So it turns out most USB power banks won’t charge Exposure brand lights. They describe the mechanism that causes this on their FAQ page and have confirmed with me by email that this is the issue I’ve been having (multiple power banks and 2 different Exposure lights):
“Power banks have a boost converter to generate the 5V output. To save energy they will switch this off if there is no load. Some of them you have to press a button to start, others will test every second or so. We momentarily stop the charging every second to measure the battery voltage for the fuel gauge, some power banks can turn off during this.”
They said another customer reported successfully charging their lights from an Anker 737 Power Core.
Can anyone name any other makes/models they’ve had success with? I’d especially love to know if there are any smaller options in terms of size/weight - this thing is basically double the size/weight of my current ‘main’ power bank while only increasing battery capacity from 20,100 mAh to 24,000 mAh.
FURTHER NOTES:
In the bikepacking race I’m prepping for I’ve heard multiple stories of people not being able to go fast enough for a dynamo to function. I also just don’t really want to go through the process of setting up a dynamo system right now. Would need to charge a power bank from it anyway since going direct to a lot of devices is problematic.
I asked if I could charge a Support Cell (Exposure’s own backup batteries) from a powerbank and then use that to charge the lights. They said there’s a different technical problem that often gets in the way of charging support cells this way.
I know there are even further challenges with powering Exposure lights while they are on. That’s not something I need to do in this situation - I can charge them when they are off.
It would be OK if my ‘main’ powerbank couldn’t charge the Exposure light as long as I could use that power bank to charge a smaller one that does work with the lights.
Once I started looking into this I opened up a whole other can of worms to do with charging rates. My 20,100 mAh Anker battery is a few years old and takes like 8 hours to charge via USB-A. I see now products like the model Exposure linked to above can charge in a fraction of the time, and choosing an appropriate modern Gallium-Nitride based wall-charger can have a big impact on this as well. Looks like with a carefully chosen setup I could potentially charge phone, bike computer, light, and backup batteries from a single wall outlet in 3 hours or less. This might make it worthwhile doing a big spend on all new top-of-the-line battery and charge parts and will still cost less than going to dynamo. Would be curious to hear anyone’s bikepacking-specific GaN charger experiences too. [EDIT: started a separate thread for this: GaN Chargers and High-Speed Power Banks - Device Charging For Bikepacking]
Not really the answer you might be looking for, but if you’re planning to take a computer, you can get the Apple 140w charger. USB-C output. That’s how I charge my anker 737 from 0-100 in 40 minutes or so. Need a 140w capable USB-C to USB-C cable of course.
I have a powerbank by RavPower (RP - PB22) that worked fine charging my exposure strada. I think I purchased it 8 years ago so unlikely to find it now and its quite heavy for the capacity (13,000 mAh) but it worked as I had it charging both my garmin and my light. Suprised to hear you say most powerbanks don’t work. I will be following this thread as I would like to get something with a bit higher capacity.
The Anker 737 is the best charger of all time and I have had so many. Charges everything fast, recharges superfast. Has a display. It is for the moment the king.
I have two Exposure lights and two Nightcore power banks for bike packing.
Lights:
Exposure Strada MK11 SB AKTIV with 10,200 mAh Li-Ion
Exposure Joystick MK16 with 3,500 mAh Li-Ion
Power banks:
Nightcore NB20000
Nightcore NB10000
Both of these power banks can charge the Joystick
Neither power bank can charge the Strada
Aside from the Nightcore banks not charging the Strada light, they are excellent. Very light and compact. I’m also charging iPhone, Hammerhead computer, 4 small Bontrager Ion blink lights, ear buds.
I bought a Mophie Power Station XXL 20000mAh and it does charge the Exposure Strada. It is heavy and larger, so it’s not ideal to add to my kit.
I’m still searching for a good light and compact 20000mAh power bank that can charge the Exposure Strada.
My main criteria for going with one 10000mAh charger and one 20000mAh is that is around the max mAh limit to take on a flight when I’m traveling with my bike (power banks in carry on). I also like to have two separate power banks for redundancy.
Really helpful stuff here so far, thanks all! Hopefully more to come too.
That’s incredible! More info in my other thread about chargers, but this is basically where GaN seems to be taking us. 140w GaN can be about 2/3 the size of the Apple one and also include multiple USB ports for simultaneous charging. I’m thinking 140 might still be more bulk than it’s worth but have been looking at some 65w options as a potential balance between speed and bulk.
