Simplest Charger/desulfator Ever

Intro: Simplest Charger/desulfator Ever

This charger can charge almost any battery type at any voltage. It desulfates lead acid batteries as well. It works quite well. Be warned tho, it contains lethal voltages. If powered by 120vac it can get up to 170 volts and 340 volts on 220vac.

Step 1: Materials:

Ac run capacitor Rectifier or 4 diodes Switch(optional) Electrical cord

Step 2: Schematic

Step 3:

As you can see it is quite simple. The capacitor couples the battery to the mains as well as limiting the current. At 120vac it charges at 1 amp for ever 22uf in capacitance, 13 uf at 240. The switch is merely convenience so i dont have to unplug and replug. Then the diode bridge rectifies it to dc.

Step 4: Usage

it works in a way that if the battery is sulfated or weak etc. it will always charge at the preset amps. So if the battery is only taking 5 amps at 12 volts and u have it set for 10 amps, it will raise its voltage until it is charging at 10 amps. At 120vac the charging voltage could go up to 170vdc. 340 with 240. It also pulses at 120 herts which desulfates the lead acid batteries. It should also be noted that this is a universal charger and will charge any voltage battery. It should also be noted that the is no protection against over charging and if it is left on the charger when the battery is already charged it could damage the battery.

Share

    Recommendations

    • Plastics Contest

      Plastics Contest
    • Optics Contest

      Optics Contest
    • Audio Contest 2018

      Audio Contest 2018

    53 Discussions

    0
    None
    10kvaliant

    Question 2 months ago on Step 3

    What is the minimum and maximum input voltage?
    I have a 500 microfarad capacitor and a rectifier of 60A 1200v. Will it work? Waiting for your response.
    Thanks

    15342456843251815164721.jpg
    1 more answer
    0
    None
    HarijantoH10kvaliant

    Answer 5 weeks ago

    500uF will deliver 38A @230V or 20A@ 110V system. It's too high and dangerous for you and your battery. Try to find 30~80uF (230V system) to deliver max 2 - 6A for your battery. Best if you could use Air conditioner (oil filled/wax ) capacitor for mediocre battery treatment. similar capacitor can be seen here:

    https://www.banggood.com/15-50uF-Motor-Capacitor-CBB65-450VAC-Air-Conditioner-Compressor-Start-Capacitor-p-1135343.html?gmcCountry=ID&currency=IDR&createTmp=1&utm_source=googleshopping&utm_medium=cpc_elc&utm_content=frank&utm_campaign=pla-elc2-id-pc-0511&gclid=Cj0KCQjww8jcBRDZARIsAJGCSGsNs4QTTV01aKDeEk562kWbSwj2qcKZ9mA9xjPk65uMS7ITOsC2lzoaAoPeEALw_wcB&ID=514852&cur_warehouse=CN

    The rectifier can be used.

    0
    None
    Firemnted

    2 months ago on Step 4

    This is the latest one I built!

    E0BFA44B-82D4-4F1A-97ED-8F1DAB6EEDAB.jpeg
    0
    None
    drchasbrown

    7 months ago

    I built one of these. It really brings desulfated wheelchair batteries back from the dead.

    0
    None
    ARON751A

    1 year ago

    Capacity lead battery charger /desulfator can charge from 0v to full charge



    0
    None
    CyberR

    1 year ago

    I've now rebuilt this desulfator with a switch that disconnects both the live and neutral mains lines and added a small PSU board from an old phone charger that runs an LED. I now plug this into a 24hr timer set to turn on for 30mins then off for 1 hour.

    I'm currently looking into adding a temperature activated switch that will sound an alarm and cut power to the desulfator side if the temp rises too much. I am however trying to keep it as simple as posible with as little cost and electronic assembly as possible.

    0
    None
    willdbill

    2 years ago

    This thing dose it work and how long a charge do you nead to discharg recharg how many times if i dont get a reply i will asume the op has friyed hime shelf

    0
    None
    chris2u

    2 years ago

    This circuit is LIVE and highly DANGEROUS !!

