer. It measures the specific gravity of each cell. To put it all into English it tells you the condition of the cell and the charge state of the battery.

Notice the Red; White & Green float inside the glass. The glass rod float must not touch the bottom rubber piece or the top rubber piece. If it does you will get a false reading. It needs to float freely in-between. The float is numbered from 1100-1300.

The Red, White & Green means in order- bad, needs service, good.

Once your goggles are on pry open the vent caps with a short flat bladed screwdriver. Use a short one to eliminate any chance of shorting out the + & - terminals.

Visually check the water levels, if they are good commence testing.

Squeeze the bulb on the top of the hydrometer and then stick the tip of it into a battery cell. Slowly release the bulb. This will cause suction and fill the glass tube. Once the bulb is completely released, slightly squeeze and release it a couple times (for the lack of better terms I call it "chugging"). This will cause the inner glass rod to bounce up and down. The reason for this is to release any air pockets there might be. An air pocket WILL cause you to get a false reading.

Hereís the pic again

After you have drawn the water/acid mix into the hydrometer and "chugged" it a couple of times, this is what you want to see. Re-emphasizing--- The glass rod is free floating and not touching the top rubber piece or the bottom rubber piece. Ideally it will float in the Green range. If it is in the White range itís prolly because the battery hasnít been charged for a while. If itís in the dreaded Red range the battery needs charging. With my charge controller the batteries are always charged so Iím always in the Green.

If you dribble any acid on the tops of the batteries wipe it up with the rags or paper towels.

Once the batteries have all been tested itís time to clean them.

I used my squirt bottle and cleaned each vent cap. Squirt a little on it then wipe it off. This neutralizes any acid that may have bubbled out of a cell during charging. When the baking soda/water mix comes into contact with acid it will fizzle and foam like Hydrogen Peroxide, this is good then just wipe it off.

Dirty batteries on the left, clean battery on the right


Little bit of acid around the edge Cleaned up nice and purddy

A little acid may crust around the cells this is no big deal. Use the baking soda/water mix to clean it off. DO NOT get the mix into the cells or you just killed your battery. Squirt the mix onto a paper towel and then wipe around the cells. After the cells and vent caps are clean reinstall them.

I then used my squirt bottle and cleaned the batteries. Keep in mind that water conducts electricity, so I didnít just doosh down the batteries. I did half at a time. Squirt the terminals and everything on one side, wipe it all down and do the other side.

Once everything was cleaned up, I reinstalled the interconnect wires and put the bank back on-line.

I doused my hands with baking soda and then washed them off.

Thatís about all there is to it.

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