Totally shifts the balance between dynamo vs cafe charging if you’re not going somewhere completely remote for days on end. Saw someone saying that in 1hr on a wall plug he’s getting more mAh than he would in a full day of trickle charging from a dynamo.
I wonder if maybe the incompatibility issue is actually part of a fairly recent bit of powerbank tech designed to make these things more efficient by switching off when not needed?
This rec got me really excited til I saw the next post saying it charges Joystick but not Strada. And yes, this is exactly the issue for me. I think given the size/weight penalty of the Anker what I’m ideally looking for is a really simple and size/weight efficient 20k plus a 10k version of the high-tech Anker. Could always use the 20k to recharge the 10k if I needed the high tech version more than once, but then I’m not having to carry that massive 630g brick everywhere. So far doesn’t look like such a product exists though.
That’s good to know - decent weight saving over the Anker too. It’s only 18w output though. That doesn’t really matter for bikepacking but I expect it probably also means the input isn’t very fast. Still the lightest and most compact product in this thread so far that will charge the Strada!
@alexfthenakis Update! I haven’t touched the Mophie XXL in a while, so I pulled it out with the Strada to reconfirm. I’m getting irregular results now. It is charging the Strada 1-2% then the charger is shutting off.
That’s a shame, sounds like the same issue as all the others. Thanks for confirming though!
I just took delivery of a few options not mentioned here so far. I think I can successfully get them open to test without cutting any sealing tape that would prevent me returning them. Will report back once I’ve tried.
Thanks for linking that brand. FYI to others all their products are designed for action sports. Most are water resistant, some are impact resistant, and they even have a line that is designed to function in extreme cold.
The NB20,000 has 30w input, but all the other models I looked at have max 18w input, so will be significantly slower to charge than anything else I’m linking to.
Still good options depending what you’re looking for.
Some updates here. Most significant finding is at least one brand that charges the Strada if you use a USB-C to A adapter and charge via the C port instead of the A. I’ve tested this on two different sized batteries from the same brand with success, and on one other where it doesn’t work. So it’s still going to be hit or miss, but I think this may be a workable option to make a much bigger selection of power banks useable!
I’m currently sitting on a few to try and return:
Anker 737 - 627g on my scales - as linked in original post. This thing really is the bees knees. I just wish it wasn’t so so bulky and heavy! But it works with everything and tells you exactly what’s going on and is really fast. Was going to hold off buying as it’s kind of my in-reserve backup option but a sale brought it down to like £99 - made it a good enough buy that I might consider keeping it regardless of whether I ever take it on a bike.
Baseus 65w 20,000mAh - 464g - cheap for what it is, has a metal casing, and at least as fast as any charger I’m willing to carry right now. Charges Exposure lights using a USB-A to C adapter but not through the USB-A ports themselves (more on this below though). Further testing required before I’m willing to rely on it in a race.
Baseus 30w 10,000mAh - 215g - got it with a voucher code for £17 I think so might keep it even if I decide not to add it to my bikepacking rig. Heavy for a 10k but metal casing and 30w speed is good. Will do Exposure lights through the USB-C port just like its big brother above.
Ugreen 145w 25,000mAh - 506g - was really hopeful about this one given the overall Ugreen product line. No joy with Exposure lights through A or C ports so it’s not for me, but it seems to offer the same speed and battery capacity as the Anker 737 but with a more useable form factor and about 100g less weight.
Zendure 10,000 - 181g - only one that arrived shrinkwrapped, so I might struggle to make a return. I think I’ll still end up opening it though. It’s significantly lighter than the Baseus 10k and should be smaller too. If it can handle Exposure lights it will be my small capacity preferred option.
More on A to C adapters etc: both Baseus models actually do charge through USB-A #2 (but not #1), and only if I plug in using a little USB power monitor thing I bought for all this testing. It continues to charge through A-2 if I remove the tester from the chain and plug the Exposure cable back in fairly quickly, so there’s obviously something about the tester that is smoothing out the power draw and putting the powerbank in the right mode, which it will stay in as long as I don’t remove the USB for long enough to allow it to reset. The power tester is a really cheap and flimsy bit of kit so there’s no chance I’d rely on it during travel to make this work. The USB-A to C adapter seems reliable though so I might be willing to go down this route.
(The idea for the adapter came to me when I brought my Strada and charge cable with me to the Apple store - was there getting the failing battery in my iPhone replaced in prep for the same race. I got the rep to pull every single power bank they sell and we were going to do a test there on the bench. Only issue is Apple only sell special edition versions of Mophie power banks that have USB-C only and no USB-A ports on them, so we never ended up testing. Not sure if I have the patience to go back and try again now that I’ve bought the adapter. Their power banks are all relatively expensive anyway so probably wouldn’t be my main choice.)
