Most of what you want to do is not difficult. if you have a general or better license, it is all within your skill range. You just need the details. However I am wondering about your initial assumptions.

I have done a lot of disaster work, Katrina and more. The first question is who do you want to talk to and why? During most disasters, the HF bands are like a major contest or field day. I would not want my only comms to be 40/30m QRP. Especially CW only. Unless you have a specific comm plan that will work under those conditions.

This is especially true if you intend to back-pack the rig. Space and weight will be very precious. I have thought about this for several years and tried various options. What I want is a good general coverage receiver and a good commercial/ham vhf/uhf HT rig with assorted accessories. Actually I carry two dual bands. I won't go into details about my choice, just playing the devils advocate here. I also have a FT-857d in a box, but that is another story.

But that is me. You obviously have other needs. I am curious as to how you intend to use the radio you mentioned. Neat rig though, and I would love to play with it. However is just does not seem to me to be appropriate for the intended use.

Oh, all my Ht's are USB charged. I have been living off the grid for more than 15 years now so we can talk about that later.

Not trying to be picky... just curious about your intent.

Nomad

Forgot to add a link to hfpack. It is THE source for manpack radio. Mostly green (military) but also a huge and very knowledgeable group of QRP and hi tech battery folks.

http://groups.yahoo.com/group/hfpack/join

Nomad

You could reduce the weight and size of the SLA battery buy building your own Lithium Ion Battery from individual cells such as these Genuine 18650 Panasonics.

Just place 4 cells into a battery holder to get a voltage between 16.8V (fully charged) to around 12V when depleted.

Just use a DC-DC regulator (adjusted with 12v output) and a 18650 Battery Holder /box/switch/fuse/lead out with the appropriate connector to the QPR station. You could even add LED Voltage Metering to measure the battery status before the DC-DC regulation stage or even after with a simple switch!


This would give you around 48Whrs or around 8 hrs (93% effiency with the DC-DC regulation) use before recharging the batteries in a conventional 4 station charger like the Nitecore Intellichager i4 (which itself will take a 12V Auto line in and also has NiMh AA/AAA charging capabilities)

You could do the same with 4 18650 LiFePo4 cells instead without the DC regulator as the maximum/minimum voltage out would vary between 13V and 11.5 Volts. But you would only get a realistic 3-4 hrs use for a slightly heavier battery.

Additional Individual cells could also be carried in spare battery cases and could even be used in other devices such as flashlights etc.