Fwiw Molicel INR 21700’s are rated for discharge down to -40C (pdf) though charging only down to 0C. I don’t see a need for a sodium ion flashlight just yet, but I’m posting anyway since I guess it’s news despite being stupid.
Fwiw Molicel INR 21700’s are rated for discharge down to -40C (pdf) though charging only down to 0C. I don’t see a need for a sodium ion flashlight just yet, but I’m posting anyway since I guess it’s news despite being stupid.
I know of one chip that is a sodium ion charger but I think it is only available in China and not in the west since the tech is picking up more speed there.
I guess you technically can use a Lithium ion charging chip with a programmable charge voltage like the BQ25300 but the problem is that almost every chip with a programmable charging voltage also has an under voltage shutoff to prevent deep Li-Ion discharge (usually 3, 2.5, or 2V), but that also means that you can only use like 50-80% of the already limited capacity.
One of my next projects is using GreenPak programmable signal matrix (like a very mini FPGA) to make a sodium charging chip I can put in projects.