Battery Desulfator for Battery Reconditioning or Maintenance

Published by: Nick Meissner

Battery Desulfator

There are so many gimmicks and gadgets out there that I pretty much tune them out. And when they make big claims, it’s especially obvious!

When it comes to extending the life of batteries, there is no exception to this rule. Lots and lots of gadgets out there! Some good, and some a waste of money (or worse).

In this post, you'll see one of the very few “gadgets” I use with my off-grid solar batteries.  It’s called the Battery Life Saver, but generically most folks refer to these devices as a battery desulfator.

What Is a Battery Desulfator?

This section is a little bit technical, so skip to the next section if you get bogged down.

Here’s the short version…When charging or discharging lead acid batteries, a chemical reaction is happening. While using power from your battery (discharging), lead from the plates inside your battery is being converted into lead sulfate. And when your battery is being recharged, that lead sulfate is converted back into lead.

Sulfation on lead plates
Sulfation on lead plates

That is how it’s supposed to work. But unfortunately, this reaction doesn’t always happen properly (especially if you are not treating your batteries nicely). Sometimes, bits of lead sulfate may form into lead sulfate crystals. These crystals cannot transform back into ordinary lead and they collect on the surface of the plates (kind of like corrosion).  When this happens, the crystals combine with any impurities in the acid—which is why you only want to use distilled water in batteries.

This sulfation happens gradually, but with enough time these lead sulfate crystals can interfere with the chemical reaction and negatively affect your battery’s capacity and lifespan.

So what’s the solution? First, if you properly maintain your batteries, they will be less likely to suffer from sulfation.  One key tactic is to fully charge your battery at least once every 7-10 days. Also, periodic equalizing (overcharging) can help also, but equalizing is not the answer for reversing sulfation.

While equalizing your battery will stir the acid (which is good), it cannot dissolve much if any of the lead sulfate crystals. And that is where the Battery Life Saver comes in.

From what I understand, many of the cheap “desulfators” use small pulses of power that knock the lead sulfate crystals off the lead plates. That may seem good, but it really isn’t. First, the lead sulfate crystals are still unusable by the battery even once they are knocked off the plates. So your battery capacity and lifespan is decreasing even with the “desulfator”. Second, once enough lead sulfate crystals collect in the bottom of your battery, it can eventually (after years) pile up to the point of touching the lead plates and shorting them out.

But the Battery Life Saver is different. It acts as a microscopic radio transmitter that sends out a frequency that resonates with the lead sulfate crystals and dissolves them. Remember the old radio crystal receivers? The crystal would resonate with the frequencies that the radio station was transmitting on. But now, instead of playing audio from a radio station, the crystal is dissolved so the battery can use that material again.

Battery Desulfator In Action

That's the theory.  In reality, we bought a home with an old bank of Trojan L-16 batteries in it. I expected them to bite the dust right away, but they kept going and kept going. We managed to squeak 10 years out of them, which is impressive—especially considering the circumstances they were used under. What do I attribute that to? The main factor I attribute this longevity to is the Battery Life Saver that kept the battery plates cleaned up continuously.

Another friend shared with me about an old bank of badly sulfated deep cycle batteries that he inherited. They were to the point of being unusable, but he hooked up a Battery Life Saver to do some battery reconditioning and within weeks saw an improvement.  Within a few months, he experienced a fairly dramatic restoration to usable condition.

And I have heard of so many similar stories.  So much so that I'm convinced.

Am I saying the Battery Life Saver is capable of working miracles?  That it will resurrect your dead batteries? Certainly not!

Is it a great preventative maintenance tool? Absolutely!

And is it worth trying on a sulfated bank of batteries? I definitely think so. You have nothing to lose at that point!

Battery Desulfator Brands

Please be aware that not all desulfators are created equal!

If you do much searching online, you’ll find reviews from dissatisfied customers complaining about their worthless desulfator. I’ve found that 9 times out of 10, they are referring to one of the many cheapo “desulfators”.

So I stick with the tried and true desulfators that we have used for many years and many other off-grid folks use as well. And that’s the Battery Life Saver.

I know this may sound like a paid commercial, but it’s not! I have no connection to the company and could just as easily refer you to one of the many cheaper options out there on Amazon or elsewhere. But I’m referring you to the desulfator that I personally use and have used for many years.

The BLS-12/24C is what you want for a 12 or 24 volt battery bank that is 1,000 amp hours or less. The BLS-24/36 Multi-F is ideal for 24 volt battery banks that are larger than 1,000 amp hours.

The BLS-48A is the way to go for 48 volt battery banks smaller than 1,000 amp hours. And the BLS-36/48 Multi-F is what you want if your 48 volt battery bank is larger than 1,000 amp hours.  (a couple of those links will help support our site without costing you a penny extra)

I prefer the ring terminal options (as opposed to alligator clips), but in the case of the Multi-F models, only alligator clips are available stock. However, if you order from the company’s site, on the order form you can put a request in the comments section for ring terminals to be used. At least as of this time, the owner will do that for you at no extra charge.

