moped with 6v sytem but i need 12v for phone charger. idea's & suggestions pls

Hi, i run a 1980's suzuki 50cc moped. its electical system charges a 6v 2amp battery. I need to charge my phone from the moped battery using a car cigerete phone charger that is designed to operate off a 12v system. the phone charger runs from 12 volts and its output is 5v 500ma.  i tryed connecting the charger strait to the moped battery but nothing happens. not even a lower voltage is shown!  the phones battery is 3.7 volts.  the phone will only charge if i use the phone charger on a 12 volts supplie. 

is there a device i can use as a work around to connect strait to a 6v battery that will then boost output to 12v in order i charge my phone.

please help as i need my phone for my work. the phone is a xda zest. with a built in gps navigator that i want to use all of the time on my moped.

thanks for replies in advance.

sort by: active | newest | oldest
selectauto (author) 5 years ago
Well just want to say thanks so much for your help as i said im a bit of a electonics dummy and would have no idea how to build one of these power boosters without being shown first and then it would still be a litte bit hit and mis with me. what fuse should i use with this booster? any idea?
Honus5 years ago

Here's a 6v to 12v boost converter circuit that will provide 800mA current-
selectauto (author)  Honus5 years ago
Hi, thanks for youe info given so far! after reading your comment i bought a booster from ebay. see link below. Im going to be using it to charge my power hungry phone via a 12v phone car charger the type that plugs into your cigar lighter. the moped runs a 6 volt electrical system. Im not veay up on electronics and would like to ask your advice on how i should connect this little booster. (Its so small)

it has a posative in and posative out and ground connections. im guessing cause there are no intructions with it, that i connect the red wire + from the posative power source to the posative + in connection and use the posative + out connection the phone charger. and i spose the ground is to connect to the bikes chassis! I reckon i leave the negative wire alone and use this circait as a in line on the red wire only.

Does that sound about right to you. please comment. thanks,

Happy to help! It looks like you will connect the IN+ to your 6V+ and then connect GND to your chassis (assuming the chassis is connected to the battery negative terminal.) Then connect your 12V+ to OUT and 12V- to your chassis ground.
selectauto (author)  Honus5 years ago
hello honus thanks for getting back to me on this. should i include a fuse and perhaps knowing that a diode only allows electic to run in one direction, should i fit a diode as well just in case this little booster goes wrong?
A fuse can't hurt but I don't see any need for a diode.
lemonie5 years ago
You need a voltage regulator, this sort of thing: