Battery packs - what capacity?

[PT1029]

I am looking into getting a charging device to run off my Son dynamo hub.The plan for now is to use my phone with OS maps on to navigate. The plan would be to run the phone off the battery pack, and charge the battery pack from the dynamo, as some devices don't like the charging being interrupted each time the dynamo stops/runs slow (eg up hill).
The longer term aim is for keeping it charged while camping for some days (generally campsites, not wild camping).
So, what size battery pack would be enough to run a phone with gps running all day with the screen on? There is a lot out there, some pointers would be useful to reduce the amount of trawling
I guess this question falls into 2 parts,
Battery for use without a charger,
Battery for use while being charged off the dynamo hub.

The phone is a 2017 Motorola Moto G5 if that helps. 40 miles with a screen set to turning off after 1 or 2 minutes left 2% on the phone battery. Perhaps generous as I didn't need a map for he last 15 - 20 miles!
I might get a Mio or some such at a later date. I don't carry a lap top or kindle.

[Jdsk]

We have rather more devices, and 16,000 mA h is plenty. Details:
viewtopic.php?p=1675240#p1675240

Jonathan

PS: For those without a USB charger powered from the dynamo... it might not be necessary to buy one if you have a battery pack.

[PH]

There are so many variables any answers are either going to be general or other people specifics which might or might not be relevant. This is what I use:
2 x Anker 5,000 mAh powerpacks, a Garmin Explore 2, a HUAWEI P30 phone, a fast 4 port USB wall charger and an igaro D1 dynamo charger running from a SON or Shimano hub.
I've only used the igaro to test it, I'm carrying it as a back up but in these days of fast USB C fast charging, assuming devices support it, I only need access to a wall socket for an average of an hour a day, to keep everything fully topped up. That is, charging four items at once having used the powerpacks in rotation.
I have tested the igaro, charging powerpacks and recharging devices from them, the Anker's are not pass through so can't do both at once.
I do have quite a cushion, if I leave home with everything 100% charged, I'd have enough capacity to last five or six days without doing anything. I could run the igaro all the time and only need a small buffer battery, I might try that on my next tour, use a single powerpack, I'm pretty sure that would be fine, I'd estimate 4 to 6 hours riding a day at my touring speeds would cover my usage.

There's loads of info here, if you haven't already seen it
https://www.cyclingabout.com/lab-test-c ... th-dynamo/

[freiston]

According to GSMArena, the phone battery is 2800mAh so I suppose you could do a trial run on a day ride and see how much you drain the battery in a day including GPS/OS navigation to work out your power requirement. All things being ideal and as reported, a 16,000mAh battery pack would get you 5 complete charges with a bit in reserve (but I wouldn't rely on "field use" giving that).

If you're cycling/camping out where there's little or no data signal, then the phone could use up a lot more battery than usual as apps repeatedly try to connect to servers for whatever reason (such as checking for messages, updates or backing up/uploading/downloading data) so bear that in mind. Some navigation software (Osmand) can navigate with just GPS whilst in airplane mode - so that can save battery but also leaves you "not available". Colder temperatures can have an adverse effect on battery life too (obviously for both the phone and the power bank).

On my last trip out, my phone (Samsung 2018 A8) was reporting 100% battery at about 01:00 a.m. By 08:00 a.m. (without leaving the tent), it was down to 32% iirc.

[PT1029]

Thanks for the tips. Good to know that not all battery packs can be charged while powering something else.
I will investigate more.
Thanks.

[PT1029]

I went for a 10,000mAhr battery, what use I have had suggests a day ride should be quite managable with the phone navigation.- particulartly in airplane mode. it allows through charging which is useful. Also my low battery phone at lunch got well charged over lunch by the battery pack.
I was surprised the OS app on my phone has the red arrow following along the route as I go, even when in airplane mode. Annoyingly though, the screen does nor scroll as you fall off the edge, so manually have to keep moving the screen across.
For multi day trips I'm looking at chargers.
Thanks for your tips.

[NickJP]

I have two Anker power banks - both now several years old - a 3300mAh lipstick unit that I take on long day rides if I need to recharge GPS or phone, and a larger 10000mAh unit if I'm off in the bush for a couple of days camping away from mains power. Those two have met my needs so far.

[PT1029]

Well I used the 10,000mAhr battery yesterday for 50 niles or so (most of the day) with the phone on airplane mode (OS map app tracks it's way along the route even in air plane mode).
I had the screen on most of the day as a test (most of the route was in my head). I started with 4/4 bars on the battery pack and 100% on the phone battery. Ended the day on 2/4 bars on the battery pack and 98% on the phone battery, I had stopped to take a couple of photos shortly before I got home.
So electricity wise, ok.
However I feel a navigation device coming on.... In the dry I use one of those silicon stretchy things to hold the phone on the handle bars, and if likely to be wet a water proof/sealed end case (Oxford Products). I can plug the charging wire in when using the silicon stretchy thing, but not with the waterproof one (but I have seen water proof cases with a charging port).
Both hold the phone well enough, but if I want to take a photo, is a real faff to remove/refit the phone, which is why I feel a navigation device coming on..

[PH]

I had the screen on most of the day as a test (most of the route was in my head). I started with 4/4 bars on the battery pack and 100% on the phone battery. Ended the day on 2/4 bars on the battery pack and 98% on the phone battery, I had stopped to take a couple of photos shortly before I got home.

That seems quite a lot of consumption, though it'll depend on both phone and apps. When delivering, I have google maps, a GPS tracker for my own record plus the Deliveroo and Just Eat apps tracking and messaging, 6 - 8 hours starting and ending with the phone fully charges will take about two thirds of a 5,000 mAh power pack. I haven't used it for touring, I'm away next weekend I might give it a go and keep the Garmin as back-up.

Both hold the phone well enough, but if I want to take a photo, is a real faff to remove/refit the phone, which is why I feel a navigation device coming on..

Plenty of reasons you might want to separate phone and navigation, but that issue seems to be about the case/holder rather than phone/GPS. A Quad Lock, or something similar, allows you to twist the phone off instantly and doesn't obscure the camera lens.