52 VDC to USB (3 volt?) converter

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craneplaneguy   10 kW

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52 VDC to USB (3 volt?) converter

Post by craneplaneguy » Aug 07 2018 7:00pm

I found myself in the ridiculous position this weekend of having 17.5 AH's of fully charged 52 VDC battery, and with a dead cell phone. I had my 12 VDC phone charger, while I realize there are converters for 12 to 52 VDC, but I was wondering if there is a very light and simple way to charge my phone off my 52 VDC battery? I'm sure there is, but searching has not turned up anything.

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MadRhino   100 GW

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Re: 52 VDC to USB (3 volt?) converter

Post by MadRhino » Aug 07 2018 7:21pm

Universal ebike usb charger for any battery 36v to 100v.

https://m.fr.aliexpress.com/item/328674 ... form=msite
Make it fool-proof, and I will make a better fool.
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amberwolf   100 GW

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Re: 52 VDC to USB (3 volt?) converter

Post by amberwolf » Aug 07 2018 7:32pm

Your regular wall charger for the phone may well run right off your ebike battery.

Hook up the AC prongs to the battery + and -, and see if it works. :)

More than half the little SMPS (lightweight) type AC adapters for things I've tried have worked on DC above around 50V.

I used 15vDC output 100-130VAC input wallwarts on both CrazyBike2 and an early version of SB Cruiser to run all the LED lighting on them, for example.


The heavy (transformer) types can''t, but there's not a lot of those made these days.

craneplaneguy   10 kW

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Re: 52 VDC to USB (3 volt?) converter

Post by craneplaneguy » Aug 08 2018 10:14pm

Thanks guys, I'll try that wall charger idea first, it'd be easy enough to make up a little adapter for it.

Today I loaded up for a big ride in another state in a very remote area (think grizzly bears) and on the drive there realized that I had forgot my charger. I had brought my inverter, to use on my upgraded 12 VDC port in my Toyota (now good for 25 amps, stock is only 15, ran new wiring and got a heavy duty marine high quality socket), tools, water, and everything else except the frigging charger. I was too far away to go get it, luckily the batteries were well up to the job without a fresh charge. No worries about a dead cell phone battery as I was out of coverage anyway, but I want to be ready for next time.

markz   100 GW

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Re: 52 VDC to USB (3 volt?) converter

Post by markz » Aug 08 2018 10:49pm

Go to thrift stores and buy them usb converters for cheap, a couple bucks, and try it.

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