MattA wrote: ↑Mon Apr 25, 2022 6:25 am
I desulfated the batteries by themselves at first and then to speed things up I desulfated the two 0AH and the two 3AH batteries in series (0AH and 3AH were desulfated at different times). All four batteries have been connected in parallel and desulfating since Saturday morning. I don't think this is the correct way to do this and will recharge the batteries and switch back to one battery at a time.
So I went and read a lot more reviews for your device. Many of the people that claimed success described very long times, even a month, and going in cycles of separately desulfating and charging, as the desulfator discharges the battery. Some also say that the battery has to be charged to about 11V or so, for the desulfator to work. I wonder if we could put the charger and desulfator on the battery at the same time, with diodes in series with the positive lead for each desulfator and charger.
What you did with the batteries in parallel isn't necessarily wrong, but if it doesn't work you have one extra thing to doubt. Anyway, you got me excited about this little desulfator
The desulfator has a low voltage cutoff around 11.5V. AFAIK there are battery chargers with built in desulfator. I think these start in the $50-100 range.
I think you could hook the desulfator up to the battery directly and put a diode in series with your battery charger. Make sure the battery is already charged to limit the power dissipation on the diode. Also make sure the diode has sufficient voltage rating. I recall reading these desulfators can generate spikes of at least 100V. If your buying a diode, get a diode with a fast reverse recovery time. Feel free to ask for help
MattA wrote: ↑Mon Apr 25, 2022 8:14 pm
The desulfator has a low voltage cutoff around 11.5V. AFAIK there are battery chargers with built in desulfator. I think these start in the $50-100 range.
I think you could hook the desulfator up to the battery directly and put a diode in series with your battery charger. Make sure the battery is already charged to limit the power dissipation on the diode. Also make sure the diode has sufficient voltage rating. I recall reading these desulfators can generate spikes of at least 100V. If your buying a diode, get a diode with a fast reverse recovery time. Feel free to ask for help
Matt, did you hook it up to an oscilloscope? I'd be surprised that the switching/pulse frequency is that high to need a fast recovery diode. I have lots of diodes, I'll find something that should be good enough like 3x the max amperage or so, and maybe double the max voltage. I ordered the same unit you have from amazon.ca and will hook it up to an oscilloscope when I get a chance. I'll reach out if I don't understand something, it'll be interesting.
If the desulfator has a low voltage cutoff I'm thinking we can trick it into spiking a low voltage battery by putting a good battery in parallel with the low voltage one that would have a couple or more diodes in series with it. Then the desulfator sees a higher voltage and spikes both the good and the lower voltage battery.
Now I'm wondering if the desulfator has a high voltage cutoff too, because if I put a charger to the battery I want to spike it may present to the desulfator a voltage high enough that it won't pulse.
Eugen - I don't have an oscilloscope here at home. I'd have to borrow one from work or bring the desulfator to work. I've got some 100X high voltage probes at work.
The box/paperwork lists the cutoff voltages as 11V for 12V battery, 22V for 24V battery, 33V for 36V battery & 44V for 48V battery.
The listed pulse frequency is 10KHZ
Peak voltage is 60-100V
Peak amp is 2amp max
Working amp is 20mA
Cutoff amp <5mA (not sure what this spec is)
@MattA look at this. I thought this battery was not so good. It charged up to 12.4V. Hooked up the desulfamacator and this is what it shows on the scope during pulsing. The spike is about 1.4V.
Well, this device is a funny one. Here are a few observations/thoughts I have about it.
The desulfator has no battery of its own, and no cable to hook it up to a power source. The power source of this device is the battery that it's supposed to desulfate. That's probably why it only comes on if the battery is 11.5V or higher. I also noticed that when the battery was 13.1V the device did not start beeping/pulsing.
The manual states that the pulse frequency is 10kHz. What I see on the scope is a spike approximately every 16 microseconds. That would give us a frequency of about 62.5kHz. Also in the manual: Peak Voltage = 60-100V. Well, what I see is a spike that's around 1.5V. Perhaps the higher voltage spike happens when the battery is in worse shape, therefore lower voltage? The battery I tested it with was 12.4V and maybe it's not sulfated enough?
In any case, the proof is in the pudding. I'll try to find a battery in worse shape and try it again.
You may wonder if the scope might be malfunctioning, or out of calibration. This could be the case, but very unlikely, I rarely used it in the last few years and it was fine last I used it.
Eugen wrote: ↑Fri Apr 29, 2022 9:33 am
Well, this device is a funny one. Here are a few observations/thoughts I have about it.
The desulfator has no battery of its own, and no cable to hook it up to a power source. The power source of this device is the battery that it's supposed to desulfate. That's probably why it only comes on if the battery is 11.5V or higher. I also noticed that when the battery was 13.1V the device did not start beeping/pulsing.
The manual states that the pulse frequency is 10kHz. What I see on the scope is a spike approximately every 16 microseconds. That would give us a frequency of about 62.5kHz. Also in the manual: Peak Voltage = 60-100V. Well, what I see is a spike that's around 1.5V. Perhaps the higher voltage spike happens when the battery is in worse shape, therefore lower voltage? The battery I tested it with was 12.4V and maybe it's not sulfated enough?
In any case, the proof is in the pudding. I'll try to find a battery in worse shape and try it again.
You may wonder if the scope might be malfunctioning, or out of calibration. This could be the case, but very unlikely, I rarely used it in the last few years and it was fine last I used it.
I have a large battery for the winch in the bigg trailer that I would like you can try it on .
That'd be great @DavidBarkey! The only wrinkle is that I can't come by today, tomorrow I'm gone to Toronto for a haul, so I don't know when I'll be able to come by.
Eugen wrote: ↑Fri Apr 29, 2022 10:18 am
That'd be great @DavidBarkey! The only wrinkle is that I can't come by today, tomorrow I'm gone to Toronto for a haul, so I don't know when I'll be able to come by.
When ever you can . I sure you will need eggs soon anyways .
