What battery pack?

[Laid Back Rich]

Make sure you get one that takes a micro/mini USB input. Some use a smaller jack-plug that means you can only charge them from the mains with the wallwart they come with - so no use for dyno-charging.
I have the Teck Net 5000mAh, which does two charges of my Samsung III, and charges fine off an e-werk or Axa light.

well thanks this forum is a mine of useful info, I think for £14.97 at amazon I will go with your recommendation Chris

[Chris S]

Make sure you get one that takes a micro/mini USB input. Some use a smaller jack-plug that means you can only charge them from the mains with the wallwart they come with - so no use for dyno-charging.
I have the Teck Net 5000mAh, which does two charges of my Samsung III, and charges fine off an e-werk or Axa light.

well thanks this forum is a mine of useful info, I think for £14.97 at amazon I will go with your recommendation Chris

 

Pssst... if it blows up, you didn't see me, I wasn't here...

[wilkyboy]

The Anker Astro 3E seems to get good feedback on Amazon, but concerned if it's really tough enough to bounce around on a bike for long periods.

I use this 10Ah pack -- I bought it in November last year.  The capacity is substantial and I can run track logs on my iPhone while charging the phone at the same time (back before I had a GPS).  I can now charge BOTH iPhone and GPS at the same time (two USB ports, see).  And it will charge while being charged (although I haven't got a dynamo yet, so not sure about charging in that scenario).  It charges from a micro USB.

I bought a variety of very short (2-inch) USB cables on Amazon for charging things in my bag, as well as a longer USB cable with a 90-degree mini-USB plug for charging the GPS while it's mounted on the bars.  I can charge the lot on a 200 and finish with fully-charged equipment and about three-quarters of the battery pack remaining.

It comes with a nylon sleeve that I think is quite canny: it's layered mesh and has a 3D profile, so protects the unit from bashes and clanking around in the bottom of the back, because it's got quite a heft, although it weighs almost nothing, because it's a nylon mesh.

Works for me, although it is quite heavy (as most batteries are).

[Phil W]

I have ewerk and cache battery.  I used the supplied extension cable, and run it under my top tube to my saddlebag where the week and cache battery sit. I have an old non mapping farming, which is fine during the day. I prefer my Navtech mapped bryton during the night. Both GPS will fully charge from flat in about 4 hours of riding. With run times of 15-16 hours, means have one charged and ready is easy. I don't use the charger when I have the light on.

[RobW]

I have ewerk and cache battery.  I used the supplied extension cable, and run it under my top tube to my saddlebag where the week and cache battery sit. I have an old non mapping farming, which is fine during the day. I prefer my Navtech mapped bryton during the night. Both GPS will fully charge from flat in about 4 hours of riding. With run times of 15-16 hours, means have one charged and ready is easy. I don't use the charger when I have the light on.

Interesting ta. Was looking at ewerk, but now there's a new Synotec version with integrated USB charging output, so will see how that works out.

[Dave_C]

Well this thread is very usefull. I have ordered a crossbar bag from Wiggle and was initially looking at this from Maplin:

http://www.maplin.co.uk/9000mah-portable-power-bank-for-mobile-devices-636068

But the PowerGen looks good and the TeckNet looks even better.

I take it the TeckNet can be charged from a standard dynamo, I have the 3N80 Schimano dynamo.
To date I have an 8 AA cell pack from a childs broken remote control car giving 9.6v to power the B&M lights on my bike with no dymano.

I just have to butcher a spare mini usb lead to connect to the output from the dymano.

[Feanor]

Haud on there! You can't just connect your dynamo to the battery pack with a butchered USB cable!

Ye'll bla' it up.

Them dynamos can give out a surprisingly high joltage, especially at the speeds you will be going at

There are products available to provide USB charging off a dynamo, but they  are more sophisticated than a butchered cable.

[RobW]

Haud on there! You can't just connect your dynamo to the battery pack with a butchered USB cable!

Ye'll bla' it up.

Them dynamos can give out a surprisingly high joltage, especially at the speeds you will be going at

There are products available to provide USB charging off a dynamo, but they  are more sophisticated than a butchered cable.

Yep - minimum you'll need is a voltage reg in there. It's doable, buddy of mine does a lot of homebrew electronics and was going to make me one until the new Syno light came out with USB power output. But it's more than just a cable

[Kim]

Yep - minimum you'll need is a voltage reg in there. It's doable, buddy of mine does a lot of homebrew electronics and was going to make me one until the new Syno light came out with USB power output. But it's more than just a cable

As well as a voltage regulator you'll need a rectifier (the dynamo output is AC), and some sort of limiting so the off-load voltage (ie. when the battery reaches full charge halfway down a hill) doesn't exceed the rating of the regulator - I'd advise designing for 100V on the input.  A simple zener diode clamp isn't sufficient for dissipating the power produced during a fast descent; you'll need to crowbar the dynamo (handily, it's a AC constant current source) with a pair of low-voltage-drop thyristors or something.  Add heatsinks, fuses, reservoir capacitors and output short circuit and over-voltage protection circuits to taste.

If the above paragraph doesn't make sense, I advise against connecting anything homebrew to your expensive gadgets.

[Dave_C]

Nah its all good. I will build a simple rectifier and then use a hefty regulator with poss a couple of smoothing caps between the bridge and the regulator. Its a constant half amp output I've found. I'll speak to a couple of designers at work about s/c protection. Also might put in a simple resistor voltage ref off the output to feed back into an output switch.

