Charging phone from 5v wiring

LithiumFan

Finding my (electric) wheels
Jan 6, 2019
22
5
Herefordshire
Hi,
I use my phone as GPS on long rides and it drains the phone's battery really quickly. I've found a thread on tapping into main battery terminal with a 36-12v converter then using a car 12v outlet but can you just tap into any 5v wiring on my kit, say using the lighting wiring or that powering the display? I'm very unlikely to want to charge the phone in the dark.
 

Fordulike

Esteemed Pedelecer
Feb 26, 2010
3,693
1,466
Tyne and Wear
Hi,
I use my phone as GPS on long rides and it drains the phone's battery really quickly. I've found a thread on tapping into main battery terminal with a 36-12v converter then using a car 12v outlet but can you just tap into any 5v wiring on my kit, say using the lighting wiring or that powering the display? I'm very unlikely to want to charge the phone in the dark.
I would be reluctant to tap into the 5v supply to power a phone, as it may affect the controller's operation if it drags the voltage down due to current draw.

How about one of these buck converters, with a USB end. No good if you got an iPhone or one with USB-C though.

DC Step Down Buck Converter 12V 24V 36V 48V (11-60V) to 5V 3A Micro USB Adapter
 
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Deleted member 33385

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I would be reluctant to tap into the 5v supply to power a phone, as it may affect the controller's operation if it drags the voltage down due to current draw.

How about one of these buck converters, with a USB end. No good if you got an iPhone or one with USB-C though.

DC Step Down Buck Converter 12V 24V 36V 48V (11-60V) to 5V 3A Micro USB Adapter

That's very useful! I could charge camera batteries with that - they only last 45 mins each (you get two) and some of my journeys are 4 hours long. Cheers!
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
8,718
3,460
Basildon
The controller's 5v regulator can supply 100 mA. the hall,sensors, throttle, speed sensor and PAS take about 50 mA, which doesn't leave enough to cgarge your phone.

You should use a proper 36v USB module. something like this:
There are cheaper ones on Ebay and ALiexpress, but if that type fail, you'll get battery voltage dumped into your phone, so better to use the more ezpensive type above.

this looks like the same one cheaper on Aliexpress.

this one mentions protection too. i din't know if it's the same as Fordulike's:
 
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Deleted member 33385

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The controller's 5v regulator can supply 100 mA. the hall,sensors, throttle, speed sensor and PAS take about 50 mA, which doesn't leave enough to cgarge your phone.

You should use a proper 36v USB module. something like this:
There are cheaper ones on Ebay and ALiexpress, but if that type fail, you'll get battery voltage dumped into your phone, so better to use the more ezpensive type above.

Thank you vfr, that is very useful indeed. That's now on my Amazon shopping list. I certainly don't want anyone here to miss any of the gory details of my next crash!
 

GSV3MiaC

Pedelecer
Jun 6, 2020
130
86
You can get a humungous USB power bank for peanuts these days, which will charge your phone, camera, laptop or whatever, even away from your bike. No wire cutting, warranty invalidation, or technical skills required.
 

snafu

Pedelecer
Dec 15, 2020
44
47
You can get a humungous USB power bank for peanuts these days, which will charge your phone, camera, laptop or whatever, even away from your bike. No wire cutting, warranty invalidation, or technical skills required.
While you are correct (This is the method I use). But be prepared to take capacity claims with a "Very large" pinch of salt.

I have a quite old no brand unit rated at 12,000mah which by my best guess in use is nearer 5,000mah I also have a "Freeloader Sixer" rated at 6,000mah which will easily charge more than the no brand model and appears to be telling me the truth as far as capacity goes.

I think most on here have a reasonable knowledge of volts, mah, ah,wh etc so items such as this...

Should be viewed with some scepticism. ;):)

I do like the look of the unit shown by Jim though, I may have to take a closer look at that.

TTFN
John.
 

jimriley

Pedelecer
Jun 17, 2020
230
140
While you are correct (This is the method I use). But be prepared to take capacity claims with a "Very large" pinch of salt.

I have a quite old no brand unit rated at 12,000mah which by my best guess in use is nearer 5,000mah I also have a "Freeloader Sixer" rated at 6,000mah which will easily charge more than the no brand model and appears to be telling me the truth as far as capacity goes.

I think most on here have a reasonable knowledge of volts, mah, ah,wh etc so items such as this...

Should be viewed with some scepticism. ;):)

I do like the look of the unit shown by Jim though, I may have to take a closer look at that.

TTFN
John.
On closer inspection, that one is even better than mine, it's double usb with a switch. Mine is single, unswitched. I have a fuse and switch on the 36v feed. I've also powered a horn and front and rear+brake lights. I put a dollop of vaseline in the usb socket and tilt the usb unit downwards to keep the rain out. Got a sizeable power bank from lidl last week btw.
 

LithiumFan

Finding my (electric) wheels
Jan 6, 2019
22
5
Herefordshire
Hi,

Thanks all. Very helpful. I tried making one using a pcb board module as suggested but after trying to test the output and couldn't get a voltage I decided not to risk it. I bought a potted one as recommended and connected it to my battery with an XT60 Y harness and it works a treat. My phone stayed at 100% power for my whole test ride today.

I don't have any warranties to worry about as my 4 ebikes are all conversions with the same XT60 plugs on all of them to fit my 3 different batteries. Apart from the small cat's cradle of wires, the buck converter set up is much lighter than a power pack and all the bits sit in my battery bag out of the weather with just the USB cable to get to the phone. I can use it on all my bikes no matter which battery I use. There is no room on the handlebars for anything else. I converted this 2nd hand bike last year and it works a treat.
XT60 harness.png20210408_Thorn set-up.jpg
 
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snafu

Pedelecer
Dec 15, 2020
44
47
Following jimriley's recommendation I bought one of those "Dual USB power charging adapters" Wired into the battery terminals on my Vengeance controller. Easy bit of DIY and I have to say it works great. :) Going to get another one for my Bandit. Big thumbs up.

Thanks for the link Jim.

TTFN
John.
 

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