I want to start off by saying that I have had DIY experience powering flashes from external power supplies. One of my 460 flashes was modified five years ago in order to use the 5 V leg from a PC power supply and it has worked flawlessly since when at home. However, impractical for outdoor use if for no other reason than lack of AC available. Up until now, I have used 4 lithium 10 year shelf life AA's, but even the best of these is used up fairly quickly by flash and they are expensive. I've never been impressed by AA rechargeables, so have stuck with the lithiums. I know they say "eneloop" is supposed to be a step up, but by the time those and a charger are acquired, I might as well buy a flash with built in power pack. The idea is a power pack possibility that's cheap, like under $20 and that includes the charger.....
Around the web, searches keep showing SLA based modifications. While I feel these might be ok, the high cost of the chargers puts me off.
Enter the rechargeable lithium ion battery pack similar to
this one. I use several of these for my telescope equipment and they have performed flawlessly even in more extreme temperatures over the last couple of years. No separate charger needed and close to my budget. The problem is that, at least with the Talentcells, the emphasis of the most current output is on the 12V leg and not the lesser voltages. The one pictured isn't the exact battery I use for the scopes, but the 12V, 7000mAh or greater.
My local Walmart has the same time of
battery, but more designed for cell phone charging, and I thought it might be ideal since I currently power the indoor 460 with the 5V PC supply. However, after modifying a USB cable to connect to the flash, all I get when I turn on the flash is a single blinking red light, so my guess isn't that this battery isn't robust enough in the current (mAh) area.
For any DIY who have successfully completed such a task, I'd like to hear how you did it on a budget.
Thank you.