USB SeatPost Charger Project

Is there anything out at the current time that allows you to charge a phone (or other electrical device) through a port on a roadbike?

If not, I'll be looking into starting a project to input a Lithium battery into a seatpost which can be charged (and hold it well) and would have a USB output to charge another device when on the move.

Daft idea?

Could suck the juice from Di2 port...

I made one of these for a recent trip to Amsterdam
http://makezine.com/projects/pedal-power-phone-charger/

The mobile phone charger worked, but not as well as hoped. If there is a lot of stop starting, the phone freaks out a bit... sometimes it will not charge or worse, drain the phone battery! If there is a long run of riding without stopping it will charge pretty well, but to get a full charge would take 4 or 5 hours of continuous cycling. I think it will need a bunch of modifications - perhaps if the dynamo charges a small battery that can keep the charge going while the bike starts and stops then the main problem of the phone freaking out will be addressed. Anyway, it was interesting and kept the phones going (there were a couple) while we were away from power points.

iphones need a special circuit - you can buy one from adafruit I think. I have an android phone...

from here:
http://www.en.tout-terrain.de/accessories/electric-power-supply/

Plug it into a dynamo hub

Thanks guys!

I'd be looking at stand alone battery pack rather then a dynamo (keeps it lightweight and hidden). Not as practical or sensible as a dynamo but it would be similar to a standard iPhone battery pack, just tucked inside a seat post

Pardon me for asking, but why not just get an extended battery pack (Mophie or similar) for iPhone?
The Dynamo+ThePlug solution makes sense, but isolating a battery pack inside a bike frame seems a bit... pointless. What am I missing here?

You're not missing anything. I used to find on my motorbike that a USB charging slot was so handy when riding - i.e. using a car satnav or charging a phone. I wanted to have the same option on a roadbike, but without the use of a dynamo. Just thinking about all those people running Di2 and EPS with a battery converted to run inside the post - so thought it may be nice have a port on the post for a rear light to charge if it dies on a commuting trip or just to juice something up when moving.

Not really a business idea, otherwise it would be dynamo related - just a slimline or rather bike fitting inside rechargeable power pack

You're not missing anything. I used to find on my motorbike that a USB charging slot was so handy when riding - i.e. using a car satnav or charging a phone. I wanted to have the same option on a roadbike, but without the use of a dynamo. Just thinking about all those people running Di2 and EPS with a battery converted to run inside the post - so thought it may be nice have a port on the post for a rear light to charge if it dies on a commuting trip or just to juice something up when moving.

Not really a business idea, otherwise it would be dynamo related - just a slimline or rather bike fitting inside rechargeable power pack

Extended battery life for lighting, good idea. I get that. Charging up the post battery would be part of trip prep, so no extra bother really.

Day-to-day though, remembering to either take out the seatpost to charge it, or plugging the bike itself in would be a PITA unless I was already running Di2/EPS and was in that habit anyway.
Not gonna happen any time soon though - I mean the whole beauty of a bicycle (to me) is that I don't have to fuel it up.

As an aside - Ty from GSC ran a Tout-Terrain 'The Plug' on his Stinner MTB (powered by a SON front dynamo hub) when he rode the Tour Divide this year. Haven't asked him how it held up yet, will hopefully do so soon.

So a seatpost with a removable battery pack could work nicely, rather then plugging in the 'whole' bike or removing the seatpost every use.

Weird and unpractical idea, but could be a handy feature>

Original idea was to install a USB point for rear light and one for front light (running cable through frame) with a removable battery pack (rather then removing both lights). When lights aren't being used through USB that power could be used for boosting other electrical devices

I get ~2,000 miles from a charge for my Di2- charge it in January every year.

Therefore taking the post out and putting it back in again is not a regular occurrence.

oh, ok I get what you want... Minty Boost - A small battery-powered USB charger
http://learn.adafruit.com/minty-boost
It has the iphone circuit in it already...

it would be easy to modify the circuit by adding more batteries in parallel - thus give a longer charge.

The dynamo works if you don't have access to power at the end of each day, but it makes a lot of noise, wears out tires, adds to fatigue and the ac to dc conversion loses a lot of power in excess heat...

I'm interested to see what you come up with...

I charge my Di2 by plugging my laptop into the little junction box that sits under the bars. I don't need to touch the battery or seatpost. I have the newer 11spd DA Di2 though.. because I'm worth it.

oh, ok I get what you want... Minty Boost - A small battery-powered USB charger
http://learn.adafruit.com/minty-boost
It has the iphone circuit in it already...

it would be easy to modify the circuit by adding more batteries in parallel - thus give a longer charge.

The dynamo works if you don't have access to power at the end of each day, but it makes a lot of noise, wears out tires, adds to fatigue and the ac to dc conversion loses a lot of power in excess heat...

I'm interested to see what you come up with...

I just ordered one of those minty boost kits. They look ace! I'm going to build one into an old puncture repair kit tin for times when the garmin / phone needs charging in the wild.