One Word Of Caution

My personal experience is that a quality desulfator (like Battery Life Saver) is not only harmless to a flooded lead-acid battery but is absolutely helpful.

But I want you to be aware that some battery manufacturers see it otherwise. For instance, Trojan states “We don’t recommend the use of desulfators or any other external device, as they tend to do more harm than good.”

I totally do not understand this, but it may be that some of the other desulfators out there have caused issues. I don’t know. Some people will say that they don’t like desulfators because they want you to have to buy new batteries more frequently. I can’t comment on theories like that, but just be aware that using a desulfator could potentially void the warranty on your batteries.

Because of the warranty issue, I often advise folks that they might want to avoid using a desulfator on Trojan (or other anti-desulfator company) batteries until after the warranty period has expired. As I see it, that is a real shame, as desulfators are best used for preventative maintenance rather than fixing a problem. But that is a call you will have to make.

On the bright side, some battery manufacturers actually encourage the use of desulfators. For instance, the owner of GB Industrial Batteries (my favorite forklift battery maker) personally recommended the use of a desulfator on any brand new batteries purchased from him.  Not only that but he said they are great for preventing sulfation and should be used from the beginning of the battery’s life.

Any questions or comments about battery desulfators?
Let me know in the comments below


  1. Boo Radley

    What about AGM batteries?

  2. david king

    i'm puzzled. Aren't all batterys totally sealed up these days? how then can u get desulfaters inside the battery?

    • Nick Meissner

      Hi David, Take a peek at the video that is embedded in this blog post. I think that will clear it up for you. The desulfator has 2 wires (positive and negative) and they attach to the positive and negative terminals on the battery bank. So they can physically attach to any battery. But they are only for use with lead acid batteries.

      Hope that helps. Take care,

      • david+king

        ok, got that part now. How do i find out which batteries are lead acid? Are car batteries? How much does the desulfator cost?

      • Nick Meissner

        Most regular car batteries are lead acid, including flooded lead acid (the older kind with liquid acid solution), sealed gel cel, and sealed AGM (absorbed glass mat). You can pick up cheap desulfators for probably $20+ online or an auto parts store. But the Battery Life Saver that I recommend is a really sturdy unit that goes for $100+. It's really a good idea for a large off grid battery system where you have a significant investment in batteries. It may not make financial sense if you are only going to be using it for a car battery that costs less than the desulfator.

  3. Jeff

    I believe you when you say that the Battery Life Saver is a worthwhile investment but I also believe a little history of crystal radios is in order here if you please. A crystal radio consists of 5 main parts. 1) an antenna, 2) a capacitor, 3) a coil, 4) a rectifying device, (A crystal, traditionally galena which is lead ore later replaced by a solid state germanium diode.), 5) a high impedance, usually a 2K ohm, crystal type earphone. It is the coil and capacitor connected in parallel that is the resonating device. After the radio signal is received by the antenna, which is connected to the top of the coil / cap set, and is resonated by said coil and capacitor. At this point in the signal chain, it is still burdened by the carrier wave which would be heard as a hum. The galena crystal, connected in series to one side of the cap and coil and the other end to one side of the earphone, would be scratched with a "cat's whisker" wire until a sweet spot was found that would rectify and filter out the carrier wave leaving the voice / music modulated signal to be delivered to the earphone. The cat's whisker being the other end of the galena crystal circuit. The other end of the earphone is connected to the remaining bottom end of the coil / cap combination which is usually grounded to a copper water pipe. When solid state germanium diodes were invented, they replaced the galena crystal because they didn't have to be played with to find the sweet spot. In the old tube type radios, they used a rectifier tube instead of a crystal. Where I think you got confused is the tuning crystal in a CB or police radio or scanner, for example, is electronically equivalent to the coil / capacitor combination but is many fold more accurate and much less susceptible to heat and vibration disruptions not to mention much smaller than caps and coils. During WW II, military men in the field used to use the old Gillette blue razor blades in place of the galena crystal and sometimes even their blued gun barrels in this circuit to listen to the BBC for news of the war. Some even used pencil "lead" graphite scribbled on paper, all because of their crystalline structures ability to crudely rectify a radio signal their and ready availability in the field. Jeff M.

  4. Mike

    Well nick think about it --if your business model is selling batteries the last thing you want is for customers to keep renewing their batteries with this technology I mean DUH . Kinda like curing a disease and losing a future sick customer with all the drugs and office visits and eternal visits to the hospital and how is that going to work on your business model AKA you need sick people or batteries same thing.

  5. James Goodman

    Can you recommend a desulfator for solor batteries available in the Philippines?


Submit a Comment

Your email address will not be published. Required fields are marked *

Subscribe to our Newsletter