EDIT: Sub-100w Recharge Rates:
(Tested using the cheapie tester, a 65w Ugreen GaN charger, and a 100w Ugreen cable)
Zendure 10k - 20w (this is over the spec listed online)
Baseus 10k - 18w (a shame given the 30w output)
Baseus 20k - 57w (spec is 65w - not sure if the powerbank or the charger is the limiter here)
It also charges via the USB-C with an adapter but draws the exact same wattage so no advantage there.
It will do pass-through charging while the powerbank is plugged into the wall, but it can only do one voltage at a time so is limited to 15w in this configuration. That means it’s all going into the light and the powerbank isn’t charging - but presumably once the light is fully charged then the 15w will begin to charge the powerbank instead - handy if you need to plug both in and go to sleep or something. However, if you’re just trying to maximise the amount of mAh you take on during a short stop, the powerbank will charge at 20w if you plug it in all by itself without the light. Best to fill it up solo first and then connect the light afterwards in that case.
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I presume this means the Zendure Supertank and Supertank Pro 26,800mAh models will also work with Exposure, but at the moment neither is priced competitively in UK (both are about double the cost of the Anker 737 for me and about 3x the cost of the 65w Baseus 20k that I’ve got working with the C to A adapter). Both Supertank models are smaller and lighter than the Anker 737 with slightly more battery capacity, so that shows promise - especially since it seems like there are decent discounts for USA buyers at the moment.
If the OG Supertank goes on a hefty discount soon then I’ll probably order one to test out, but otherwise I think my upcoming race setup is going to be the 65w Baseus 20k plus the 20w Zendure 10k. Baseus will be my primary because it recharges fastest, then I’ll have Zendure as backup with the knowledge that it can get me through one night of full-power use from all devices or probably 2 nights of more conservative use.
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Will edit this post to include compatibility with Sirius once I’ve tested it.
This was a fascinating thread and had me researching all sorts of powerbanks I don’t even need.
I only do short 1-2 day rides and my Anker 10,000 mah seems to charge my smaller exposure Sirius light ok. I want to do a full round-down test on it to make sure it can keep it running or if I can plug it in when the battery is at a low level and have it charge while running it. What do you use to check the watts being transferred?
This is such a rabbit hole! Shame manufacturers aren’t always more clear.
I linked mine here, but there are dozens of options on Amazon, eBay, alixpress, etc. they’re cheap and simple and don’t look like it’s worth shopping around too much for the level of accuracy we’re talking about here:
Due to the link between this thread and the one discussing high speed chargers I was wondering if you have tried charging an exposure light with the USB cable connected to one of the high output GaN chargers? Exposure have said they don’t think the light would charge.
Also this powerbank looks good, though not available in the UK by the looks of it.
I am a big fan of my Exposure lights for my 24-Hour racing and have some decent battery knowledge from other hobbies (and I’m an engineer by day so I’m comfortable pushing product limits). I’ve used a Diablo as well as the Zenith with Exposure’s own support cells.
Knowing what I do about batteries, I measured the voltage of the support cells and determined that they are likely using a simple Li Ion battery within their casing and using their electrical connector. I rounded up some old Samsung 25R 18650 cells, wired them in parallel, and 3D printed a housing to keep them in. I used an RC airplane connector and made an adapter for the Exposure connector. Wouldn’t you know, it works a treat! I went a step further and have now used a 1S LiPo battery, commonly used in RC cars, and that works just as well to charge the light while riding.
My understanding is that there is no smarts within the Support Cell so by charging the light with a similar “dumb” battery of the proper voltage, you should be good to go!
99% sure I’ve tested this with my ugreen 65w folding plug charger and had success. Am certain I would have checked because I have an older mains powered 10-port Anker usb charger that I use for all my cycling gadgets and it won’t work with exposure. (Now discontinued but is here: https://www.amazon.com/Anker-10-Port-Charger-PowerPort-iPhone/dp/B00YRYS4T4)
I’ll double check with my GaN one again soon, but unless I come back and say otherwise then it definitely works.
Yeah, this is why it feels frustrating to me that their support cells cost so much and that it seems so hard to get a commercially available battery to charge them.
My Anker power pack makes the light flash green but having left it all night the battery as reported by the light when switched on hasn’t changed so I don’t think it actually charges it.