    Full mains voltage is available at the battery terminals unlike chargers that use a mains frequency or switch mode transformer..

    Contacting any of the wiring or connections with a grounded body (human or otherwise) could prove fatal.

    Maybe an experimental project for the lab.....But not where humans or animals could come in contact with it in any way..

    0
    None
    CyberR

    2 years ago

    erm... another update. I... err... I may have killed the batteries, used them in an R/C car in parallel for more amps. Long story short, the rear drive of the R/C got bust/destroyed so the car in storage till i could rebuild. took it out today to check something out and, like a Doofenshmirtz, had forgot to disconnect the SLAs.

    Going to have to scrounge parts and rebuild defulfator (stripped it for another project) and a try a few other techniques first then this. fingers crossed.

    0
    None
    StephanM20

    2 years ago

    I love simple designs. However, I see some things I don't like:
    Protection: If the capacitor fails with a shortcut, -I don't even want to imagine that. A fuse it the minimum you should integrate.

    Ripple current of capacitor not regarded. Standard capacitors will can ripple currents about 2A. You want 5-10A. Make sure you don't cook the capacitor.

    Nobody guarantees that the battery is charged by nominal current! The current will be mainly determinded by battery resistance and resistance of the rest of the circuit.

    No overload protection. Yes it might remove reversable sulfatation, because this is usually done by applying overvoltage by a limited time. Overvoltage for a longer time will kill the battery quickly.

    1 reply
    0
    None
    Thomas055

    Reply 2 years ago

    This looks incredible! Definitely trying it out. Thanks!

    0
    None
    rmargate

    2 years ago

    can i use it to charge a 48v sla battery pack of my ebike?

    1 reply
    0
    None
    Lionhearmatrix

    2 years ago

    Hi guys. I'm on 240V here and have cap from an old microwave (0.97uF, 2400VAC). Which rectifier or which diodes should I use? Thanks

    0
    None
    CyberR

    3 years ago

    can't get hold of a starter cap however I do have a cap from a microwave. Would I be able to use this instead? We use 240v 60Hz mains which is also what the caps rated at?

    3 replies
    0
    None
    CyberRCyberR

    Reply 3 years ago

    Gone ahead and created the circuit using the high-voltage microwave cap rated @ 0.72uF 2100v ac I have and a bridge rectifier from a dead PSU board and added a light so can see instantly if circuit is live.

    The results
    No bang!!! That's a first.

    2 x 12v 2.9Ah SLAs
    3hrs on charge : not charging.
    3hrs on this circuit : now charging.

    I'm now alternate the batteries 1hr on 1hr off.

    Oh and I never have more than one battery hooked up at anytime when charging or desulphating. I'm not that stupid lol

    0
    None
    CyberRCyberR

    Reply 3 years ago

    A quick update. I still don't know the history of the 2 SLA's other than they were stone dead when salvaged from a bust electric recliner. However they are now back up and running thanks to this simple circuit.

    Still running strong even when they've been in heavy use and completely drained they've still recharged on a normal charger.

    0
    None
    steve000CyberR

    Reply 2 years ago

    Many thanks for your update I'll attempt to make this myself now

    0
    None
    ZoranKoco

    3 years ago

    I have questions about your success too. I made this charger long time ago, and I was experimenting only with one lead acid battery, 12V 55 Ah witch wasn't in use for long time, but I'm not sure that I improved it from sulfatization. However it was charging with this charger, my question is does it really work like desulfator?? I would like to read more comments of your expirience.

    0
    None
    Toga_Dan

    3 years ago

    op, are you still following this? I have questions about your success rate. I'm also concerned about that much voltage on a 12v. Did you track battery temperature? Did you ever put this on an oscilliscope? I wonder what %of a second there is voltage to battery. I suppose that is contingent upon capacitance. A small cap only sending voltage thru for a brief moment., etc.