For the OP's question, define your INCH event.

To me, an INCH event is where things are really messed up and quite possible that supporting infrastructure is already gone or in bad shape. Meaning, would there still be a need to charge a cell phone? Carrying a few extra batteries for a flashlight is doable depending on supposed INCH event.

Depending on cellphone, carrying extra batteries which are lightweight would be my preference. 4-5 batteries ($50.00 and 8 oz total weight) for my phone would give about 16,000 mAh of battery time and could last months with careful usage. Again, depending on the INCH event, having a 12 volt to USB cable will give a lot of charging options from many sources such as car batteries etc. The 12 volt end of the cable can easily have a cigarette type connector added to it also. I have a similar cable but it has 2x USB connectors and has come in handy and mostly recently during a 32 hour power outage here at home which was caused by a windstorm.

Although the foldable type of solar panel products are decent (there is some real garbage though), they are really not suited for on the go unless you plan to stop for to allow the charger to have enough sun time to charge the batteries. Also what happens if it rains and there are clouds for days on end? Solar charge time may stretch into 10's of hours, if not more.

As for SLA type batteries, they can hold plenty of power but are heavy and not really suited for on the go travel. A better solution especially if you have a phone such the Apple iPhone in which they don't have a replaceable battery, might be the Anker 26800mAh charger Anker is a very reliable brand and makes quality products. One or two of these chargers in a backpack will give plenty of charging capability.


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Earth and sky, woods and fields, lakes and rivers, the mountain and the sea, are excellent schoolmasters, and teach some of us more than we can ever learn from books.

John Lubbock