Portable Battery Packs / Solar Charging

I carry a fair amount of electronics when I hike, many of them USB chargeable. Been looking at the variety of portable charging options for such devices like USB bricks, solar panels, etc. Anyone using this type of stuff for their car camping or hiking gadgets? Not really versed in all this stuff so I'm curious how you'd "size" these things for charges, i.e. if my headlamp is an 1800mAH battery and my GoPro batteries are 2400mAH or whatever am I literally just adding up these capacities and then dividing by the chargers capacity for a number of charges or are there other factors? And are there bricks of this nature that can be charged via a solar panel in addition to plug in USB adapters? My projected use would likely be carrying a USB brick for emergency charges of a headlamp or Delorme InReach and for multi day use in a car camping scenario like charging via a solar panel during the day to recharge the actual brick for charging devices at the end of the day.

Any feedback on the topic would be appreciated. Seems like a lot of different options out there and reviews don't show any real trends one way or the other.

I have one of these Ankers that I have used while winter camping in Baxter State Park. I charged a few phones twice with it. It's popular, pretty cheap, and trivial to use.

Tim

bikehikeskifish said:

I have one of these Ankers that I have used while winter camping in Baxter State Park. I charged a few phones twice with it. It's popular, pretty cheap, and trivial to use.

Tim

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Does the cold drain the charge from these just like conventional batteries? Wondering if I should "upsize" capacity to allow for some drain. How many days were you out with yours before it died?

We have 2 different sized units. The larger, heavier one will charge 2 cell phones, which use more 'juice' than cameras. I forget the 'mah' value, but they pretty much do what they say they will. Not familiar with cold weather use.

DayTrip said:

Does the cold drain the charge from these just like conventional batteries? Wondering if I should "upsize" capacity to allow for some drain. How many days were you out with yours before it died?

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Can't answer that... sorry. I only used it that one time, but plan to use it again this winter. It will charge my phone 3-4X, or 3-4 phones 1X. Mostly I used the phone in airplane mode for photos since there isn't a signal in most of the park and it just burns up the battery searching. There is a decent LTE signal between Roaring Brook and Chimney Pond, actually, in the birch glades below the Basin Ponds.

I know it got a friend through the AT charging a few times per week and recharging the charger while in town.

Tim

DayTrip said:

Does the cold drain the charge from these just like conventional batteries? Wondering if I should "upsize" capacity to allow for some drain. How many days were you out with yours before it died?

Click to expand...

Cold does not drain the charge from batteries. (A common myth...)

A battery is an electro-chemical device. Cold slows the chemical reaction that produces the current and thus can reduce the available current. When rewarmed, the battery can produce as much current (and show the same capacity) as it did before cooling. (In other words, cold does not reduce the amount of energy in a battery, just the rate at which it can be withdrawn. However, the lowered rate may be insufficient for some devices leading some users to conclude the battery was discharged by the cold.)

If a device refuses to operate because the batteries are cold, warm them up and try again.

BTW 1: some charge meters simply measure the open-circuit voltage which can be affected by the temperature.

BTW 2: rechargeable batteries have charging temp limits which can be smaller that the useage or strorage temp limits. NiMH and Li-ion have a charging range of 32F--113F but a usage range of -4F--149F(NiMH)/140F(Li-ion). See http://batteryuniversity.com/learn/article/charging_at_high_and_low_temperatures

Doug

OK. Think I'm gonna get one of these. Looks like exactly what I want and they're all on sale right now. Thanks.

I use an Anker E7 powerbank and get 5-7 charges for an Iphone/Ipad. I keep a charged one in my camper and use it to top off at night, as well as running a small USB fan. I've gotten 8 days camping with it before it was depleted. I also have a Zero Lemon which gives about 2-3 Iphone recharges, and has a solar panel integral to it, but it takes about 2-3 days to recharge it that way, so I usually reserve it as backup power. I have found that the solar panels that Anker sells take too long to recharge to be practical (IIRC they state 39 hours recharge time).

https://www.amazon.com/Anker-26800m...=UTF8&qid=1480367761&sr=1-1&keywords=anker+e7