Stratification: The Hidden Battery Killer

And what you can do about it

By Emanuel Hillmann

The final objective of any battery is to store and provide energy when needed.  Lead acid batteries are ideal for golf carts, NEVs, forklifts, RVs, boats and many other battery applications. As we have covered in other articles, a fully charged, new battery is basically a cell or group of cells made of a plate of lead, a solution of sulfuric acid and another plate of lead oxide. A byproduct of discharging is lead sulfate. When you recharge batteries, the lead sulfate reverses to the original elements; lead, lead oxide and a sulfuric acid solution.  In most cases and over time, the process is not fully reversed. The lead sulfate crystallizes and does not go away by normal recharging, eventually making the battery nonoperational.

If nothing else is wrong we can reverse that process. We can recover batteries. The Battery Life Saver™ electronic device generates a range of frequencies that match the frequency of the different sulfate crystals, dissolving them and enabling the natural recharging chemical process that reverses battery deterioration.

The process must be gradual to protect the integrity of the plates in the batteries and prevent the dropping of crystals to the bottom. Any crystals that get dropped are basically lost. They not only weaken the battery, but with enough accumulation, can cause an electric short in one or more cells.

This situation brings up a problem: How can we speed up recovery and improve maintenance without destroying the plates?
To solve this question we need first to keep in mind basic maintenance. Water regularly (only distilled water), clean the terminals connecting the batteries and the charger and protect the batteries as much as possible from extreme weather… Hot weather will speed up deterioration; very cold weather can freeze the electrolyte, destroying the battery as well.

Secondly, we need to better understand what happens inside a battery.  I found that many people have been ill advised about the recharging process. Many are told to only recharge when the system has been used for long periods of time, not to recharge after light use. This could not be further from the truth. The longer a battery has been left in a lower state of charge, the more crystals it accumulates. Below 80% State of Charge (SOC) batteries start accumulating crystals exponentially and those crystals tend to remain. Plus the light use not followed by immediate recharge often causes a phenomenon that we have not talked much about: battery stratification.

Stratification simply happens over time.  The sulfuric acid solution tends to concentrate in the bottom of the battery creating some lethal problems. The heavily concentrated sulfuric acid will corrode the plates in the lower section. It will read as a high voltage when the battery has not been fully recharged, therefore the charger will stop the charging process prematurely. In the meantime, you have accumulated more and more crystals, many of which will not go away or will simply drop to the bottom of the battery, resulting in shortened battery life.  Stratification gets worse after long periods of disuse, such as occurs in the storage.

What to do?

Some people shake their batteries on a regular basis to mix up the solution.  This is impractical and dangerous as you can spill the acid. I have seen some recovery when using a hydrometer to pump the solution many times in each cell as it is done to read the battery condition. But again you should be careful and take all necessary precautions and wear protection when working with acids.

There are many simple things you can do to reverse this problem, at the same time speeding up your battery recovery and maintenance:

Recharge your system every time you use it, even if it has only been used for a few minutes.

After you finish charging your batteries, disconnect your charger and let the batteries rest during the night. The rest period will allow the charge to be more evenly distributed in the solution. In the morning, before using the system, start the charging cycle again.

Following this simple routine, which we call the “Double Charge”, will eliminate stratification from the get go, even if you have new batteries. This procedure is not the same as equalization, as you have let the batteries rest between charges.  In equalization, you disconnect and reconnect the charger immediately after finishing the charging process. I do not recommend the typical equalization process as it tends to deteriorate the plates.
In the case of golf cart, RV and boat owners, if you only use your system on the weekends, do a recharge in middle of the week and another in the morning before using your system.

During the storage season recharge your system regularly. After the winter is over, and before you start using it, recharge your batteries with a low amp charger. A long charging session of 16 to 24 hrs at 2 amps will greatly help to eliminate the stratification. If you are unable to charge regularly during storage, we recommend fully charging them, and then disconnecting them from each other before letting them sit. It is ideal to keep them stored in a controlled climate.

The extra recharge sessions while using the BLS will eliminate the stratification and speed up battery recovery and maintenance.

In summary:

1)    Do the regular maintenance: distilled water, terminal cleaning, protection from weather elements and recharge as soon as you have used your system.

2)    Charge your batteries and let them rest 8 to 24 hrs and recharge again, even if you have not used them.

3)    During storage recharge your batteries regularly. If you are unable to charge them regularly, charge them fully then disconnect them from each other and try to store them in a controlled climate.

4)    After storage and before using the batteries recharge them in low amperage setting between 16 and 24 hrs. Let the system rest and then recharge as usual before starting regular use.

This article will be helpful to speed up battery recovery and maintenance of your battery system.  Please let us know if you have any questions or suggestions.


"I am an RV owner. I want to tell you that the Battery Life Saver brought back my $225 battery that was in very bad shape. It took a while but it’s still working great. It makes me very happy."

T.B. Bend

BLS Customer