Exactly. I've been watching for a choice that makes good sense for back-country power needs and solar just isn't there yet for my usage.
Warning, shoddy math ahead. TLDR; This new cell could save 9-10oz off of the current weight of a popular backpacking solar product bringing it in line with the power provided by a 10K mAh power pack over a 5 backpacking day trip. Yay, solar might finally be efficient enough to consider!
I pack a 10K mAh Anker lithium power pack that weighs about 8 ozs. A GoalZero Guide 10 needs to be charged around 4 times to full (plus the one full charge you started with) to match up with the power pack. That takes something like 24 hours of direct sunlight with the included Nomad 7 (7 watt) panel which is probably 4 or 5 days in an average sort of situation. The whole bundle weighs about 19 oz. If I instead bring two 10K mAh batteries at 16 oz, I'm closer to the same weight comparison. That means I need to be on a trip of 8-10 days or more to break even. Anything shorter and I'm better off just carrying charged lithium power packs. Any long periods of cloudy/bad weather, and I'm better off with the power packs. Solar is a tough sell right now.
If I instead was carrying a solar panel at 6g per watt, that would end up around 48g of panel for 7 watts plus whatever weight in fabric you want to hold the solar cells. Let's say we add a nice thick 500 denier cordura fabric backing at 8 oz per sq yard. Since I need about 1 sq ft of backing for the same size of panel as the Nomad 7, that ends up being about 25g of added fabric (heavy duty fabric...). So the new panel would weigh around 75-100g (3-4oz). The Nomad 7 panel weighs 363g (13oz) saving me 8oz or more off the overall weight of 19 oz. Now I'm comparing my 8 oz lithium power pack to an 11 oz solar solution that provides about the same energy over 4-5 days. Suddenly, solar is looking like a possibility for a reasonable length hike especially during months where you can expect better weather.
Now, given that the weight of the panel is no longer a significant portion of the overall weight of the solution, it would make sense to increase the size a little to make it more weight effective. Double the size of the panel and the output to 14W which would add 3-4 more ozs bring it to ~15oz to provide the same power over 5 days that two 10K mAh lithium batteries supply at 16oz. If this "back of the napkin" math is even close, this change by itself will make solar relevant for shorter trips with lowish power needs (10-20K mAh is 4-8 full charges of my cell phone, for example).