Making a desulfator modifying an AC adapter for a laptop
This desulfator makes pulses shown below and this sure can revive
sulfated batteries.
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X: 5μsec/div. Cycle is about 50μsec with some jitter
Run in part. negative peak -4.5A. X: 100nsec/div
Current peak 6.6A X: 200nsec/div
Modified AC adapter for a laptop
I happened have informed about a desulfator which de-sulfate
a car battery by a friend of mine. His purpose was to use aged
batteries that weren't good enough to use for automobiles any
more due to the increased internal ESR caused by the sulfation.
He has a home made solar system designed to work at 24V and
he uses 2 car batteries in series. His desulfator is almost the
same with this one explained here below.
http://fucimin.altervista.org/desulf/desulfator.pdf
The power source of above is the battery itself and a battery
charger is needed separately when to use because the battery
is discharged while desulfating and becomes empty as the
desulfation goes on.
I happened to find a patent below when searching the Net
and it explains about the actual frequencies and the current.
Patent: Pulse generation device for charging a valve-
regulated lead-acid battery
https://patents.google.com/patent/WO2004070909A1/en
The important figures are claimed as below.
4. A pulse generation device as claimed in claim 2,
wherein said first frequency is in the range of 50 kHz
to150 kHz and said second frequency is in the range
of 10 Hz to 500 Hz.
5. A pulse generation device as claimed in claim 1,
wherein said pulses are square wave pulses.
6. A pulse generation device as claimed in claim 2,
wherein the first frequency pulses have an on time
in the range of 1 to 10 μs and an average current
in the range of 20mA to 60 mA.
When I was reading the contents, I got an idea to make a unique
desulfator which can charge and desulfate the battery at the
same time. My idea is to modify an AC adapter for a laptop PC.
Many of those AC adapter has a out put of DC 19-20V range
with a PFC circuit to meet the regulation of the power factor.
Most of those stop the PFC function when the load is small
and the deactivation is useful to get the second frequency
explained at the number 4.
Below is the result of 4 days after the desulfation was started.
I also took a photo just when started but I can't find it now.
I remember almost all the part was white then.
Day 4.
Day 14.
You can see how the sulfation was decreased. Actually the
battery became quite OK to start the engine easily.
Before the desulfation was done, no matter how I charges the
battery using a regular charger,it was impossible to start the
engine.
sulfated batteries.
Currentwaveform to a battery 40B. Y=2A/div, X=1us/div
I happened have informed about a desulfator which de-sulfate
a car battery by a friend of mine. His purpose was to use aged
batteries that weren't good enough to use for automobiles any
more due to the increased internal ESR caused by the sulfation.
He has a home made solar system designed to work at 24V and
he uses 2 car batteries in series. His desulfator is almost the
same with this one explained here below.
http://fucimin.altervista.org/desulf/desulfator.pdf
The power source of above is the battery itself and a battery
charger is needed separately when to use because the battery
is discharged while desulfating and becomes empty as the
desulfation goes on.
I happened to find a patent below when searching the Net
and it explains about the actual frequencies and the current.
Patent: Pulse generation device for charging a valve-
regulated lead-acid battery
https://patents.google.com/patent/WO2004070909A1/en
The important figures are claimed as below.
4. A pulse generation device as claimed in claim 2,
wherein said first frequency is in the range of 50 kHz
to150 kHz and said second frequency is in the range
of 10 Hz to 500 Hz.
5. A pulse generation device as claimed in claim 1,
wherein said pulses are square wave pulses.
6. A pulse generation device as claimed in claim 2,
wherein the first frequency pulses have an on time
in the range of 1 to 10 μs and an average current
in the range of 20mA to 60 mA.
When I was reading the contents, I got an idea to make a unique
desulfator which can charge and desulfate the battery at the
same time. My idea is to modify an AC adapter for a laptop PC.
Many of those AC adapter has a out put of DC 19-20V range
with a PFC circuit to meet the regulation of the power factor.
Most of those stop the PFC function when the load is small
and the deactivation is useful to get the second frequency
explained at the number 4.
Below is the result of 4 days after the desulfation was started.
I also took a photo just when started but I can't find it now.
I remember almost all the part was white then.
You can see how the sulfation was decreased. Actually the
battery became quite OK to start the engine easily.
Before the desulfation was done, no matter how I charges the
battery using a regular charger,it was impossible to start the
engine.
