# Unusual charger



## palmer_md (Jul 22, 2011)

probably one of the "BadBoy" chargers.

http://www.evalbum.com/tech/bonn_charger.html


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## dcb (Dec 5, 2009)

I wouldn't market it, but I like it  Bout as simple as it gets. How big are those capacitors, and what AH and voltage battery pack did it come with?

edit: I don't think it is a BONN, it limits current via the caps, perhaps set up as a voltage doubler, I was just experimenting with one of these in ltspice, nice to see the idea wasn't completely crackpot.

Looking at that bridge (and chord), it isn't a LOT of amps.


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## evmetro (Apr 9, 2012)

dcb said:


> I wouldn't market it, but I like it  Bout as simple as it gets. How big are those capacitors, and what AH and voltage battery pack did it come with?


I don't know any specs on it, but the remains of the kit that i bought had an AC 35 and a 1238 6501 controller. The guy threw in a donor chassis to close the deal. I ended up going with a 1238 7601 and PFC 40 on that build. The numbers on those caps are right where they are glued together. I don't know a whole lot about battery chargers, but that lamp cord is telling me that it is not exactly a rapid charger...


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## dcb (Dec 5, 2009)

on each 60hz pulse the caps charge up and limit the average current (smaller caps=less average current), looks like it isn't a "doubler", all the caps look like they are in parallel (and I only see one bleed resistor), so it won't move any current if your battery is over ~170v (easy to make a doubler out of it though). Crude timer control, but better than nothing, probably OK for lead, needs better control for non-lead batteries or careful monitoring.


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## dcb (Dec 5, 2009)

Also, I don't know a lot about lead batteries, but I imagine they have a lot more series resistance than newer types, so this is probably waaaay to much capacitance for a non-lead battery charging from a 120 outlet, too much average current, you might be able to just unplug a few of them capacitors or even add them back in series though.


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## alvin (Jul 26, 2008)

Here is a thread that ran a few years ago.


http://www.diyelectriccar.com/forums/showthread.php?t=48691&highlight=variable+voltage+charger


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## Russco (Dec 23, 2008)

evmetro said:


> I got this thing a few years ago as part of an EV conversion kit that I got off craigslist, and never used it. Anybody ever seen these before? It looks pretty thrifty, Can it really be used to charge batteries?
> 
> 
> 
> ...


It's a series capacitor charger using a Harbor Freight voltmeter. The best thing about this charger is the neat carrying handle.


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## electro wrks (Mar 5, 2012)

All it needs is rattan mesh panels covering the side openings to complete the effect: proto steam punk?


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## dladd (Jun 1, 2011)

I've seen them on ebay. a quick search found this


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## dcb (Dec 5, 2009)

electro wrks said:


> All it needs is rattan mesh panels covering the side openings to complete the effect: proto steam punk?


maybe a tiki torch instead of a meter backlight?


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## jeffcoat (Apr 16, 2012)

The charger is the older version of this charger that they sell for an unconscionable $295. I came into possession of one of them a few years ago, and it had wire mesh screening stapled to both sides of it to keep fingers out of it. It does the job in a pinch, but the little piece of angled steel makes a weak heat sink for the rectifier.


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## nimblemotors (Oct 1, 2010)

That unit would pretty much be a disaster with anything but a 120v-144v lead-acid battery pack.

However, you can use it to generate DC from the AC power as input to a DC-DC converter to adjust the DC voltage as appropriate for the battery pack.


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## dcb (Dec 5, 2009)

lol, wouldn't you know it that Damien has done a video on it 

https://www.youtube.com/watch?v=FSDmzDuJ7HI

I will have to experiment with adding an ssr and a microcontroller for an onboard doubler for 120v->180v ~3amp charger. I figure that if I select the capacitance such that the current drops to 3 amps rms (1/10c) as the battery reaches 180v, then it will finish at a full (albeit longer) charge. Again, not something I would market though.


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## evmetro (Apr 9, 2012)

Thanks for all the replies. I had lots of fun reading the thread links and watching the video links. I stuck the charger back up on the shelf for some other chapter of life.


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