[Kim]

Nah its all good. I will build a simple rectifier and then use a hefty regulator with poss a couple of smoothing caps between the bridge and the regulator. Its a constant half amp output I've found.

Yeah, but only when there's somewhere for the half amp to go.  At speed, that's a fair amount of heat to dissipate if there isn't a battery to charge.  Otherwise as the current falls you have to allow the voltage to rise without breaking anything, or pull it right down so the half amp doesn't give you much power.

[Dave_C]

I may just ride with the lights on and also install a handlebar switch then.

[Pmathews]

Back half a step.  What tricky boxes are you using to charge the batteries with?  E-werks are ferociously expensive.

Peter Mathews
pmathews@alphalink.com.au
m: 0439992130 p: +61398906089 w: +61399052192
Pres, Audax Oz

[marcusjb]

Back half a step.  What tricky boxes are you using to charge the batteries with?  E-werks are ferociously expensive.

E-werks indeed are ferociously expensive - though they have recently launched a lower cost USB voltage only unit (the original E-werk allows you to select voltages and amperage).

I am an E-werk user and, in general, I am very happy with it. 

I can see that with things like the Luxos light (with an in-built USB charger) and other lights that the E-werk will fade out of memory in the long term. 

[Somnolent]

Back half a step.  What tricky boxes are you using to charge the batteries with?  E-werks are ferociously expensive.

Peter Mathews
pmathews@alphalink.com.au
m: 0439992130 p: +61398906089 w: +61399052192
Pres, Audax Oz

Me, I'll be using some Aussie technology 
(Pedalpower SIC - rectifier and smallish cache battery all in one)

[L CC]

If we can get one, we'll have a Luxos.
Otherwise we'll discuss our options- his e-werk, my ree charge, our Axa light or just batteries and wall sockets. (There is a high chance we'll have at least one night in a hotel).

[Andrew]

There's a French made e-werk-a-like charger that's got a couple of good reports on the French forum. Cheap enough at €30ish to be worth a punt.



http://eurecart.free.fr/

[Pmathews]

It's cheap enough to be worth a go.  Less than Oz$50 including delivery.  I looked at bits and pieces necessary to jig together a similar device over the weekend and this is very cost effective for something which is up and running.  My interest is to be able to charge phone, Garmin and batteries, not only on LEL but also for the preceding month when Jane and I will be cycling touring (roughly E2E).

I'll report how it goes,

Peter

[Andrew]

My interest is to be able to charge phone, Garmin and batteries, not only on LEL but also for the preceding month when Jane and I will be cycling touring (roughly E2E).

One guy on the French forum reported that it wouldn't charge his Blackberry. So I'd imagine then same would be true of (some?) smartphones, and the iphone maybe. He resolved it by charging a cache battery to charge the blackberry.

Best of luck with the experiment!

[LeeW]

I'm using a Deben tracer 12v 8amp/h battery (see http://www.deben.com/lithium-polymer-battery-packs.html), I am very happy with it, it has 12v output.  I use it to power my headlights (which is 12v) and also charge my phone and Garmin via a car USB adapter.  Don't think it can be charged by a dynamo though.

[RobW]

Slight variation to the original topic ....

The TechNet (or similar) pack will be my backup-up power source, able to charge phone and run stuff for a while if dynamo dies.

My backup light (at present) is a Lezyne which takes 18650 cells (very bright light, use it as my everyday riding light and really like it). The USB port is rather safely hidden though when mounted, so I'm not sure if I can charge direct from the TechNet and use it at the same time if I need to go to backup. I'll test that idea shortly but fairly sure it may not work, and may allow water in with the rubber seal out while riding even if it does work.

Next idea was a small - USB connectable cradle that could charge an 18650 cell from the TechNet whilst Lezyne is in use with one of my spare cells. Have seen very few of those, all out of stock, and all only take 1 cell (I guess I could just buy 2 cradles as they are cheap).

But ... it also seems a roundabout solution to charge light batteries from a battery pack. Why not just run a light direct from the TechNet pack in an emergency. Anyone know of a light that can do this, run powered from a USB cable (even if wet weather), and give a really good light for riding at decent speeds, and preferably get a couple of nights worth from a fully charged 7AH pack?

[Somnolent]

....
(even if wet weather),
.....

IME USB connections don't like the wet.  Some work ok in the rain, but when you get home and dry everything out you find corrosion on the connectors and then things cease to work.
You may be able to molish something from sugru* that will improve things, but unlikely to get really good levels of waterproofness.

* http://sugru.com/videos/wtf-is-sugru

[RobW]

....
(even if wet weather),
.....

IME USB connections don't like the wet.  Some work ok in the rain, but when you get home and dry everything out you find corrosion on the connectors and then things cease to work.
You may be able to molish something from sugru* that will improve things, but unlikely to get really good levels of waterproofness.

* http://sugru.com/videos/wtf-is-sugru

Ok - that's a good tip thx, was worried about USB connections in wet weather. Will fall back to 1st idea and get a cradle that I can charge 18650 cells from TechNet in the dry of my Ortlieb bar bag

[Chris S]

To my mind, this is where the e-werk wins as a charging solution; it has very over-engineered connectors, designed specifically for keeping the rain and electrons apart.

[Andrew Br]

Will fall back to 1st idea and get a cradle that I can charge 18650 cells from TechNet in the dry of my Ortlieb bar bag

Converting chemical energy into electricity, back to chemical and then to electricity again is a pretty inefficient way of powering a light.
Can you either take a couple of spare cells for the battery and/or a charger to boost them at controls ?