There are various devices that I rely on to do my research work on the bike - GPS device, smartphone (mostly for maps), camera. Three days has become the limit until I need a recharge somewhere. I carry four camera batteries and a 10,000mha power bank. Before the covid situation things were easier as I'd find a pub or cafe to get a recharge, or stay for the odd night at a YHA to wash clothes and recharge batteries. But that's a lot more difficult now.

So I'm looking at how I can become a more effective harvester of electrons and have two questions I'd appreciate the wisdom of the BB hive mind:

1. Is there a power bank that recharges itself very quickly from a mains socket? My smartphone has a fast charge feature, I'm looking for similar in the power bank itself, so it will absorb a decent amount of charge in an hour.

2. What's a good dynamo to USB charging device, for riding in the 10-20kph zone? Sinewave Revolution seems tried and tested, though the Igaro supposedly offers better performance - but it is of questionable reliability, not currently available and double the price of the Sinewave. Any others worth a look? How long do these things take to recharge a 10,000 mha power bank?

Anything else I should be thinking of? Is it unethical to stop at a church for a recharge like I do for water, if I put a couple of £ in the collection pot? Is solar out of the question in the UK?

JackT wrote: ↑Thu Jun 17, 2021 10:21 am 1. Is there a power bank that recharges itself very quickly from a mains socket? My smartphone has a fast charge feature, I'm looking for similar in the power bank itself, so it will absorb a decent amount of charge in an hou

This is more about the charger than the power bank. The power bank may have a limit on the current it will draw, but a bigger decent quality one will accept 2 or 3A I would expect. Any charger should have an output current rating on it somewhere. Look for one that will supply at least 2A, maybe 3, but be aware it might be a little bigger.

JackT wrote: ↑Thu Jun 17, 2021 10:21 am Is it unethical to stop at a church for a recharge like I do for water, if I put a couple of £ in the collection pot?

Seems like it'd probably be a reasonable approach:
https://www.quora.com/What-is-the-cost- ... mp-charger

TL;DR - it's a lot less than £1 for a full charge.

What's a good dynamo to USB charging device, for riding in the 10-20kph zone?

Really depends on what you want to pay for one - Forumslader is the best [as in delivers the most electrons] but enjoy your reading

https://www.swisscycles.com/list-of-hub ... c-devices/

Hadn't thought about churches as power sources of the electrical kind, maybe if you use them often enough, you could get rid of the GPS and rely on your moral compass.

For dynamo charging I used a USB-werk for a while and it appeared to be reliable. It has a small ballast battery to smooth current out which should stop finicky phones switching off the charging supply as they think its a power surge.

htrider wrote: ↑Thu Jun 17, 2021 12:58 pm For dynamo charging I used a USB-werk for a while and it appeared to be reliable. It has a small ballast battery to smooth current out which should stop finicky phones switching off the charging supply as they think its a power surge.

I've had generally good experiences with this, have one on both the bikes that have dynamos. Effective, simple, internal battery is a good thin just make sure it's not left flat for too long. Also watch for wires flexing with steering and breaking over time, best to keep the whole thing on the bars (probably a risk/point with most electronics like this).

Top tip about charging in a church and dropping some money in the box. Can be a good bet for water and chats with pleasant people. Pretty places. Some have cake and a donations box too. I always feel I should take my helmet off before I go in, is that odd? : )

How long do these things take to recharge a 10,000 mha power bank?

USB-Werk puts out 0.5Ah at around 12-15mph. So 20hrs to fill a 10,000mAh battery at that pace, plus a bit for losses.
I've kept a Garmin 820 (1000mAh), a phone for minimal use (2000? not sure) and a camera (1250mAh) topped up on tours with the USB-Werk w/o using a power bank, just a bit of care plugging things in during the day and then running the Garmin off battery when the lights are on. Those were tours when I generally rode all day though, and on road more than 50% of the time so pace high enough to get the 0.5Ah out. A 5,000mAh power bank and the USB-Werk could be good for covering all options?

Take two power banks
Get a phone with a high capacity battery, and/or ability to take spare battery

Solar panel ?

I took a pair of Charmast 20mAh on the AMR and used them to charge GPS, phone and my lights. If you get the right one you can get 18w PD or Quickcharge 3.0 that charge, err, quicker! Only about £25 and you can charge 3 or 4 devices at the same time.

https://smile.amazon.co.uk/dp/B0892B32L ... B1M4QHSR2S

Not necessarily recommending that model but its an example. Mine came in a nice mesh bag and a selection of different cables. Obviously get a PD/QC3 charger to match.

I'm with a 20,000mAh anker power bank. Was more than enough on a 8 days trip that included 4 days of riding with the phone used for navigation. Riding roughly ~50km per day with ~4 hours of actual riding with similar amount of breaks in between. Having a proper GPS should reduce the power consumption significantly, isn't it?
Now I have a GPS, and also cycle with a compact camera. I think the power bank will handle week long cycling trips with ease.

I use one of these fast chargers with USB C powerbanks

https://www.anker.com/ca/products/varia ... 2/A2625121

JackT wrote: ↑Thu Jun 17, 2021 10:21 am 1. Is there a power bank that recharges itself very quickly from a mains socket? My smartphone has a fast charge feature, I'm looking for similar in the power bank itself, so it will absorb a decent amount of charge in an hour.

This is my approach.

Two options.
My opinion, several smaller packs.
Each pack charges at approx 18W.
Not the absolute quickest; however, I prefer several smaller packs for redundancy.

I have three of these
How many I take depends on the time away from mains.

