Back up power for devices

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wardsgirl

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I use AA batteries for all my appliances on the trail: GPS, headlamps, flashlight, transistor radio, and such. That way, if I run out of battery power, the interchangeability allows me to take a battery from the headlamp to use in the GPS, or take from the radio to power a headlamp, etc. Besides carrying several extra AA batteries to provide back-up power, is there some kind of charger that other hikers/backpackers use to keep from running out of juice?

Does anyone use an 'anker' power source/charger? Does it charge batteries or the battery-operated devices that I outlined above? Or is it used as a power source for modern tech like a cellphone, Kindle, tablet, etc?
 
Anker products were recommended by friends who've done the AT and PCT and so far it has worked well for me. I have an Astro E1 (2nd generation). $21.99 on Amazon.

NOTE - mine came with the micro USB cord to charge the Anker. I have, on more than one occasion, forgotten to bring the iPhone cord, but remembered the charger. Don't make this mistake :)

Tim
 
The device linked by BHSF *is* a spare battery, conveniently combined with a USB socket (and associated circuitry) so you can use it to charge a mobile phone (or similar devices that can charge via USB, perhaps including a GPS receiver). It won't help with things like your headlamp (short of modifying it and/or your lamp with a soldering iron). A handful of AAs would be cheaper and more flexible. Keep them dry, and in winter keep them in an inner pocket so they stay warm.
 
The only electronic device I need to carry in the woods is a compass. It carries its own everlasting electromagnetic backup.
 
^^^ +1 ^^^

I was going to say something like that - excellent.
 
I have a $22 Anker charger for my phone. This summer I had a number of mulit-day hikes / backpacks on my docket. The charger (no bigger than a candy bar)... can charge my phone 3+ times. It was fast and easy.
 
I do the same thing with my stuff. All AA batteries. I use one of those Energizer fast charge plug in chargers and got extra rechargeable batteries. It charges 4 AA batteries in about 15 minutes on the wall outlet and also comes with a car charger. I usually carry an extra set of batteries for each device (GPS and headlamp) so I have more than enough battery life for a full day or night hike.

I also have one of those Anker type chargers (not that brand) which I take for car camping and traveling. Last year I got a Reactik headlamp so I like having the Anker charger for that headlamp, my camera, my phone, my InReach and other USB stuff. I got a relatively large one and get at least 3 full charges for my smartphone as well as tanking up other devices. So I generally have stayed with the rechargeable batteries and spares for the convenience on the trail but I rarely backpack overnight or for multiple days. The USB charger is super convenient in camp. It's weight is heavier than say half a dozen extra batteries so I don't know what it is saving from that perspective.

I'm not aware of any portable charger capable of charging regular batteries. Not sure that's possible but I'm sure DougPaul could expand on that thought. :)

P.S. I've found that my compass makes a horrible flashlight. :p
 
If by regular batteries you mean regular rechargeable nicads or the like then it is possible. My spot uses AAA batteries, lithiums or nicads. You can recharge any rechargeable AAA battery in the device for use with other devices.

Going the Anker/USB route might not save weight but it pays for itself in not buying batteries very quickly.
 
The only electronic device I need to carry in the woods is a compass. It carries its own everlasting electromagnetic backup.

tsk-tsk. No lighting mechanism? :)
 
I do have several carbide lamps, previously used during my cave mapping career in NY an NM. Honestly, a simple headlamp with a single spare set of batteries does the trick for local hiking, should I get caught out after dark, and maybe a dollar store led backup, no need for anything more exotic or expensive.
 
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I agree entirely, I carry a headlamp with lithium triple As and its good for many years. I also carry a lithium coin cell backup LED headlamp.
 
Thanks for all the info!

FWIW, I always carry a compass and I know how to use it.

None of my devices, including the GPS, are ever attached to a computer. I don't carry a cell phone and I rarely carry a camera.

It sounds like my devices can be best powered by an extra set of AA batteries.

The "anker" charger is something that powers devices that have a slot for a wire of some sort or a USB connection.

Unless I get some new-fangled devices that can be tethered to a power source, other than a AA battery, I'll stick with the AAs.
 
A handful of AAs would be cheaper and more flexible. Keep them dry, and in winter keep them in an inner pocket so they stay warm.
It is not necessary to keep the AAs (or pretty much any battery) warm in storage and transport--only when in use. And lithium AAs (non-rechargeable) work well down to ~-40F.

In general, at low temps, lithium (non-rechargeable) is best, NiMH, NiCad, LIon (lithium recahargeable) next, alkaline third, and zinc-carbon (dry cells) worst.

The exact temperature limits depend on the state of the battery and the device.

Note that there are also temperature range limits for charging rechargeable batteries--in particular, the lower limit is 32F for charging LIon, NiMH, and NiCad. Thus using one of the external batteries to charge a cellphone out in the cold may damage the internal battery. (It should be OK if one warms both batteries with body heat before charging the internal battery.) See http://batteryuniversity.com/learn/article/charging_at_high_and_low_temperatures for more detail.

FWIW, I prefer field-replaceable AA or AAA batteries in my hiking electronics (GPS and headlamps). I use (non-rechargeable) lithium or pre-charged NiMH cells. My cellphone has an internal LIon battery, but it is normally turned off when hiking so the battery should be OK if I need it. (This is for hikes of a few days or less.)

Doug
 
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It is not necessary to keep the AAs (or pretty much any battery) warm in storage and transport--only when in use. And lithium AAs (non-rechargeable) work well down to ~-40F.

When hiking, and especially backpacking, the batteries I carry will usually be either rechargeable lithium (high charge density, less waste) or old-fashioned alkaline (cheap and available at any store). Both have failed me in temps in the single digits Fahrenheit - especially when it comes to powering my cameras.
Many electronic devices, such as cameras, are sensitive to voltage and are designed not to operate if the battery isn't producing at (nearly) full strength. Headlamps should not have this problem; I don't know about GPS or portable phones.

I find it much easier to carry a spare battery pack in a warm pocket, than to warm up a battery before I can use it. Keeping it warm inside the camera is not possible, so you want it nice and warm when you put it in. Put the old battery in your warm pocket and keep switching as each one cools in turn.
 
Many electronic devices, such as cameras, are sensitive to voltage and are designed not to operate if the battery isn't producing at (nearly) full strength. Headlamps should not have this problem; I don't know about GPS or portable phones.
All electronic devices are sensitive to voltage, some more so than others. The output voltage of a battery is a function of its chemistry, condition, state of charge, temperature, and the load (current drawn). The temperature at the time of use is important, the storage temp (within reasonable limits) is not.

Batteries are electro-chemical devices--as the temp drops, the chemistry slows down, the available current decreases, and the internal resistance increases. An increased internal resistance will cause the voltage to drop more when a current is drawn.

I find it much easier to carry a spare battery pack in a warm pocket, than to warm up a battery before I can use it. Keeping it warm inside the camera is not possible, so you want it nice and warm when you put it in. Put the old battery in your warm pocket and keep switching as each one cools in turn.
For a short trip, keeping one's spare batteries pre-warmed by body heat is practical. However, for a long trip requiring multiple spares it is perfectly OK to keep only one set of spares pre-warmed and the rest at ambient temp in one's pack.

Lithium primary (non-rechargable) have the best low-temp performance of any of the battery chemistries typically used in hiking equipment*. The low temp tolerance is good enough that there is little if anything to be gained by keeping them warm at typical NE temps (say >=0F). This is one of the reasons why they are used in PLBs...

* Dry cell (carbon-zinc) and alkaline are the worst.

Doug
Electrical Engineer
 
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