USB battery with genuine 'charge through' capability

[Polar Bear]

I'm looking for one for plugging into a USB Werk and taking juice whilst mllePB pedals along with her Garmin merrily chirruping away telling us where to go, literally!

If the experiment works I'll be installing an identical charging setup on my bike so that I can charge android phones on the go.

Ideally the battery would be relatively small so it can sit easily in the corner of a barbag with a couple of leads curling under the cover for both gps and USB Werk alike.

Small is good so lipstick types and slightly larger suggestions welcome. 

[Moleman76]

So you want to search for "usb battery pass-through charging" or something like that.

Limefuel did offer such devices; hard to tell from their website right now. 

I'm also looking for such, and think that overall capacity takes a back seat to pass-through ability.

I foresee charging/powering Garmin, with pass-through for a buffer, during the day, then using dynamo for lighting at night, and the Garmin's own battery.

[David Martin]

Or roll your own with a basic charger board (a few $$ from ebay) and a LiPo battery of a size that suits.
Suitable boards are http://www.ebay.co.uk/itm/5pcs-TP4056-Battery-protection-LIPO-Charger-Module-Board-Micro-USB-Parts-TE420-/282300116850?hash=item41ba65ef72

Note: there have been instances of fake TP4056 chips which can lead to danger with LiPo batteries. The ideal thing with this is that you need make six solder connections and it is done. And you can swap out the Lipo for different capacities as you wish.

[Polar Bear]

If I could 'roll my own' I already would have done so but thanks for the suggestion.   

[andrew_s]

There's the zendure A2 : https://www.amazon.co.uk/Zendure-2nd-Portable-Charger-6700mAh/dp/B00YL6DXJY

The limefuel UK site (limefuelstore) seem to be running down their stock but they still have the small 2500 mAh version
http://limefuelstore.com/products/usb-external-battery-pack-aluminum-2500mah-5v-1-0a-blast-l25x.html

[David Martin]

I've got a spare board or several. if I can find a lipo connector I can wrangle a USB chargeable USB power source for you to plug a LiPo battery of your choice into. It has a micro USB power in and I can add a female USB A socket on a trailing lead and a battery connection.

[thing1]

At the compact end of the scale, Ravpower 6700 2.0 looks best mAH per $ and per gram. http://a.co/5pbANzM


Disclaimer: I've never tested that pack, but I have their larger 20100mAh USB C and it works great so far.
I've been tracking best bang-for-buck pass through battery packs for a while, see http://go.splinge.me.uk/batterypacks

[321up]

RAVPower 6700mAh vs Zendure A2 6700mAh

We bought both to use on holiday when our only power was derived from our hub dynamos and infrequent access to mains electricity.  Did some basic tests with mains chargers and both seem to provide pass through charging.  A brief note about the significant differences between them...

RAVPower 6700mAh:  Will provide power for low current devices (e.g. etrex30) and stays on until device is disconnected.  This device would provide power to a high power load (fast charging smart phone) whilst connected to a low power source (500mA mains charger) - given sufficient time both would be fully charged.

Zendure A2 6700mAh:  Switches off output automatically when attached device draws low current (e.g. because attached device has finished charging).  This behaviour may preserve more charge on the powerbank, but the attached device (e.g. mobile phone) may have used some of its charge by morning if it's left charging overnight.  The etrex30 did not draw enough current to keep it on.  Pass through charging only works well if the source (mains charger) has sufficient power output (otherwise power is supplied to the connected device intermittently).

Both took charge from the hub dynamo (via Luxos U).  Both functioned as required for our holiday.  We didn't try pass through charging from the dynamo.  We used two mu duo chargers on the rare occasions we had mains electricity.

[Ham]

https://chargedpower.com/products/chjgdr-10k-lambo-credit-card-power-bank-1 needs to be considered in this category.

Not certain if any of the others now have the combination of light, charge through and fast charge, when I bought mine a few months back it was (one of ?) the only one(s), plus it comes in funky colours

[Polar Bear]

I've got a spare board or several. if I can find a lipo connector I can wrangle a USB chargeable USB power source for you to plug a LiPo battery of your choice into. It has a micro USB power in and I can add a female USB A socket on a trailing lead and a battery connection.

David,

Sorry, I didn't see this originally.   Very grateful for the offer.   I have been busy being distracted by the machinations of life.   

My non technical mid cannot quite work out how everything connects.   I was assuming that I could connect a LiPo battery to a B&M USB werk or similar and, should that battery have pass through charging, mllePB's Garmin 500 touring for instance keeping it topped up for the entire day.  The battery could then be used overnight to charge a phone. 

Does your creation cover such requirements or does it do things differently?

[David Martin]

I've got a spare board or several. if I can find a lipo connector I can wrangle a USB chargeable USB power source for you to plug a LiPo battery of your choice into. It has a micro USB power in and I can add a female USB A socket on a trailing lead and a battery connection.

David,

Sorry, I didn't see this originally.   Very grateful for the offer.   I have been busy being distracted by the machinations of life.   

My non technical mid cannot quite work out how everything connects.   I was assuming that I could connect a LiPo battery to a B&M USB werk or similar and, should that battery have pass through charging, mllePB's Garmin 500 touring for instance keeping it topped up for the entire day.  The battery could then be used overnight to charge a phone. 

Does your creation cover such requirements or does it do things differently?

It is a standard unit. It will take power from wherever, either the power in or the LiPo. PM me and I can put a board in the post - haven't looked at them for a while as I've had other things to do.