Anker PowerCore Essential 20,000 PD 20W https://www.amazon.co.uk/dp/B08LG2X98F/ ... UTF8&psc=1

The quickest I could find is this anker USB-C PD pack.

Anker PowerCore III Elite 25600 PD 60W
https://www.amazon.co.uk/dp/B08S6YRTDN/ ... UTF8&psc=1

And a suitable USB-C PD charger.
However, the pack is large, expensive, and single point of failure.

Charger
For either option
MINIX 66W Turbo 3-Port GaN Wall Charger 2 x USB
https://www.amazon.co.uk/dp/B08M3L8BFT/ ... UTF8&psc=1

Thanks all for the excellent advice - much appreciated.

@Asposium's multiple power banks and special charger with two or three 18W sockets is the way forward for maximising the use of brief stops at cafes etc. The mass is in the battery cells themselves, so two 10,000 mAh won't be dramatically heavier than one 20 mHa unit, but provides flexibility and redundancy in case of failure.

Charmast seems to be a budget conscious choice, so good to hear from @johnnystorm that they work.

Not sure I've reached a conclusion on which dynamo to usb converter is the best choice, but charging to a power bank rather than a device seems to be highly recommended. There doesn't seem to be a vast amount of difference in power output, so probably comes down to things like price and build quality.

Not sure I've reached a conclusion on which dynamo to usb converter is the best choice, but charging to a power bank rather than a device seems to be highly recommended.

That's always the advice Kerry at K-Lite gives with regard to maximising efficiency Jack.

Bearbonesnorm wrote: ↑Wed Jun 23, 2021 10:36 am

Not sure I've reached a conclusion on which dynamo to usb converter is the best choice, but charging to a power bank rather than a device seems to be highly recommended.

That's always the advice Kerry at K-Lite gives with regard to maximising efficiency Jack.

More efficient than direct charging or just more adaptable? Interested if it's more efficient, how does that work / any links?

More efficient than direct charging or just more adaptable? Interested if it's more efficient, how does that work / any links?

I shall try and find some old emails in which Kerry explains his thinking but I recall that he does say it's a more efficient use of power rather than just more adaptable, etc.

jameso wrote: ↑Wed Jun 23, 2021 9:11 pm

Bearbonesnorm wrote: ↑Wed Jun 23, 2021 10:36 am

Not sure I've reached a conclusion on which dynamo to usb converter is the best choice, but charging to a power bank rather than a device seems to be highly recommended.

That's always the advice Kerry at K-Lite gives with regard to maximising efficiency Jack.

More efficient than direct charging or just more adaptable? Interested if it's more efficient, how does that work / any links?

I don't think it's more efficient - there's something like a 10% loss of energy in all transfers, the energy is lost through heat amongst other things.

As stated by some else above, having a couple of powerbanks is more resilient and copes with redundancy.

whitestone wrote: ↑Wed Jun 23, 2021 9:31 pm

jameso wrote: ↑Wed Jun 23, 2021 9:11 pm

Bearbonesnorm wrote: ↑Wed Jun 23, 2021 10:36 am

Not sure I've reached a conclusion on which dynamo to usb converter is the best choice, but charging to a power bank rather than a device seems to be highly recommended.

That's always the advice Kerry at K-Lite gives with regard to maximising efficiency Jack.

More efficient than direct charging or just more adaptable? Interested if it's more efficient, how does that work / any links?

I don't think it's more efficient - there's something like a 10% loss of energy in all transfers, the energy is lost through heat amongst other things.

As stated by some else above, having a couple of powerbanks is more resilient and copes with redundancy.

That's what I was thinking, charging losses and you've added a step in the process, but Kerry at K-lite is far better with electronics than I am. Just interested as I've always charged things direct. It' a bit of a juggle but I'm more likely to get the charging right in the day vs once stopped for the evening, fall asleep and forget to plug the Garmin in.

jameso wrote: ↑Wed Jun 23, 2021 9:42 pm

whitestone wrote: ↑Wed Jun 23, 2021 9:31 pm

jameso wrote: ↑Wed Jun 23, 2021 9:11 pm

Bearbonesnorm wrote: ↑Wed Jun 23, 2021 10:36 am

Not sure I've reached a conclusion on which dynamo to usb converter is the best choice, but charging to a power bank rather than a device seems to be highly recommended.

That's always the advice Kerry at K-Lite gives with regard to maximising efficiency Jack.

More efficient than direct charging or just more adaptable? Interested if it's more efficient, how does that work / any links?

I don't think it's more efficient - there's something like a 10% loss of energy in all transfers, the energy is lost through heat amongst other things.

As stated by some else above, having a couple of powerbanks is more resilient and copes with redundancy.

That's what I was thinking, charging losses and you've added a step in the process, but Kerry at K-lite is far better with electronics than I am. Just interested as I've always charged things direct. It' a bit of a juggle but I'm more likely to get the charging right in the day vs once stopped for the evening, fall asleep and forget to plug the Garmin in.

From what I've understood it's that power banks are better at taking more of the available charge coming from the dynamo than devices, some of which get confused (or worse) when the current (or do I mean voltage??) goes up, down and stops and starts, as it does coming from a dynamo at different speeds. James, I believe the e-werk has its little cache battery for exactly this reason. A power bank is just a larger reservoir.

I see - so a power bank would soak it all up, not just the output over a certain level.
If you didn't have a cache battery in the charger or a pass-through buffer cell I understand the benefit. e.g an iphone won't handle varying charge current and the Garmin would go into auto power down when you slow down which makes charging in use impossible.